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Sample records for barotrauma

  1. Ear barotrauma

    Science.gov (United States)

    Barotitis media; Barotrauma; Ear popping; Pressure-related ear pain; Eustachian tube dysfunction ... The air pressure in the middle ear is most often the same as the air pressure outside of the body. The Eustachian tube is a connection between the middle ...

  2. Roller coaster-induced barotrauma.

    Science.gov (United States)

    Al-Khudari, Samer; Loochtan, Michael; Yaremchuk, Kathleen

    2011-03-01

    We present the case of a 24-year-old male who presented to the otolaryngology clinic for otalgia and aural fullness after riding a roller coaster. We present his clinical course and outcome and briefly discuss the mechanism of injury and otologic barotrauma. Roller coasters have been reported as the cause of many different types of injuries, but this is the first reported case of otologic barotrauma. As the engineering for roller coasters continues to advance in terms of increasing speed, otolaryngologists need to be aware of a new etiology of otologic barotrauma. PMID:21344425

  3. Barotrauma ocular durante mergulho autônomo

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    Maria Fernanda Abalem de Sá

    2011-12-01

    Full Text Available Relato de um caso de barotrauma ocular bilateral relacionado ao mergulho autônomo, com hemorragia conjuntival e periocular. Alguns conceitos de física e cuidados durante o mergulho são reportados para um melhor entendimento da fisiopatogenia do quadro, de modo que se possa melhor orientar os pacientes quanto à prevenção.

  4. Update on Middle Ear Barotrauma after Hyperbaric Oxygen Therapy—Insights on Pathophysiology

    OpenAIRE

    Lima, Marco Antônio Rios; Farage, Luciano; Cury, Maria Cristina Lancia; Bahamad, Fayez

    2014-01-01

    Introduction Middle ear barotrauma is the most common side effect of hyperbaric oxygen therapy. Knowledge and understanding of its pathophysiology are crucial for an accurate diagnosis and proper decision making about treatment and prevention. Objective Describe up-to-date information on pathophysiology of middle ear barotrauma after hyperbaric oxygen therapy considering the physiology of pressure variation of the middle ear. Data Synthesis Middle ear barotrauma occurs especially during the c...

  5. Delayed Diagnosis of Pharyngeal Perforation following Exploding Tyre Blast Barotrauma

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    Samantha M. Field

    2014-01-01

    Full Text Available Introduction. Pharyngoesophageal perforation secondary to barotrauma is a rare phenomenon that can have serious complications if identified late. It is challenging to detect due to nonspecific symptoms. We present a case in which detection proved difficult leading to delayed diagnosis. Case Report. A 27-year-old mechanic presented with haemoptysis, dysphonia, and odynophagia after a car tyre exploded in his face. Flexible nasoendoscopy (FNE revealed blood in the pharynx, thought to represent mucosal haemorrhage. Initial treatment consisted of IV dexamethasone and antibiotics. After 3 days, odynophagia persisted prompting a CT scan. This revealed a defect in the posterior hypopharynx and surgical emphysema in the deep neck tissues. Contrast swallow confirmed posterior hypopharyngeal leak. NG feeding was commenced until repeated contrast swallow confirmed resolution of the defect. Discussion. Prompt nonsurgical management of pharyngoesophageal perforation has good outcomes but untreated perforation can have serious complications. FNE should be performed routinely, but only a contrast swallow can diagnose a functional perforation. Clinicians should have a high index of clinical suspicion when patients present with barotrauma and odynophagia. Patients should be kept nil by mouth until perforation has been excluded. Conclusion. When faced with cases of facial barotrauma, clinicians should have a low threshold for further imaging to exclude pharyngoesophageal perforation.

  6. Delayed Diagnosis of Pharyngeal Perforation following Exploding Tyre Blast Barotrauma.

    Science.gov (United States)

    Field, Samantha M; Manjaly, Joseph G; Ramdoo, S Krishan; Jones, Huw A S; Tatla, Taran S

    2014-01-01

    Introduction. Pharyngoesophageal perforation secondary to barotrauma is a rare phenomenon that can have serious complications if identified late. It is challenging to detect due to nonspecific symptoms. We present a case in which detection proved difficult leading to delayed diagnosis. Case Report. A 27-year-old mechanic presented with haemoptysis, dysphonia, and odynophagia after a car tyre exploded in his face. Flexible nasoendoscopy (FNE) revealed blood in the pharynx, thought to represent mucosal haemorrhage. Initial treatment consisted of IV dexamethasone and antibiotics. After 3 days, odynophagia persisted prompting a CT scan. This revealed a defect in the posterior hypopharynx and surgical emphysema in the deep neck tissues. Contrast swallow confirmed posterior hypopharyngeal leak. NG feeding was commenced until repeated contrast swallow confirmed resolution of the defect. Discussion. Prompt nonsurgical management of pharyngoesophageal perforation has good outcomes but untreated perforation can have serious complications. FNE should be performed routinely, but only a contrast swallow can diagnose a functional perforation. Clinicians should have a high index of clinical suspicion when patients present with barotrauma and odynophagia. Patients should be kept nil by mouth until perforation has been excluded. Conclusion. When faced with cases of facial barotrauma, clinicians should have a low threshold for further imaging to exclude pharyngoesophageal perforation. PMID:25525540

  7. Barotrauma as aetiological cascade of fatal intrapulmonary plastic bronchitis in a post-Fontan child

    OpenAIRE

    Elahi, Maqsood; Poh, Chin-Leng; Ravindranathan, Hari; Grant, Peter

    2012-01-01

    The role of barotrauma in the exaggeration of plastic bronchitis after Fontan circulation has yet to be examined. We aim to describe a case of a 4-year old post-Fontan circulation girl where barotrauma suffered during commercial air travel played a role in the aetiological cascade of plastic bronchitis.

  8. MRI findings of otic and sinus barotrauma in patients with carbon monoxide poisoning during hyperbaric oxygen therapy.

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    Ping Wang

    Full Text Available BACKGROUND AND PURPOSE: To study the MRI findings of otic and sinus barotrauma in patients with carbon monoxide(CO poisoning during hyperbaric oxygen (HBO therapy and examine the discrepancies of otic and sinus abnormalities on MRI between barotrauma and acute otitis media with effusion. MATERIALS AND METHODS: Eighty patients with CO-poisoning diagnosed with otic and sinus barotrauma after HBO therapy were recruited. Brain MRI was performed to predict delayed encephalopathy. Over the same period, 88 patients with acute otitis media with effusion on MRI served as control. The abnormalities of the middle ear and paranasal sinuses on MRI were noted and were compared between groups. Nine patients with barotrauma were followed up by MRI. RESULTS: In the barotrauma group, 92.5% of patients had bilateral middle ear abnormalities on MRI, and 60% of patients had both middle ear cavity and mastoid cavity abnormalities on MRI in both ears. Both rates were higher than those in the control group (p = 0.000. In the two groups, most abnormalities on MRI were observed in the mastoid cavity. The rate of sinus abnormalities of barotrauma was 66.3%, which was higher than the 50% in the control group (p = 0.033. In the nine patients with barotrauma followed up by MRI, the otic barotrauma and sinus abnormalities had worsened in 2 patients and 5 patients, respectively. CONCLUSION: MRI is able to depict the abnormalities of otic and sinus barotrauma in patients with CO-poisoning during HBO therapy and to differentiate these from acute otitis media with effusion.

  9. Cardioplegia cristalóide, barotrauma e função endotelial: considerações experimentais Crystalloid cardioplegia, barotrauma and endothelium function: experimental considerations

    Directory of Open Access Journals (Sweden)

    Paulo Roberto B Évora

    1996-06-01

    Full Text Available O presente ensaio experimental estudou o efeito da infusão de solução cardioplégica cristalóide a altas pressões sobre a função endotelial de artérias epicárdicas de cães. Não se encontraram alterações a nível de receptores (curvas dose-respostas à ACH e ADP; da transdução do sinal iniciado nos receptores/sitema de G-proteínas (fluoreto de sódio e nos processos intracelulares da produção de EDRF/ NO (fosfolipase C e ionóforo do cálcio A23187. A função da musculatura lisa vascular não foi afetada quando se analisaram as respostas relaxantes (nitroprussiato de sódio e isoproterenol e contrateis (KCI e prostaglandina 2alfa. Estes achados permitem as seguintes considerrações especulativas: a O barotrauma produzido pela infusão da cardioplegia cristalóide a altas pressões ocorreria apenas em circulações coronarianas previamente doentes? b Uma vez que as infusões duraram de 2 a 3 minutos, seria o barotrauma coronariano um fenômeno dependente do tempo de infusão? c Para que ocorra o barotrauma seriam necessários níveis mais elevados de potássio? d Questionar a existência do fenômeno do barotrauma coronariano produzido pela infusão de soluções cadioplégicas pelo menos nas condições experimentais utilizadas, e A metodologia empregada estuda apenas as reatividades vasculares de artérias coronárias epicárdicas. Estas artérias seriam menos sensíveis aos efeitos da pressão de infusão da cardioplegia do que a microcirculação coronariana? f Seria a circulação coronária do cão menos sensível a altas pressões do que do homem? Estas observações experimentais sugerem que a infusão de cardioplegia cristalóide, moderadamente hipocalêmica, a altas pressõe em um tempo de 2 a 3 minutos, não interfere com a produção de EDRF/NO pelo endotélio de coronárias epicárdicas do cão.Experiments were performed in "organ chambers" to investigate if high pressures infusions of crystalloid cardioplegia

  10. Understanding barotrauma in fish passing hydro structures: a global strategy for sustainable development of water resources

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Colotelo, Alison HA; Pflugrath, Brett D.; Boys, Craig A.; Baumgartner, Lee J.; Deng, Zhiqun; Silva, Luiz G.; Brauner, Colin J.; Mallen-Cooper, Martin; Phonekhampeng, Oudom; Thorncraft, Garry; Singhanouvong, Douangkham

    2014-03-24

    Freshwater fishes are one of the most imperiled groups of vertebrates and species declines have been linked to a number of anthropogenic influences. This is alarming as the diversity and stability of populations are at risk. In addition, freshwater fish serve as important protein sources, particularly in developing countries. One of the focal activities thought to influence freshwater fish population declines is water resource development, which is anticipated to increase over the next several decades. For fish encountering hydro structures, such as passing through hydroturbines, there may be a rapid decrease in pressure which can lead to injuries commonly referred to as barotraumas. The authors summarize the research to date that has examined the effects of rapid pressure changes on fish and outline the most important factors to consider (i.e., swim bladder morphology, depth of acclimation, migration pattern and life stage) when examining the susceptibility of barotraumas for fish of interest.

  11. A Preliminary Assessment of Barotrauma Injuries and Acclimation Studies for Three Fish Species

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Walker, Ricardo W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-12-15

    Fish that pass hydro structures either through turbine passage, deep spill, or other deep pathways can experience rapid decreases in pressure that can result in barotrauma. In addition to morphology and physiology of the fish’s swim bladder, the severity of barotrauma is directly related to the volume of undissolved gas in fish prior to rapid decompression and the lowest pressure the fish experience as they pass hydro structures (termed the “nadir”). The volume of undissolved gas in fish is influenced by the depth of acclimation (the pressure at which the fish is neutrally buoyant); therefore, determining the depth where fish are neutrally buoyant is a critical precursor to determining the relationship between pressure changes and injury or mortality.

  12. Barodontalgias, dental and orofacial barotraumas: a survey in Swiss divers and caisson workers.

    Science.gov (United States)

    Zanotta, Cristina; Dagassan-Berndt, Dorothea; Nussberger, Peter; Waltimo, Tuomas; Filippi, Andreas

    2014-01-01

    Changing ambient pressure can lead to medical conditions in body cavities filled with air. Intraoral pain elicited by changes in pressure is referred to as barodontalgia. Dental barotraumas are defined as pressure-induced damages of teeth and restorations. The pathophysiologic background so far is not completely clear. The present study deals with dental and orofacial symptoms which can occur as a result of pressure variations. With the aid of cantonal administrations, diving associations, and tunnel construction firms, 520 pressure-exposed individuals (499 scuba/ professional divers, 21 caisson workers operating at excess pressure) were questioned regarding dental problems. A personal interview was conducted with affected individuals. Problems in the dental area were experienced by 15% of all respondents. Toothaches were suffered by 10.2% of the participants. Tooth injuries occurred in 6.3% of all interviewees (26 fractured amalgam restorations, 4 crown fractures, 3 losses of tooth fragments). A proportion of 11.3% among the respondents complained about temporomandibular joint problems or mucosal irritations (for example aphthae) related to the mouthpieces. Barotraumas outside the dental area were incurred by 31.9% of the divers. Of these, 69.9% concerned the ears and 65.6% occurred during the descent. Based on the results obtained from the survey and taking into account the current literature, recommendations for the prevention of barotraumas in divers and caisson workers were prepared. Diagnostic exclusion of dental pathologies and avoidance of retentive reconstruction materials are important factors for the prevention of barodontalgias and dental barotraumas. PMID:24853026

  13. [The influence of barometric pressure changes in the oral cavity: dental barotrauma and barodontalgia].

    Science.gov (United States)

    Nakdimon, I; Zehavi, E; Chapnik, L; Zadik, Y

    2014-07-01

    Several oro-facial physiologic and pathologic phenomena affect individuals during flight or self-contained underwater breathing apparatus (SCUBA) diving. Physicians and dentists who treat aircrews and divers are occasionally challenged by those manifestations, though their uncommon appearance. This article reviews the two main barometric-related phenomena in the oral cavity: dental barotrauma and barodontalgia. Dental barotrauma includes all barometric-related dental mechanical phenomena. Tooth fracture or failure of dental restoration usually appears in a tooth with a leaking restoration or secondary caries lesion. In addition, changes in barometric pressure can cause a reduction in the retention of dental restoration and appliance. Barodontalgia is the oral pain which evoked during changes of the atmospheric pressure. This manifestation can be classified as a direct or non-direct pain. In most cases, the direct pain is caused by deterioration of pre-existed oral disease, whereas the source of the nondirect pain is an extra-oral facial barotrauma. These two barometric-related manifestations can cause a decrease in life quality and jeopardize the safety of flight or diving. PMID:25219097

  14. A forensic investigation into the etiology of bat mortality at a wind farm: barotrauma or traumatic injury?

    Science.gov (United States)

    Rollins, K E; Meyerholz, D K; Johnson, G D; Capparella, A P; Loew, S S

    2012-03-01

    Migrating bats have increased mortality near moving turbine blades at wind farms. The authors evaluated competing hypotheses of barotrauma and traumatic injury to determine the cause. They first examined the utility of lungs from salvaged bat carcasses for histopathologic diagnosis of barotrauma and studied laboratory mice as a model system. Postmortem time, environmental temperature, and freezing of carcasses all affected the development of vascular congestion, hemorrhage, and edema. These common tissue artifacts mimicked the diagnostic criteria of pulmonary barotrauma; therefore, lung tissues from salvaged bats should not be used for barotrauma diagnosis. The authors next compared wind farm (WF) bats to building collision (BC) bats collected near downtown Chicago buildings. WF bats had an increased incidence in fracture cases and specific bone fractures and had more external lacerations than BC bats. WF bats had additional features of traumatic injury, including diaphragmatic hernia, subcutaneous hemorrhage, and bone marrow emboli. In summary, 73% (190 of 262) of WF bats had lesions consistent with traumatic injury. The authors then examined for ruptured tympana, a sensitive marker of barotrauma in humans. BC bats had only 1 case (2%, 1 of 42), but this was attributed to concurrent cranial fractures, whereas WF bats had a 20% (16 of 81) incidence. When cases with concurrent traumatic injury were excluded, this yielded a small fraction (6%, 5 of 81) of WF bats with lesions possibly consistent with barotrauma etiology. Forensic pathology examination of the data strongly suggests that traumatic injury is the major cause of bat mortality at wind farms and, at best, barotrauma is a minor etiology. PMID:22291071

  15. [Serious pulmonary barotrauma in a child after first-time scuba dive].

    Science.gov (United States)

    Le Guen, H; Halbert, C; Gras Le Guen, C; Coulange, M

    2012-07-01

    Scuba diving is increasingly popular for children. However, this activity, including in shallow water, can be responsible for severe accidents. We report the case of a 13-year-old boy who dove for the first time in the Mediterranean Sea and suffered pulmonary barotraumas, complicated by arterial gas embolism with pneumomediastinum, cerebral, and coronary injuries. Any symptoms occurring after a dive, even in shallow water, must be considered a diving accident. Emergency medical personnel should contact a hyperbaric center for advice. In case of coronary or cerebral gaseous embolism, specific management requiring therapeutic recompression is urgently required. PMID:22682518

  16. Ruptura gástrica por barotrauma Barogenic rupture of the stomach

    OpenAIRE

    Rodrigo Severo de Camargo Pereira; Roberta Thiery Godoy Arashiro; Rogerio Saad-Hossne

    2008-01-01

    INTRODUÇÃO: A ruptura gástrica por barotrauma é uma causa rara de abdome agudo perfurativo, sendo geralmente tratada por laparotomia e rafia primária da lesão. Nas reanimações cardiopulmonares pode ocorrer 9 a 12% de lesões de mucosa gástrica. RELATO DO CASO: Mulher no 5º dia de puerpério necessitou intubação orotraqueal devido à pneumonia hospitalar. Após procedimento evoluiu com distensão abdominal importante, associada a sinais de choque séptico. Após radiografia simples de abdome foi cons...

  17. Assessment of Barotrauma from Rapid Decompression of Depth-Acclimated Juvenile Chinook Salmon Bearing Radiotelemetry Transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Carlson, Thomas J.; Welch, Abigail E.; Stephenson, John R.; Abernethy, Cary S.; Ebberts, Blaine D.; Langeslay, Mike; Ahmann, Martin L.; Feil, Daniel H.; Skalski, J. R.; Townsend, Richard L.

    2009-11-01

    This study investigated the mortality of and injury to juvenile Chinook salmon Oncorhynchus tshawytscha exposed to simulated pressure changes associated with passage through a large Kaplan hydropower turbine. Mortality and injury varied depending on whether a fish was carrying a transmitter, the method of transmitter implantation, the depth of acclimation, and the size of the fish. Juvenile Chinook salmon implanted with radio transmitters were more likely than those without to die or sustain injuries during simulated turbine passage. Gastric transmitter implantation resulted in higher rates of injury and mortality than surgical implantation. Mortality and injury increased with increasing pressure of acclimation. Injuries were more common in subyearling fish than in yearling fish. Gas emboli in the gills and internal hemorrhaging were the major causes of mortality. Rupture of the swim bladder and emphysema in the fins were also common. This research makes clear that the exposure of juvenile Chinook salmon bearing radiotelemetry transmitters to simulated turbine pressures with a nadir of 8-19 kPa can result in barotrauma, leading to immediate or delayed mortality. The study also identified sublethal barotrauma injuries that may increase susceptibility to predation. These findings have significant implications for many studies that use telemetry devices to estimate the survival and behavior of juvenile salmon as they pass through large Kaplan turbines typical of those within the Columbia River hydropower system. Our results indicate that estimates of turbine passage survival for juvenile Chinook salmon obtained with radiotelemetry devices may be negatively biased.

  18. Barotrauma em peixes em usinas hidrelétricas: ferramentas para o estudo

    Energy Technology Data Exchange (ETDEWEB)

    Do Vale Beirao, Bernardo; Castelo Branco Marciano, Natlia; de Souza Dias, Luma; Carvalho Falco, Ricardo; Wander Dias, Edson; Leite Fabrino, Daniela; Barreira Martinez, Carlos; Martins Da Silva, Luiz Gustavo; Walker, Ricardo W.; Brown, Richard S.; Deng, Zhiqun

    2015-09-30

    The main source of electric power generation in Brazil comes from hydropower plants, nevertheless, the installed power is expected to raise 56.8%, reaching a total of 116,000 MW at the year 2020. The increase at the hydroelectric sector will be responsible for a series of fish community impacts. One of the impacts over the fish community is related to fish kills due to downstream passage through turbines or fish entrance at the draft tube from the tailrace. Usually when there is a maneuver and the turbine stops, fish get attracted and enter the draft tube and, just as the downstream passage through a turbine, when the turbine starts, a rapid decompression occurs and can cause barotrauma. When such events happen, according to Boyle’s law (P1V1=P2V2), swim bladder volume expands at the same rate that the pressure decreases, which can lead to the organ’s rupture.

  19. Nasopharyngeal cancer mimicking otitic barotrauma in a resource-challenged center: a case report

    Directory of Open Access Journals (Sweden)

    Daniel Adekunle

    2011-10-01

    Full Text Available Abstract Introduction Nasopharyngeal cancer commonly manifests with cervical lymphadenopathy, recurrent epistaxis and progressive nasal obstruction. Neuro-ophthalmic and otologic manifestations can also occur. Isolated otologic presentations of nasopharyngeal cancer are rare and the diagnosis of nasopharyngeal cancer may not be foremost in the list of differentials. Case presentation We present the case of a 29-year-old Nigerian woman with bilateral conductive hearing loss and tinnitus after air travel. There were no other symptoms. The persistence of the symptoms after adequate treatment for otitic barotrauma necessitated re-evaluation, which led to a diagnosis of nasopharyngeal cancer. Conclusion Isolated otologic manifestations of nasopharyngeal cancer are rare in regions with low incidence of the disease. There is a need for it to be considered as a possible differential in patients presenting with bilateral serous otitis media.

  20. Ruptura gástrica por barotrauma Barogenic rupture of the stomach

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    Rodrigo Severo de Camargo Pereira

    2008-09-01

    Full Text Available INTRODUÇÃO: A ruptura gástrica por barotrauma é uma causa rara de abdome agudo perfurativo, sendo geralmente tratada por laparotomia e rafia primária da lesão. Nas reanimações cardiopulmonares pode ocorrer 9 a 12% de lesões de mucosa gástrica. RELATO DO CASO: Mulher no 5º dia de puerpério necessitou intubação orotraqueal devido à pneumonia hospitalar. Após procedimento evoluiu com distensão abdominal importante, associada a sinais de choque séptico. Após radiografia simples de abdome foi constado pneumoperitôneo. Submetida à laparotomia exploradora evidenciou-se ruptura de pequena curvatura gástrica de 7 cm. O tratamento da lesão foi com sutura primária. Recebeu alta no 14º do pós operatório após término do tratamento para pneumonia. CONCLUSÃO: Apesar de rara, a ruptura gástrica por barotrauma deve ser sempre aventada quando após reanimação cardiopulmonar houver distensão abdominal refratária à sondagem naso-gástrica.BACKGROUND: Barogenic rupture of the stomach is a rare cause of acute perforated abdomen generally treated by laparotomy and primary wound suture. The lesion of gastric mucosa may occur during cardiopulmonary resuscitation in 9 to 12% of cases. CASE REPORT: Woman was intubated in the fifth day of delivery due to nosocomial pneumonia. She underwent to abdominal distension associated to septic shock signs after the procedure. The abdominal X-ray showed pneumoperitoneum. She was submitted to laparotomy and a 7 cm rupture in the gastric small curvature was found. The lesion was treated by primary suture. The patient was discharged 14 days after the surgery, in the ending of pneumonia treatment. CONCLUSION: Besides rare, barogenic gastric rupture must be inquired when after cardiopulmonary resuscitation the patient presents abdominal distension ovenproof to nasogastric tube.

  1. Recovery of barotrauma injuries in Chinook salmon, Oncorhynchus tshawytscha from exposure to pile driving sound.

    Directory of Open Access Journals (Sweden)

    Brandon M Casper

    Full Text Available Juvenile Chinook salmon, Oncorhynchus tshawytscha, were exposed to simulated high intensity pile driving signals to evaluate their ability to recover from barotrauma injuries. Fish were exposed to one of two cumulative sound exposure levels for 960 pile strikes (217 or 210 dB re 1 µPa(2·s SEL(cum; single strike sound exposure levels of 187 or 180 dB re 1 µPa(2⋅s SEL(ss respectively. This was followed by an immediate assessment of injuries, or assessment 2, 5, or 10 days post-exposure. There were no observed mortalities from the pile driving sound exposure. Fish exposed to 217 dB re 1 µPa(2·s SEL(cum displayed evidence of healing from injuries as post-exposure time increased. Fish exposed to 210 dB re 1 µPa(2·s SEL(cum sustained minimal injuries that were not significantly different from control fish at days 0, 2, and 10. The exposure to 210 dB re 1 µPa(2·s SEL(cum replicated the findings in a previous study that defined this level as the threshold for onset of injury. Furthermore, these data support the hypothesis that one or two Mild injuries resulting from pile driving exposure are unlikely to affect the survival of the exposed animals, at least in a laboratory environment.

