Review of Human Physiology in the Underwater Environment

Since before centuries, human tries hard to explore underwater and in 1940’s human-introduced an important and revolutionary gear i.e. scuba that allowed human-made long interaction in the underwater world. Since diving using pressure gas under pressure environment, it should be considered to remember gas law (Boyle’s law). The gas law gives a clear understanding of physiological consequences related to diving diseases such as barotrauma or condition in which tissue or organ is damage due to gas pressure. The organ which has direct effect related to compression and expansion of gas were lungs, ear, and sinus. These organs were common and potentially fatigue injury for a diver. In this article we shall review the history of scuba diving, physical stress caused underwater environment, physiology adaptation of lung, ear, and sinus, and diving disease.

SCUBA Diving Fatality by Overweighted Belt: An Autopsy Case / 대한법의학회지

Scuba diving is a popular sports activity, even though it is associated with potential hazards. When a diver enters the water for an underwater expedition, he/she needs a series of diving gear, including a regulator, buoyancy compensator, diving suit, and weight belt, among others. Here, the author encountered a fatal diving accident wherein autopsy showed the evidence of death by drowning. The witness stated that the diver requested more weight to descend into the water, and the diver wore one more weight belt, totalling 26 kg. After a second trial of diving, he did not grab the regulator and disappeared into the water suddenly, and bubbles did not appear at the surface. Based on the witness statement and autopsy findings, the original cause of accident was concluded as an overweighted belt for descent into the water.

06-3Rehabilitation to residual functional disorders in spinal decompression sickness resulting from recreational scuba diving / 日本温泉気候物理医学会雑誌

  Spinal decompression sickness including spinal cord damage is indeed a rare sickness, and in particular, there have been few reports on residual functional disorder. This case was a 39-year-old male who had been a recreational scuba diver for 13 years. While scuba diving overseas, he had suffered from decompression sickness with spinal cord involvement. As a result, imcomplete paraplegia with spasticity, sensory disturbance, neurogenic bladder and bowel disturbance occurred. Inclusive rehabilitation containing physical therapy, was provided to control the spasticity, the pain, and the improvement of the activities of daily living was thereby achieved. However, the changes of the muscle hardness, paresthesia, and hyperalgesia, and the disturbance of position and vibration sense remained. The cause of spinal decompression sickness is not clear, but a venous embolism in the spinal veins has been reported. Further observation is considered necessary.

06-3 Rehabilitation to residual functional disorders in spinal decompression sickness resulting from recreational scuba diving / 日本温泉気候物理医学会雑誌

  Spinal decompression sickness including spinal cord damage is indeed a rare sickness, and in particular, there have been few reports on residual functional disorder. This case was a 39-year-old male who had been a recreational scuba diver for 13 years. While scuba diving overseas, he had suffered from decompression sickness with spinal cord involvement. As a result, imcomplete paraplegia with spasticity, sensory disturbance, neurogenic bladder and bowel disturbance occurred. Inclusive rehabilitation containing physical therapy, was provided to control the spasticity, the pain, and the improvement of the activities of daily living was thereby achieved. However, the changes of the muscle hardness, paresthesia, and hyperalgesia, and the disturbance of position and vibration sense remained. The cause of spinal decompression sickness is not clear, but a venous embolism in the spinal veins has been reported. Further observation is considered necessary.

Technical Approach for the Postmortem Examination of SCUBA Diving Fatality / 대한법의학회지

Recreational diving is an exciting and adventurous sport, but is also potentially hazardous. Despite its inherent hazards, an increasing number of people enjoy SCUBA (self-contained underwater breathing apparatus) diving; the number of diving-related accidents is therefore also likely to increase. Divers might face physical or psychological stresses from the unfamiliar or hostile underwater environment, which can lead to fatal accidents. To investigate deaths related to SCUBA diving, a forensic pathologist should understand the types and mechanisms of injuries and illnesses unique to SCUBA diving. Postmortem examination of diving fatalities is therefore a formidable task for most forensic pathologists because cases are sparse and the process requires an understanding of diving physiology, diving equipment, and the underwater environment. The primary aim of autopsies in SCUBA diving fatalities is to detect evidence of pulmonary barotrauma, intravascular gas, or pre-existing illnesses. Standard autopsy protocol for SCUBA diving-related deaths should include methods to detect intravascular gas and gas accumulation in the tissue or body cavity through plain radiographs or Computerized Tomography (CT) scans. Analysis of the gas components is also helpful for determining the origin of the gas. Here, the author proposes a practical method for performing an autopsy on a person who died while SCUBA diving.

