Recompression Chamber Research Articles

Inner ear decompression sickness after a routine dive and recompression chamber drill

ABSTRACT Parsons D, Utz E, Kidd G, Virgilio G. Inner ear decompression sickness after a routine dive and recompression chamber drill. Undersea Hyperb Med. 2024 Second Quarter; 51(2):129-135. Inner ear decompression sickness (IEDCS) is an uncommon diving-related injury affecting the vestibulocochlear system, with symptoms typically including vertigo, tinnitus, and hearing loss, either in isolation or combination. Classically associated with deep, mixed-gas diving, more recent case series have shown that IEDCS is indeed possible after seemingly innocuous recreational dives, and there has been one previous report of IEDCS following routine hyperbaric chamber operations. The presence of right-to-left shunt (RLS), dehydration, and increases in intrathoracic pressure have been identified as risk factors for IEDCS, and previous studies have shown a predominance of vestibular rather than cochlear symptoms, with a preference for lateralization to the right side. Most importantly, rapid identification and initiation of recompression treatment are critical to preventing long-term or permanent inner ear deficits. This case of a U.S. Navy (USN) diver with previously unidentified RLS reemphasizes the potential for IEDCS following uncomplicated diving and recompression chamber operations – only the second reported instance of the latter.

The Influence ofAdvanced Hyperbaric Medical Training onArterial Gas Embolism Treatment.

3d Reconnaissance Battalion, a forward-deployed Marine Corps unit in Okinawa, Japan, frequently performs diving operations. Often throughout the year, several reconnaissance teams are diving simultaneously in different locations for training. We present a case of an otherwise healthy 30-year-old-male Reconnaissance Marine who surfaced from a dive with abnormal symptoms and received prompt care from exercise participants who were nonmedical personnel. Studies have demonstrated improved morbidity outcomes in decompression illness patients with shorter times to hyperbaric treatment following the onset of symptoms. High-risk military exercises with diving components have a mandatory safety structure that includes recompression chamber support. All United States Marine Corps Reconnaissance, Marine Corps Special Operations Command, and U.S. Navy dive operations are required to have at least one diving supervisor. To expand the diving capabilities of the unit, Marines are encouraged to attend training and qualify as diving supervisors. This case study demonstrates the efficacy and importance of training Recon Marines to recognize decompression illness as diving supervisors.

Cardiac arrest in diving: The key to success

This case report describes the successful management of an out-of-hospital arrest in a diver following a suspected arterial gas embolism (AGE). It illustrates both the inherent risks of diving and the importance of prompt and effective implementation of the “chain of survival” from bystanders. Rapid on-scene responses from paramedics and helicopter emergency medical services facilitated prompt evacuation to a Category 1 (multiplace) recompression chamber (RCC) where specialists in cardiology and hyperbaric medicine were available. Alternative causes of cardiac arrest were considered, with a presumed AGE successfully treated with multiple rounds of hyperbaric oxygen therapy. The key factors which led to this successful outcome are discussed, including early recognition and call for help, competent cardiopulmonary resuscitation, and direct evacuation to a Category 1 RCC, with additional consideration of the diagnosis leading to cardiac arrest. The case clearly illustrates the need for all those involved in diving regularly to be competent and confident in performing basic life support, as well as the awareness of the emergency services of the need for diving casualties to be treated at appropriate hyperbaric facilities. Were it not for the simple, prompt and effective treatment this diver received, both on scene and in hospital, it is highly unlikely that such a positive outcome would have been achieved.

Inner ear decompression sickness after a routine dive and recompression chamber drill: A case report

Inner ear decompression sickness (IEDCS) is an uncommon diving-related injury affecting the vestibulocochlear system, with symptoms typically including vertigo, tinnitus and hearing loss, either in isolation or in combination. Classically associated with deep, mixed-gas diving, more recent case series have shown that IEDCS is indeed possible after seemingly innocuous recreational dives, and there has been one previous report of IEDCS following routine hyperbaric chamber operations. The presence of right-to-left shunt (RLS), dehydration and increases in intrathoracic pressure have been identified as risk factors for IEDCS, and previous studies have shown a predominance of vestibular rather than cochlear symptoms, with a preference for lateralization to the right side. Most importantly, rapid identification and initiation of recompression treatment are critical to preventing long-term or permanent inner ear deficits. This case of a U.S. Navy (USN) diver with previously unidentified RLS reemphasizes the potential for IEDCS following uncomplicated diving and recompression chamber operations – only the second reported instance of the latter.