  2. Inner Ear Barotrauma After Underwater Pool Competency Training Without the Use of Compressed Air Case and Review.

    Science.gov (United States)

    McIntire, Sean; Boujie, Lee

    2016-01-01

    Inner ear barotrauma can occur when the gas-filled chambers of the ear have difficulty equalizing pressure with the outside environment after changes in ambient pressure. This can transpire even with small pressure changes. Hypobaric or hyperbaric environments can place significant stress on the structures of the middle and inner ear. If methods to equalize pressure between the middle ear and other connected gas-filled spaces (i.e., Valsalva maneuver) are unsuccessful, middle ear overpressurization can occur. This force can be transmitted to the fluid-filled inner ear, making it susceptible to injury. Damage specifically to the structures of the vestibulocochlear system can lead to symptoms of vertigo, hearing loss, and tinnitus. This article discusses the case of a 23-year-old male Marine who presented with symptoms of nausea and gait instability after performing underwater pool competency exercises to a maximum depth of 13 feet, without breathing compressed air. Diagnosis and management of inner ear barotrauma are reviewed, as is differentiation from inner ear decompression sickness. PMID:27450603

  3. Assessment of Barotrauma Resulting from Rapid Decompression of Depth Acclimated Juvenile Chinook Salmon Bearing Radio Telemetry Transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Carlson, Thomas J.; Welch, Abigail E.; Stephenson, John R.; Abernethy, Cary S.; McKinstry, Craig A.; Theriault, Marie-Helene

    2007-09-06

    A multifactor study was conducted by Battelle for the US Army Corps of Engineers to assess the significance of the presence of a radio telemetry transmitter on the effects of rapid decompression from simulated hydro turbine passage on depth acclimated juvenile run-of-the-river Chinook salmon. Study factors were: (1) juvenile chinook salmon age;, subyearling or yearling, (2) radio transmitter present or absent, (3) three transmitter implantation factors: gastric, surgical, and no transmitter, and (4) four acclimation depth factors: 1, 10, 20, and 40 foot submergence equivalent absolute pressure, for a total of 48 unique treatments. Exposed fish were examined for changes in behavior, presence or absence of barotrauma injuries, and immediate or delayed mortality. Logistic models were used to test hypotheses that addressed study objectives. The presence of a radio transmitter was found to significantly increase the risk of barotrauma injury and mortality at exposure to rapid decompression. Gastric implantation was found to present a higher risk than surgical implantation. Fish were exposed within 48 hours of transmitter implantation so surgical incisions were not completely healed. The difference in results obtained for gastric and surgical implantation methods may be the result of study design and the results may have been different if tested fish had completely healed surgical wounds. However, the test did simulate the typical surgical-release time frame for in-river telemetry studies of fish survival so the results are probably representative for fish passing through a turbine shortly following release into the river. The finding of a significant difference in response to rapid decompression between fish bearing radio transmitters and those not implies a bias may exist in estimates of turbine passage survival obtained using radio telemetry. However, the rapid decompression (simulated turbine passage) conditions used for the study represented near worst case exposure

  4. Barodontalgia and barotrauma in the human teeth: findings in navy divers, frogmen, and submariners of the Federal Republic of Germany.

    Science.gov (United States)

    Goethe, W H; Bäter, H; Laban, C

    1989-10-01

    From 2,580 submariners, divers, and frogmen, 13,618 individual findings were evaluated from a total of about 50,000 dental findings of the Nautical Medical Institute of the German Navy, Kiel, West Germany. Trend analysis and statistical significance tests showed that the teeth of navy divers and frogmen had deteriorated very much more within a period of 9 years after their first dental examination than those of submariners. This negative tendency was verified through additional direct comparison between 37 navy divers and 37 submariners whose dental states were observed during a period of 10 years. Here as well, navy divers had significantly worse teeth. The cause of this distinctive dental deterioration among navy divers is probably due to the additional barometric stress they were subjected to for many years during their diving career. Delayed damages as a result of barotrauma may be assumed, a logical suspicion which should be verified by further scientific research. PMID:2515472

  5. Barotrauma: Tooth Under Pressure.

    Science.gov (United States)

    Kumar, Satheesh; Kumar, Preeti Satheesh; John, Jins; Patel, Ruchi

    2015-11-01

    With the growing number of air passengers, flight attendants, leisure pilots, as well as military and airline pilots, dentists may encounter physiological and pathological phenomena precipitated by high altitude. With the introduction of the self-contained breathing apparatus (SCUBA), many of these manifestations caused by changes in atmospheric pressure were reported in association with diving as well. Limited literature exists on this subject. Hence, this article aims to review literature concerning the classification, etiology and manifestations of barodontalgia, as well as important clinical considerations for its management. PMID:26697664

  6. Impact of the use of antibodies anti endothelin 1 on the coronary arterial estenosis for hyperplasia secondary neo intimal to barotraumas with ball and Stent in porcines

    International Nuclear Information System (INIS)

    Coronary angioplasty (PTCA) is performed in about two million surgical procedures every year in the world, and coronary restenosis (CR) continues to be it's weakest point. There are four mechanisms involved in CR 1. Thrombosis, 2.elastic recoil, 3. Constrictive arterial remodeling; and 4. Intimal hyperplasia. The first three are managed with Stents, inhibitors of GP lib//iiia, antiagregants and anticoagulants. The fourth is believed to be the only responsible of post Stent CR. endothelin 1(ET1) produces cellular proliferation. Impact of the anti ET1 anti bodies by intra coronary injection, or generated by immune response at the subcutaneous (SC) application of ET1, on the NI growth in porcines, who have undergone barotrauma with Stent, is expected to be demonstrated. PTCA was performed in 12 pigs (36 arterial specimens). They were sacrificed after four weeks of follow up. Specimens were divided in three groups, previously randomized, resulting in 12 specimens a group. The placebo group received intracoronary infusion of saline solution immediately after the barotraumas. The second group received intracoronary infusion of AET1 antibodies and the third group received SC injection of ET1 fourteen days before the trauma. Segments were studied with IVUS and hystomotphometric analysis. Statistical analysis: it was performed by the student t in order to compare independent measures. Because of the small size of the groups, the Mann Whitney test was applied. A double tale analysis was performed in both cases. A significant reduction of the NI area was obtained both with the injection of AET1 Abs and ET1 SC (p 0.001) in the IVUS and the hystomotphometric analyses. AET1 antibodies seem to prevent the post Stent NI growth. There is no significant advantage between both forms of injection

  7. Barotrauma pulmonar no intra-operatório de procedimento cirúrgico oftalmológico: relato de caso Barotrauma pulmonar en el intraoperatorio de procedimiento quirúrgico oftalmológico: relato de caso Intraoperative pulmonary barotrauma during ophthalmologic surgery: case report

    Directory of Open Access Journals (Sweden)

    Affonso Henrique Zugliani

    2008-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Acidentes anestésicos graves por mau funcionamento de ventiladores mecânicos tornaram-se raros nos tempos atuais. Porém, detalhes técnicos, mesmo em aparelhos de fabricação recente, podem resultar em armadilhas para o anestesiologista e ameaçar a segurança do paciente. O objetivo deste relato de caso foi enfatizar a necessidade de análise criteriosa do material em uso, assim como de detectar e tratar o pneumotórax hipertensivo intra-operatório. RELATO DO CASO: Paciente do sexo feminino, 16 anos, estado físico ASA I, submetida a recobrimento conjuntival de córnea sob anestesia geral. A manutenção foi feita com isoflurano e ventilação controlada mecânica. A anestesia transcorreu sem anormalidades. Na fase final do procedimento cirúrgico, após mobilização do aparelho de anestesia para o início do procedimento de despertar, observou-se quadro de hipóxia, hipotensão arterial e dificuldade ventilatória. Retirados os campos cirúrgicos, evidenciou-se importante enfisema subcutâneo, envolvendo a face, o pescoço e o membro superior. Procedeu-se à troca da cânula traqueal, observando-se a presença de sangue em seu interior. A radiografia de tórax confirmou o diagnóstico de pneumotórax, que foi prontamente drenado. A inspeção no equipamento revelou acotovelamento da mangueira que liga a região inferior do canister ao corpo do aparelho, em função da mobilização do braço articulado, bloqueando o fluxo normal de gases e levando a barotrauma pulmonar. CONCLUSÕES: O pneumotórax hipertensivo durante anestesia geral com ventilação com pressão positiva deve ser sempre um acidente a ser considerado. Múltiplos fatores podem precipitá-lo, o que exige alto grau de suspeição sempre que estiverem envolvidos no ato anestésico-cirúrgico. O equipamento de anestesia deve ser cuidadosamente examinado para que sejam detectadas potenciais causas de acidentes anestésicos.JUSTIFICATIVA Y OBJETIVOS

  8. AFSC/ABL: Rockfish Barotrauma

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Because rockfish (Sebastes spp.) are physoclystic, i.e. their gas bladders are closed off from the gut, they often suffer internal injuries from rapid, internal air...

  9. A CASE OF TENSION PNEUMOPERITONEUM DUE TO COLONIC BAROTRAUMA WITH COMPRESSED AIR

    Directory of Open Access Journals (Sweden)

    Shashidhara

    2014-09-01

    Full Text Available A 23 year old male working in a biscuit factory was brought to emergency department by the coworkers at 4PM with pain abdomen and distension and bleeding per rectum. On further questioning the patient confessed that his co-workers had held him firmly and directed the stream of air from a compressed-air pipeline towards his anal region in the morning. On examination, he was alerting conscious and oriented and tachypneic. The respiratory rate was 30/min, SPO2- 80%, Pulse was 120/min and B.P. 120/80 mm Hg. On palpation, Abdomen was grossly distended (Fig. 1, tense with generalized tenderness and rigidity of abdominal wall. The percussion note was tympanitic and liver dullness obliterated. No free fluid was detected. Bowel sounds were absent. Examination of the perineum did not show any external injury. Rectal examination showed faeces mixed with fresh blood but did not reveal any laceration or perforation in the anal canal or rectum. Straight X-ray abdomen in erect position showed extensive pneumoperitoneum

  10. Esophageal perforation following bite of inner tube of automobile tyre: An unusual cause of barotrauma

    Directory of Open Access Journals (Sweden)

    Kadian Y

    2010-01-01

    Full Text Available An 8-year-old child presented with severe chest pain and respiratory distress after he accidentally bit an automobile tyre tube which burst into his mouth. The chest radiograph revealed left-sided pneumothorax. Both esophagogram and computed tomogram (CT scan revealed a perforation of the distal third of esophagus with extravasation of contrast on left side. The patient was treated conservatively with gastrostomy feeds and antibiotics for 5 weeks with a good response.

  11. Barotrauma pulmonar no intra-operatório de procedimento cirúrgico oftalmológico: relato de caso Barotrauma pulmonar en el intraoperatorio de procedimiento quirúrgico oftalmológico: relato de caso Intraoperative pulmonary barotrauma during ophthalmologic surgery: case report

    OpenAIRE

    Affonso Henrique Zugliani; Flávia Claro; Ana Cláudia C. Mega; Marcelo F. Rodrigues; Gilblainer Ancelmé

    2008-01-01

    JUSTIFICATIVA E OBJETIVOS: Acidentes anestésicos graves por mau funcionamento de ventiladores mecânicos tornaram-se raros nos tempos atuais. Porém, detalhes técnicos, mesmo em aparelhos de fabricação recente, podem resultar em armadilhas para o anestesiologista e ameaçar a segurança do paciente. O objetivo deste relato de caso foi enfatizar a necessidade de análise criteriosa do material em uso, assim como de detectar e tratar o pneumotórax hipertensivo intra-operatório. RELATO DO CASO: Pacie...

  12. Ear Tubes

    Science.gov (United States)

    ... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

  13. Scuba Diving Safety

    Science.gov (United States)

    ... The result is severe dizziness and hearing loss. Pulmonary barotrauma. This condition is the result of improper breathing during the ascent to the surface or, occasionally, from diving with a respiratory tract infection. Symptoms include chest ...

  14. Pro-inflammatory responses in BALB/c and C57BL/6 mice and the role of the Nrf2-amphiregulin axis in ventilator induced lung injury

    OpenAIRE

    Siegl, Stephanie

    2012-01-01

    Patients with acute respiratory distress syndrome (ARDS) normally require mechanical ventilation and are thus at risk for ventilator induced lung injury (VILI). High strain and stress can result in physical injury termed barotrauma/volutrauma and atelectotrauma as well as in exaggerated inflammatory responses termed biotrauma. In the ARDSnet study from the year 2000, which set the current standard of ventilation of ARDS patients, mortality correlated with inflammation, but not with barotrauma...

  15. Pulmonary hemorrhage resulting from bungee jumping.

    Science.gov (United States)

    Manos, Daria; Hamer, Okka; Müller, Nestor L

    2007-11-01

    Pulmonary hemorrhage is a relatively common complication of blunt chest trauma. Occasionally, it may result from pulmonary barotrauma after scuba diving or from sports activities not associated with barotrauma such as long breath-hold diving. We report a case of symmetric diffuse upper lobe hemorrhage resulting from a bungee jump in a previously healthy man. Bungee jumping is an increasingly popular sport with relatively few reported injuries. To our knowledge pulmonary hemorrhage in this setting has not yet been described. PMID:18043394

  16. Shallow Water Diving - The NASA Experience

    Science.gov (United States)

    Fitzpatrick, Daniel; Kelsey-Seybold

    2010-01-01

    This slide presentation reviews some of the problems and solutions that personnel have experienced during sessions in the Neutral Bu0yancy Lab (NBL). It reviews the standard dive that occurs at the NBL, Boyles and Henry's laws as they relate to the effects of diving. It then reviews in depth some of the major adverse physiologic events that happen during a diving session: Ear and Sinus Barotrauma, Decompression Sickness, (DCS), Pulmonary Barotrauma (i.e., Arterial Gas Embolism (AGE). Mediastinal Emphysema, Subcutaneous Emphysema, and Pneumothorax) Oxygen Toxicity and Hypothermia. It includes information about the pulmonary function in NBL divers. Also included is recommendations about flying after diving.

  17. Alveolar hemorrhage after scuba diving: a case report.

    Science.gov (United States)

    Tsai, Ming-Ju; Tsai, Mee-Sun; Tsai, Ying-Ming; Lien, Chi-Tun; Hwang, Jhi-Jhu; Huang, Ming-Shyan

    2010-07-01

    Self-contained underwater breathing apparatus (scuba) diving is increasingly popular in Taiwan. There are few references in the literature regarding pulmonary hemorrhage as the sole manifestation of pulmonary barotrauma in scuba divers, and no study from Taiwan was found in the literature. We present the case of a 25-year-old man who suffered alveolar hemorrhage related to pulmonary barotrauma as a complication of scuba diving. To our knowledge, this is the first case report describing a Taiwanese subject suffering from non-fatal pulmonary hemorrhage after scuba diving. PMID:20638043

  18. Electroporation ablation: A new energy modality for ablation of arrhythmogenic cardiac substrate

    NARCIS (Netherlands)

    van Driel, VJHM

    2016-01-01

    At the very end of the Direct Current (DC) era, low-energy DC ablation was demonstrated to cause myocardial lesions by non-thermal irreversible electroporation (IRE) (permanent formation of pores in the cell membrane, leading to cell death), without arcing and/or barotrauma. To eliminate rather smal

  19. Large sub-pleural air cysts: an extreme form of pulmonary interstitial emphysema

    International Nuclear Information System (INIS)

    Pulmonary interstitial emphysema is a well-documented complication of positive-pressure ventilation. However, the occurrence of large sub-pleural air cysts is a less well-known, extreme manifestation of this entity. We present here an infant who developed this complication of pulmonary barotrauma during cardiopulmonary resuscitative efforts. (orig.)

  20. Barodontalgia.

    Science.gov (United States)

    Zadik, Yehuda

    2009-04-01

    Although considered rare, dentists may encounter oral pain evoked by a change in barometric pressure, a condition known as barodontalgia (aerodontalgia). The article reviews the epidemiology, clinical presentation, pathogenesis, diagnostic process and differential diagnosis (including facial and dental barotrauma) of this phenomenon. Preventive measures are described as well. PMID:19345791

  1. Ear Disorders in Scuba Divers

    Directory of Open Access Journals (Sweden)

    MH Azizi

    2010-12-01

    Full Text Available History of underwater diving dates back to antiquity. Breath-hold technique in diving was known to the ancient nations. However, deep diving progressed only in the early decades of the 19th century as the result of advancements in efficient underwater technologies which subsequently led to invention of sophisticated sets of scuba diving in the 20th century. Currently, diving is performed for various purposes including commercial, recreational, military, underwater construction, oil industry, underwater archeology and scientific assessment of marine life. By increasing popularity of underwater diving, dive-related medical conditions gradually became more evident and created a new challenge for the health care professionals, so that eventually, a specialty the so-called “diving medicine” was established. Most of the diving-associated disorders appear in the head and neck. The most common of all occupational disorders associated with diving are otologic diseases. External otitis has been reported as the most common otolaryngologic problem in underwater divers. Exostosis of the external ear canal may be formed in divers as the result of prolonged diving in cold waters. Other disorders of the ear and paranasal sinuses in underwater divers are caused by barometric pressure change (i.e., barotraumas, and to a lesser extent by decompression sickness. Barotrauma of the middle ear is the most prevalent barotrauma in divers. The inner ear barotraumas, though important, is less common. The present paper is a brief overview of diving-related ear disorders particularly in scuba divers.

  2. Neumotórax hipertensivo por inhalación de cocaína

    Directory of Open Access Journals (Sweden)

    William José González Cogollo

    2002-03-01

    Full Text Available El uso de la cocaína causa complicaciones pulmonares, cardiacas, músculo esqueléticas, obstétricas y gastrointestinales. Se describe el caso de un varón joven quien presento barotrauma (neumotórax hipertensivo posterior a la inhalación de cocaína. Basados en este caso y en una revisión de la literatura medica se recomienda interrogar exhaustivamente acerca del uso de drogas en todo paciente adulto o adolescente con neumotórax "espontáneo".The use of cocaine causes pulmonary, cardiac, obstetric, muskuloskeletal and gastrointestinal complications. The case of a young man who sustained barotrauma (hipertensive pneumotorax associated with the use of cocaine is presentes here. Based on this case and a review of the literature it is recommended that a careful drug abuse history be obtained when "spontaneous" pneumotorax is encountered in an adult or adolescent patient.

  3. Neurological complications of underwater diving.

    Science.gov (United States)

    Rosińska, Justyna; Łukasik, Maria; Kozubski, Wojciech

    2015-01-01

    The diver's nervous system is extremely sensitive to high ambient pressure, which is the sum of atmospheric and hydrostatic pressure. Neurological complications associated with diving are a difficult diagnostic and therapeutic challenge. They occur in both commercial and recreational diving and are connected with increasing interest in the sport of diving. Hence it is very important to know the possible complications associated with this kind of sport. Complications of the nervous system may result from decompression sickness, pulmonary barotrauma associated with cerebral arterial air embolism (AGE), otic and sinus barotrauma, high pressure neurological syndrome (HPNS) and undesirable effect of gases used for breathing. The purpose of this review is to discuss the range of neurological symptoms that can occur during diving accidents and also the role of patent foramen ovale (PFO) and internal carotid artery (ICA) dissection in pathogenesis of stroke in divers. PMID:25666773

  4. A SCUBA diver with acute kidney injury.

    Science.gov (United States)

    Gleeson, Patrick James; Kelly, Yvelynne; Ni Sheaghdha, Eadaoin; Lappin, David

    2015-01-01

    An otherwise healthy young man was transferred to our hospital after a diving incident. He had made an uncontrolled ascent from 10 m. On arrival he appeared well. No hypotensive episodes occurred during the transfer. He denied having arthralgias, back pain, dyspnoea or neurological symptoms. Laboratory investigations revealed acutely elevated creatinine (170 µmol/L) and creatine kinase (909 U/L). Radiology was consistent with a focus of pulmonary barotrauma and intrinsic renal disease. Creatine kinase is a marker of arterial gas embolism (AGE). We determined that our patient suffered acute kidney injury as a result of gas embolisation to his renal vasculature from an area of pulmonary barotrauma. Creatinine fell the following day in response to aggressive intravenous fluids. This is the first reported case of acute kidney injury secondary to AGE. Biochemical studies should be part of the routine assessment of patients involved in diving incidents. PMID:25948841

  5. Facial baroparesis: a critical differential diagnosis for scuba diving accidents--case report.

    Science.gov (United States)

    Iakovlev, E V; Iakovlev, V V

    2014-01-01

    Facial nerve baroparesis is a rare and potentially under-reported complication of scuba diving. A diver, after surfacing from a shallow dive, developed isolated left-sided facial palsy accompanied by pain and decreased hearing in the left ear. No other signs or symptoms attributable to a scuba diving accident were detected. Forty minutes later, he heard a "pop" in the affected ear, after which all symptoms quickly resolved. Repeat neurological and ear examinations were normal. He showed no residual or new symptoms 24 hours later. The differential diagnosis of facial neurological deficit after diving includes decompression sickness, cerebral air embolism due to pulmonary barotrauma, facial nerve barotrauma and common conditions such as stroke and Bell's palsy. It is important to recognize the condition since recompression treatment can further damage the facial nerve. PMID:25558550

  6. Pneumomediastinum or lung damage in breath-hold divers from different mechanisms: a report of three cases.

    Science.gov (United States)

    Toklu, Akin Savaş; Erelel, Mustafa; Arslan, Abdullah

    2013-12-01

    Normally pulmonary over-inflation is not an issue during breath-hold diving, in contrast to lung squeeze. Compared with compressed air diving, pulmonary barotrauma is rare in breath-hold diving. Several mechanisms can lead to an increase in intrathoracic pressure in breath-hold diving that may cause alveolar rupture. Here we report three cases of pulmonary barotrauma in breath-hold diving. Using high-resolution chest tomography, bullous damage in Case 1, and pneumomediastinum in Cases 2 and 3 were detected. Transient neurological symptoms in Cases 1 and 2 suggested cerebral arterial gas embolism. The mechanisms that caused intrapulmonary overpressure were, respectively, lung packing ('buccal pumping'), considerable effort and straining at depth, and breathing compressed air at depth and ascending without exhaling. All three cases recovered without specific treatment such as recompression. PMID:24510331

  7. Pile driving and bioacoustic impacts on fish

    OpenAIRE

    McKee, Deborah C.

    2005-01-01

    How did those of us in the transportation industry suddenly find ourselves in need of knowing about underwater pressure waves and fish barotrauma? On October 17, 1989, a portion of the East Span of the San Francisco Oakland Bay Bridge collapsed. That event was the catalyst for the State of California to institute a comprehensive seismic retrofit program for its bridge structures. The bridge is considered a “vital lifeline structure” to San Francisco. Therefore, the bridge was to be designed t...

  8. The effects of venting and decompression on Yellow Tang (Zebrasoma flavescens) in the marine ornamental aquarium fish trade.

    Science.gov (United States)

    Munday, Emily S; Tissot, Brian N; Heidel, Jerry R; Miller-Morgan, Tim

    2015-01-01

    Each year, over 45 countries export 30 million fish from coral reefs as part of the global marine ornamental aquarium trade. This catch volume is partly influenced by collection methods that cause mortality. Barotrauma in fish resulting from forced ascent from depth can contribute to post-collection mortality. However, implementing decompression stops during ascent can prevent barotrauma. Conversely, venting (puncturing the swim bladder to release expanded internal gas) following ascent can mitigate some signs of barotrauma like positive buoyancy. Here, we evaluate how decompression and venting affect stress and mortality in the Yellow Tang (Zebrasoma flavescens). We examined the effects of three ascent treatments, each with decompression stops of varying frequency and duration, coupled with or without venting, on sublethal effects and mortality using histology and serum cortisol measurements. In fish subjected to ascent without decompression stops or venting, a mean post-collection mortality of 6.2% occurred within 24 h of capture. Common collection methods in the fishery, ascent without decompression stops coupled with venting, or one long decompression stop coupled with venting, resulted in no mortality. Histopathologic examination of heart, liver, head kidney, and swim bladder tissues in fish 0d and 21d post-collection revealed no significant barotrauma- or venting-related lesions in any treatment group. Ascent without decompression stops resulted in significantly higher serum cortisol than ascent with many stops, while venting alone did not affect cortisol. Future work should examine links in the supply chain following collection to determine if further handling and transport stressors affect survivorship and sublethal effects. PMID:25737809

  9. The effects of venting and decompression on Yellow Tang (Zebrasoma flavescens in the marine ornamental aquarium fish trade

    Directory of Open Access Journals (Sweden)

    Emily S. Munday

    2015-02-01

    Full Text Available Each year, over 45 countries export 30 million fish from coral reefs as part of the global marine ornamental aquarium trade. This catch volume is partly influenced by collection methods that cause mortality. Barotrauma in fish resulting from forced ascent from depth can contribute to post-collection mortality. However, implementing decompression stops during ascent can prevent barotrauma. Conversely, venting (puncturing the swim bladder to release expanded internal gas following ascent can mitigate some signs of barotrauma like positive buoyancy. Here, we evaluate how decompression and venting affect stress and mortality in the Yellow Tang (Zebrasoma flavescens. We examined the effects of three ascent treatments, each with decompression stops of varying frequency and duration, coupled with or without venting, on sublethal effects and mortality using histology and serum cortisol measurements. In fish subjected to ascent without decompression stops or venting, a mean post-collection mortality of 6.2% occurred within 24 h of capture. Common collection methods in the fishery, ascent without decompression stops coupled with venting, or one long decompression stop coupled with venting, resulted in no mortality. Histopathologic examination of heart, liver, head kidney, and swim bladder tissues in fish 0d and 21d post-collection revealed no significant barotrauma- or venting-related lesions in any treatment group. Ascent without decompression stops resulted in significantly higher serum cortisol than ascent with many stops, while venting alone did not affect cortisol. Future work should examine links in the supply chain following collection to determine if further handling and transport stressors affect survivorship and sublethal effects.