Survey of SCUBA Divers in Korea Focused on Forensic Implications / 대한법의학회지

This study aimed at surveying recreational scuba divers in order to determine demographic characteristics such as diving certification level and diving times, history of medical illnesses or injuries, and incidence of accidents or risks during underwater diving. For this, the authors contacted the managers of 190 diving clubs, which are listed on an online site called "DiveWeb." Responses were obtained from 87 diving clubs, amounting to a total of 154 completed questionnaires. The authors also visited a 4-day-long "Seoul International Sports & Leisure Industry Show" and collected 168 completed questionnaires from certified divers who visited the show. The collected data were analyzed by SPSS for Windows, version 17.0. We found the following results among 314 divers: 261 (83.1%) were male, and 221 (70.4%) were aged 30 to 49 years; 174 divers (55.4%) had over 5 years of diving experience; average body mass index (24.13) was within normal limits; number of non-smokers (175) was greater than that of smokers (139); 110 (35.0%) divers reported past or present diseases (allergic rhinitis being the most common) or injury history. Risky situations that were encountered by the divers included currents, underwater environment, buddy system complications, and air depletion during diving. Underwater diving is a potentially hazardous activity, but at present, medical examinations or fitness tests are not a prerequisite for certified divers in Korea. To secure the safety of underwater divers, we need to establish policies for medical checkups and fitness tests before the divers begin training or attain certification.

Alveolar Siderophages : A Precipitating Factor in a Fatal Scuba Diving Accident?: An Autopsy Case / 대한법의학회지

The author report the case of a 40-year-old male leisure scuba diver (height, 176 cm; weight, 73 kg) who died from asphyxiation by aspiration of gastric content, allegedly triggered by pulmonary hemosiderosis and/or full stomach. On the first dive of the day, the deceased complained of difficulty in descent and tried to descend several times but finally gave up and separated from his companions. After several minutes of separation, he was found dead, face down position on the sea surface, by the captain of the boat carrying the diving party. On autopsy, the lungs showed foreign bodies from stomach, intra-alveolar hemorrhage, and siderophages in the alveolar sac. A small amount of air bubbles was noted in the mesenteric vein, iliac artery, right ventricle and pulmonary artery. The cause of death was asphyxiation by aspiration of gastric content and pulmonary hemosiderosis, which probably provoked the event. Alveolar hemosiderosis may be a causal factor in fatal scuba diving accident.

The Changes of Intraocular Pressure, Optic Nerve and Visual Field in SCUBA Diving

PURPOSE: To examine how SCUBA diving activities in high-pressure underwater environment affect their intraocular pressure (IOP), visual field (VF), retinal nerve fiber layer (RNFL), and the shape of optic disc. METHODS: We performed visual acuity and refractory test, IOP test, VF test, RNFL photography, optical coherent tomography, and 3D optic disc photography for a group of 32 people and a control group of 32 non-divers, and analyzed the differences between the two groups. For the diver group, we conducted a questionnaire survey on the patterns of diving and diving experience, and analyzed their correlation with results of test. RESULTS: Compared to the Control, the diver group showed significant difference in the mean IOP (diver group: 15.71 +/- 2.54 mmHg, control group: 14.23 +/-2.15 mmHg, p = 0.019), and abnormal visual field (diver group: 7 eyes (11.3%), control group: 0 eye (0%), p = 0.006). 85.7% of abnormal visual field belonged to early defect. The diver group did not showed significant difference in the shape of optic disc (p = 0.546), but the optic nerve atrophy in shape of optic disc test field (diver group: 8 eyes (12.9%), control group: 2 eyes (3.1%), p = 0.042) was significantly different. CONCLUSIONS: Divers who did SCUBA diving activities need to have a glaucoma test regularly. Additional research and large cross or longitudinal study are needed to evaluate causes that scuba diving activities affect.