Diagnostic, facteurs de risque et prévention des pathologies de la haute altitude

AbstractExposure to high altitude requires gradual acclimatization. When it is not respected, specific pathologies can arise, the minor form of which is acute mountain sickness (headaches, digestive disorders, fatigue, insomnia) and the complicated forms are high altitude pulmonary and cerebral edema which are life-threatening emergencies. Preventive treatment is essentially based on a gradual ascent (400 m rule) and acetazolamide. Curative treatment involves rest, analgesics for minor forms, reoxygenation (descent, oxygen, recompression chamber) and corticosteroids for severe forms. To treat pulmonary edema, additional calcium channel blockers or PDE5 inhibitors are given to lower pulmonary arterial pressure. A mountain medicine consultation with a hypoxia exercise test makes it possible to detect subjects at risk of developing serious forms and to offer advice adapted to each individual.

Arrhythmogenicity of scuba diving Holter monitoring in a hyperbaric environment

Introduction: About 26% of diving-related fatalities are caused by cardiac disease, part of which might be associated with fatal arrhythmias. This raises the question as to whether fatal arrhythmias are being provoked by hyperbaric conditions themselves or if exercise or stress provokes the fatal arrhythmias in cases of underlying (ischemic) cardiac disease. Objective: To measure the influence of hyperbaric conditions (50 msw) on cardiac conduction and arrhythmias in professional divers by means of ECG. Methods: This is a prospective study on military divers in a hyperbaric chamber with continuous ECG monitoring using Holter registrations. Supraventricular and ventricular ectopy was registered during hyperbaric conditions. RR, PR, QRS, QT and QTc intervals were calculated at 50 msw and compared with ECGs at rest. Results: Included were 17 male military divers who made 20 dives. A total of 10 PVCs, 45 PACs, four atrial runs and four atrial pairs were seen. Significant prolongation of the PR interval was seen and a decrease of in QRS duration at 50 msw. There was no significant change in the RR, QT and QTc intervals. Conclusions: In these divers, no clinically relevant arrhythmias were observed during wet dives in a recompression chamber at 50 msw. We observed a small prolongation of PR interval that is probably not clinically relevant in divers without any known conduction disorders.

In-water recompression.

Divers suspected of suffering decompression illness (DCI) in locations remote from a recompression chamber are sometimes treated with in-water recompression (IWR). There are no data that establish the benefits of IWR compared to conventional first aid with surface oxygen and transport to the nearest chamber. However, the theoretical benefit of IWR is that it can be initiated with a very short delay to recompression after onset of manifestations of DCI. Retrospective analyses of the effect on outcome of increasing delay generally do not capture this very short delay achievable with IWR. However, in military training and experimental diving, delay to recompression is typically less than two hours and more than 90% of cases have complete resolution of manifestations during the first treatment, often within minutes of recompression. A major risk of IWR is that of an oxygen convulsion resulting in drowning. As a result, typical IWR oxygen-breathing protocols use shallower maximum depths (9 metres' sea water (msw), 191 kPa) and are shorter (1-3 hours) than standard recompression protocols for the initial treatment of DCI (e.g., US Navy Treatment Tables 5 and 6). There has been no experimentation with initial treatment of DCI at pressures less than 285 kPa since the original development of these treatment tables, when no differences in outcomes were seen between maximum pressures of 203 kPa (10 msw) and 285 kPa (18 msw) or deeper. These data and case series suggest that recompression treatment comprising pressures and durations similar to IWR protocols can be effective. The risk of IWR is not justified for treatment of mild symptoms likely to resolve spontaneously or for divers so functionally compromised that they would not be safe in the water. However, IWR conducted by properly trained and equipped divers may be justified for manifestations that are life or limb threatening where timely recompression is unavailable.

Medical Management and Risk Reduction of the Cardiovascular Effects of Underwater Diving.