  10. Cerebral Air Embolism in a Patient with a Tuberculous-Destroyed Lung during Commercial Air Travel: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hyun Seok; Jeong, Hae Woong; In, Hyun Sin [Dept. of Radiology, Pusan Paik Hospital, Inje University School of Medicine, Pusdan (Korea, Republic of)

    2011-08-15

    A cerebral air embolism is a rare cause of stroke, but may occur in patients undergoing invasive cardiac and pulmonary procedures, as well as in divers suffering pulmonary barotrauma from rapid ascent. A cerebral air embolism due to other causes, especially a change of air pressure from air travel, is particularly rare. Here, we report a case of cerebraenr embolism during commercial air travel in a patient with an tuberculous-destroyed lung.

  11. Liquid nitrogen ingestion followed by gastric perforation.

    Science.gov (United States)

    Berrizbeitia, Luis D; Calello, Diane P; Dhir, Nisha; O'Reilly, Colin; Marcus, Steven

    2010-01-01

    Ingestion of liquid nitrogen is rare but carries catastrophic complications related to barotrauma to the gastrointestinal tract. We describe a case of ingestion of liquid nitrogen followed by gastric perforation and respiratory insufficiency and discuss the mechanism of injury and management of this condition. Liquid nitrogen is widely available and is frequently used in classroom settings, in gastronomy, and for recreational purposes. Given the potentially lethal complications of ingestion, regulation of its use, acquisition, and storage may be appropriate. PMID:20065833

  12. The Role of Continuous Positive Airway Pressure Therapy in the Management of Respiratory Distress in Extremely Premature Infants

    OpenAIRE

    Sekar, Kris

    2006-01-01

    The use of mechanical ventilation for the treatment of respiratory distress syndrome (RDS) in low birth weight infants may cause barotrauma, volutrauma, and chronic lung disease. Different continuous positive airway pressure (CPAP) delivery systems exist, each with its own practical and clinical advantages and disadvantages. CPAP can be used as either a primary or an adjunctive respiratory support for RDS. Research demonstrates that CPAP decreases the incidence of respiratory failure after ex...

  13. Unidirectional valve malfunction by the breakage or malposition of disc - two cases report -

    OpenAIRE

    Lee, Chol; Lee, Kyu Chang; Kim, Hye Young; Kim, Mi Na; Choi, Eun Kyung; Kim, Ji-Sub; Lee, Won Sang; Lee, Myeong Jong; Kim, Hyung Tae

    2013-01-01

    Malfunction of the unidirectional valve in a breathing circuit system may cause hypercapnia from the rebreathing of expired gas, ventilation failure, and barotrauma. Capnography is a useful method for monitoring the integrity of the unidirectional valve. We experienced two cases of malfunction of a unidirectional valve which caused leakage and reverse flow, diagnosed early as a change of the capnographic waveform. One case was caused by expiratory unidirectional valve breakage. The other was ...

  14. Can asthmatic subjects dive?

    OpenAIRE

    Yochai Adir; Alfred A. Bove

    2016-01-01

    Recreational diving with self-contained underwater breathing apparatus (scuba) has grown in popularity. Asthma is a common disease with a similar prevalence in divers as in the general population. Due to theoretical concern about an increased risk for pulmonary barotrauma and decompression sickness in asthmatic divers, in the past the approach to asthmatic diver candidates was very conservative, with scuba disallowed. However, experience in the field and data in the current literature do not ...

  15. Fit for high altitude: are hypoxic challenge tests useful?

    OpenAIRE

    Matthys Heinrich

    2011-01-01

    Abstract Altitude travel results in acute variations of barometric pressure, which induce different degrees of hypoxia, changing the gas contents in body tissues and cavities. Non ventilated air containing cavities may induce barotraumas of the lung (pneumothorax), sinuses and middle ear, with pain, vertigo and hearing loss. Commercial air planes keep their cabin pressure at an equivalent altitude of about 2,500 m. This leads to an increased respiratory drive which may also result in symptoms...

  16. Common otolaryngologic problems of flying.

    Science.gov (United States)

    Stewart, T W

    1979-02-01

    Pressure-volume changes associated with changing atmospheric pressure precipitate acute inflammation of the sinus and middle ear cavities, known collectively as barotrauma. Barotitis occurs during descent from high altitudes. A partial vacuum develops, manifested by a retracted tympanic membrane. Hemorrhage may occur as a consequence of the vacuum. Similar pathophysiology causes barosinusitis. While the cause of aerodontalgia is not known, pain in the teeth does occur during ascent rather than descent. PMID:760435

  17. Altered Gene Expression in Cultured Microglia in Response to Simulated Blast Overpressure: Possible Role of Pulse Duration

    OpenAIRE

    Kane, Michael J; Angoa-Pérez, Mariana; Francescutti, Dina M.; Sykes, Catherine E.; Briggs, Denise I.; Leung, Lai Yee; VandeVord, Pamela J.; Kuhn, Donald M.

    2012-01-01

    Blast overpressure has long been known to cause barotrauma to air-filled organs such as lung and middle ear. However, experience in Iraq and Afghanistan is revealing that individuals exposed to explosive munitions can also suffer traumatic brain injury (TBI) even in the absence of obvious external injury. The interaction of a blast shock wave with the brain in the intact cranial vault is extremely complex making it difficult to conclude that a blast wave interacts in a direct manner with the ...

  18. Diving dentistry: a review of the dental implications of scuba diving.

    Science.gov (United States)

    Zadik, Y; Drucker, S

    2011-09-01

    In light of the overwhelming popularity of self-contained underwater breathing apparatus (SCUBA) diving, general dental practitioners should be prepared to address complications arising as a result of diving and to provide patients with accurate information. The aim of this article was to introduce the concepts of diving medicine and dentistry to the dentist, and to supply the dental practitioner with some diagnostic tools as well as treatment guidelines. The literature was reviewed to address diving barotrauma (pressure-induced injury related to an air space) to the head, face and oral regions, as well as scuba mouthpiece-related oral conditions. The relevant conditions for dentists who treat divers include diving-associated headache (migraine, tension-type headache), barosinusitis and barotitis-media (sinus and middle ear barotrauma, respectively), neuropathy, trigeminal (CN V) or facial (CN VII) nerve baroparesis (pressure-induced palsy), dental barotrauma (barometric-related tooth injury), barodontalgia (barometric-related dental pain), mouthpiece-associated herpes infection, pharyngeal gag reflex and temporomandibular joint disorder (dysfunction). For each condition, a theoretical description is followed by practical recommendations for the dental practitioner for the prevention and management of the condition. PMID:21884141

  19. How low can they go when going with the flow? Tolerance of egg and larval fishes to rapid decompression.

    Science.gov (United States)

    Boys, Craig A; Robinson, Wayne; Miller, Brett; Pflugrath, Brett; Baumgartner, Lee J; Navarro, Anna; Brown, Richard; Deng, Zhiqun

    2016-01-01

    Egg and larval fish that drift downstream are likely to encounter river infrastructure and consequently rapid decompression, which may result in significant injury. Pressure-related injury (or barotrauma) has been shown in juvenile fishes when pressure falls sufficiently below that at which the fish has acclimated. There is a presumption that eggs and larvae may be at least as, if not more, susceptible to barotrauma injury because they are far less-developed and more fragile than juveniles, but studies to date report inconsistent results and none have considered the relationship between pressure change and barotrauma over a sufficiently broad range of pressure changes to enable tolerances to be properly determined. To address this, we exposed eggs and larvae of three physoclistic species to rapid decompression in a barometric chamber over a broad range of discrete pressure changes. Eggs, but not larvae, were unaffected by all levels of decompression tested. At exposure pressures below ∼40 kPa, or ∼40% of surface pressure, swim bladder deflation occurred in all species and internal haemorrhage was observed in one species. None of these injuries killed the fish within 24 h, but subsequent mortality cannot be excluded. Consequently, if larval drift is expected where river infrastructure is present, adopting design or operational features which maintain exposure pressures at 40% or more of the pressure to which drifting larvae are acclimated may afford greater protection for resident fishes. PMID:27230649

  20. Respiratory distress syndrome: comparison between radiographic finding after surfactant replacement therapy and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hoon Sik; Kim, Kun Il; Park, Jae Hong [College of Medicine, Pusan National University, Pusan (Korea, Republic of); Jeon, Sung Sook; Kwon, Jeong Mi [Il Sin Christian Hospital, Pusan (Korea, Republic of)

    2000-05-01

    To evaluate the relationship between radiographic findings after surfactant replacement therapy and prognosis in newborns with respiratory distress syndrome (RDs). The chest radiographs and medical records of 78 infants (body weight 840-3600g, mean 1682g, gestational age 20-38 (mean, 31) weeks) who had been treated with surfactant were retrospectively analysed. Surfactant was applied 1-12 (mean, 5) hours after birth. By comparing pre-and post-surfactant radiographs, radiographic changes were graded as either uniform bilateral improvement (grade 1), asymmetrical unilateral improvement (grade 2), or no improvement (grade 3). complications such as barotrauma, bilateral diffuse consolidation, or intracranial hemorrhage were tabulated. We correlated the prognosis with (a) the radiographic improvement pattern, (b) the time of surfactant application, and (c) the incidence of pulmonary complications, respectively. Forty-six (59%) of 78 infants survived, and 32 (41%) died. The survivors comprised 38 infants in group 1 (67%, n=3D57), six in group 1 (46%, n=3D13), and two in group 3 (25%, n=3D8) (p less than 0.05). The survival rate did not correlate with the time of surfactant application (p greater than 0.05). Infants with barotrauma had a lower survival rate (42%, 10/24) than those not suffering from this condition (67%, 36/54) (p less than 0.05). The condition occurred in 12 (21%) of 57 infants in group 1, six (46%) of 13 in group 2, and six (75%) of eight in group 3 (p less than 0.05). Eleven (92%) of 12 infants with pulmonary hemorrhage, seven (100%) of seven with intracranial hemorrhage above grade 3, and seven (41%) of 17 with sepsis died. The radiographic changes occurring after surfactant replacement therapy correlated closely with the incidence of barotrauma and the prognosis of newborns with respiratory distress syndrome. Close observation of follow-up radiographic findings plays an important role in therapy and prognosis. (author)

  1. Survival Predictors for Severe ARDS Patients Treated with Extracorporeal Membrane Oxygenation: A Retrospective Study in China

    Science.gov (United States)

    Liu, Xiaoqing; Xu, Yonghao; Zhang, Rong; Huang, Yongbo; He, Weiqun; Sang, Ling; Chen, Sibei; Nong, Lingbo; Li, Xi; Mao, Pu

    2016-01-01

    Extracorporeal membrane oxygenation (ECMO) is increasingly being applied as life support for acute respiratory distress syndrome (ARDS) patients. However, the outcomes of this procedure have not yet been characterized in severe ARDS patients. The aim of this study was to evaluate the outcomes of severe ARDS patients supported with ECMO and to identify potential predictors of mortality in these patients. A total of 38 severe ARDS patients (aged 51.39±13.27 years, 32 males) who were treated with ECMO in the specialized medical intensive care unit of Guangzhou Institute of Respiratory Diseases from July 2009 to December 2014 were retrospectively reviewed. The clinical data of the patients on the day before ECMO initiation, on the first day of ECMO treatment and on the day of ECMO removal were collected and analyzed. All patients were treated with veno-venous ECMO after a median mechanical ventilation duration of 6.4±7.6 days. Among the 20 patients (52.6%) who were successfully weaned from ECMO, 16 patients (42.1%) survived to hospital discharge. Of the identified pre-ECMO factors, advanced age, a long duration of ventilation before ECMO, a higher Acute Physiology and Chronic Health Evaluation II (APACHE II) score, underlying lung disease, and pulmonary barotrauma prior to ECMO were associated with unsuccessful weaning from ECMO. Furthermore, multiple logistic regression analysis indicated that both barotrauma pre-ECMO and underlying lung disease were independent predictors of hospital mortality. In conclusion, for severe ARDS patients treated with ECMO, barotrauma prior to ECMO and underlying lung disease may be major predictors of ARDS prognosis based on multivariate analysis. PMID:27336170

  2. Respiratory distress syndrome: comparison between radiographic finding after surfactant replacement therapy and prognosis

    International Nuclear Information System (INIS)

    To evaluate the relationship between radiographic findings after surfactant replacement therapy and prognosis in newborns with respiratory distress syndrome (RDs). The chest radiographs and medical records of 78 infants (body weight 840-3600g, mean 1682g, gestational age 20-38 (mean, 31) weeks) who had been treated with surfactant were retrospectively analysed. Surfactant was applied 1-12 (mean, 5) hours after birth. By comparing pre-and post-surfactant radiographs, radiographic changes were graded as either uniform bilateral improvement (grade 1), asymmetrical unilateral improvement (grade 2), or no improvement (grade 3). complications such as barotrauma, bilateral diffuse consolidation, or intracranial hemorrhage were tabulated. We correlated the prognosis with (a) the radiographic improvement pattern, (b) the time of surfactant application, and (c) the incidence of pulmonary complications, respectively. Forty-six (59%) of 78 infants survived, and 32 (41%) died. The survivors comprised 38 infants in group 1 (67%, n=3D57), six in group 1 (46%, n=3D13), and two in group 3 (25%, n=3D8) (p less than 0.05). The survival rate did not correlate with the time of surfactant application (p greater than 0.05). Infants with barotrauma had a lower survival rate (42%, 10/24) than those not suffering from this condition (67%, 36/54) (p less than 0.05). The condition occurred in 12 (21%) of 57 infants in group 1, six (46%) of 13 in group 2, and six (75%) of eight in group 3 (p less than 0.05). Eleven (92%) of 12 infants with pulmonary hemorrhage, seven (100%) of seven with intracranial hemorrhage above grade 3, and seven (41%) of 17 with sepsis died. The radiographic changes occurring after surfactant replacement therapy correlated closely with the incidence of barotrauma and the prognosis of newborns with respiratory distress syndrome. Close observation of follow-up radiographic findings plays an important role in therapy and prognosis. (author)

  3. Neumotórax hipertensivo por inhalación de cocaína

    Directory of Open Access Journals (Sweden)

    William José González Cogollo

    2002-03-01

    Full Text Available El uso de la cocaína causa complicaciones pulmonares, cardiacas, músculo esqueléticas, obstétricas y gastrointestinales. Se describe el caso de un varón joven quien presento barotrauma (neumotórax hipertensivo posterior a la inhalación de cocaína. Basados en este caso y en una revisión de la literatura medica se recomienda interrogar exhaustivamente acerca del uso de drogas en todo paciente adulto o adolescente con neumotórax "espontáneo".

  4. Neumotórax hipertensivo por inhalación de cocaína

    OpenAIRE

    William José González Cogollo

    2002-01-01

    El uso de la cocaína causa complicaciones pulmonares, cardiacas, músculo esqueléticas, obstétricas y gastrointestinales. Se describe el caso de un varón joven quien presento barotrauma (neumotórax hipertensivo) posterior a la inhalación de cocaína. Basados en este caso y en una revisión de la literatura medica se recomienda interrogar exhaustivamente acerca del uso de drogas en todo paciente adulto o adolescente con neumotórax "espontáneo".The use of cocaine causes pulmonary, cardiac, obstetr...

  5. Estudio en un modelo animal neonatal de las maniobras de reclutamiento pulmonar en relación con las alteraciones oximétricas, hemodinámicas, inflamación y estrés oxidativo

    OpenAIRE

    Mendiola de la Osa, Agustín

    2014-01-01

    La maniobra de reclutamiento durante intervenciones quirúrgicas en recién nacidos con pulmón sano podría evitar atelectasias y shunt intrapulmonar. La MR en neonatos durante la anestesia no se realiza rutinariamente. Esta técnica podría originar barotrauma, alteraciones hemodinámicas, inflamación y estrés oxidativo. OBJETIVO: El objetivo de este trabajo es estudiar la repercusión de la MR sobre la mecánica pulmonar, oxigenación, hemodinámica y la producción de inflamación y ...

  6. Reducing Bat Fatalities From Interactions with Operating Wind Turbines (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, M.

    2013-11-01

    One of the biggest advantages of wind energy is that, overall, it has fewer negative impacts on the environment than fossil fuel-generated energy. Most professionals in the wind industry would like to reduce the impact of energy generation on plants, animals, and their habitats. This is why the industry is highly motivated to find out why migrating bats have unexpectedly high fatality rates near operating wind farms. New research has provided quantitative data that indicates barotrauma is not a major cause of bat deaths around operating turbines.

  7. X-ray diagnosis of pneumothorax in intensive care units

    International Nuclear Information System (INIS)

    Pneumothorax is the most severe manifestation of pulmonary barotrauma which occurs in mechanical ventilation. Diagnosis of pneumothorax in intensive care radiology is of particular difficulty. Chest radiographs in supine position show a variety of signs which may be helpful but are not conclusive. There are different techniques for verification of ventrally located pneumothorax. 450 tangential radiographs of the hemithorax in question are most conclusive for demonstration of extrapulmonary air located inside the pleural cavity. This 450 technique is easy to carry out without changing the patients position. (orig.)

  8. Can asthmatic subjects dive?

    Science.gov (United States)

    Adir, Yochai; Bove, Alfred A

    2016-06-01

    Recreational diving with self-contained underwater breathing apparatus (scuba) has grown in popularity. Asthma is a common disease with a similar prevalence in divers as in the general population. Due to theoretical concern about an increased risk for pulmonary barotrauma and decompression sickness in asthmatic divers, in the past the approach to asthmatic diver candidates was very conservative, with scuba disallowed. However, experience in the field and data in the current literature do not support this dogmatic approach. In this review the theoretical risk factors of diving with asthma, the epidemiological data and the recommended approach to the asthmatic diver candidate will be described. PMID:27246598

  9. Cerebral air embolism after pleural streptokinase instillation.

    Science.gov (United States)

    Janisch, Thorsten; Siekmann, Ullrich; Kopp, Rüdger

    2013-12-01

    Iatrogenic pulmonary barotrauma and cerebral arterial gas embolism (CAGE) may complicate a variety of medical procedures, such as certain types of surgery, drug administration through thoracic drainage, pneumoperitoneum, cystoscopy, bronchoscopy, etc. Hyperbaric oxygen treatment following the guidelines for CAGE in diving is the treatment of choice. Pleural streptokinase instillation is a common treatment for parapneumonic pleural effusion and may lead to CAGE. We present such a complication in a 79-year-old woman with a left-sided empyema. Neurological recovery was reasonable, but a left hemiparesis persisted. Prompt treatment of CAGE is necessary to avoid permanent injury and severe disability. PMID:24510333

  10. [Lungs et diving].

    Science.gov (United States)

    Héritier, F; Avanzi, P; Nicod, L

    2014-11-19

    Whilst underwater, the body is submitted to significant variations of the surrounding pressure according to the depth. These conditions modify the hemodynamic and the ventilatory mechanics considerably. Some repercussions, like pulmonary barotrauma, are related to simple physical phenomena. Others, like decompression sickness, are due to more com- plex processes. Breath-hold diving disrupts haematosis and can be complicated by alveolar haemorrhage and loss of consciousness. Acute pulmonary oedema during scuba-diving, breath-hold diving and swimming has been reported more recently. In case of pulmonary disorders scuba-diving is contraindicated most of the time. It is therefore highly recommended to seek medical advice to prevent problems. PMID:25603564

  11. MR Imaging of Subclinical Cerebral Decompression Sickness. A case report

    International Nuclear Information System (INIS)

    Diving accidents related to barotrauma constitute a unique subset of ischemic insults to the central nervous system. Victims may demonstrate components of arterial gas embolism, which has a propensity for cerebral involvement, and/or decompression sickness, with primarily spinal cord involvement. Decompression sickness-related radiology literature is very limited. We present our MR findings including FLAIR images in a decompression sickness patient with atypical presentation and review the related literature. We believe MR can be useful in follow-up studies and in early diagnosis of decompression sickness when symptoms do not fit the classic picture or loss of consciousness in surfacing

  12. Cerebral Arterial Air Embolism Associated with Mechanical Ventilation and Deep Tracheal Aspiration

    OpenAIRE

    Gursoy, S.; Duger, C.; Kaygusuz, K.; Ozdemir Kol, I.; Gurelik, B.; Mimaroglu, C.

    2012-01-01

    Arterial air embolism associated with pulmonary barotrauma has been considered a rare but a well-known complication of mechanical ventilation. A 65-year-old man, who had subarachnoid hemorrhage with Glasgow coma scale of 8, was admitted to intensive care unit and ventilated with the help of mechanical ventilator. Due to the excessive secretions, deep tracheal aspirations were made frequently. GCS decreased from 8–10 to 4-5, and the patient was reevaluated with cranial CT scan. In CT scan, air...

  13. Can asthmatic subjects dive?

    Directory of Open Access Journals (Sweden)

    Yochai Adir

    2016-06-01

    Full Text Available Recreational diving with self-contained underwater breathing apparatus (scuba has grown in popularity. Asthma is a common disease with a similar prevalence in divers as in the general population. Due to theoretical concern about an increased risk for pulmonary barotrauma and decompression sickness in asthmatic divers, in the past the approach to asthmatic diver candidates was very conservative, with scuba disallowed. However, experience in the field and data in the current literature do not support this dogmatic approach. In this review the theoretical risk factors of diving with asthma, the epidemiological data and the recommended approach to the asthmatic diver candidate will be described.

  14. Ocular anomaly in Atlantic midshipman Porichthys plectrodon (Batrachoidiformes: Batrachoididae) from the Mississippi Canyon, north-central Gulf of Mexico.

    Science.gov (United States)

    Womble, M R; Bullard, S A

    2016-02-01

    The first record of an ocular anomaly in Atlantic midshipman Porichthys plectrodon (Batrachoidiformes: Batrachoididae) is reported from a specimen captured in the Mississippi Canyon. The anomalous specimen was bilaterally anophthalmic and the nape and dorsum were darkly pigmented but alizarin staining and histology revealed a complete eye embedded within the cranium beneath a markedly thickened dermal component of the cornea, along with seemingly minor elaboration of the choroid rete between the cornea and lens. Aetiology is indeterminate and beyond the scope of the study materials but barotrauma, infectious disease and previous wounding are doubtful. PMID:26660952

  15. Arterial gas embolism during pressure tolerance testing in a hyperbaric chamber: a report of two cases.

    Science.gov (United States)

    Buschmann, D Kim

    2010-12-01

    This is a report of two cases of arterial gas embolism (AGE) occurring during the course of routine pressure tolerance testing (PTT) of Canadian Forces divers in a dry hyperbaric chamber. PTT is used by many military organizations as a means to determine whether divers can sustain a hyperbaric challenge similar to that to which they will be exposed during their diving duties. Problems arising from such testing are usually limited to issues of equalization and minor otic barotraumas. Incidents of AGE resulting from hyperbaric chamber exposures in general are very unusual. The incidents reported here are the first such cases arising in military divers during PTT to be reported in the extant literature. In one case a potential precipitating pulmonary lesion was identified during post-event chest imaging. In the other case, while presenting with all the usual hallmarks of an AGE, no predisposing pulmonary lesion was identified. Ascent rates were within the limits considered acceptable by the Canadian Forces for PTT. The cases are useful in examining the pathophysiologic mechanisms underlying pulmonary barotrauma and AGE, and raise questions as to the appropriate screening procedures for military divers in this regard. PMID:21197859

  16. Barodontalgia: what have we learned in the past decade?

    Science.gov (United States)

    Zadik, Yehuda

    2010-04-01

    This article reviews the current knowledge regarding barodontalgia, a barometric pressure-related oral (dental and other) pain. Contemporary classification, prevalence, and incidence, features, etiology, and diagnosis of this entity are presented regarding flight and diving conditions. Summarizing the past decade data, three-fourths of episodes were described as severe, sharp, and localized pain. Barodontalgia affects 11.9% of divers and 11.0% of military aircrews with a rate of 5 episodes/1,000 flight-years. Upper and lower dentitions were affected equally in flight, but more upper than lower dentition were affected in diving. The most prevalent etiologic pathologies for in-flight dental pain were faulty dental restorations (including dental barotrauma) and dental caries without pulp involvement (29.2%), necrotic pulp/periapical inflammation (27.8%), vital pulp pathology (13.9%), recent dental treatment (11.1%), and barosinusitis (9.7%). This review refutes 3 generally accepted conventions: According to the results, the current in-flight barodontalgia incidence is similar to the incidence in the first half of the 20th century, the weighted incidence of barodontalgia among aircrews are similar to the weighted incidence among divers, and the role of facial barotrauma in the etiology of in-flight barodontalgia is minor. PMID:20303049

  17. Required treatment margin for coronary endovascular brachytherapy with iridium-192 seed ribbon

    International Nuclear Information System (INIS)

    Purpose: Preliminary clinical trials (SCRIPPS I, WRIST and Gamma 1) employing catheter-based endovascular brachytherapy (EVBT) with iridium-192 (Ir-192) seeds show promising results in reducing restenosis after coronary intervention. Failure analysis of these studies showed a significant number of restenosis at the treatment margin called ''edge effect.'' The objective of this study is to investigate the factors that contribute to the adequacy of treatment margin. Methods and materials: The factors contributing to the margins are penumbra effect at the end of the seed train, uncertainty in target localization, longitudinal seed movement during cardiac cycle and barotrauma due to stent deployment. The magnitudes of the penumbra effect, which refers to the tapering off the prescribed isodose line near the ends of the source train, were calculated for various source lengths of Ir-192 seed ribbon using AAPM TG-43 algorithm. Uncertainty in target localization refers to the fact that the visual estimation of proximal and distal extent of the injury is not accurate, and this can be obtained by comparing the 'estimate' from the interventional cardiologist with careful review of the cine-angiogram. Longitudinal seed movements relative to the coronary vessel during the cardiac cycle were determined by frame-by-frame reviewing cine-angiograms of 30 patients. The proximal and distal source points were measured in reference to branching vessels during the contrast phase of the cine-angiogram. The maximum proximal and distal longitudinal movement was captured and source displacement was measured from the closest proximal and distal branching vessel. Barotrauma, additional injury to the vessel arising from the stent deployment balloon, was obtained by reviewing specifications from commercially available stent delivery systems. Results: The penumbra effect ranges from 3.9 to 4.5 mm for 6-22 Ir-192 seed ribbons. The uncertainty in target localization is within 3 mm for our

  18. PEEP or No PEEP: That Is Not the Question

    Directory of Open Access Journals (Sweden)

    Jesús Villar

    1996-01-01

    Full Text Available Generally, positive end-expiratory pressure (PEEP is applied to improve oxygenation, and has been shown to improve gas exchange and lung compliance in acute lung injury, but it is not without risk. To date, no controlled outcome studies have been published to demonstrate the best method of choosing the level of PEEP. Furthermore, it is not known whether the application of PEEP contributes to lung damage or helps to ameliorate it. The authors review the goals of PEEP and the current evidence on its effects on lung injury and its clinical utility. In the absence of controlled clinical trials, the use of PEEP in acute respiratory distress syndrome needs to be guided by physiological principles that balance the beneficial effects of an increase in functional residual capacity, prevention of alveolar closure, redistribution of lung water and improved ventilation of low ventilation-perfusion areas against the potential harm of alveolar rupture (barotrauma and "volutrauma" and reduction in cardiac output.