Checklist for Forensic Investigation on Fatal SCUBA Diving Accidents / 대한법의학회지

SCUBA diving is becoming one of popular sport around the world even though it has serious accident potentials. The most common cause of death in underwater diving fatality is drowning, but in many cases it could be just a terminal event. The eventual target of forensic investigation in underwater diving accidents is to examine the underlying cause of death or accident, and therefore forensic pathologists should get an information about diving equipments which were used by the victim and about environmental factors. The author think a uniformed check list of underwater diving accidents should be available for postmortem investigation, and here propose it.

The Brachyura and Anomura fauna (Decapoda; Crustacea) in the Arvoredo Marine Biological Reserve on the southern brazilian coast

Eight species of Brachyura and two species of Anomura were registered for the first time on the Santa Catarina coast, in the waters around the Arvoredo Marine Biological Reserve. The animals were collected by scuba divers, between 3 and 22 meters depth, from September 2001 to February 2003. A total of 31 decapod species were collected, and most of the new occurrences had already been registered in the adjacent northern waters.

Oito espécies de Brachyura e duas espécies de Anomura foram registradas pela primeira vez na costa de Santa Catarina, em águas no entorno da Reserva Biológica Marinha do Arvoredo. Os animais foram coletados por meio de mergulho autônomo, entre 3 e 22 metros de profundidade, de setembro 2001 a fevereiro de 2003. Um total de 31 espécies de Decapoda foram coletadas e a maioria das novas ocorrências já haviam sido registradas em águas adjacentes ao norte da Reserva.

Forensic Review of Underwater Diving-Related Death / 대한법의학회지

The popularity of SCUBA diving as aquatic sports is increasing in trend and therefore the risk of diving-related accidents or death is also increased. In underwater environment, with its rapidly changing ambient pressures, human body is subjected to pathophysiologic challenges. The common forms of medical problem with diving are barotrauma, decompression sickness and nitrogen narcosis, and the most common cause of diving-related death is drowning. However, the determination of the cause of death associated with diving should not be derived from the autopsy alone but must result from interpretation of data including a detailed history of the events prior to death, information about accident locus, diving suits, breathing apparatus and their accessories, and complete autopsy including toxicology and histological examination. And to explain the mechanism of death, the forensic pathologists should understand the diving physiology, law of gas physics and other diving hazards, and also be approached by the team effort involved by professional diver. Through the review of cases of SCUBA diving-related death and the literature, the author discuss the investigative approach to diving accidents and complete autopsy procedure with toxicological screen.

Barotrauma of the Middle Ear in Guinea Pigs after Simulated Diving / 대한이비인후과학회지

To confirm the possibility of middle ear barotrauma in Guinea Pigs even to safe, recomm-endable diving profiles to sports SCUBA divers and to study operating microscopic findings and progress of middle ear barotrauma, 16 Guinea Pigs were exposed to hyperbaric chamber for simulated diving. Simulated diving profiles were 20 meter sea water of maximum depth, 18 meter per minute of ascent, descent rates, 20 minutes of bottom time, 60 minutes of surface interval time and 2 repetitive dives in a day for 2 consecutive days. Then, tympanic membrane, middle ear and round membrane window were examined by operating microscope on 1 day, 7 days after simulated diving respectively. The experimental results showed that 26 of 32 ears(81.2%) disclosed findings of barotrauma in total, 23 ears(71.9%) in tympanic membrane, 25(78.1%) in middle ear, 7 ears(21.9%) in round window membrane respectively. The main operating microscopic findings of barotrauma were hyperemia of tympanic membrane in 23 ears(71.9%), hyperemia in 25 ears(78.1%), bleeding in 22 ears(68.8%) of middle ear, followed by bleeding, perforation of tympanic membrane, edema, effusion in middle ear, bleeding and rupture of round window membrane in order. Hyperemia of tympanic membrane and bleeding of middle ear in day 7 group showed significantly lower rate of barotrauma than those of day 1 group, that suggest spontaneous improvement in mild case of experimental middle ear barotrauma.