Undersea diving is a sport and commercial industry. Knowledge of potential problems began with Caisson disease or "the bends", first identified with compressed air in the construction of tunnels under rivers in the 19th century. Subsequently, there was the commercially used old-fashioned diving helmet attached to a suit, with compressed air pumped down from the surface. Breathhold diving, with no supplementary source of air or other breathing mixture, is also a sport as well as a commercial fishing tool in some parts of the world. There has been an evolution to self-contained underwater breathing apparatus (SCUBA) diving with major involvement as a recreational sport but also of major commercial importance. Knowledge of the physiology and cardiovascular plus other medical problems associated with the various forms of diving have evolved extensively. The major medical catastrophes of SCUBA diving are air embolism and decompression sickness (DCS). Understanding of the essential referral to a hyperbaric recompression chamber for these problems is critical, as well as immediate measures until that recompression is achieved. These include the administration of 100% oxygen and rehydration with intravenous normal saline. Undersea diving continues to expand, especially as a sport, and a basic understanding of the associated preventive and emergency medicine will decrease complications and save lives.

A historical review of the U.S. Navy’s busiest recompression chamber in the Pacific theater with a current perspective on caring for civilian divers within its area of responsibility: short communication

On the island Nation of Guam, the United States Department of Defense has stationed military personnel from every service branch. Guam is utilized as a strategic waypoint for the U.S. military in the Pacific theater. As the largest service branch in the region, the Navy has placed a few Diving Medical Officers in Guam to collectively manage and treat patients with recompression therapy. Guam is also a popular tourist destination, with multiple recreational diving companies certifying individuals who are looking to take advantage of the beautiful warm water and exotic marine life. Unfortunately, with an increase in training and certifying inexperienced divers, came an increase in the operational tempo of the U.S. Navy's recompression chamber on Guam. The recompression chamber on Naval Base Guam (NBG) has been treating patients since 1971. With the only multiplace chamber in the Mariana Islands, Diving Medical Officers, with the accompanying chamber staff, treat military personnel, active-duty sponsored patients and civilian patients. Treating civilian patients by military providers through military treatment facilities presents multiple issues that must be addressed in an effort to provide efficient quality medical care. This article reviews the records, documents, and activity of the NBG chamber over the last four decades. Through the obtained data the information provides projected financial reimbursement from civilian patients. The article also sheds light on areas of needed improvement with regard to data collection, third-party financial collection efforts and the necessity of an inclusive electronic health record (EHR) for military and civilian patients.

Decompressing recompression chamber attendants during Australian submarine rescue operations.

Inside chamber attendants rescuing survivors from a pressurised, distressed submarine may themselves accumulate a decompression obligation which may exceed the limits of Defense and Civil Institute of Environmental Medicine tables presently used by the Royal Australian Navy. This study assessed the probability of decompression sickness (PDCS) for medical attendants supervising survivors undergoing oxygen-accelerated saturation decompression according to the National Oceanic and Atmospheric Administration (NOAA) 17.11 table. Estimated probability of decompression sickness (PDCS), the units pulmonary oxygen toxicity dose (UPTD) and the volume of oxygen required were calculated for attendants breathing air during the NOAA table compared with the introduction of various periods of oxygen breathing. The PDCS in medical attendants breathing air whilst supervising survivors receiving NOAA decompression is up to 4.5%. For the longest predicted profile (830 minutes at 253 kPa) oxygen breathing at 30, 60 and 90 minutes at 132 kPa partial pressure of oxygen reduced the air-breathing-associated PDCS to less than 3.1 %, 2.1% and 1.4% respectively. The probability of at least one incident of DCS among attendants, with consequent strain on resources, is high if attendants breathe air throughout their exposure. The introduction of 90 minutes of oxygen breathing greatly reduces the probability of this interruption to rescue operations.

A Short Report on Decompression Sickness Incidents in Andaman and Nicobar Islands

Objectives: Due to presence of extensively fascinating coral reef ecosystem in the continental shelf of Andaman and Nicobar Islands, people from all over the world visit these islands of India to indulge in recreational diving. An increased participation figure has also elevated the number of divers at risk for Decompression Sickness (DCS). Despite this, no scientific data are available on DCS incidents from India. Present study is aimed to evaluate the DCS incidents reported in these islands, treatment provided, and the outcome of the treatment. An attempt has also been made to calculate the approximate frequency of DCS in comparison to the participation figure. Methods: Study design is retrospective data analyses of a recompression chamber. Naval Diving Unit Port Blair has the only active decompression chamber available in the islands, and Govind Ballabh Pant Hospital Port Blair was used to collect information on DCS incidents that occurred during the mentioned period. Due to lack of authenticated generalized documents of divers’ health history and dive logs, the scanty information was gathered from the dive centres on the basis of personal interviews/communications among the SCUBA diving instructors. Results: A total of nine cases were reported during the span of last four and half years, and thus approximate frequency of DCS in Andamans was 0.2/10000 divers year. All of the patients recovered completely after receiving the Hyperbaric Oxygen Therapy (HBOT), with no residual symptoms. Conclusions: Incident rate of DCS in Andamans is lower than that in many other parts of the world; possible reason could be under-reporting of less severe DCS cases. During the study period, the number of DCS type II incidents presented for the treatment was higher than that of DCS type I incidents. HBOT proved a complete success in treating DCS cases in the island.