  19. A case of pneumothorax due to non-invasive mechanical ventilation

    Directory of Open Access Journals (Sweden)

    İbrahim Koç

    2014-09-01

    Full Text Available Emphysema is enlargement of alveolus, alveolary ducts and destruction of alveolary wall. One of complications of non-invasive mechanical ventilation (NIMV is barotrauma of damaged lung. Here we present a 75 years old male who had Chronic Obstructive Pulmonary Disease (COPD, emphysema for 5 years and suffered from pneumothorax after NIMV. During treatment with NIMV his general condition deteriorated and oxygen saturation decreased immediately. Chest X-ray and tomography revealed pneumothorax. Chest tube inserted under local anesthesia. Although NIMV might seem like innocent, in patients whose general condition immediately worsens, oxygen saturation decreases, has emphysema and bullous lesions pneumothorax must be excluded. J Clin Exp Invest 2014; 5 (3: 469-471

  20. [Neurological decompression illness in a Japanese breath-held diver: a case report].

    Science.gov (United States)

    Matsuo, Ryu; Arakawa, Shuji; Furuta, Yoshihiko; Kanazawa, Yuka; Kamouchi, Masahiro; Kitazono, Takanari

    2012-01-01

    We report a Japanese breath-hold diver (Ama) who presented neurological disorders after diving. He repeated diving into 25-30 meters depth in the sea for 6 hours. After diving, he felt dizziness and unsteady gait. Neurological examination showed left quadrant hemianopia, bilateral limb ataxia and ataxic gait. Head CT revealed gas bubbles in the left parietal lobe. In CT scan on 3 days after onset, gas bubbles disappeared and low density areas were observed in the bilateral parietal lobes. Brain imaging (DWI, T(2)WI and FLAIR) demonstrated high intensity in the parieto-occipital lobes. Neither pulmonary barotrauma nor intracardiac shunt was detected. He was diagnosed as having neurological decompression illness and therefore underwent hyperbaric oxygen therapy. The pathogenesis of this case was considered to be microbubbles induced by decompression. The present case suggests that repetitive rapid surfacing from the deep sea causes neurological decompression illness even in the breath-hold diver. PMID:23064626

  1. The risks of scuba diving: a focus on Decompression Illness.

    Science.gov (United States)

    Hall, Jennifer

    2014-11-01

    Decompression Illness includes both Decompression Sickness (DCS) and Pulmonary Overinflation Syndrome (POIS), subsets of diving-related injury related to scuba diving. DCS is a condition in which gas bubbles that form while diving do not have adequate time to be resorbed or "off-gassed," resulting in entrapment in specific regions of the body. POIS is due to an overly rapid ascent to the surface resulting in the rupture of alveoli and subsequent extravasation of air bubbles into tissue planes or even the cerebral circulation. Divers must always be cognizant of dive time and depth, and be trained in the management of decompression. A slow and controlled ascent, plus proper control of buoyancy can reduce the dangerous consequences of pulmonary barotrauma. The incidence of adverse effects can be diminished with safe practices, allowing for the full enjoyment of this adventurous aquatic sport. PMID:25478296

  2. Arterial gas embolism in a Special Forces combat dive student during free-swimming ascent training: A case study.

    Science.gov (United States)

    Surrett, Gerald W; Vaughan, William M

    2015-01-01

    Free-swimming ascent is taught to military divers and submariners as a self-rescue technique in the event of an emergency or a planned covert surfacing technique. Although this technique is infrequently used, it is considered a high-risk training event due to the risk and subsequent high morbidity and mortality of pulmonary barotrauma from pulmonary over-inflation injury. This case study will illustrate an example of a pulmonary overinflation injury and arterial gas embolism in an Army Special Forces Combat Diver who had no violation of technique while conducting a 50 foot free-swimming ascent to training standards and under the supervision of experienced Dive Supervisors. Additionally, the issue of allowing such individuals to return to diving is discussed. PMID:26094292

  3. Hemoptysis and pneumomediastinum after breath-hold diving in shallow water: a case report.

    Science.gov (United States)

    Henckes, A; Arvieux, J; Cochard, G; Jézéquel, P; Arvieux, C C

    2011-01-01

    We report the case of a healthy 21-year-old woman who performed iterative breath-hold dives in relatively cold water, not exceeding depths of 5 meters but with "empty lungs." At the end of a dive, after experiencing an intense involuntary diaphragmatic contraction underwater, she presented hemoptysis followed by chest pain and cough. Chest radiography and computed tomography were performed 24 hours later, confirming the diagnosis of pneumomediastinum. The clinical course was benign: However, chest pain and effort dyspnea lasted for a few weeks. The pathophysiology of this accident may be explained by a combination of mechanisms involved in several clinical entities, namely pulmonary edema of immersion, pulmonary barotrauma and spontaneous pneumomediastinum. PMID:21721355

  4. Relevance of postmortem radiology to the diagnosis of fatal cerebral gas embolism from compressed air diving

    Science.gov (United States)

    Cole, A J; Griffiths, D; Lavender, S; Summers, P; Rich, K

    2006-01-01

    Aims To test the hypothesis that artefact caused by postmortem off‐gassing is at least partly responsible for the presence of gas within the vascular system and tissues of the cadaver following death associated with compressed air diving. Methods Controlled experiment sacrificing sheep after a period of simulated diving in a hyperbaric chamber and carrying out sequential postmortem computed tomography (CT) on the cadavers. Results All the subject sheep developed significant quantities of gas in the vascular system within 24 hours, as demonstrated by CT and necropsy, while the control animals did not. Conclusions The presence of gas in the vascular system of human cadavers following diving associated fatalities is to be expected, and is not necessarily connected with gas embolism following pulmonary barotrauma, as has previously been claimed. PMID:16489175

  5. "Bong lung" in cystic fibrosis: a case report

    Directory of Open Access Journals (Sweden)

    Hauser Jenny

    2010-11-01

    Full Text Available Abstract Introduction Marijuana or "bong" lung has been recently described. Subjects typically develop large peripheral paraseptal lung bullae and are predisposed to spontaneous pneumothoraces. The underlying mechanism for bullae formation is uncertain, but probably relates to direct lung toxicity and repeated barotrauma as the smoker performs frequent valsalva manoeuvres in an attempt to derive a greater drug effect. Case presentation We describe a case of probable "bong lung" occurring in a 23-year-old Caucasian man with cystic fibrosis who had a history of recurrent pneumothoraces and unusual findings on sputum cytology. Conclusion Our case highlights the importance of questioning young adult cystic fibrosis patients about illicit drug use and the utility of sputum cytology and computed tomography scanning when patients present with pneumothoraces and deteriorations in clinical status.

  6. Oral and maxillofacial aspects of diving medicine.

    Science.gov (United States)

    Brandt, Matthew T

    2004-02-01

    Sport diving has witnessed explosive growth in the past decade, as 8.5 million people are certified in the United States alone. Even though scuba diving is a relatively safe sport, there are serious risks that all divers must consider. Beyond the better-known sequelae such as decompression sickness, middle ear dysfunction, and potential central nervous system effects, scuba diving also carries inherent risk to the maxillofacial region. Atypical facial pain, temporomandibular joint dysfunction, sinus barotraumas, and barodontalgia have all been reported by dentists and physicians treating military, commercial, and sport divers. Additionally, clinicians must address anatomic concerns for would-be divers, including cleft lip and palate, edentulism, or patients with pre-existing temporomandibular dysfunction, midfacial trauma, or craniomaxillofacial surgery. Health care professionals should have a thorough understanding of the implications of scuba diving for consultation and recommendation regarding diving fitness and the treatment of adverse effects of scuba diving to the maxillofacial region. PMID:15040636

  7. [Oral problems in divers].

    Science.gov (United States)

    Scheper, W A; Lobbezoo, F; Eijkman, M A J

    2005-05-01

    Divers can have several oral problems. Firstly, problems caused by pressure changes. These are barodontalgia and odontocrexis. Barodontalgia is toothache by barotrauma. Odontocrexis is restorations coming lose or breaking or tooth fractures by expansion of air beneath restorations. Other problems can occur by cements used to fix casted restorations, by inflammations in the orofacial region, and by not yet fully healed oral wounds. Secondly, there are problems related to the diver's mouthpiece. To keep the mouthpiece in place, the mandible has to be forced in a forward position. Holding this position often and for long periods of time, may develop or aggravate temporomandibular dysfunction. Insufficient fit of the mouthpiece may induce oral mucosal lesions. Therefore, it is recommended to produce individual diver mouthpieces. It is also recommended to produce individual diver mouthpieces for complete dentures wearing divers and for divers with fixed orthodontic appliances. PMID:15932043

  8. Cerebral Arterial Air Embolism Associated with Mechanical Ventilation and Deep Tracheal Aspiration

    Directory of Open Access Journals (Sweden)

    S. Gursoy

    2012-01-01

    Full Text Available Arterial air embolism associated with pulmonary barotrauma has been considered a rare but a well-known complication of mechanical ventilation. A 65-year-old man, who had subarachnoid hemorrhage with Glasgow coma scale of 8, was admitted to intensive care unit and ventilated with the help of mechanical ventilator. Due to the excessive secretions, deep tracheal aspirations were made frequently. GCS decreased from 8–10 to 4-5, and the patient was reevaluated with cranial CT scan. In CT scan, air embolism was detected in the cerebral arteries. The patient deteriorated and spontaneous respiratory activity lost just after the CT investigation. Thirty minutes later cardiac arrest appeared. Despite the resuscitation, the patient died. We suggest that pneumonia and frequent tracheal aspirations are predisposing factors for cerebral vascular air embolism.

  9. Global surgery in a postconflict setting - 5-year results of implementation in the Russian North Caucasus

    Directory of Open Access Journals (Sweden)

    Fatima I. Lunze

    2015-10-01

    Full Text Available Background: Collaborations for global surgery face many challenges to achieve fair and safe patient care and to build sustainable capacity. The 2004 terrorist attack on a school in Beslan in North Ossetia in the Russian North Caucasus left many victims with complex otologic barotrauma. In response, we implemented a global surgery partnership between the Vladikavkaz Children's Hospital, international surgical teams, the North Ossetian Health Ministry, and civil society organizations. This study's aim was to describe the implementation and 5-year results of capacity building for complex surgery in a postconflict, mid-income setting. Design: We conducted an observational study at the Children's Hospital in Vladikavkaz in the autonomous Republic of North Ossetia-Alania, part of the Russian Federation. We assessed the outcomes of 15 initial patients who received otologic surgeries for complex barotrauma resulting from the Beslan terrorism attack and for other indications, and report the incidence of intra- and postoperative complications. Results: Patients were treated for trauma related to terrorism (53% and for indications not related to violence (47%. None of the patients developed peri- or postoperative complications. Three patients (two victims of terrorism who underwent repair of tympanic perforations presented with re-perforations. Four junior and senior surgeons were trained on-site and in Germany to perform and teach similar procedures autonomously. Conclusions: In mid-income, postconflict settings, complex surgery can be safely implemented and achieve patient outcomes comparable to global standards. Capacity building can build on existing resources, such as operation room management, nursing, and anesthesia services. In postconflict environments, substantial surgical burden is not directly attributable to conflict-related injury and disease, but to health systems weakened by conflicts. Extending training and safe surgical care to include

  10. A peculiar blow-out fracture of the inferior orbital wall complicated by extensive subcutaneous emphysema: A case report and review of the literature

    International Nuclear Information System (INIS)

    Blow-out fracture of the orbit is a common injury. However, not many cases are associated with massive subcutaneous emphysema. Even fewer cases are caused by minor trauma or are associated with barotrauma to the orbit due to sneezing, coughing, or vomiting. The authors present a case of blow-out fracture complicated by extensive subcutaneous and mediastinal emphysema that occurred without any obvious traumatic event. A 43-year-old man presented to the Emergency Department with a painful right-sided exophthalmos that he had noticed in the morning immediately after waking up. The patient also complained of diplopia. Physical examination revealed exophthalmos and crepitations suggestive of subcutaneous emphysema. The eye movements, especially upward gaze, were impaired. CT showed blow-out fracture of the inferior orbital wall with a herniation of the orbital soft tissues into the maxillary sinus. There was an extensive subcutaneous emphysema in the head and neck going down to the mediastinum. The patient did not remember any significant trauma to the head that could explain the above mentioned findings. At surgery, an inferior orbital wall fracture with a bony defect of 3×2 centimeter was found and repaired. Blow-out fractures of the orbit are usually a result of a direct trauma caused by an object with a diameter exceeding the bony margins of the orbit. In 50% of cases, they are complicated by orbital emphysema and in 4% of cases by herniation of orbital soft tissues into paranasal sinuses. The occurrence of orbital emphysema without trauma is unusual. In some cases it seems to be related to barotrauma due to a rapid increase in pressure in the upper airways during sneezing, coughing, or vomiting, which very rarely leads to orbital wall fracture. Computed tomography is the most accurate method in detecting and assessing the extent of orbital wall fractures

  11. Global surgery in a postconflict setting - 5-year results of implementation in the Russian North Caucasus

    Science.gov (United States)

    Lunze, Fatima I.; Lunze, Karsten; Tsorieva, Zemfira M.; Esenov, Constantin T.; Reutov, Alexandr; Eichhorn, Thomas; Offergeld, Christian

    2015-01-01

    Background Collaborations for global surgery face many challenges to achieve fair and safe patient care and to build sustainable capacity. The 2004 terrorist attack on a school in Beslan in North Ossetia in the Russian North Caucasus left many victims with complex otologic barotrauma. In response, we implemented a global surgery partnership between the Vladikavkaz Children's Hospital, international surgical teams, the North Ossetian Health Ministry, and civil society organizations. This study's aim was to describe the implementation and 5-year results of capacity building for complex surgery in a postconflict, mid-income setting. Design We conducted an observational study at the Children's Hospital in Vladikavkaz in the autonomous Republic of North Ossetia-Alania, part of the Russian Federation. We assessed the outcomes of 15 initial patients who received otologic surgeries for complex barotrauma resulting from the Beslan terrorism attack and for other indications, and report the incidence of intra- and postoperative complications. Results Patients were treated for trauma related to terrorism (53%) and for indications not related to violence (47%). None of the patients developed peri- or postoperative complications. Three patients (two victims of terrorism) who underwent repair of tympanic perforations presented with re-perforations. Four junior and senior surgeons were trained on-site and in Germany to perform and teach similar procedures autonomously. Conclusions In mid-income, postconflict settings, complex surgery can be safely implemented and achieve patient outcomes comparable to global standards. Capacity building can build on existing resources, such as operation room management, nursing, and anesthesia services. In postconflict environments, substantial surgical burden is not directly attributable to conflict-related injury and disease, but to health systems weakened by conflicts. Extending training and safe surgical care to include specialized

  12. Otological complications associated with hyperbaric oxygen therapy.

    Science.gov (United States)

    Yamamoto, Yoko; Noguchi, Yoshihiro; Enomoto, Mitsuhiro; Yagishita, Kazuyoshi; Kitamura, Ken

    2016-09-01

    The objective of the present study was to clarify the features of otological complications for hyperbaric oxygen therapy (HBOT) and the risk factors for these complications. We enrolled 1115 patients (776 males and 339 females; age 5-89 years) who underwent HBOT. All otological symptoms experienced during HBOT sessions were evaluated, and risk factors were analysed using multivariate logistic regression analysis. Otoscopic findings and interventions for otological complications were assessed in 58 symptomatic patients who visited the Otolaryngology Department. Otological symptoms were experienced by 165 (14.8 %) of the 1115 patients. The multivariate logistic regression analysis identified ages of >60 years and female sex as independent risk factors, whereas patients with sports injuries were at lower risk than those with other primary diseases, except for severe infectious disease. Eighty-two patients (49.7 %) suffered from symptoms at the first HBOT session. The most prevalent symptoms were otalgia (157/165), followed by ear fullness (13/165), hearing loss (12/165) and tinnitus (3/165). One patient experienced vertigo and deterioration of the bone-conduction pure-tone thresholds, suggesting inner ear barotrauma. In 116 ears of the 58 symptomatic patients, abnormal otoscopic findings were recognized in 58 ears (50.0 %). Twenty-seven of the 58 ears required myringotomy or tube insertion, and HBOT was stopped in eight ears in four patients. Of the remaining 58 ears with normal otoscopic findings, 51 received no treatment. Physicians should be aware of both middle and inner ear barotrauma as potential complications of HBOT. PMID:26650550

  13. Threshold for onset of injury in Chinook salmon from exposure to impulsive pile driving sounds.

    Directory of Open Access Journals (Sweden)

    Michele B Halvorsen

    Full Text Available The risk of effects to fishes and other aquatic life from impulsive sound produced by activities such as pile driving and seismic exploration is increasing throughout the world, particularly with the increased exploitation of oceans for energy production. At the same time, there are few data that provide insight into the effects of these sounds on fishes. The goal of this study was to provide quantitative data to define the levels of impulsive sound that could result in the onset of barotrauma to fish. A High Intensity Controlled Impedance Fluid filled wave Tube was developed that enabled laboratory simulation of high-energy impulsive sound that were characteristic of aquatic far-field, plane-wave acoustic conditions. The sounds used were based upon the impulsive sounds generated by an impact hammer striking a steel shell pile. Neutrally buoyant juvenile Chinook salmon (Oncorhynchus tshawytscha were exposed to impulsive sounds and subsequently evaluated for barotrauma injuries. Observed injuries ranged from mild hematomas at the lowest sound exposure levels to organ hemorrhage at the highest sound exposure levels. Frequency of observed injuries were used to compute a biological response weighted index (RWI to evaluate the physiological impact of injuries at the different exposure levels. As single strike and cumulative sound exposure levels (SEL(ss, SEL(cum respectively increased, RWI values increased. Based on the results, tissue damage associated with adverse physiological costs occurred when the RWI was greater than 2. In terms of sound exposure levels a RWI of 2 was achieved for 1920 strikes by 177 dB re 1 µPa(2⋅s SEL(ss yielding a SEL(cum of 210 dB re 1 µPa(2⋅s, and for 960 strikes by 180 dB re 1 µPa(2⋅s SEL(ss yielding a SEL(cum of 210 dB re 1 µPa(2⋅s. These metrics define thresholds for onset of injury in juvenile Chinook salmon.

  14. Threshold for onset of injury in Chinook salmon from exposure to impulsive pile driving sounds.

    Science.gov (United States)

    Halvorsen, Michele B; Casper, Brandon M; Woodley, Christa M; Carlson, Thomas J; Popper, Arthur N

    2012-01-01

    The risk of effects to fishes and other aquatic life from impulsive sound produced by activities such as pile driving and seismic exploration is increasing throughout the world, particularly with the increased exploitation of oceans for energy production. At the same time, there are few data that provide insight into the effects of these sounds on fishes. The goal of this study was to provide quantitative data to define the levels of impulsive sound that could result in the onset of barotrauma to fish. A High Intensity Controlled Impedance Fluid filled wave Tube was developed that enabled laboratory simulation of high-energy impulsive sound that were characteristic of aquatic far-field, plane-wave acoustic conditions. The sounds used were based upon the impulsive sounds generated by an impact hammer striking a steel shell pile. Neutrally buoyant juvenile Chinook salmon (Oncorhynchus tshawytscha) were exposed to impulsive sounds and subsequently evaluated for barotrauma injuries. Observed injuries ranged from mild hematomas at the lowest sound exposure levels to organ hemorrhage at the highest sound exposure levels. Frequency of observed injuries were used to compute a biological response weighted index (RWI) to evaluate the physiological impact of injuries at the different exposure levels. As single strike and cumulative sound exposure levels (SEL(ss), SEL(cum) respectively) increased, RWI values increased. Based on the results, tissue damage associated with adverse physiological costs occurred when the RWI was greater than 2. In terms of sound exposure levels a RWI of 2 was achieved for 1920 strikes by 177 dB re 1 µPa(2)⋅s SEL(ss) yielding a SEL(cum) of 210 dB re 1 µPa(2)⋅s, and for 960 strikes by 180 dB re 1 µPa(2)⋅s SEL(ss) yielding a SEL(cum) of 210 dB re 1 µPa(2)⋅s. These metrics define thresholds for onset of injury in juvenile Chinook salmon. PMID:22745695

  15. Neurally adjusted ventilator assist in very low birth weight infants: Current status.

    Science.gov (United States)

    Narchi, Hassib; Chedid, Fares

    2015-06-26

    Continuous improvements in perinatal care have resulted in increased survival of premature infants. Their immature lungs are prone to injury with mechanical ventilation and this may develop into chronic lung disease (CLD) or bronchopulmonary dysplasia. Strategies to minimize the risk of lung injury have been developed and include improved antenatal management (education, regionalization, steroids, and antibiotics), exogenous surfactant administration and reduction of barotrauma by using exclusive or early noninvasive ventilatory support. The most frequently used mode of assisted ventilation is pressure support ventilation that may lead to patient-ventilator asynchrony that is associated with poor outcome. Ventilator-induced diaphragmatic dysfunction or disuse atrophy of diaphragm fibers may also occur. This has led to the development of new ventilation modes including neurally adjusted ventilatory assist (NAVA). This ventilation mode is controlled by electrodes embedded within a nasogastric catheter which detect the electrical diaphragmatic activity (Edi) and transmit it to trigger the ventilator in synchrony with the patient's own respiratory efforts. This permits the patient to control peak inspiratory pressure, mean airway pressure and tidal volume. Back up pressure control (PC) is provided when there is no Edi signal and no pneumatic trigger. Compared with standard conventional ventilation, NAVA improves blood gas regulation with lower peak inspiratory pressure and oxygen requirements in preterm infants. NAVA is safe mode of ventilation. The majority of studies have shown no significant adverse events in neonates ventilated with NAVA nor a difference in the rate of intraventricular hemorrhage, pneumothorax, or necrotizing enterocolitis when compared to conventional ventilation. Future large size randomized controlled trials should be established to compare NAVA with volume targeted and pressure controlled ventilation in newborns with mature respiratory drive

  16. A comparison of synchronized intermittent mandatory ventilation and pressure-regulated volume control ventilation in elderly patients with acute exacerbations of COPD and respiratory failure

    Directory of Open Access Journals (Sweden)

    Chang SC

    2016-05-01

    Full Text Available Suchi Chang,1 Jindong Shi,2 Cuiping Fu,1 Xu Wu,1 Shanqun Li1 1Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai, 2Department of Respiratory Medicine, The Fifth People’s Hospital of Shanghai, Fudan University, Shanghai, People’s Republic of China Background: COPD is the third leading cause of death worldwide. Acute exacerbations of COPD may cause respiratory failure, requiring intensive care unit admission and mechanical ventilation. Intensive care unit patients with acute exacerbations of COPD requiring mechanical ventilation have higher mortality rates than other hospitalized patients. Although mechanical ventilation is the most effective intervention for these conditions, invasive ventilation techniques have yielded variable effects. Objective: We evaluated pressure-regulated volume control (PRVC ventilation treatment efficacy and preventive effects on pulmonary barotrauma in elderly COPD patients with respiratory failure. Patients and methods: Thirty-nine intubated patients were divided into experimental and control groups and treated with the PRVC and synchronized intermittent mandatory ventilation – volume control methods, respectively. Vital signs, respiratory mechanics, and arterial blood gas analyses were monitored for 2–4 hours and 48 hours. Results: Both groups showed rapidly improved pH, partial pressure of oxygen (PaO2, and PaO2 per fraction of inspired O2 levels and lower partial pressure of carbon dioxide (PaCO2 levels. The pH and PaCO2 levels at 2–4 hours were lower and higher, respectively, in the test group than those in the control group (P<0.05 for both; after 48 hours, blood gas analyses showed no statistical difference in any marker (P>0.05. Vital signs during 2–4 hours and 48 hours of treatment showed no statistical difference in either group (P>0.05. The level of peak inspiratory pressure in the experimental group after mechanical ventilation for 2–4 hours and 48

  17. In situ tagging technique for fishes provides insight into growth and movement of invasive lionfish.

    Science.gov (United States)

    Akins, John L; Morris, James A; Green, Stephanie J

    2014-10-01

    Information on fish movement and growth is primarily obtained through the marking and tracking of individuals with external tags, which are usually affixed to anesthetized individuals at the surface. However, the quantity and quality of data obtained by this method is often limited by small sample sizes owing to the time associated with the tagging process, high rates of tagging-related mortality, and displacement of tagged individuals from the initial capture location. To address these issues, we describe a technique for applying external streamer and dart tags in situ, which uses SCUBA divers to capture and tag individual fish on the sea floor without the use of anesthetic. We demonstrate this method for Indo-Pacific lionfish (Pterois volitans/P. miles), species which are particularly vulnerable to barotrauma when transported to and handled at the surface. To test our method, we tagged 161 individuals inhabiting 26 coral reef locations in the Bahamas over a period of 3 years. Our method resulted in no instances of barotrauma, reduced handling and recovery time, and minimal post-tagging release displacement compared with conventional ex situ tag application. Opportunistic resighting and recapture of tagged individuals reveals that lionfish exhibit highly variable site fidelity, movement patterns, and growth rates on invaded coral reef habitats. In total, 24% of lionfish were resighted between 29 and 188 days after tagging. Of these, 90% were located at the site of capture, while the remaining individuals were resighted between 200 m and 1.1 km from initial site of capture over 29 days later. In situ growth rates ranged between 0.1 and 0.6 mm/day. While individuals tagged with streamer tags posted slower growth rates with increasing size, as expected, there was no relationship between growth rate and fish size for individuals marked with dart tags, potentially because of large effects of tag presence on the activities of small bodied lionfish (i.e., <150

  18. Dynamic changes of pulmonary lesions on CT in patients with severe acute respiratory syndrome treated by non-invasive positive pressure ventilation

    International Nuclear Information System (INIS)

    Objective: To study the dynamic changes of pulmonary lesions of severe acute respiratory syndrome (SARS) treated by non-invasive positive pressure ventilation (NIPPV) on CT. Methods: Serial chest CT images in 18 patients with SARS were retrospectively analyzed before and after NIPPV (4-12 days), and a long-term follow-up (3-36 months) examination by CT was carried out. And 27 SARS cases without NIPPV were enrolled as the control group. Results: (1) There were dynamic changes in 15 cases of 18 cases: partial multilobar consolidations of bilateral lungs changed into ground-glass opacities in 7 of 18 cases, a circular pulmonary emphysema around bronchial vascular strains of the lower lobes was seen in 5 of 18, subpleural pulmonary emphysema was seen in 8 of 18, pulmonary barotraumas were showed in 2 of 18. Residual of subpleural curvilinear shadow related to NIPPV was found in 2 eases on the follow-up scan. (2) Above changes on CT were not found in 27 cases without NIPPV. Conclusion: There were changes of pulmonary lesions of SARS on CT related to NIPPV treatment, It is beneficial to assess the CT images in the NIPPV treatment of the related pneumonia in SARS. (authors)

  19. Submarine tower escape decompression sickness risk estimation.

    Science.gov (United States)

    Loveman, G A M; Seddon, E M; Thacker, J C; Stansfield, M R; Jurd, K M

    2014-01-01

    Actions to enhance survival in a distressed submarine (DISSUB) scenario may be guided in part by knowledge of the likely risk of decompression sickness (DCS) should the crew attempt tower escape. A mathematical model for DCS risk estimation has been calibrated against DCS outcome data from 3,738 exposures of either men or goats to raised pressure. Body mass was used to scale DCS risk. The calibration data included more than 1,000 actual or simulated submarine escape exposures and no exposures with substantial staged decompression. Cases of pulmonary barotrauma were removed from the calibration data. The calibrated model was used to estimate the likelihood of DCS occurrence following submarine escape from the United Kingdom Royal Navy tower escape system. Where internal DISSUB pressure remains at - 0.1 MPa, escape from DISSUB depths 60% DCS risk predicted for a 200-meter escape from saturation at 0.21 MPa. Using the calibrated model to predict DCS for direct ascent from saturation gives similar risk estimates to other published models. PMID:25109085

  20. Diet, ageing and genetic factors in the pathogenesis of diverticular disease

    Institute of Scientific and Technical Information of China (English)

    Daniel Martin Commane; Ramesh Pulendran Arasaradnam; Sarah Mills; John Cummings Mathers; Mike Bradburn

    2009-01-01

    Diverticular disease (DD) is an age-related disorder of the large bowel which may affect half of the population over the age of 65 in the UK. This high prevalence ranks it as one of the most common bowel disorders in western nations. The majority of patients remain asymptomatic but there are sociated life-threatening co-morbidities, which, given the large numbers of people with DD, translates into a considerable number of deaths per annum. Despite this public health burden, relatively little seems to be known about either the mechanisms of development or causality.In the 1970s, a model of DD formulated the concept that diverticula occur as a onsequence of pressureinduced damage to the colon wall amongst those with a low intake of dietary fiber. In this review, we have examined the evidence regarding the influence of ageing, diet,inflammation and genetics on DD development. We argue that the evidence supporting the barotrauma hypothesis is largely anecdotal. We have also identified several gaps in the knowledge base which need to be filled before we can complete a model for the etiology of diverticular disease.

  1. Effects of Tidal Turbine Noise on Fish Task 2.1.3.2: Effects on Aquatic Organisms: Acoustics/Noise - Fiscal Year 2011 - Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    Energy Technology Data Exchange (ETDEWEB)

    Halvorsen, Michele B.; Carlson, Thomas J.; Copping, Andrea E.

    2011-09-30

    Naturally spawning stocks of Chinook salmon (Oncorhynchus tshawytscha) that utilize Puget Sound are listed as threatened (http://www.nwr.noaa.gov/ESA-Salmon-Listings/Salmon-Populations/ Chinook/CKPUG.cfm). Plans exist for prototype tidal turbines to be deployed into their habitat. Noise is known to affect fish in many ways, such as causing a threshold shift in auditory sensitivity or tissue damage. The characteristics of noise, its spectra and level, are important factors that influence the potential for the noise to injure fish. For example, the frequency range of the tidal turbine noise includes the audiogram (frequency range of hearing) of most fish. This study (Effects on Aquatic Organisms, Subtask 2.1.3.2: Acoustics) was performed during FY 2011 to determine if noise generated by a 6-m-diameter open-hydro turbine might affect juvenile Chinook salmon hearing or cause barotrauma. After they were exposed to simulated tidal turbine noise, the hearing of juvenile Chinook salmon was measured and necropsies performed to check for tissue damage. Experimental groups were (1) noise exposed, (2) control (the same handling as treatment fish but without exposure to tidal turbine noise), and (3) baseline (never handled). Preliminary results indicate that low levels of tissue damage may have occurred but that there were no effects of noise exposure on the auditory systems of the test fish.

  2. The Effect of an Externally Attached Neutrally Buoyant Transmitter on Mortal Injury during Simulated Hydroturbine Passage

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Pflugrath, Brett D.; Carlson, Thomas J.; Deng, Zhiqun

    2012-02-03

    On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing through hydroturbines experience a rapid decrease in pressure as they pass by the turbine blade and the severity of this decompression can be highly variable. This rapid decrease in pressure can result in injuries such as swim bladder rupture, exophthalmia, and emboli and hemorrhaging in the fins and tissues. However, recent research indicates that the presence of a telemetry tag (acoustic, radio, inductive) implanted inside the coelom of a juvenile salmon increases the likelihood that the fish will be injured or die during turbine passage. Thus, previous research conducted using telemetry tags implanted into the coelom of fish may have been inaccurate. Thus, a new technique is needed to provide unbiased estimates of survival through turbines. This research provides an evaluation of the effectiveness of a neutrally buoyant externally attached acoustic transmitter. Both nontagged fish and fish tagged with a neutrally buoyant external transmitter were exposed to a range of rapid decompressions simulating turbine passage. Juvenile Chinook salmon tagged with a neutrally buoyant externally attached acoustic transmitter did not receive a higher degree of barotrauma than their nontagged counterparts. We suggest that future research include field-based comparisons of survival and behavior among fish tagged with a neutrally buoyant external transmitter and those internally implanted with transmitters.

  3. Contemporary treatment of children with critical and near-fatal asthma

    Science.gov (United States)

    Shein, Steven L.; Speicher, Richard H.; Filho, José Oliva Proença; Gaston, Benjamin; Rotta, Alexandre T.

    2016-01-01

    Asthma is the most common chronic illness in childhood. Although the vast majority of children with acute asthma exacerbations do not require critical care, some fail to respond to standard treatment and require escalation of support. Children with critical or near-fatal asthma require close monitoring for deterioration and may require aggressive treatment strategies. This review examines the available evidence supporting therapies for critical and near-fatal asthma and summarizes the contemporary clinical care of these children. Typical treatment includes parenteral corticosteroids and inhaled or intravenous beta-agonist drugs. For children with an inadequate response to standard therapy, inhaled ipratropium bromide, intravenous magnesium sulfate, methylxanthines, helium-oxygen mixtures, and non-invasive mechanical support can be used. Patients with progressive respiratory failure benefit from mechanical ventilation with a strategy that employs large tidal volumes and low ventilator rates to minimize dynamic hyperinflation, barotrauma, and hypotension. Sedatives, analgesics and a neuromuscular blocker are often necessary in the early phase of treatment to facilitate a state of controlled hypoventilation and permissive hypercapnia. Patients who fail to improve with mechanical ventilation may be considered for less common approaches, such as inhaled anesthetics, bronchoscopy, and extracorporeal life support. This contemporary approach has resulted in extremely low mortality rates, even in children requiring mechanical support. PMID:27305039

  4. Cocaine-induced pulmonary changes: HRCT findings

    International Nuclear Information System (INIS)

    Objective: To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease. Methods: We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors. Results: In 8 patients (36.4%), the clinical and tomographic findings were consistent with 'crack lung', those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%), barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each. Conclusions: Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings. (author)

  5. Blast Injuries: From Improvised Explosive Device Blasts to the Boston Marathon Bombing.

    Science.gov (United States)

    Singh, Ajay K; Ditkofsky, Noah G; York, John D; Abujudeh, Hani H; Avery, Laura A; Brunner, John F; Sodickson, Aaron D; Lev, Michael H

    2016-01-01

    Although most trauma centers have experience with the imaging and management of gunshot wounds, in most regions blast wounds such as the ones encountered in terrorist attacks with the use of improvised explosive devices (IEDs) are infrequently encountered outside the battlefield. As global terrorism becomes a greater concern, it is important that radiologists, particularly those working in urban trauma centers, be aware of the mechanisms of injury and the spectrum of primary, secondary, tertiary, and quaternary blast injury patterns. Primary blast injuries are caused by barotrauma from the initial increased pressure of the explosive detonation and the rarefaction of the atmosphere immediately afterward. Secondary blast injuries are caused by debris carried by the blast wind and most often result in penetrating trauma from small shrapnel. Tertiary blast injuries are caused by the physical displacement of the victim and the wide variety of blunt or penetrating trauma sustained as a result of the patient impacting immovable objects such as surrounding cars, walls, or fences. Quaternary blast injuries include all other injuries, such as burns, crush injuries, and inhalational injuries. Radiography is considered the initial imaging modality for assessment of shrapnel and fractures. Computed tomography is the optimal test to assess penetrating chest, abdominal, and head trauma. The mechanism of blast injuries and the imaging experience of the victims of the Boston Marathon bombing are detailed, as well as musculoskeletal, neurologic, gastrointestinal, and pulmonary injury patterns from blast injuries. PMID:26761543

  6. Mechanical ventilation for severe asthma.

    Science.gov (United States)

    Leatherman, James

    2015-06-01

    Acute exacerbations of asthma can lead to respiratory failure requiring ventilatory assistance. Noninvasive ventilation may prevent the need for endotracheal intubation in selected patients. For patients who are intubated and undergo mechanical ventilation, a strategy that prioritizes avoidance of ventilator-related complications over correction of hypercapnia was first proposed 30 years ago and has become the preferred approach. Excessive pulmonary hyperinflation is a major cause of hypotension and barotrauma. An appreciation of the key determinants of hyperinflation is essential to rational ventilator management. Standard therapy for patients with asthma undergoing mechanical ventilation consists of inhaled bronchodilators, corticosteroids, and drugs used to facilitate controlled hypoventilation. Nonconventional interventions such as heliox, general anesthesia, bronchoscopy, and extracorporeal life support have also been advocated for patients with fulminant asthma but are rarely necessary. Immediate mortality for patients who are mechanically ventilated for acute severe asthma is very low and is often associated with out-of-hospital cardiorespiratory arrest before intubation. However, patients who have been intubated for severe asthma are at increased risk for death from subsequent exacerbations and must be managed accordingly in the outpatient setting. PMID:26033128

  7. A phase I study of low-pressure hyperbaric oxygen therapy for blast-induced post-concussion syndrome and post-traumatic stress disorder.

    Science.gov (United States)

    Harch, Paul G; Andrews, Susan R; Fogarty, Edward F; Amen, Daniel; Pezzullo, John C; Lucarini, Juliette; Aubrey, Claire; Taylor, Derek V; Staab, Paul K; Van Meter, Keith W

    2012-01-01

    This is a preliminary report on the safety and efficacy of 1.5 ATA hyperbaric oxygen therapy (HBOT) in military subjects with chronic blast-induced mild to moderate traumatic brain injury (TBI)/post-concussion syndrome (PCS) and post-traumatic stress disorder (PTSD). Sixteen military subjects received 40 1.5 ATA/60 min HBOT sessions in 30 days. Symptoms, physical and neurological exams, SPECT brain imaging, and neuropsychological and psychological testing were completed before and within 1 week after treatment. Subjects experienced reversible middle ear barotrauma (5), transient deterioration in symptoms (4), and reversible bronchospasm (1); one subject withdrew. Post-treatment testing demonstrated significant improvement in: symptoms, neurological exam, full-scale IQ (+14.8 points; panxiety (GAD-7: p=0.007), quality of life (MPQoL: p=0.003), and self-report of percent of normal (pexam findings, cognitive testing, and quality-of-life measurements, with concomitant significant improvements in SPECT. PMID:22026588

  8. Neurological disorders and travel.

    Science.gov (United States)

    Awada, Adnan; Kojan, Suleiman

    2003-02-01

    Travel is associated with a number of neurological disorders that can be divided into two categories: (1) Neurological infections including encephalitides, neurotuberculosis, neurobrucellosis, cysticercosis and trichinosis. Some of these disorders can be prevented by vaccinations, such as Japanese B encephalitis and rabies, some by the use of insect repellents and some by avoiding raw milk products and undercooked meat. (2) Non-infective neurological disorders, such as acute mountain sickness and high altitude cerebral oedema, problems occurring during air travel such as syncope, seizures, strokes, nerve compression, barotrauma and vertigo, motion sickness and foodborne neurotoxic disorders such as ciguatera, shellfish poisoning and intoxication by cassava. This group of diseases and disorders could be prevented if the traveller knows about them, applies simple physiological rules, takes some specific medications and knows how to avoid intoxications in certain geographical areas. Meningococcal meningitis, malaria and jet lag syndrome are extensively discussed in other articles of this issue. The discussion in this paper will be limited to the other disorders. PMID:12615385

  9. Intratracheal pulmonary ventilation and congenital diaphragmatic hernia: a report of two cases.

    Science.gov (United States)

    Wilson, J M; Thompson, J R; Schnitzer, J J; Bower, L K; Lillehei, C W; Perlman, N D; Kolobow, T

    1993-03-01

    Previous studies from our institution have shown that neonates with congenital diaphragmatic hernia (CDH), whose best postductal PaO2 (BPDPO2) was less than 100 mm Hg while on maximal conventional mechanical ventilation (CMV), had a mortality exceeding 90%. When combined with extracorporeal membrane oxygenation (ECMO), the mortality rose to 100% in those infants who developed hypercarbia following decannulation. Historically, those patients have required increasing ventilator support, leading to iatrogenic lung damage, and eventual death. Intratracheal pulmonary ventilation (ITPV) using the reverse thrust catheter (RTC) developed by Kolobow incorporates a continuous flow of humidified gas through a reverse Venturi catheter positioned at the distal end of the endotracheal tube. In animal studies, ITPV was shown to result in a reduced physiological dead-space (VD), to facilitate expiration, and to enhance CO2 elimination. In our current study, we have applied ITPV in two neonates with CDH who could not be weaned from ECMO because of uncontrollable hypercapnia, and who met above criteria for 100% mortality. In both cases, ITPV restored normal PaCO2 at low peak inspiratory pressure (PIP) with a substantial decrease in VD. We believe ITPV is suited to ventilating newborns with CDH in whom barotrauma is known to be common. Beyond its present use, ITPV may be useful to ventilate children with other forms of respiratory failure, and should be so considered along with other now available methods of mechanical pulmonary ventilation. PMID:8468666

  10. To-and-for extracorporeal lung assist (ECLA) through a single catheter-in premature goats as an experimental model of infant respiratory Insufficiency.

    Science.gov (United States)

    Tanoue, T; Terasaki, H; Sadanaga, M A; Tsuno, K; Morioka, T

    1988-09-01

    A new to-and-fro V-V bypass extracorporeal lung assist (ECLA) through a single catheter as a blood access was investigated for its efficacy on six premature goats delivered by Cesarean section at a gestational age of 118 approximately 139 days as an experimental model of infant respiratory insufficiency, then applied to a human premature infant suffering from life threatening barotrauma that had developed from mechanical pulmonary ventilation. The extracorporeal bypass flow and the gas flow to the artificial membrane lung were controlled to keep Pa(O)(2) above 40 mmHg and Pa(CO)(2) within normal limits. The neonate's own lungs were treated with a continuous positive airway pressure of 5 approximately 12 cmH(2)O, apneic oxygenation or IMV. Two goats weighing 1250 g and 700 g died 2 approximately 2.5 hours after birth from severe circulatory distress. However, the other four neonates which were heavier than 2000 g, were successfully weaned from ECLA, and three of these could be weaned from mechanical ventilation as well. A human infant also survived and was weaned from ECLA on the third day.(Tanoue T, Terasaki H, Sadanaga M et al.: To-and-fro extracorporeal lung assist (ECLA) through a single catheter-in premature goats as an experimental model of infant respiratory insufficiency. PMID:15236069

  11. SCUBA Diving and Asthma: Clinical Recommendations and Safety.

    Science.gov (United States)

    Coop, Christopher A; Adams, Karla E; Webb, Charles N

    2016-02-01

    The objective of this article is to review the available studies regarding asthma and SCUBA (self-contained underwater breathing apparatus) diving. A literature search was conducted in MEDLINE to identify peer-reviewed articles related to asthma and SCUBA diving using the following keywords: asthma, allergy, and SCUBA diving. SCUBA diving is a popular sport with more than 9 million divers in the USA. SCUBA diving can be a dangerous sport. Bronchospasm can develop in asthmatic patients and cause airway obstruction. Airway obstruction may be localized to the distal airway which prevents gas elimination. Uncontrolled expansion of the distal airway may result in pulmonary barotrauma. There is also the risk of a gas embolism. Asthmatic divers can also aspirate seawater which may induce bronchospasm. Pollen contamination of their oxygen tank may exacerbate atopic asthma in patients. Diving may be hazardous to the lung function of patients with asthma. Despite the risks of SCUBA diving, many asthmatic individuals can dive without serious diving events. Diving evaluations for asthmatic patients have focused on a thorough patient history, spirometry, allergy testing, and bronchial challenges. For patients that wish to dive, their asthma should be well controlled without current chest symptoms. Patients should have a normal spirometry. Some diving societies recommend that an asthmatic patient should successfully pass a bronchial provocation challenge. Recommendations also state that exercise-, emotion-, and cold-induced asthmatics should not dive. Asthmatic patients requiring rescue medication within 48 h should not dive. PMID:25666876

  12. Sublethal effects of catch-and-release fishing: measuring capture stress, fish impairment, and predation risk using a condition index

    Science.gov (United States)

    Campbell, Matthew D.; Patino, Reynaldo; Tolan, J.M.; Strauss, R.E.; Diamond, S.

    2009-01-01

    The sublethal effects of simulated capture of red snapper (Lutjanus campechanus) were analysed using physiological responses, condition indexing, and performance variables. Simulated catch-and-release fishing included combinations of depth of capture and thermocline exposure reflective of environmental conditions experienced in the Gulf of Mexico. Frequency of occurrence of barotrauma and lack of reflex response exhibited considerable individual variation. When combined into a single condition or impairment index, individual variation was reduced, and impairment showed significant increases as depth increased and with the addition of thermocline exposure. Performance variables, such as burst swimming speed (BSS) and simulated predator approach distance (AD), were also significantly different by depth. BSSs and predator ADs decreased with increasing depth, were lowest immediately after release, and were affected for up to 15 min, with longer recovery times required as depth increased. The impairment score developed was positively correlated with cortisol concentration and negatively correlated with both BSS and simulated predator AD. The impairment index proved to be an efficient method to estimate the overall impairment of red snapper in the laboratory simulations of capture and shows promise for use in field conditions, to estimate release mortality and vulnerability to predation.

  13. Fatal diving accidents in western Norway 1983-2007.

    Science.gov (United States)

    Ramnefjell, M P; Morild, I; Mørk, S J; Lilleng, P K

    2012-11-30

    Despite efforts to reduce their number, fatal diving accidents still occur. The circumstances and post-mortem findings in 40 fatal diving accidents in western Norway from 1983 through 2007 were investigated. Diving experience, medical history and toxicology reports were retrieved. The material consisted of recreational divers, professional saturation divers and professional divers without experience with saturation. In 33 cases the diving equipment was examined as part of the forensic investigation. In 27 cases defects in the diving equipment were found. For six divers such defects were responsible for the fatal accidents. Eighteen divers died on the surface or less than 10 m below surface. Five divers reached below 100 msw, and two of them died at this depth. The fatalities were not season-dependent. However, wave-height and strength of currents were influential factors in some cases. Twelve divers were diving alone. Twenty divers had one buddy, 9 of these divers were alone at the time of death. The cause of death was drowning in 31 out of 40 divers; one of them had a high blood-ethanol concentration, in two other divers ethanol was found in the urine, indicating previous ethanol consumption. Nine divers died from sudden decompression, pulmonary barotraumas, underwater trauma and natural causes. The study shows that most of the fatal diving accidents could be avoided if adequate diving safety procedures had been followed. PMID:22981212

  14. Influence of scuba diving on asymptomatic isolated pulmonary bullae.

    Science.gov (United States)

    Germonpré, Peter; Balestra, Costantino; Pieters, Thierry

    2008-12-01

    Pulmonary blebs and bullae are generally considered an absolute contra-indication for scuba diving, because of a high estimated risk of pulmonary overpressure syndrome due to air-trapping inside the bulla. This is primarily based on a number of retrospective studies and case reports; formal prospective evidence of a higher risk is lacking. We present three cases where a pulmonary bulla was radiographically shown to increase in diameter, seemingly related to scuba diving activity, and causing ultimately a barotraumatic diving accident. These cases provide pathophysiological clues as to how even an isolated, non-ventilated bulla can be the cause of pulmonary barotrauma. The most likely mechanism for this phenomenon is a 'stretching' of the bulla upon ascent from the dive: after a period of compression (Boyle's Law), there is a gradual diffusion of air through the bulla wall, with restoration to its initial size by the end of the dive. Upon ascent, the air diffuses only slowly out of the bulla, causing a temporary increase in diameter and stretching of the bulla wall. This repeated stretching causes the bulla to grow gradually. At one point, the cyst wall may become critically thin and rupture during the ascent. PMID:22692754

  15. Pulmonary dysanapsis and diving assessments.

    Science.gov (United States)

    Ong, Lin Min; Bennett, Michael H; Thomas, Paul S

    2009-01-01

    Airway obstruction is a relative contraindication to diving. Dive candidates are assessed clinically, and lung function tests evaluate variables such as forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and the FEV1/FVC ratio. A small number of individuals have a normal FEV1, but a disproportionately large lung capacity, or pulmonary dysanapsis. These individuals have a decreased FEV1/FVC ratio, suggesting airway obstruction, which may affect their dive medical assessments. Three cases of pulmonary dysanapsis presented for fitness-to-dive assessment. Case 1, a 29-year-old male had an FEV1: 3.52 L (85% predicted), FVC: 5.31 L (108.5% predicted), giving a FEV1/FVC of 66%. Case 2, a 25-year-old male with an FEV1: 4.55 L (95% predicted), FVC: 7.0 L (121% predicted) and a FEV1/FVC of 66%. Albuterol produced an FEV1 increase of 11%, but his hypertonic saline challenge was negative. Case 3, a 61-year-old man had an FEV1: 3.49 L (126% predicted), FVC: 7.06 L (216% predicted), and a FEV1/FVC of 49%. This report highlights pulmonary dysanapsis which may be confused with obstructive airway disease and applicants deemed unfit to dive. While pulmonary dysanapsis may increase the risk of airway hyperresponsiveness, there is no evidence of an association with diving-related pulmonary barotrauma. PMID:20112528

  16. [Asthma and scuba diving: can asthmatic patients dive?].