Dysbarism

Dysbarism is defined as any medical condition that arises as a result of changes in ambient pressure. This review describes dysbarism with a focus on the undersea environment. Conditions discussed in this review include middle and inner ear barotrauma, pulmonary barotrauma, immersion pulmonary edema, decompression illness, and gas toxicities. For each, assessment and stabilization, treatment and disposition, and outcomes are presented. Figures show the AQUARIUS habitat for saturation diving; the anatomy of the external, middle, and inner ear; the Teed classification; the paranasal sinuses; and an example of a recompression chamber. Tables list the types of diving, gas laws relevant to diving, units of underwater pressure, compositions of typical breathing gas mixtures, decompression illness risk factors, symptoms of decompression illness (in order of frequency), signs and symptoms of decompression illness based on body system, maximum recommended depth to reduce the risk of central nervous system oxygen toxicity for various breathing gas mixtures, and progression of nitrogen narcosis symptoms with increasing depth. This review contains 5 highly rendered figures, 9 tables, and 120 references.

Does Hyperbaric Oxygen Therapy Have a Role in Diabetic Autonomic Neuropathy ?

Objectives: To determine if hyperbaric oxygen therapy could benefit patients with diabetic autonomic neuropathy treated at our hospital. Methods: Thirty-one consecutive patients, who were treated at Princess Haya Hospital and Prince Hahim Bin Abdullah II hospital from January 2012 to April 2014, were included. Four tests of autonomic function were carried out on all patients before and after treatment in the hyperbaric recompression chamber. Data analyzed using Statistical Package for the Social Sciences version 17 and stata version 10. Results: Twenty male and eleven female patients were included, with a mean age of 53.6 years. About 84% had Type II diabetes. Seventy-one percent of patients were found to have greater than or equal to three abnormal tests prior to treatment, and the risk of autonomic neuropathy was found to be independent of patients' sex, age, type or duration of diabetes. A statistically significant improvement was found in all tests after hyperbaric oxygen therapy. The improvement in parasympathetic function was found to be more likely affected by the number of sessions than sympathetic function (P value 0.001 and 0.07, respectively) Conclusion: Hyperbaric oxygen therapy is a promising technology in the treatment of diabetic autonomic neuropathy. Further research which includes a control group is needed.

Unusual occurrence of diving accidents : Case reports from andaman & nicobar islands

Introduction: Andaman and Nicobar islands due to their unique location offer several exclusive diving sites and form a hub of recreational SCUBA diving and commercial diving. This in turn increases the possibility of diving accidents in these areas. Seven cases with a wide spectrum of presentations and rare symptoms has been compiled in this article. Observations : Six cases of “Decompression Sickness” which is rare type of diving accidents in the recent times, were reported with rare and varied symptoms. Out of six cases of DCS, four were type 2 with varied presentations due to neurological, cerebellar, pulmonary etc. involvement and only one case was type 1 with skin involvement. Joint manifestation which is the common form of DCS (popularly known as “Bends”) was not reported. A thorough history, good clinical examinations, advice from Marine Medicine Specialists and prompt administration of Recompression therapy were the key factors for successful recovery of such cases. Conclusions: Management of Decompression Sickness (DCS) can be extremely challenging both in the pre-hospital and hospital care setup. This could be convoluted further by lack of hyperbaric chamber and trained staff. Availability of a Recompression chamber (RCC) has been a boon in remote areas where such cases are common.