    Science.gov (United States)

    Sade, Kobi; Wiesel, Ory; Kivity, Shmuel; Levo, Yoram

    2007-04-01

    Self-contained underwater breathing apparatus (scuba) diving has grown in popularity, with millions of divers enjoying the sport worldwide. This activity presents unique physical and physiological challenges to the respiratory system, raising numerous concerns about individuals with asthma who choose to dive. Asthma had traditionally been a contraindication to recreational diving, although this caveat has been ignored by large numbers of such patients. Herein we review the currently available literature to provide evidence-based evaluation of the risks associated with diving that are posed to asthmatics. Although there is some indication that asthmatics may be at an increased risk of pulmonary barotrauma, the risk seems to be small. Thus, under the right circumstances, patients with asthma can safely participate in recreational diving without any apparent increased risk of an asthma-related event. Decisions on whether or not diving is hazardous must be made on an individual basis and be founded upon an informed decision shared by both patient and physician. PMID:17476937

  17. Pulmonary function in children after open water SCUBA dives.

    Science.gov (United States)

    Winkler, B E; Tetzlaff, K; Muth, C-M; Hebestreit, H

    2010-10-01

    An increasing number of children and adolescents is diving with Self-Contained Underwater Breathing Apparatus (SCUBA). SCUBA diving is associated with health risks such as pulmonary barotrauma, especially in children and in individuals with airflow limitation. As no data has been published on the effects of open-water diving on pulmonary function in children, the objective of this study was to evaluate the effects of SCUBA dives on airflow in children. 16 healthy children aged 10-13 years underwent spirometry and a cycle-exercise challenge while breathing cold air. They subsequently performed dives to 1-m and 8-m depth in random order. Pulmonary function was measured before and after the exercise challenge and the dives. There were statistically significant decreases in FEV1, FVC, FEV1/FVC, MEF25 and MEF50 after the cold-air exercise challenge and the dives. Changes in lung function following the exercise challenge did not predict the responses to SCUBA diving. In 3 children the post-dive decrements in FEV1 exceeded 10%. These children had a lower body weight and BMI percentile. SCUBA diving in healthy children may be associated with relevant airflow limitation. A low body mass might contribute to diving-associated bronchoconstriction. In the majority of subjects, no clinically relevant airway obstruction could be observed. PMID:20677123

  18. Spontaneous pneumomediastinum in an 11-year-old boy after a shallow breath-hold dive.

    Science.gov (United States)

    Laitila, Maija; Eskola, Vesa

    2013-12-01

    Spontaneous pneumomediastinum is caused by pulmonary barotrauma due to transiently increased intra-alveolar and intra-bronchial pressure. The most frequent triggers of spontaneous pneumomediastinum in children are asthma and manoeuvres creating forced expiration. It has been rarely associated with breath-hold diving. Chest pain and dyspnoea are the main symptoms, and the diagnosis can be confirmed by chest X-ray. The treatment of choice is oxygen, analgesics and monitoring the patient. The recurrence rate is low. The main differential diagnoses of spontaneous pneumomediastinum are oesophageal perforation and pericarditis. We report a case of an 11-year-old boy with no substantial medical history, who tried to breath-hold in shallow water for as long as possible. After diving, he felt dyspnoea and chest pain. Chest X-ray revealed pneumomediastinum and subcutaneous emphysema. The patient was admitted to the PICU for observation and was discharged after two days' follow up. Spontaneous pneumomediastinum in children may be more common than thus far acknowledged. It requires a high index of suspicion and should be considered in all children with acute chest pain. PMID:24510332

  19. Predicting performance in competitive apnea diving. Part III: deep diving.

    Science.gov (United States)

    Schagatay, Erika

    2011-12-01

    The first of these reviews described the physiological factors defining the limits of static apnea, while the second examined performance in apneic distance swimming. This paper reviews the factors determining performance in depth disciplines, where hydrostatic pressure is added to the stressors associated with apnea duration and physical work. Apneic duration is essential for performance in all disciplines, and is prolonged by any means that increases gas storage or tolerance to asphyxia or reduces metabolic rate. For underwater distance swimming, the main challenge is to restrict metabolism despite the work of swimming, and to redirect blood flow to allow the most vital functions. Here, work economy, local tissue energy and oxygen stores, anaerobic capacity of the muscles, and possibly technical improvements will be essential for further development. In the depth disciplines, direct pressure effects causing barotrauma, the narcotic effects of gases, decompression sickness (DCS) and possibly air embolism during ascent need to be taken into account, as does the risk of hypoxia when the dive cannot be rapidly interrupted before the surface is reached again. While in most deep divers apneic duration is not the main limitation thus far, greater depths may call for exceptionally long apneas and slower ascents to avoid DCS. Narcotic effects may also affect the ultimate depth limit, which the divers currently performing 'constant weight with fins' dives predict to be around 156 metres' sea water. To reach these depths, serious physiological challenges have to be met, technical developments needed and safety procedures developed concomitantly. PMID:22183699

  20. Noise exposure under hyperbaric conditions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Objective evidence exists that divers demonstrate a hearing deficit greater than would be expected from ageing effects alone. Deafness in divers may be caused by a number of factors other than exposure to excessive noise levels, eg barotrauma, ear infection etc. This review concentrates on the concern that exposure of commercial divers to noise while at work may cause a hearing deficit. Sound pressure levels recorded both underwater and in diving chambers often exceed those allowable to workers onshore. However, the sound perceived by the diver is modified both in amplitude and in frequency when he is either underwater or in pressurised chambers. Broadly the effect of this modification is to attenuate the sound and thus offer some protection from high noise levels. The degree of attentuation varies with the frequency of the sound, however it is also possible under specific conditions associated with gas density for the sensitivity to particular frequencies to be amplified above that for normal atmospheric air. The levels of sound observed from some underwater tools are of concern even after allowing for a significant de-sensitisation of the divers` hearing. Reports of tinnitus and temporary hearing loss following a dive are sure signs that the noise levels have been harmful. It is not possible at present to describe risk criteria for hearing damage due to noise exposure associated with diving. (author)

  1. Cocaine-induced pulmonary changes: HRCT findings

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Renata Rocha de; Zanetti, Glaucia; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Programa de Pos-Graduacao em Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Petropolis, Petropolis, RJ (Brazil); Souza, Luciana Soares de [Ultra-X, Sao Jose do Rio Preto, SP (Brazil); Silva, Jorge Luiz Pereira e [Universidade Federal da Bahia (UFBA), Salvador (Brazil). Dep. de Medicina e Apoio Diagnostico; Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba (Brazil). Dept. de Clinica Medica; Irion, Klaus Loureiro [Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool (United Kingdom); Mancano, Alexandre Dias [Hospital Anchieta, Taguatinga, DF (Brazil); Nobre, Luiz Felipe [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil); Hochhegger, Bruno [Universidade Federal de Ciencias da Saude de Porto Alegre, Porto Alegre, RS (Brazil); Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2015-07-15

    Objective: To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease. Methods: We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors. Results: In 8 patients (36.4%), the clinical and tomographic findings were consistent with 'crack lung', those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%), barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each. Conclusions: Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings. (author)

  2. Nontraumatic postmortem computed tomographic demonstration of cerebral gas embolism following cardiopulmonary resuscitation

    International Nuclear Information System (INIS)

    The aim of this study was to investigate cerebral gas embolism (GE) on nontraumatic postmortem CT (PMCT), regarding its frequency, location (arterial or venous), and causes. Our subjects were 404 nontraumatically deceased patients who had been in a state of cardiopulmonary arrest on arrival at our emergency room. PMCT was performed within 2 h of the confirmation of death. Cardiopulmonary resuscitation (CPR) was performed on 387 of the 404 subjects; and of these, cerebral GE was detected in 29 (7.5%) subjects (3 arterial, 25 venous, 1 undeterminable). Cerebral GE was not noted in the other 17 of the 404 subjects who did not undergo CPR. However, there was no significant difference in the incidence of cerebral GE between the subjects who underwent CPR and those who did not. The mechanism of cerebral arterial GE was presumed due to pulmonary barotrauma and/or paradoxical embolism, while the thoracic pump theory was suggested to explain the cerebral venous GE. Cerebral arterial/venous GE is found in CPR cases on nontraumatic PMCT. (author)

  3. Cocaine-induced pulmonary changes: HRCT findings

    Directory of Open Access Journals (Sweden)

    Renata Rocha de Almeida

    2015-08-01

    Full Text Available AbstractObjective: To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease.Methods: We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors.Results:In 8 patients (36.4%, the clinical and tomographic findings were consistent with "crack lung", those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%, barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each.Conclusions: Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings.

  4. Differences in regional pulmonary pressure–impedance curves before and after lung injury assessed with a novel algorithm

    International Nuclear Information System (INIS)

    Global pressure–volume (PV) curves are an adjunct measure to describe lung characteristics in patients with acute respiratory distress syndrome (ARDS). There is convincing evidence that high peak inspiratory pressures (PIP) cause barotrauma, while optimized positive end-expiratory pressure (PEEP) helps avoid mechanical injury to the lungs by preventing repeated alveolar opening and closing. The optimal values of PIP and PEEP are deduced from the shape of the PV curve by the identification of so-called lower and upper inflection points. However, it has been demonstrated using electrical impedance tomography (EIT) that the inflection points vary across the lung. This study employs a simple curve-fitting technique to automatically define inflection points on both pressure–volume (PV) and pressure–impedance (PI) curves to asses the differences between global PV and regional PI estimates in animals before and after induced lung injury. The results demonstrate a clear increase in lower inflection point (LIP) along the gravitational axis both before and after lung injury. Moreover, it is clear from comparison of the local EIT-derived LIPs with those derived from global PV curves that a ventilation strategy based on the PV curve alone may leave dependent areas of the lung collapsed. EIT-based PI curve analysis may help choosing an optimal ventilation strategy

  5. The impact of freediving on psychomotor performance and blood catecholamine concentration.

    Science.gov (United States)

    Chmura, Jan; Kawczyński, Adam; Medraś, Marek; Jóźków, Paweł; Morawiec, Bartosz

    2014-01-01

    The aim of the study was to investigate the effects of breath-hold diving on divers' psychomotor performance and blood adrenaline, noradrenaline and lactate concentrations. Four male divers took part in the experiment. During the study the divers' choice reaction time as well as plasma concentration of adrenaline, noradrenaline and lactate were measured. The measurements were carried out before immersion (before a warm-up), three minutes after the dive, and 60 minutes after the dive. A reduction in the reaction time to audiovisual stimuli was found in three divers, three minutes after the dive. Diver 4, who broke his personal best record, had a longer choice reaction time at three minutes after the dive. The adrenaline concentration was lowered in Diver 1 and Diver 2, at three minutes after the dive. The adrenaline level in Diver 3 was relatively steady at all test measurements. In Diver 4, who broke his personal best, a twofold increase in adrenaline concentration was noted at three minutes after the dive. All examined divers revealed an increase in noradrenaline blood level at three minutes after the dive. The results of the study are of great practical value since disturbed reactions during freediving can put the diver at the risk of serious barotraumas. PMID:24851548

  6. Use of dynamic CT in acute respiratory distress syndrome (ARDS) with comparison of positive and negative pressure ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Helm, Emma; Babyn, Paul [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Talakoub, Omid; Alirezaie, Javad [Ryerson University, Department of Electrical and Computer Engineering, Toronto, ON (Canada); Grasso, Francesco; Engelberts, Doreen; Kavanagh, Brian P. [Hospital for Sick Children and the University of Toronto, Departments of Anesthesia and Critical Care Medicine and the Program in Pulmonary and Experimental Medicine, Toronto (Canada)

    2009-01-15

    Negative pressure ventilation via an external device ('iron lung') has the potential to provide better oxygenation with reduced barotrauma in patients with ARDS. This study was designed to see if oxygenation differences between positive and negative ventilation could be explained by CT. Six anaesthetized rabbits had ARDS induced by repeated saline lavage. Rabbits were ventilated with positive pressure ventilation (PPV) and negative pressure ventilation (NPV) in turn. Dynamic CT images were acquired over the respiratory cycle. A computer-aided method was used to segment the lung and calculate the range of CT densities within each slice. Volumes of ventilated lung and atelectatic lung were measured over the respiratory cycle. NPV was associated with an increased percentage of ventilated lung and decreased percentage of atelectatic lung. The most significant differences in ventilation and atelectasis were seen at mid-inspiration and mid-expiration (ventilated lung NPV=61%, ventilated lung PPV=47%, p<0.001; atelectatic lung NPV=10%, atelectatic lung PPV 19%, p<0.001). Aeration differences were not significant at end-inspiration. Dynamic CT can show differences in lung aeration between positive and negative ventilation in ARDS. These differences would not be appreciated if only static breath-hold CT was used. (orig.)

  7. CESAR: conventional ventilatory support vs extracorporeal membrane oxygenation for severe adult respiratory failure

    Directory of Open Access Journals (Sweden)

    Mugford Miranda

    2006-12-01

    Full Text Available Abstract Background An estimated 350 adults develop severe, but potentially reversible respiratory failure in the UK annually. Current management uses intermittent positive pressure ventilation, but barotrauma, volutrauma and oxygen toxicity can prevent lung recovery. An alternative treatment, extracorporeal membrane oxygenation, uses cardio-pulmonary bypass technology to temporarily provide gas exchange, allowing ventilator settings to be reduced. While extracorporeal membrane oxygenation is proven to result in improved outcome when compared to conventional ventilation in neonates with severe respiratory failure, there is currently no good evidence from randomised controlled trials to compare these managements for important clinical outcomes in adults, although evidence from case series is promising. Methods/Design The aim of the randomised controlled trial of Conventional ventilatory support vs extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR is to assess whether, for patients with severe, but potentially reversible, respiratory failure, extracorporeal membrane oxygenation will increase the rate of survival without severe disability ('confined to bed' and 'unable to wash or dress' by six months post-randomisation, and be cost effective from the viewpoints of the NHS and society, compared to conventional ventilatory support. Following assent from a relative, adults (18–65 years with severe, but potentially reversible, respiratory failure (Murray score ≥ 3.0 or hypercapnea with pH Discussion Analysis will be based on intention to treat. A concurrent economic evaluation will also be performed to compare the costs and outcomes of both treatments.

  8. Chest computed tomography in children undergoing extra-corporeal membrane oxygenation: a 9-year single-centre experience

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, Susie J.; Calder, Alistair D. [Great Ormond Street Hospital for Children NHS Foundation Trust, Radiology Department, London (United Kingdom); Randle, Elise; Iguchi, Akane; Brown, Katherine; Hoskote, Aparna [Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiac Intensive Care and ECMO, London (United Kingdom)

    2014-06-15

    We retrospectively reviewed the imaging findings, indications, technique and clinical impact in children who had undergone chest CT while undergoing extra-corporeal membrane oxygenation (ECMO). Radiology and ECMO databases were searched to identify all 19 children who had undergone chest CT (20 scans in total) while on ECMO at our institution between May 2003 and May 2012. We reviewed all CT scans for imaging findings. Chest CT is performed in a minority of children on ECMO (4.5% in our series). Timing of chest CT following commencement of ECMO varied among patient groups but generally it was performed earlier in the neonatal group. Clinically significant imaging findings were found in the majority of chest CT scans. Many scans contained several findings, with most cases demonstrating parenchymal or pleural abnormalities. Case examples illustrate the spectrum of imaging findings, including underlying pathology such as necrotising pneumonia and severe barotrauma, and ECMO-related complications such as tension haemothoraces and cannula migration. The results of chest CT led to a change in patient management in 16 of 19 children (84%). There were no adverse events related to patient transfer. An understanding of scan technique and awareness of potential findings is important for the radiologist to provide prompt and optimal image acquisition and interpretation in appropriate patients. (orig.)

  9. The significance of recurrent lung opacities in neonates on surfactant treatment for respiratory distress syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Odita, J.C. [Dept. of Radiology, Louisiana State Univ. Health Sciences Center, Shreveport (United States)

    2001-02-01

    Purpose. To determine the significance of recurrent opacities in chest radiographs of neonates on surfactant therapy for respiratory distress syndrome (RDS) after an initial period of improvement. Materials and methods. Serial pre- and post-surfactant chest radiographs on 94 preterm infants with RDS were analyzed and the pattern of chest radiographic response was classified as (a) clear, (b) recurrent opacities, and (c) no response. Their clinical characteristics were also recorded. Results. In 34 infants the RDS changes cleared within 3 days. 31 infants developed lung opacities within 10 days after an initial period of improvement. Twenty-nine infants failed to respond to the surfactant. The corresponding mean birth weights for the three groups were 1.74, 1.19, and 0.76 kg and the mean gestation ages 32.6, 27.7, and 25.4 weeks. The incidence of bronchopulmonary dysplasia (BPD) was highest among the slumping infants (72. % vs 50 % in no responders, P < 0.001) Conclusions. The pattern of chest radiographic response is primarily affected by gestation age and birth weight. Recurrent lung opacity after an initial positive response to surfactant therapy may be caused by such factors as edema from barotrauma and patent ductus arteriosus. Infants with intraventricular hemorrhage may demonstrate neurogenic edema. Other contributory factors include pneumonia and abnormal consumption of surfactant. Recurrent lung opacities after surfactant may be a predictor of chronic lung disease in the preterm infant. (orig.)

  10. The significance of recurrent lung opacities in neonates on surfactant treatment for respiratory distress syndrome

    International Nuclear Information System (INIS)

    Purpose. To determine the significance of recurrent opacities in chest radiographs of neonates on surfactant therapy for respiratory distress syndrome (RDS) after an initial period of improvement. Materials and methods. Serial pre- and post-surfactant chest radiographs on 94 preterm infants with RDS were analyzed and the pattern of chest radiographic response was classified as (a) clear, (b) recurrent opacities, and (c) no response. Their clinical characteristics were also recorded. Results. In 34 infants the RDS changes cleared within 3 days. 31 infants developed lung opacities within 10 days after an initial period of improvement. Twenty-nine infants failed to respond to the surfactant. The corresponding mean birth weights for the three groups were 1.74, 1.19, and 0.76 kg and the mean gestation ages 32.6, 27.7, and 25.4 weeks. The incidence of bronchopulmonary dysplasia (BPD) was highest among the slumping infants (72. % vs 50 % in no responders, P < 0.001) Conclusions. The pattern of chest radiographic response is primarily affected by gestation age and birth weight. Recurrent lung opacity after an initial positive response to surfactant therapy may be caused by such factors as edema from barotrauma and patent ductus arteriosus. Infants with intraventricular hemorrhage may demonstrate neurogenic edema. Other contributory factors include pneumonia and abnormal consumption of surfactant. Recurrent lung opacities after surfactant may be a predictor of chronic lung disease in the preterm infant. (orig.)

  11. A reanimação do prematuro extremo em sala de parto: controvérsias Controversies about the resuscitation of extremely preterm infants in the delivery room

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Branco de Almeida

    2005-03-01

    Full Text Available OBJETIVO: Relatar as principais controvérsias quanto aos procedimentos atualmente realizados na reanimação de recém-nascidos de extremo baixo peso na sala de parto. FONTES DOS DADOS: Revisão sistemática dos artigos incluídos em MEDLINE, SciELO e Cochrane Library e dos temas livres publicados em congressos internacionais e nacionais, utilizando-se as palavras-chave reanimação, asfixia e recém-nascido. SÍNTESE DOS DADOS: As principais controvérsias incluem aspectos relacionados à oxigenação e à ventilação do prematuro de extremo baixo peso ao nascimento. Os efeitos da administração de oxigênio em concentrações entre 21% e 100% precisam ser investigados. Os parâmetros adequados de pressão inspiratória, volume pulmonar e pressão expiratória final positiva necessitam ser estabelecidos com a finalidade de minimizar o barotrauma e o volutrauma. Os benefícios da aplicação da pressão positiva contínua de vias aéreas por via nasal também precisam ser bem determinados através de ensaios clínicos randomizados. Além disso, reanimadores manuais devem ser desenvolvidos para otimizar a administração desses parâmetros e minimizar a lesão pulmonar no início da vida extra-uterina. Estudos clínicos sobre a administração ao nascimento de adrenalina, expansores de volume e bicarbonato de sódio são inexistentes em prematuros de muito baixo peso. Adicionalmente, o principal dilema ético envolve a decisão conjunta entre os profissionais e os pais de não iniciar a reanimação na dependência da idade gestacional. CONCLUSÕES: A conduta atualmente vigente poderá ser modificada a partir dos resultados de ensaios clínicos randomizados e controlados, em conjunto com a avaliação do desenvolvimento, realizados em recém-nascidos de extremo baixo peso submetidos à reanimação na sala de parto.OBJECTIVE: To describe the main controversies about resuscitation procedures performed in extremely low birth weight infants in

  12. 护理干预在突发性耳聋患者高压氧治疗中的作用%Effect of nursing intervention on hyperbaric oxygen therapy of patients with sudden deafness

    Institute of Scientific and Technical Information of China (English)

    宋月梅

    2016-01-01

    Objective:To explore the application and effect of nursing intervention on hyperbaric oxygen therapy of patients with sudden deafness.Methods:180 patients with sudden deafness were given drug combined with hyperbaric oxygen therapy and nursing intervention.The effect was observed.Results:53 cases were cured;47 cases were markedly effective;66 cases were effective;14 cases were ineffective;the effective rate was 92.2%.There was no hyperbaric oxygen complications such as middle ear barotrauma.Conclusion:Effective nursing intervention can improve the treatment compliance and clinical curative effect of hyperbaric oxygen therapy in patients with sudden deafness,reduce the incidence of complications,and improve the prognosis of patients.%目的:探讨护理干预在突发性耳聋患者高压氧治疗中的应用及效果。方法:180例突发性耳聋患者给予药物联合高压氧治疗,并给予护理干预,观察其疗效。结果:痊愈53例,显效47例,有效66例,无效14例,有效率92.2%;无中耳气压伤等高压氧并发症发生。结论:有效的护理干预可提高突发性耳聋患者高压氧治疗依从性及临床疗效,减少并发症发生,改善患者预后。

  13. Arterial tree asymmetry reduces cerebral pulsatility.

    Science.gov (United States)

    Vrselja, Zvonimir; Brkic, Hrvoje; Curic, Goran

    2015-11-01

    With each heartbeat, pressure wave (PW) propagates from aorta toward periphery. In cerebral circulation, at the level of circle of Willis (CW), four arteries and four PWs converge. Since the interference is an elemental property of the wave, PWs interfere at the level of CW. We hypothesize that the asymmetry of brain-supplying arteries (that join to form CW) creates phase difference between the four PWs that interfere at the level of CW and reduce downstream cerebral pulsatility. To best of our knowledge, the data about the sequence of PWs' arrival into the cerebral circulation is lacking. Evident imperfect bilateral symmetry of the vessels results with different path length of brain-supplying arteries, hence, PWs should arrive into the head at different times. The probabilistic calculation shows that asynchronous arrival is more probable than synchronous. The importance of PWs for the cerebral circulation is highlighted by the observation that barotrauma protection mechanisms are more influenced by the crest of PW (pulse pressure) than by the mean arterial pressure. In addition, an increased arterial pulsatility is associated with several brain pathologies. We created simple computational models of four converging arteries and found that asynchronous arrival of the PWs results with lower maximum pressure, slower rate of pressure amplification and lower downstream pulsatility. In analogy, the asynchronous arrival of the pressure waves into the cerebral circulation should decrease blood flow pulsatility and lower transmission of kinetic energy on arterial wall. We conclude that asynchronous arrival of PWs into the cerebral circulation influences cerebral hemodynamics and represents a physiological necessity. PMID:26277658

  14. How to mitigate impacts of wind farms on bats? A review of potential conservation measures in the European context

    Energy Technology Data Exchange (ETDEWEB)

    Peste, Filipa, E-mail: filipapeste@gmail.com [Centre for Environmental and Marine Studies (CESAM) (Portugal); Department of Biology, University of Aveiro (Portugal); Paula, Anabela [Bioinsight - Ambiente e Biodiversidade, Lda. Lisboa (Portugal); Silva, Luís P. da [Centre for Environmental and Marine Studies (CESAM) (Portugal); Department of Biology, University of Aveiro (Portugal); MARE and CEF, Department of Life Sciences, University of Coimbra (Portugal); Bernardino, Joana; Pereira, Pedro [Bio3 - Estudos e Projectos em Biologia e Recursos Naturais, Lda. Almada (Portugal); Mascarenhas, Miguel [Bioinsight - Ambiente e Biodiversidade, Lda. Lisboa (Portugal); Costa, Hugo [Bio3 - Estudos e Projectos em Biologia e Recursos Naturais, Lda. Almada (Portugal); Vieira, José; Bastos, Carlos [Department of Electronics, Telecommunications and Informatics / IEETA, University of Aveiro (Portugal); Fonseca, Carlos [Centre for Environmental and Marine Studies (CESAM) (Portugal); Department of Biology, University of Aveiro (Portugal); Pereira, Maria João Ramos [Centre for Environmental and Marine Studies (CESAM) (Portugal); PPGBAN, Department of Zoology, Institute of Biosciences, Federal University of Rio Grande do Sul (Brazil); PPGEC, Federal University of Mato Grosso do Sul (Brazil)

    2015-02-15

    Wind energy is growing worldwide as a source of power generation. Bat assemblages may be negatively affected by wind farms due to the fatality of a significant number of individuals after colliding with the moving turbines or experiencing barotrauma. The implementation of wind farms should follow standard procedures to prevent such negative impacts: avoid, reduce and offset, in what is known as the mitigation hierarchy. According to this approach avoiding impacts is the priority, followed by the minimisation of the identified impacts, and finally, when residual negative impacts still remain, those must be offset or at least compensated. This paper presents a review on conservation measures for bats and presents some guidelines within the compensation scenario, focusing on negative impacts that remain after avoidance and minimisation measures. The conservation strategies presented aim at the improvement of the ecological conditions for the bat assemblage as a whole. While developed under the European context, the proposed measures are potentially applicable elsewhere, taking into consideration the specificity of each region in terms of bat assemblages present, landscape features and policy context regarding nature and biodiversity conservation and management. An analysis of potential opportunities and constraints arising from the implementation of offset/compensation programmes and gaps in the current knowledge is also considered. - Highlights: • Wind energy impacts bat populations in ways not yet fully understood. • As the use of windfarms is growing worldwide greater impacts on bat populations are also expected. • Mitigation hierarchy provides a way to reduce impacts from new wind farm facilities. • Compensation measures may be used to reduce the residual effects on bat populations. • Identify bats ecological needs and compensate according to the existing surroundings.

  15. A field evaluation of an external and neutrally buoyant acoustic transmitter for juvenile salmon: implications for estimating hydroturbine passage survival.

    Directory of Open Access Journals (Sweden)

    Richard S Brown

    Full Text Available Turbine-passed fish are exposed to rapid decreases in pressure which can cause barotrauma. The presence of an implanted telemetry tag increases the likelihood of injury or death from exposure to pressure changes, thus potentially biasing studies evaluating survival of turbine-passed fish. Therefore, a neutrally buoyant externally attached tag was developed to eliminate this bias in turbine passage studies. This new tag was designed not to add excess mass in water or take up space in the coelom, having an effective tag burden of zero with the goal of reducing pressure related biases to turbine survival studies. To determine if this new tag affects fish performance or susceptibility to predation, it was evaluated in the field relative to internally implanted acoustic transmitters (JSATS; Juvenile Salmon Acoustic Telemetry System used widely for survival studies of juvenile salmonids. Survival and travel time through the study reach was compared between fish with either tag type in an area of high predation in the Snake and Columbia rivers, Washington. An additional group of fish affixed with neutrally-buoyant dummy external tags were implanted with passive integrated transponder (PIT tags and recovered further downstream to assess external tag retention and injury. There were no significant differences in survival to the first detection site, 12 river kilometers (rkm downstream of release. Travel times were also similar between groups. Conversely, externally-tagged fish had reduced survival (or elevated tag loss to the second detection site, 65 rkm downstream. In addition, the retention study revealed that tag loss was first observed in fish recaptured approximately 9 days after release. Results suggest that this new tag may be viable for short term (<8 days single-dam turbine-passage studies and under these situations, may alleviate the turbine passage-related bias encountered when using internal tags, however further research is needed to

  16. Clinical trials of an intravenous oxygenator in patients with adult respiratory distress syndrome.

    Science.gov (United States)

    High, K M; Snider, M T; Richard, R; Russell, G B; Stene, J K; Campbell, D B; Aufiero, T X; Thieme, G A

    1992-11-01

    In patients with severe adult respiratory distress syndrome, mechanical ventilation may not be able to ensure gas exchange sufficient to sustain life. We report the use of an intravenous oxygenator (IVOX) in five patients who were suffering from severe adult respiratory distress syndrome as a result of aspiration, fat embolism, or pneumonia. IVOX was used in an attempt to provide supplemental transfer of CO2 and O2 and thereby reduce O2 toxicity and barotrauma. All patients were tracheally intubated, sedated, and chemically paralyzed and had a PaO2 ventilated with an FIO2 = 1.0 and a positive end expiratory pressure of > or = 5 cmH2O. The right common femoral vein was located surgically, and the patient was systemically anticoagulated with heparin. A hollow introducer tube was inserted into the right common femoral vein, and the furled IVOX was passed into the inferior vena cava and advanced until the tip was in the lower portion of the superior vena cava. IVOX use ranged from 2 h to 4 days. In this group of patients, IVOX gas exchange ranged from 21 to 87 ml x min-1 of CO2 and from 28 to 85 ml x min-1 of O2. One of the five patients survived and was discharged from the hospital. The IVOX transferred up to 28% of metabolic gas-exchange requirements. One patient with a small vena cava showed signs of caval obstruction. Three other patients demonstrated signs of a septic syndrome after the device was inserted.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1443737

  17. Impact of breath holding on cardiovascular respiratory and cerebrovascular health.

    Science.gov (United States)

    Dujic, Zeljko; Breskovic, Toni

    2012-06-01

    Human underwater breath-hold diving is a fascinating example of applied environmental physiology. In combination with swimming, it is one of the most popular forms of summer outdoor physical activities. It is performed by a variety of individuals ranging from elite breath-hold divers, underwater hockey and rugby players, synchronized and sprint swimmers, spear fishermen, sponge harvesters and up to recreational swimmers. Very few data currently exist concerning the influence of regular breath holding on possible health risks such as cerebrovascular, cardiovascular and respiratory diseases. A literature search of the PubMed electronic search engine using keywords 'breath-hold diving' and 'apnoea diving' was performed. This review focuses on recent advances in knowledge regarding possibly harmful physiological changes and/or potential health risks associated with breath-hold diving. Available evidence indicates that deep breath-hold dives can be very dangerous and can cause serious acute health problems such a collapse of the lungs, barotrauma at descent and ascent, pulmonary oedema and alveolar haemorrhage, cardiac arrest, blackouts, nitrogen narcosis, decompression sickness and death. Moreover, even shallow apnoea dives, which are far more frequent, can present a significant health risk. The state of affairs is disturbing as athletes, as well as recreational individuals, practice voluntary apnoea on a regular basis. Long-term health risks of frequent maximal breath holds are at present unknown, but should be addressed in future research. Clearly, further studies are needed to better understand the mechanisms related to the possible development or worsening of different clinical disorders in recreational or competitive breath holding and to determine the potential changes in training/competition regimens in order to prevent these adverse events. PMID:22574634

  18. Neurology and diving.

    Science.gov (United States)

    Massey, E Wayne; Moon, Richard E

    2014-01-01

    Diving exposes a person to the combined effects of increased ambient pressure and immersion. The reduction in pressure when surfacing can precipitate decompression sickness (DCS), caused by bubble formation within tissues due to inert gas supersaturation. Arterial gas embolism (AGE) can also occur due to pulmonary barotrauma as a result of breath holding during ascent or gas trapping due to disease, causing lung hyperexpansion, rupture and direct entry of alveolar gas into the blood. Bubble disease due to either DCS or AGE is collectively known as decompression illness. Tissue and intravascular bubbles can induce a cascade of events resulting in CNS injury. Manifestations of decompression illness can vary in severity, from mild (paresthesias, joint pains, fatigue) to severe (vertigo, hearing loss, paraplegia, quadriplegia). Particularly as these conditions are uncommon, early recognition is essential to provide appropriate management, consisting of first aid oxygen, targeted fluid resuscitation and hyperbaric oxygen, which is the definitive treatment. Less common neurologic conditions that do not require hyperbaric oxygen include rupture of a labyrinthine window due to inadequate equalization of middle ear pressure during descent, which can precipitate vertigo and hearing loss. Sinus and middle ear overpressurization during ascent can compress the trigeminal and facial nerves respectively, causing temporary facial hypesthesia and lower motor neuron facial weakness. Some conditions preclude safe diving, such as seizure disorders, since a convulsion underwater is likely to be fatal. Preventive measures to reduce neurologic complications of diving include exclusion of individuals with specific medical conditions and safe diving procedures, particularly related to descent and ascent. PMID:24365363

  19. The physiology and pathophysiology of human breath-hold diving.

    Science.gov (United States)

    Lindholm, Peter; Lundgren, Claes E G

    2009-01-01

    This is a brief overview of physiological reactions, limitations, and pathophysiological mechanisms associated with human breath-hold diving. Breath-hold duration and ability to withstand compression at depth are the two main challenges that have been overcome to an amazing degree as evidenced by the current world records in breath-hold duration at 10:12 min and depth of 214 m. The quest for even further performance enhancements continues among competitive breath-hold divers, even if absolute physiological limits are being approached as indicated by findings of pulmonary edema and alveolar hemorrhage postdive. However, a remarkable, and so far poorly understood, variation in individual disposition for such problems exists. Mortality connected with breath-hold diving is primarily concentrated to less well-trained recreational divers and competitive spearfishermen who fall victim to hypoxia. Particularly vulnerable are probably also individuals with preexisting cardiac problems and possibly, essentially healthy divers who may have suffered severe alternobaric vertigo as a complication to inadequate pressure equilibration of the middle ears. The specific topics discussed include the diving response and its expression by the cardiovascular system, which exhibits hypertension, bradycardia, oxygen conservation, arrhythmias, and contraction of the spleen. The respiratory system is challenged by compression of the lungs with barotrauma of descent, intrapulmonary hemorrhage, edema, and the effects of glossopharyngeal insufflation and exsufflation. Various mechanisms associated with hypoxia and loss of consciousness are discussed, including hyperventilation, ascent blackout, fasting, and excessive postexercise O(2) consumption. The potential for high nitrogen pressure in the lungs to cause decompression sickness and N(2) narcosis is also illuminated. PMID:18974367

  20. Fit for high altitude: are hypoxic challenge tests useful?

    Directory of Open Access Journals (Sweden)

    Matthys Heinrich

    2011-02-01

    Full Text Available Abstract Altitude travel results in acute variations of barometric pressure, which induce different degrees of hypoxia, changing the gas contents in body tissues and cavities. Non ventilated air containing cavities may induce barotraumas of the lung (pneumothorax, sinuses and middle ear, with pain, vertigo and hearing loss. Commercial air planes keep their cabin pressure at an equivalent altitude of about 2,500 m. This leads to an increased respiratory drive which may also result in symptoms of emotional hyperventilation. In patients with preexisting respiratory pathology due to lung, cardiovascular, pleural, thoracic neuromuscular or obesity-related diseases (i.e. obstructive sleep apnea an additional hypoxic stress may induce respiratory pump and/or heart failure. Clinical pre-altitude assessment must be disease-specific and it includes spirometry, pulsoximetry, ECG, pulmonary and systemic hypertension assessment. In patients with abnormal values we need, in addition, measurements of hemoglobin, pH, base excess, PaO2, and PaCO2 to evaluate whether O2- and CO2-transport is sufficient. Instead of the hypoxia altitude simulation test (HAST, which is not without danger for patients with respiratory insufficiency, we prefer primarily a hyperoxic challenge. The supplementation of normobaric O2 gives us information on the acute reversibility of the arterial hypoxemia and the reduction of ventilation and pulmonary hypertension, as well as about the efficiency of the additional O2-flow needed during altitude exposure. For difficult judgements the performance of the test in a hypobaric chamber with and without supplemental O2-breathing remains the gold standard. The increasing numbers of drugs to treat acute pulmonary hypertension due to altitude exposure (acetazolamide, dexamethasone, nifedipine, sildenafil or to other etiologies (anticoagulants, prostanoids, phosphodiesterase-5-inhibitors, endothelin receptor antagonists including mechanical aids to

  1. Audiovestibular manifestations in patients with ankylosing spondylitis.

    Science.gov (United States)

    Amor-Dorado, Juan C; Barreira-Fernandez, Maria P; Vazquez-Rodriguez, Tomas R; Gomez-Acebo, Ines; Miranda-Filloy, Jose A; Diaz de Teran, Teresa; Llorca, Javier; Gonzalez-Gay, Miguel A

    2011-03-01

    Ankylosing spondylitis (AS) is a chronic inflammatory disease of unknown origin affecting up to 1% of the population. Little is known about audiovestibular impairment in patients with AS, especially the presence of cochleovestibular dysfunction in these patients. To investigate audiovestibular manifestations in AS, we studied a series of 50 consecutive patients who fulfilled the modified New York diagnostic criteria for AS and 44 matched controls. Individuals with history of cardiovascular disease, cerebrovascular complications, peripheral artery disease, renal insufficiency, syphilis, Meniere and other vestibular syndromes, infections involving the inner ear, barotrauma, or in treatment with ototoxic drugs were excluded. Most patients with AS were men (80%). The mean age at the time of study was 52.5 years, and mean age at the onset of symptoms was 34.4 years. Twenty-nine (58%) patients showed abnormal hearing loss in the audiogram compared to only 8 (18%) controls (p < 0.001). Values of audiometric tests (pure-tone average and speech reception threshold) yielded significant differences between patients and controls (p < 0.001). It is noteworthy that the audiogram shape disclosed a predominant pattern of high-frequency sensorineural hearing loss in AS patients (50%) compared to controls (18%) (p = 0.002). Also, AS patients exhibited abnormal vestibular tests more commonly than controls. AS patients had an increased frequency of head-shaking nystagmus (20%) compared to controls (0%) (p < 0.001). Moreover, patients (26%) showed a significantly increased frequency of abnormal caloric test compared to controls (0%) (p < 0.001). Finally, a significantly increased frequency of abnormal clinical test of sensory integration and balance with a predominant vestibular loss pattern was observed in patients (36%) compared to controls (5%) (p < 0.001). In conclusion, the current study demonstrates strong evidence for inner ear compromise in patients with AS. PMID:21358443

  2. Traumatic lung injury attributed to tornadic activity-induced barometric pressure changes in two dogs.

    Science.gov (United States)

    Cichocki, Brandy N; Dugat, Danielle R; Snider, Timothy A

    2016-06-01

    CASE DESCRIPTION A 7-year-old castrated male Italian Greyhound (dog 1) and an approximately 1-year-old female Labrador Retriever (dog 2) were evaluated because of respiratory distress 8 and 10 days, respectively, after a tornado. CLINICAL FINDINGS No obvious external injuries were identified auscultation revealed decreased bronchovesicular sounds in the affected hemithorax of both dogs. Clinicopathologic changes were mild, with evidence of inflammation in both dogs. Thoracic radiography of both dogs revealed pneumothorax and pleural effusion with effacement of the diaphragm; findings on CT included severe pulmonary atelectasis of affected lung lobes with normal bronchial tree configurtion and no evidence of diaphragmatic hernia. TREATMENT AND OUTCOME Exploratory thoracotomy of both dogs confirmed CT findings Pulmonary parenchymal damage consistent with a large rupture was found in both patients. A large hematoma was adhered to the ruptured lung lobe of dog 1. Grossly affected lung tissue was removed; histologic examination revealed atelectasis, pulmonary fib osis, thrombosis, and minimal (dog 1) to marked (dog 2) inflammation Microbial culture of lung tissue yielded no growth for dog 1 and Streptococcus spp and Escherichia coli susceptible to amoxicillin-clavulanic acid for dog 2. Dog 1 had a recurrence of pneumothorax treated by drainage with a thoracostomy tube 1 month after surgery. Eighteen months after surgery, both dogs were reportedly doing well. CLINICAL RELEVANCE Development of clinical signs after a tornado, together with clinical, diagnostic imaging, surgical, and histologic findings led to a presumptive diagnosis of pulmonary barotrauma for both dogs. Long-term outcome for these dogs, treated at a referral hospital, was good. PMID:27172344

  3. Differential effects of superoxide and hydrogen peroxide on myogenic signaling, membrane potential, and contractions of mouse renal afferent arterioles.

    Science.gov (United States)

    Li, Lingli; Lai, En Yin; Wellstein, Anton; Welch, William J; Wilcox, Christopher S

    2016-06-01

    Myogenic contraction is the principal component of renal autoregulation that protects the kidney from hypertensive barotrauma. Contractions are initiated by a rise in perfusion pressure that signals a reduction in membrane potential (Em) of vascular smooth muscle cells to activate voltage-operated Ca(2+) channels. Since ROS have variable effects on myogenic tone, we investigated the hypothesis that superoxide (O2 (·-)) and H2O2 differentially impact myogenic contractions. The myogenic contractions of mouse isolated and perfused single afferent arterioles were assessed from changes in luminal diameter with increasing perfusion pressure (40-80 mmHg). O2 (·-), H2O2, and Em were assessed by fluorescence microscopy during incubation with paraquat to increase O2 (·-) or with H2O2 Paraquat enhanced O2 (·-) generation and myogenic contractions (-42 ± 4% vs. -19 ± 4%, P < 0.005) that were blocked by SOD but not by catalase and signaled via PKC. In contrast, H2O2 inhibited the effects of paraquat and reduced myogenic contractions (-10 ± 1% vs. -19 ± 2%, P < 0.005) and signaled via PKG. O2 (·-) activated Ca(2+)-activated Cl(-) channels that reduced Em, whereas H2O2 activated Ca(2+)-activated and voltage-gated K(+) channels that increased Em Blockade of voltage-operated Ca(2+) channels prevented the enhanced myogenic contractions with paraquat without preventing the reduction in Em Myogenic contractions were independent of the endothelium and largely independent of nitric oxide. We conclude that O2 (·-) and H2O2 activate different signaling pathways in vascular smooth muscle cells linked to discreet membrane channels with opposite effects on Em and voltage-operated Ca(2+) channels and therefore have opposite effects on myogenic contractions. PMID:27053691

  4. Causes of bat fatalities at wind turbines: Hypotheses and predictions

    Science.gov (United States)

    Cryan, P.M.; Barclay, R.M.R.

    2009-01-01

    Thousands of industrial-scale wind turbines are being built across the world each year to meet the growing demand for sustainable energy. Bats of certain species are dying at wind turbines in unprecedented numbers. Species of bats consistently affected by turbines tend to be those that rely on trees as roosts and most migrate long distances. Although considerable progress has been made in recent years toward better understanding the problem, the causes of bat fatalities at turbines remain unclear. In this synthesis, we review hypothesized causes of bat fatalities at turbines. Hypotheses of cause fall into 2 general categoriesproximate and ultimate. Proximate causes explain the direct means by which bats die at turbines and include collision with towers and rotating blades, and barotrauma. Ultimate causes explain why bats come close to turbines and include 3 general types: random collisions, coincidental collisions, and collisions that result from attraction of bats to turbines. The random collision hypothesis posits that interactions between bats and turbines are random events and that fatalities are representative of the bats present at a site. Coincidental hypotheses posit that certain aspects of bat distribution or behavior put them at risk of collision and include aggregation during migration and seasonal increases in flight activity associated with feeding or mating. A surprising number of attraction hypotheses suggest that bats might be attracted to turbines out of curiosity, misperception, or as potential feeding, roosting, flocking, and mating opportunities. Identifying, prioritizing, and testing hypothesized causes of bat collisions with wind turbines are vital steps toward developing practical solutions to the problem. ?? 2009 American Society of Mammalogists.

  5. How to mitigate impacts of wind farms on bats? A review of potential conservation measures in the European context

    International Nuclear Information System (INIS)

    Wind energy is growing worldwide as a source of power generation. Bat assemblages may be negatively affected by wind farms due to the fatality of a significant number of individuals after colliding with the moving turbines or experiencing barotrauma. The implementation of wind farms should follow standard procedures to prevent such negative impacts: avoid, reduce and offset, in what is known as the mitigation hierarchy. According to this approach avoiding impacts is the priority, followed by the minimisation of the identified impacts, and finally, when residual negative impacts still remain, those must be offset or at least compensated. This paper presents a review on conservation measures for bats and presents some guidelines within the compensation scenario, focusing on negative impacts that remain after avoidance and minimisation measures. The conservation strategies presented aim at the improvement of the ecological conditions for the bat assemblage as a whole. While developed under the European context, the proposed measures are potentially applicable elsewhere, taking into consideration the specificity of each region in terms of bat assemblages present, landscape features and policy context regarding nature and biodiversity conservation and management. An analysis of potential opportunities and constraints arising from the implementation of offset/compensation programmes and gaps in the current knowledge is also considered. - Highlights: • Wind energy impacts bat populations in ways not yet fully understood. • As the use of windfarms is growing worldwide greater impacts on bat populations are also expected. • Mitigation hierarchy provides a way to reduce impacts from new wind farm facilities. • Compensation measures may be used to reduce the residual effects on bat populations. • Identify bats ecological needs and compensate according to the existing surroundings

  6. Lesão brônquica e pneumotórax após reintubação usando um cateter para troca da via aérea Lesión brónquica y neumotórax posterior a la reintubación usando un catéter para el cambio de la vía aérea Bronchial injury and pneumothorax after reintubation using an airway exchange catheter

    Directory of Open Access Journals (Sweden)

    Juliano P. de Almeida

    2013-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Relatamos um caso de pneumotórax causado por perfuração brônquica durante uma reintubação usando um cateter para troca da via aérea (CTVA em um paciente com câncer de cabeça e pescoço. RELATO DE CASO: Paciente do sexo masculino, 53 anos, com carcinoma de orofaringe, foi internado na UTI com pneumonia grave e síndrome da angústia respiratória aguda (SARA. O paciente foi identificado como sendo de difícil intubação e uma sonda endotraqueal (SET foi inserida através de um broncoscópio. Após uma semana de tratamento, observou-se ruptura do manguito endotraqueal. A troca da sonda endotraqueal foi necessária para obter uma ventilação pulmonar satisfatória. Um cateter para troca da via aérea (Cook, tamanho 14 foi usado para realizar a reintubação. Depois da reintubação, o paciente apresentou piora na saturação de oxigênio e uma radiografia revelou um grande pneumotórax. Um dreno torácico foi inserido e uma melhora imediata na saturação de oxigênio foi observada. A repetição da radiografia confirmou o posicionamento correto do dreno torácico e a reexpansão do pulmão direito. A broncoscopia realizada mostrou uma laceração posterior do brônquio principal direito. O paciente foi extubado no dia seguinte. Depois de quatro dias, o dreno torácico foi removido. A radiografia realizada um dia depois da retirada do dreno revelou um pequeno pneumotórax no lobo superior direito, mas o paciente permaneceu assintomático. CONCLUSÕES: O cateter para troca da via aérea é uma ferramenta valiosa para lidar com pacientes difíceis de intubar. Embora os médicos geralmente concentrem sua atenção em evitar um barotrauma causado pelo suplemento de oxigênio ou ventilação a jato através do CTVA, a preocupação com a técnica de inserção pode minimizar as complicações que ameaçam a vida e aumentar a segurança do CTVA.JUSTIFICATIVA Y OBJETIVOS: Relatamos aquí un caso de neumotórax causado

  7. Effects of Tidal Turbine Noise on Fish Hearing and Tissues - Draft Final Report - Environmental Effects of Marine and Hydrokinetic Energy

    Energy Technology Data Exchange (ETDEWEB)

    Halvorsen, Michele B.; Carlson, Thomas J.; Copping, Andrea E.

    2011-09-30

    Snohomish Public Utility District No.1 plans to deploy two 6 meter OpenHydro tidal turbines in Admiralty Inlet in Puget Sound, under a FERC pilot permitting process. Regulators and stakeholders have raised questions about the potential effect of noise from the turbines on marine life. Noise in the aquatic environment is known to be a stressor to many types of aquatic life, including marine mammals, fish and birds. Marine mammals and birds are exceptionally difficult to work with for technical and regulatory reasons. Fish have been used as surrogates for other aquatic organisms as they have similar auditory structures. This project was funded under the FY09 Funding Opportunity Announcement (FOA) to Snohomish PUD, in partnership with the University of Washington - Northwest National Marine Renewable Energy Center, the Sea Mammal Research Unit, and Pacific Northwest National Laboratory. The results of this study will inform the larger research project outcomes. Proposed tidal turbine deployments in coastal waters are likely to propagate noise into nearby waters, potentially causing stress to native organisms. For this set of experiments, juvenile Chinook salmon (Oncorhynchus tshawytscha) were used as the experimental model. Plans exist for prototype tidal turbines to be deployed into their habitat. Noise is known to affect fish in many ways, such as causing a threshold shift in auditory sensitivity or tissue damage. The characteristics of noise, its spectra and level, are important factors that influence the potential for the noise to injure fish. For example, the frequency range of the tidal turbine noise includes the audiogram (frequency range of hearing) of most fish. This study was performed during FY 2011 to determine if noise generated by a 6-m diameter OpenHydro turbine might affect juvenile Chinook salmon hearing or cause barotrauma. Naturally spawning stocks of Chinook salmon that utilize Puget Sound are listed as threatened (http://www.nwr.noaa

  8. [Hyperbaric therapy and diving medicine - diving medicine - present state and prospects].