Decompression sickness in naval divers

Introduction: Diving is a n operational commitment of navy. Diving operations are conducted with I without the presence of a MM spl. Study of MM done along with phases of attachments at different diving operational units as practical orientation. Classes of Divers: (a) Ship Diver (SD). Trained to dive up to 35 MSW (b) Clearance Diver (CD): They are trained to dive up to 55 MSW. (c) CD (DD): They are Deep divers, also trained in saturation diving using Helium Oxygen mixture, (d) Chariot Diver: They are combat divers of the Navy. (e)Air crew diver: Specially trained SD & CD. (f) Combat Diver: from Army. Diving Establishments: Diving School - shore estt, kochi. INS Nireekshak - floating platform. INS Satavahana - submarine training estt - shore estt, vizag. INS Abhimanyu - chariot diving with pure Oxygen breather for clandestine operations. CCDH! - one per command, CDU at A & N. INS Matanga, INS Gaj - floating platforms. Recompression Chamber Complex, INHS Asvini Decompression Sickness: Due to metabolically inert gases and due to fast ascent rate. It is never with pure oxygen diving. Never occur while at bottom. As per grading, Type I - not serious type, generally known as bends and Type II - serious type Treatment: Treatment for DCS is followed as per guidelines promulgated in INBR 2806. Mainstay of treatment remains with Oxygen Table 61 & 62 of INBR 2806 which is same as RNBR 2806 as table 5&60fUS navy D i v i n g Manual. Incidences: Incidences of DCS are found at Diving School and Nireekshak. At ETS other diving related injuries like Mask injury, hypoxia, CAGE are documented. At CCDTk no DCS documented in last five years. Conclusion: DCS in Navy is rather very less due to stringent training, fitness of divers and proper follow of procedures.

Effects of FLIRT on Bubble Growth in Man

Recompression during decompression has been suggested to possibly reduce the risk of decompression sickness (DCS). The main objective of the current study was to investigate the effects of FLIRT (First Line Intermittent Recompression Technique) on bubble detection in man. 29 divers underwent 2 simulated dives in a dry recompression chamber to a depth of 40 msw (500 kPa ambient pressure) in random order. A Buehlmann-based decompression profile served as control and was compared to an experimental profile with intermittent recompression during decompression (FLIRT). Circulating bubbles in the right ventricular outflow tract (RVOT) were monitored by Doppler ultrasound and quantified using the Spencer scoring algorithm. Heat shock protein 70 (HSP70), thrombocytes, D-Dimers and serum osmolarity were analyzed before and 120 min after the dive. Both dive profiles elicited bubbles in most subjects (range Spencer 0-4). However, no statistically significant difference was found in bubble scores between the control and the experimental dive procedure. There was no significant change in either HSP70, thrombocytes, and D-Dimers. None of the divers had clinical signs or symptoms suggestive of DCS. We conclude that FLIRT did not significantly alter the number of microbubbles and thus may not be considered superior to classical decompression in regards of preventing DCS.

An introduction to diving medicine and decompression sickness

Diving is a perilous activity. Long exposure to the subaquatic environment results in many troubles to divers. In Korea, the number of divers, especially recreational ones, is soaring up and the incidence of diving related accidents and illnesses is also increasing rapidly. Consequently, diving medicine which approaches underwater medical problems is getting more important to doctors as well as divers. Decompression sickness (DCS) is one of the most typical diseases in diving medicine, and divers who breathe compressed air or mixed gas always have a risk of suffering from it. DCS is caused by bubbles from dissolved inert gas as a result of decompression. The diagnosis of DCS is based completely on clinical manifestations, but it is not easy to make a correct diagnosis due to various symptoms. In general, DCS needs prompt recompression chamber treatment with trained medical and paramedical staff, but few doctors are trained to handle diving related diseases like DCS and most people in Korea are not aware of diving medicine. Additionally, lack of recompression facilities hinders DCS patients from taking treatment timely. To deal with these problems, Korean government as well as doctors needs to show deep concern at this field.