    Science.gov (United States)

    Winkler, Bernd; Muth, Claus-Martin; Piepho, Tim

    2015-10-01

    The diving accident (decompression incident, DCI) occurs in the decompression phase of dives. The DCI can either be caused by an arterial gas embolism (AGE) subsequent to a pulmonary barotrauma or by the formation of inert gas bubbles subsequent to a reduction of ambient pressure during the ascent from depth. In contrast to the traditional assumption that decompression incidents only occur if decompression rules are neglected, recent data indicate that a vast amount of diving accidents occur even though divers adhered to the rules. Hence, there is a large inter- and intraindividual variability in the predisposition for diving accidents. Within the past few years, the molecular understanding of the pathophysiology of diving accidents has improved considerably. It is now well accepted that pro-inflammatory and pro-coagulatory mechanisms play a central role. Moreover, microparticles are increasingly discussed in the pathogenesis of diving accidents. These new molecular findings have not yet resulted in new therapeutic approaches. However, new approaches of preconditioning before the dive have been developed which are intended to reduce the risk of diving accidents. The symptoms of a diving accident show a large variability and range. They reach from pruritus over tension in the female breast, marbled skin and pain in the joints to severe neurological disability like paraplegia or hemiplegia. Furthermore, pulmonary symptoms can be a result of a pulmonary gas embolism and/or a tension pneumothorax. Extreme cases can also manifest as generalized, difficult-to-treat seizures, loss of consciousness or even death. The evidence-based therapy of diving accidents consists of an immediate application of 100% inspiratory O2. This can be performed via a demand valve, face mask with reservoir bag or ventilation bag connected to a reservoir bag. Fluid substitution is performed by i. v. infusion of 500-1000ml/h of cristalloids. If consciousness is not impaired, the diver is

  9. Relato de caso: anestesia em paciente portador de distrofia torácica asfixiante: Síndrome de Jeune

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    Deise Saletti

    2012-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Síndrome de Jeune, ou Distrofia Torácica Asfixiante, é uma doença autossômica recessiva. Esta síndrome é caracterizada por uma displasia óssea com variadas anormalidades: torácica, pancreática, cardíaca, hepática, renal e da retina. A idade em que o quadro clínico dos pacientes se apresenta está correlacionada com a gravidade da doença. Esses pacientes apresentam policondrodistrofia com costelas largas, curtas, horizontais e junções costocondrais irregulares levando a uma caixa torácica rígida e reduzida com grau de injúria respiratória variado. RELATO DO CASO: Paciente do sexo masculino, 4 meses, 7 kg, portador de Distrofia Torácica Asfixiante. Apresentava-se intubado e com caixa torácica reduzida. Ecocardiograma: hipertensão pulmonar leve. Tomografia de tórax: hipoplasia pulmonar. Submetido à toracoplastia bilateral e toracotomia sob anestesia geral. Manutenção da anestesia: infusão contínua de sufentanil e sevoflurano. Parâmetros ventilatórios: ventilação mecânica ciclada à pressão. Com a abertura do tórax, houve melhora dos parâmetros ventilatórios e, após o posicionamento da prótese torácica, observou-se limitação ventilatória. Decidiu-se pela diminuição da prótese torácica com consequente melhora da ventilação. CONCLUSÕES: É imprescindível o diagnóstico de todas as anormalidades presentes para o correto manejo anestésico. Foi necessária observação para adequar ventilação pré- e pós-toracotomia/toracoplastia e para manter o paciente hemodinamicamente estável. A forma mais adequada para ventilação mecânica é a ciclada à pressão para vencer a barreira mecânica. No intraoperatório, é desejável manter o pico de pressão inspiratória o mais baixo possível para minimizar o risco de barotrauma, de impedimento do retorno venoso e diminuição do débito cardíaco.

  10. Lesão brônquica e pneumotórax após reintubação usando um cateter para troca da via aérea

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    Juliano P. de Almeida

    2013-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Relatamos um caso de pneumotórax causado por perfuração brônquica durante uma reintubação usando um cateter para troca da via aérea (CTVA em um paciente com câncer de cabeça e pescoço. RELATO DE CASO: Paciente do sexo masculino, 53 anos, com carcinoma de orofaringe, foi internado na UTI com pneumonia grave e síndrome da angústia respiratória aguda (SARA. O paciente foi identificado como sendo de difícil intubação e uma sonda endotraqueal (SET foi inserida através de um broncoscópio. Após uma semana de tratamento, observou-se ruptura do manguito endotraqueal. A troca da sonda endotraqueal foi necessária para obter uma ventilação pulmonar satisfatória. Um cateter para troca da via aérea (Cook, tamanho 14 foi usado para realizar a reintubação. Depois da reintubação, o paciente apresentou piora na saturação de oxigênio e uma radiografia revelou um grande pneumotórax. Um dreno torácico foi inserido e uma melhora imediata na saturação de oxigênio foi observada. A repetição da radiografia confirmou o posicionamento correto do dreno torácico e a reexpansão do pulmão direito. A broncoscopia realizada mostrou uma laceração posterior do brônquio principal direito. O paciente foi extubado no dia seguinte. Depois de quatro dias, o dreno torácico foi removido. A radiografia realizada um dia depois da retirada do dreno revelou um pequeno pneumotórax no lobo superior direito, mas o paciente permaneceu assintomático. CONCLUSÕES: O cateter para troca da via aérea é uma ferramenta valiosa para lidar com pacientes difíceis de intubar. Embora os médicos geralmente concentrem sua atenção em evitar um barotrauma causado pelo suplemento de oxigênio ou ventilação a jato através do CTVA, a preocupação com a técnica de inserção pode minimizar as complicações que ameaçam a vida e aumentar a segurança do CTVA.

  11. Effects of pressure-controlled and volume-controlled ventilation on respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.

    Science.gov (United States)

    Sen, Oznur; Umutoglu, Tarik; Aydın, Nurdan; Toptas, Mehmet; Tutuncu, Ayse Cigdem; Bakan, Mefkur

    2016-01-01

    Pressure-controlled ventilation (PCV) is less frequently employed in general anesthesia. With its high and decelerating inspiratory flow, PCV has faster tidal volume delivery and different gas distribution. The same tidal volume setting, delivered by PCV versus volume-controlled ventilation (VCV), will result in a lower peak airway pressure and reduced risk of barotrauma. We hypothesized that PCV instead of VCV during laparoscopic surgery could achieve lower airway pressures and reduce the systemic stress response. Forty ASA I-II patients were randomly selected to receive either the PCV (Group PC, n = 20) or VCV (Group VC, n = 20) during laparoscopic cholecystectomy. Blood sampling was made for baseline arterial blood gases (ABG), cortisol, insulin, and glucose levels. General anesthesia with sevoflurane and fentanyl was employed to all patients. After anesthesia induction and endotracheal intubation, patients in Group PC were given pressure support to form 8 mL/kg tidal volume and patients in Group VC was maintained at 8 mL/kg tidal volume calculated using predicted body weight. All patients were maintained with 5 cmH2O positive-end expiratory pressure (PEEP). Respiratory parameters were recorded before and 30 min after pneumoperitonium. Assessment of ABG and sampling for cortisol, insulin and glucose levels were repeated 30 min after pneumoperitonium and 60 min after extubation. The P-peak levels observed before (18.9 ± 3.8 versus 15 ± 2.2 cmH2O) and during (23.3 ± 3.8 versus 20.1 ± 2.9 cmH2O) pneumoperitoneum in Group VC were significantly higher. Postoperative partial arterial oxygen pressure (PaO2) values are higher (98 ± 12 versus 86 ± 11 mmHg) in Group PC. Arterial carbon dioxide pressure (PaCO2) values (41.8 ± 5.4 versus 36.7 ± 3.5 mmHg) during pneumoperitonium and post-operative mean cortisol and insulin levels were higher in Group VC. When compared to VCV mode, PCV mode may improve compliance during pneumoperitoneum

  12. Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART: Study protocol for a randomized controlled trial

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    2012-08-01

    Full Text Available Abstract Background Acute respiratory distress syndrome (ARDS is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART. Methods/Design ART is a pragmatic, multicenter, randomized (concealed, controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy. We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH2O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet. In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight and targeting plateau pressure ≤30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion If the ART strategy with maximum recruitment and PEEP titration improves

  13. Chest injuries associated with head injury

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    Wilfred Chukwuemeka Mezue

    2012-01-01

    Full Text Available Background: Although there have been significant advances in the management of traumatic brain injury (TBI, associated severe injuries, in particular chest injuries, remain a major challenge. This paper analyses the contribution of chest injuries to the outcome of head injuries in the University of Nigeria Teaching Hospital (UNTH and the Memfys Hospital for Neurosurgery (MHN in Enugu, Nigeria. Materials and Methods: This is a retrospective review of the medical records, operative notes, and radiological findings of all patients admitted for head injury who had associated significant chest injuries in the MHN from 2002 to 2009 and the UNTH between 2007 and 2010. Patients with only head injury and other extracranial injury not affecting the chest were excluded. Patients who were inadequately investigated were also excluded. Results: Nineteen patients from the MHN and 11 patients from the UNTH were analyzed. Ages ranged from 9 to 65 years and the male:female ratio was 3:1. Injuries were most common between 30 and 50 years and road traffic accident accounted for 60%. Barotrauma from ventilation was documented in 2 patients. The commonest types of intrathoracic injuries are pneumothorax and hemothorax. Chest wall injuries are more common but carry less morbidity and mortality. Only 20% of patients presented within 48 hours of injury. Management of the associated chest trauma commenced in the referring hospitals only in 26.4% of the patients. All patients with hemo-pneumothorax had tube thoracostomy as did 96% of patients with pneumothorax. 10% of patients with haemothorax needed thoracotomy. Mortality is 43%, which is higher than for patients with only TBI with comparable Glasgow coma scale. Outcome is influenced by the time to admission and the GCS on admission. Conclusion: Associated chest injuries result in higher mortality from head injuries. This association is more likely in the young and more productive. All patients presenting with head and

  14. Avaliação de alterações timpanométricas em pacientes submetidos à anestesia geral com óxido nitroso Evaluation of tympanometric alterations in patients subject to general anesthesia with nitrous oxide

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    Fernanda Mossumez Fernandes Teixeira

    2005-06-01

    Full Text Available O óxido nitroso é um gás inalatório que pode aumentar a pressão intratimpânica durante o ato anestésico, bem como causar pressão negativa após sua suspensão, principalmente em pacientes com disfunção da tuba auditiva. Estas variações pressóricas podem trazer implicações clínicas, como ruptura de membrana timpânica, desarticulação da cadeia ossicular, hemotímpano, barotrauma, deslocamento de prótese de estapedotomia e lateralização do enxerto nas timpanoplastias, além da entrada de fluido seroso na orelha média durante a fase de pressão negativa. OBJETIVO: Avaliar a influência do óxido nitroso na pressão da orelha média em uma população sem disfunção tubária, realizando timpanometria no pré e pós-operatório. FORMA DE ESTUDO: Coorte transversal. MATERIAL E MÉTODO: Foi realizado um estudo prospectivo com pacientes internados no Hospital Universitário Clementino Fraga Filho - UFRJ, submetidos à anestesia geral com o uso do óxido nitroso a 50%, durante o período de abril a julho de 2003. Avaliou-se ainda se a duração da cirurgia, anestésicos associados, presença de rinite alérgica e desvio de septo nasal poderiam influenciar no aparecimento das alterações da pressão intratimpânica. RESULTADOS: A amostra constituiu-se de 50 pacientes, encontrando-se em quase metade (48% alterações timpanométricas no pós-operatório (curva tipo C, quando comparado às de controle do pré-operatório (curva tipo A. Sexo e idade não interferiram no aparecimento das alterações timpanométricas no pós-operatório, bem como a duração da cirurgia. O tipo de anestésico volátil associado, desvio de septo nasal e rinite alérgica não exerceram influência na pressão da orelha média no pós-operatório. CONCLUSÃO: O óxido nitroso altera a pressão na orelha média tanto na fase de indução quanto na fase de resolução anestésica.Nitrous oxide is an inhaling gas that can increase intratympanic pressure

  15. SPATIALLY-EXPLICIT BAT IMPACT SCREENING TOOL FOR WIND TURBINE SITING

    Energy Technology Data Exchange (ETDEWEB)

    Versar, Inc.; Exponent, Inc.

    2013-10-28

    As the U.S. seeks to increase energy production from renewable energy sources, development of wind power resources continues to grow. One of the most important ecological issues restricting wind energy development, especially the siting of wind turbines, is the potential adverse effect on bats. High levels of bat fatality have been recorded at a number of wind energy facilities, especially in the eastern United States. The U.S. Department of Energy contracted with Versar, Inc., and Exponent to develop a spatially-explicit site screening tool to evaluate the mortality of bats resulting from interactions (collisions or barotrauma) with wind turbines. The resulting Bat Vulnerability Assessment Tool (BVAT) presented in this report integrates spatial information about turbine locations, bat habitat features, and bat behavior as it relates to possible interactions with turbines. A model demonstration was conducted that focuses on two bat species, the eastern red bat (Lasiurus borealis) and the Indiana bat (Myotis sodalis). The eastern red bat is a relatively common tree-roosting species that ranges broadly during migration in the Eastern U.S., whereas the Indiana bat is regional species that migrates between a summer range and cave hibernacula. Moreover, Indiana bats are listed as endangered, and so the impacts to this species are of particular interest. The model demonstration used conditions at the Mountaineer Wind Energy Center (MWEC), which consists of 44 wind turbines arranged in a linear array near Thomas, West Virginia (Tucker County), to illustrate model functions and not to represent actual or potential impacts of the facility. The turbines at MWEC are erected on the ridge of Backbone Mountain with a nacelle height of 70 meters and a collision area of 72 meters (blade height) or 4,071 meters square. The habitat surrounding the turbines is an Appalachian mixed mesophytic forest. Model sensitivity runs showed that bat mortality in the model was most sensitive to

  16. Penguin lungs and air sacs: implications for baroprotection, oxygen stores and buoyancy.

    Science.gov (United States)

    Ponganis, P J; St Leger, J; Scadeng, M

    2015-03-01

    The anatomy and volume of the penguin respiratory system contribute significantly to pulmonary baroprotection, the body O2 store, buoyancy and hence the overall diving physiology of penguins. Therefore, three-dimensional reconstructions from computerized tomographic (CT) scans of live penguins were utilized to measure lung volumes, air sac volumes, tracheobronchial volumes and total body volumes at different inflation pressures in three species with different dive capacities [Adélie (Pygoscelis adeliae), king (Aptenodytes patagonicus) and emperor (A. forsteri) penguins]. Lung volumes scaled to body mass according to published avian allometrics. Air sac volumes at 30 cm H2O (2.94 kPa) inflation pressure, the assumed maximum volume possible prior to deep dives, were two to three times allometric air sac predictions and also two to three times previously determined end-of-dive total air volumes. Although it is unknown whether penguins inhale to such high volumes prior to dives, these values were supported by (a) body density/buoyancy calculations, (b) prior air volume measurements in free-diving ducks and (c) previous suggestions that penguins may exhale air prior to the final portions of deep dives. Based upon air capillary volumes, parabronchial volumes and tracheobronchial volumes estimated from the measured lung/airway volumes and the only available morphometry study of a penguin lung, the presumed maximum air sac volumes resulted in air sac volume to air capillary/parabronchial/tracheobronchial volume ratios that were not large enough to prevent barotrauma to the non-collapsing, rigid air capillaries during the deepest dives of all three species, and during many routine dives of king and emperor penguins. We conclude that volume reduction of airways and lung air spaces, via compression, constriction or blood engorgement, must occur to provide pulmonary baroprotection at depth. It is also possible that relative air capillary and parabronchial volumes are

  17. Clinical efficacy and safety of recruitment maneuver in patients with acute respiratory distress syndrome using low tidal volume ventilation: a multicenter randomized controlled clinical trial

    Institute of Scientific and Technical Information of China (English)

    XI Xiu-ming; JIANG Li; ZHU Bo; the RM group

    2010-01-01

    , 120 minutes after RM. There was no incidence of barotraumas.Conclusions RM was safe and useful for improving oxygenation in patients with ARDS who were ventilated with a low tidal volume, with a beneficial impact on their clinical outcome.

  18. Influência do manuseio do balão autoinflável neonatal sobre o pico de pressão e o volume corrente Peak pressure and tidal volume are affected by how the neonatal self-inflating bag is handled

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    Mariana A. Bassani

    2009-06-01

    88 mL (mean = 39.56 mL; 95%CI 36.86-42.25 for tidal volume. There was no significant influence of the profession on any of the variables (p > 0.05. However, bag handling significantly influenced both peak pressure and tidal volume (p < 0.0001, which were higher when the operator used both hands. CONCLUSION: The results indicate that most professionals delivered excessively high peak pressures and tidal volumes, which could increase the risk of barotrauma and volutrauma, especially when both hands were used to ventilate. On the other hand, a small number of professionals delivered insufficient pressure and volume for adequate lung expansion and ventilation. The delivery of inadequate ventilation was not dependent on profession.

  19. Procedures for restoring vestibular disorders

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    Walther, Leif Erik

    2005-09-01

    round window membrane can, for example, also be caused by an implosive inner ear barotrauma during the decompression phase of diving. Dehiscence of the anterior semicircular canal, a relatively rare disorder, can be treated conservatively (avoiding stimuli which cause dizziness, by non-ablative „resurfacing" or by „plugging" the semicircular canal. A perilymph fistula can cause a Tullio-phenomenon resulting from a traumatic dislocation or hypermobility of the stapes, which can be surgically corrected. Vestibular disorders can also result from otosurgical therapy. When balance disorders persist following stapedectomy it is necessary to carry out a revision operation in order to either exclude a perilymph fistula or shorten the piston. Surgically reducing the size of open mastoid cavities (using for example porous hydroxylapatite or cartilage can result in a reduction of vertiginous symptoms while nursing or during exposure to ambient air. Vestibular disturbances can occur both before and after vestibular nerve surgery (acoustic neuroma. Initially, good vestibular compensation can be expected after surgically removing the acoustic neuroma. An aberrant regeneration of nerve fibers of the vestibulocochlear nerve has been suggested as a cause for secondary worsening. Episodes of vertigo can be caused by an irritation of the vestibular nerve (vascular loop. Neurovascular decompression is generally regarded as the best surgical therapy. In the elderly, vestibular disturbances can severely limit quality of life and are often aggravated by multiple comorbidities. Antivertiginous drugs (e.g. dimenhydrinate in combination with movement training can significantly reduce symptoms. Administering antivertiginous drugs over varying periods of time (e.g. transdermal scopolamine application via patches as well as kinetosis training can be used as both prophylactically and as a therapy for kinetosis. Exposure training should be used as a prophylactic for height vertigo.

  20. Analyses of potential factors affecting survival of juvenile salmonids volitionally passing through turbines at McNary and John Day Dams, Columbia River

    Science.gov (United States)

    Beeman, John; Hansel, Hal; Perry, Russell; Hockersmith, Eric; Sandford, Ben

    2011-01-01

    juvenile steelhead. The negative effect of tag burden in data we examined from yearling Chinook salmon supports the recent findings from laboratory studies of barotrauma effects. A curvilinear (quadratic) effect of turbine unit discharge was weakly supported in data from subyearling Chinook salmon at John Day Dam. The maximum survival from those data was estimated to occur at a discharge of 15.9 thousand cubic feet per second, but the estimate was imprecise (95 percent confidence interval of -1.7-33.7 thousand cubic feet per second). This estimate is within the range of 1 percent of peak turbine operating efficiency (12.0-21.6 thousand cubic feet per second), but is lower than the 17.2 thousand cubic feet per second discharge at peak operating efficiency (at a head of 102 feet near the median in the data we examined). Effects of water temperature were supported in four of the five examined data sets and were strongly supported in all but one. Spill percentage, head, and total discharge received weak or moderate support in some cases. The results are consistent with those of several controlled field experiments of turbine discharge. Studies based on the Hi-Z Turb'N tag (balloon tag) often show small, generally statistically insignificant, differences in survival at different turbine discharge levels. Some studies also show that a quadratic equation can be well fit to the relation of survival and turbine unit discharge. The lack of support for the operational covariates in most of the data sets we examined may be due to the small effect turbine discharge has even in controlled studies, the observational nature of the data we used, and the evaluation method. We assessed support of the data for models of linear and quadratic effects, whereas controlled experiments often statistically compare the point estimates of survival from each operational treatment studied. The results of our analyses suggest tag burden should be minimized or controlled for in analyses of future stu

  1. 神经肌肉阻滞剂对急性呼吸窘迫综合征患者预后影响的荟萃分析%The effect of neuromuscular blocking agents on prognosis of patients with acute respiratory distress syndrome: a meta analysis

    Institute of Scientific and Technical Information of China (English)

    王爱田; 高景利; 李晓岚; 冷玉鑫; 姚智渊; 朱曦

    2013-01-01

    and assessed study quality using standardized instruments.Results Three studies were included in the final analysis,providing a sample of 431 patients.The combined results demonstrated a decrease in 28 days mortality [Peto odds ratio (OR) =0.57,95% confidence interval (95%CI) 0.37-0.88,P=0.01] and lower incidence of barotrauma (OR=0.42,95% CI 0.20-0.91,P=0.003)after NMBA treatment for patients with ARDS as compared with control group.The incidence of acquired neuromyopathy was similar between NMBA group and control group (OR=1.20,95%CI 0.67-2.14,P=0.54).As compared with the control group at 48 hours,there was no statistical difference in ventilator parameters including total positive end expiratory pressure (PEEP,OR=0.09,95%CI-0.50-0.68,P=0.77) and plateau pressure (Pplat,OR=0.62,95%CI -0.32-1.57,P=0.20).There was no heterogeneity (P>0.1,I2<50%).At 120 hours after NMBA treatment,the total PEEP was significantly lower than that of control group (OR =-1.22,95% CI-2.39 to-0.04,P=0.04),and the difference in Pplat showed statistical difference compared with the control group (OR=-2.61,95%CI-4.50 to-0.73,P=0.007).Conclusion Early administration of NMBA for ARDS patients results in a significant reduction in 28 days mortality,and it improves outcome.

  2. Application of bilevel positive airway pressure in treatment of respiratory distress syndrome in preterm infants%双水平持续正压通气在早产儿呼吸窘迫综合征治疗中的应用

    Institute of Scientific and Technical Information of China (English)

    赵小朋; 宋燕燕; 张炼; 陈艳艳; 周媛莉; 张庭艳

    2015-01-01

    . Among them,the preterm infants before January 2013 were selected as control group who were treated with InSurE and nasal continuous positive airway pressure (nCPAP).After January 2013, 60 preterm infants were treated with BiPAP,as BiPAP group.The rates of InSurE failure,the need for mechanical ventilation (MV)on the 7th day after InSurE failure, total non-invasive ventilation time, total mechanical ventilation time, atmospheric oxygen therapy time and incidence of clinical complications were compared between two groups.Results ① There were no significant differences in the clinical data of the preterm infants between two groups, such as gender and age.② Although there was no significant difference in the failure rate of InSurE,but the rate of repeated mechanical ventilation during 1 week in BiPAP group was lower than that in control group (P <0.01).③ The Rank sum test result showed that the total time of non invasive ventilation in BiPAP group was longer than that in control group (P <0.01).The total time of invasive mechanical ventilation and oxygen therapy in BiPAP group was lower than that in control group (P < 0.05).④ The incidence of retinopathy of prematurity (ROP)and bronchopulmonary dysplasia (BPD)in BiPAP group was lower than that in control group.Conclusion BiPAP can significantly reduce the use of invasive mechanical ventilation after the failure of InSurE,thereby decreases the oxygen toxicity and barotrauma hazards.

  3. 跨肺压监测设定呼吸机参数对腹腔高压模型猪血流动力学及氧代谢的作用%Effect of mechanical ventilation guided by transpulmonary pressure on hemodynamics and oxygen metabolism of porcine model of intra-abdominal hypertension

    Institute of Scientific and Technical Information of China (English)

    倪海滨; 李维勤; 柯路; 童智慧; 聂垚; 李宁; 黎介寿

    2011-01-01

    Objective To assess the effect of mechanical ventilation (MV) guided by transpulmonary pressure (Ptp) on hemodynamics and oxygen metabolism of porcine model of intra-abdominal hypertension (IAH). Methods All 6 pigs were anesthetized and received MV. Volume-assist control was set: tidal volume (VT) was 10 ml/kg, respiratory rate (RR) was 16 bpm, inhaled oxygen concentration (FiO2) was 0. 40 and positive end-expiratory pressure (PEEP) was set at 5 cm H2O (1 cm H2O=0. 098 kPa). Following baseline observations, high intra-abdominal pressure (IAP) with intraperitoneal nitrogen inflation was induced in all 6 pigs. The IAP was increased to 25 mm Hg (1 mm Hg=0. 133 kPa). Two hours later, PEEP was adjusted to such a level that Ptp during end-expiratory occlusion remained at a level above 0 cm H2O for 2 hours by measuring esophageal pressure, and with the rest parameters of breathing machine remaining constant. During the experimental period, hemodynamic parameters including heart rate (HR), mean arterial pressure (MAP), cardiac output index (CI), central venous pressure (CVP), pulmonary arterial wedge pressure (PAWP), and respiratory mechanics index of peak airway pressure (Ppeak), plateau pressure (Pplat), esophageal pressure (Pes) and static compliance (Cst) were continuously recorded with the aid of Swan-Ganz catheter and electrocardiogram. Oxygen partial pressure of arterial blood (PaO2) and carbon dioxide partial pressure of arterial blood (PaCO2) were measured by blood-gas analysis. Systemic oxygen delivery (DO2)and systemic oxygen consumption(VO2)were calculated according to blood-gas analysis of arterial and central venous blood. Results No porcine model showed barotrauma and death. Compared with baseline, at 1 hour and 2 hours after induction of IAH in the animals, HR(bpm) increased significantly (134.3±5.8, 127.3±3.3 vs. 117. 7±1.5). MAP(mm Hg), CVP (mm Hg) and PAWP (mm Hg) became higher (MAP:120.7±3.8, 117.3±4.8vs. 100.4±6.6;CVP: 7. 3±0. 3, 7.6±0.9vs. 5