Antarctic Medicine—The Challenges of Being a Doctor in an Isolated and Confined Environment

Rothera research station is a British Antarctic Survey (BAS) base on the Antarctic Peninsula that is operational year round. During the 8-month winter the 20 people living there are physically isolated from any other humans. I was the resident doctor during the 2005 season. I did not leave Antarctica for 17 months of my employment with the British Antarctic Survey Medical Unit (BASMU), and during the winter period I was the sole medical practitioner on station. My medical work load was light in comparison to any other job I have done. All personnel deployed to a UK Antarctic base were fit and well, and the wintering team in particular had been screened for any significant physical and mental illness. On average during the winter period I would perform 40 consultations per month. Because I was only serving a population of 20, the relatively large number of consultations reflected the harsh environment in which we lived and worked. The perceived major health risks of BAS Antarctic employment were the operational tasks of year round SCUBA diving and summer light aircraft movements and environmental cold injuries. Predeparture training and on-site equipment (eg, a recompression chamber) equipped me to deal with these issues. However, most of my work load was composed of minor injuries sustained during work or leisure pursuits in the difficult environment, psychological issues, dental work, gynecology, and genitourinary medicine. During the summer months there were 2 doctors, one who had just arrived and one who had finished a winter season and would return home at the end of summer. One doctor was always on base, as diving and aircraft operations continue throughout the 24-hour daylight. In winter the solo doctor took part, as all base members did, in 2 winter training trips, each a week long, which made them inaccessible to base other than through a nightly prearranged radio call. During this time remote assistance and advice was provided to the station by BASMU based in Plymouth, UK. This group of specialist consultants also provided advice and support for the doctor throughout the term of duty. There are many aspects of the season I spent in Rothera that I will continue to reflect on for some time. The enclosed environment created an amplified feedback on many of my actions and forced a range of emotions. Although few of the medico-social issues are unique to Rothera, I had never before been in a position where every action or word on my part, either in a clinical situation or socially, had the potential to significantly change my relationship with the other members of my group (particularly in winter) and alter my ability to serve that group as a doctor. I would like to discuss specifically the topics of medical confidentiality, treatment styles, 24-hour on-call duties, and personal relationships.

Recompression Treatment of Red Sea Diving Accidents

The growing popularity of diving sport has resulted in more diving accidents. Our objective was to characterize Red Sea divers requiring recompression treatment in Eilat, to recognize 23-year trends of diving accidents, and to facilitate appropriate administrative and treatment tools for diving accident in this area. Retrospective, uncontrolled study. Recompression unit at a Red Sea medical center. Charts of all divers treated at Eilat's recompression chamber from October 1976 to December 1999 were reviewed. Recompression treatment. During this period, annual crude numbers increased 5-fold, and a total of 453 patients were treated. Of them, 68% were Israelis and 32% tourists; 76% were males and 23% females; and 21.6% were diving buddies of injured divers (omitted decompression). The mean diving depth causing the accident was 30.2 +/- 13.1 m, and >50% of accidents occurred between 11 and 30 m. Over 42% suffered from decompression sickness (DCS) type 2, 26% from DCS type 1, and 7% from barotraumas. Women, unlike men, presented predominantly DCS type 2 (54% vs. 39%; P = 0.01) and sustained DCS at shallower waters (25.2 +/- 9.1 m) than men (31.8 +/- 13.8 m; P < 0.0001). Primarily, treatment followed recompression in alternating cycles of oxygen and air as stipulated in US Navy Tables 5 (18.1%) and 6 (37.5%). The 48-hour case fatality rate was 0.09%. This large survey of open sea diving accidents accentuated the need for a national registry of diving accidents and a national database of diving activities.

Natural history of severe decompression sickness after rapid ascent from air saturation in a porcine model.

We developed a swine model to describe the untreated natural history of severe decompression sickness (DCS) after direct ascent from saturation conditions. In a recompression chamber, neutered male Yorkshire swine were pressurized to a predetermined depth from 50-150 feet of seawater [fsw; 2.52-5.55 atmospheres absolute (ATA)]. After 22 h, they returned to the surface (1 ATA) at 30 fsw/min (0.91 ATA/min) without decompression stops and were observed. Depth was the primary predictor of DCS incidence (R = 0.52, P < 0.0001) and death (R = 0.54, P < 0.0001). Severe DCS, defined as neurological or cardiopulmonary impairment, occurred in 78 of 128 animals, and 42 of 51 animals with cardiopulmonary DCS died within 1 h after surfacing. Within 24 h, 29 of 30 survivors with neurological DCS completely resolved their deficits without intervention. Pretrial Monte Carlo analysis decreased subject requirement without sacrificing power. This model provides a useful platform for investigating the pathophysiology of severe DCS and testing therapeutic interventions. The results raise important questions about present models of human responses to similar decompressive insults.