Self-reported vitality and health status are higher in Dutch submariners than in the general population.

Introduction: Living aboard submarines has a potential negative effect on health. Although studies have evaluated specific health hazards and short-term outcomes, long-term health effects have not been investigated in this population. Methods: Veteran submariners were contacted through the veterans' society and administered a World Health Organisation validated questionnaire (SF-36) assessing their physical, emotional, and social functioning. Scores were compared with those of the general (reference) population and scores in veteran submariners were differentiated by rank, time at sea and time in service. Statistical analyses were performed using the Wilcoxon signed rank and Kruskal-Wallis tests. Results: Of the 1,025 submariners approached in December 2019, 742 (72.4%) completed and returned the questionnaire before July 2020. All 742 were men, of median age 68 (interquartile range [IQR] 59-76) years (range 34-99 years). Of these subjects, 10.3% were current smokers, 64.4% were former smokers and 23.7% had never smoked. Submariners scored significantly better (P < 0.001) than the general population on all eight domains of the SF-36. Except for 'pain' and 'change in health status over the last year', scores for all domains decreased with age. Scores were not significantly affected by smoking status, rank, service, and time at sea. Conclusions: Dutch veteran submariners have better self-reported vitality and health status than the general Dutch population. Rank, service, and time at sea did not significantly affect scores of Dutch submariners.

Submarine medicine: An overview of the unique challenges, medical concerns, and gaps.

Submariners face many challenges. For example, they "live where they work" and can be called to duty anytime. They have limited access to open space, natural settings, fresh air, fresh food, sunlight, privacy, exercise, and outside communication. They support a wider range of missions than occur aboard most other Navy vessels. At sea or on shore, submariners work long hours under conditions with little margin for error. They may traverse remote or disputed areas of the ocean far from rescue assets, and must remain vigilant for potential encounters with hostile forces, onboard fires, anomalies in the breathing atmosphere, leaks, undersea collisions, or radiation exposures. If any of these factors cause casualties, the Independent Duty Corpsman (with intermittent advice from shore-based medical personnel), must be ready to provide aid as long as necessary. The challenges of submarine service led to the growth of the unique field of submarine medicine, which has maintained an excellent record of health and safety. This review introduces the field of submarine medicine as practiced in the U.S. Navy, describing its major concerns, giving an overview of the operation of a submarine medical department, and identifying several medical gaps that researchers are working to fill. Submarine medicine already has a stellar record in terms of radiation and atmospheric safety and has made strides in fatigue management. Ongoing work will deliver improved psychological screening and support tools. This report summarizes developments in these and other areas of submarine medicine.

Forensic Identification of Diving Deaths. / 潜水死亡的法医学鉴定.

Investigation of the cause of death during diving is one of the contents of forensic pathology. In this article, relevant foreign literature is reviewed to summarize the techniques and methods used in the identification of diving deaths, such as accident reconstruction, diving monitoring data, postmortem CT examination and gas analysis (location and quantity) in the body of the corpse, in order to provide a reference for forensic identification of such cases.

Forensic Identification of Diving Deaths / 法医学杂志

Investigation of the cause of death during diving is one of the contents of forensic pathology. In this article, relevant foreign literature is reviewed to summarize the techniques and methods used in the identification of diving deaths, such as accident reconstruction, diving monitoring data, postmortem CT examination and gas analysis (location and quantity) in the body of the corpse, in order to provide a reference for forensic identification of such cases.

Thermal stress inside a disabled submarine.

BACKGROUND: Submarine operations require strict adherence to standard operating and safety procedures and errors in judgement or accidents could lead to catastrophe and impair the submarine's ability to surface. In case of disablement of a submarine (DISSUB), the crew would have to survive inside the submarine for a variable period awaiting rescue. Microclimate and habitability of the submarine would have to be maintained and crew would have to consume emergency rations and water. METHODS: In order to validate these procedures, a simulation was carried out in which 80 crew members were closed up inside a submarine in harbour for 24 h simulating a DISSUB situation without power and ventilation. RESULTS: Average temperature of the submarine compartments rose from 29.33 °C at the beginning of the simulation to 33.5 °C at the end of 24 h. Relative humidity increased from 79% to 87.67%. Crew members consumed an average to 973 kcal worth of rations during the 24 h of the exercise with 500 ml water. CONCLUSION: Submarine crew could survive successfully inside a disabled submarine awaiting rescue if thermal stress could be addressed. In the present simulation, the crew suffered from effects of thermal stress. Thermal stress would not only affect damage control capabilities, but could also lead the crew into earlier escape. Greater research and further studies are required to mitigate thermal stress and its effects in order to prolong survival.

Application of asymmetric physiologically inert gas kinetics in diving decompression calculation / 军事医学

Objective To explore the application of asymmetric kinetics of physiological inert gases in diving decompression algorithm.Methods Considering that the actual desaturation in the human body was slower than the saturation process,the kinetic equations of different saturation and desaturation rate of inert gases were constructed with piecewise functions on the basis of the original single exponential kinetic equation.The results were compared other adjustment methods.Results With the application of asymmetric kinetics, the time at each decompression stop was prolonged for an approximately equal proportion, remained unchanged at some deeper and shorter stops.Conclusion Asymmetric kinetics can more closely simulate the gas movement in the body to effectively control the conservativeness of decompression,and adapt to different decompression requirements by adjusting the half-saturation time ratio.

Optimization of gradient factors in normal decompression algorithm / 军事医学

Objective To optimize the application principles of gradient factors(GFs) in decompression algorithm by analyzing its law of regulation.Methods The saturated value of compartments was listed and the limits of decompression were calculated to evaluate the effect of GFs on safety and efficiency of decompression.The anchor point of GFs was changed.Results and Conclusion A higher GF was recommended in shallow and short dives, while in deep and long dives a moderate low GF and decompression by oxygen was preferred.The modification of the anchor points of GFs can increase the risk of decompression sickness and should be used with caution.

Research progress of research of pulmonary oxygen toxicity / 解放军医学杂志

Hyperbaric oxygen has been widely used in the treatment of many diseases and in some special circumstances such as deepwater diving, and it plays an irreplaceable role. But oxygen toxicity is an important complication, especially in diving medicine. Due to the characteristics of lung itself and the differences in dry/wet environment, the pathological mechanism of pulmonary oxygen toxicity is very complicated. With the advances in the experimental techniques and expansion of the research ideas, the studies on pulmonary oxygen toxicity have no longer limited to the level of tissue morphology and pathological strata, more and more studies that focused on cellular and sub-cellular levels have been carried out. The present review will focus mainly on the clinical manifestations, pathophysiology, pathogenesis and progresses in monitoring and treatment of pulmonary oxygen toxicity over recent years.

Correlation between the types of the constitution in TCM and the sleep status in PLA Navy divers / 国际中医中药杂志

Objective To investigate the correlation between the types of constitution in TCM and the sleep status in the PLA Navy divers. Methods Eighty-nine PLA Navy divers who performed 10m diving professional training were selected. Constitution in TCM was classified and determined by the standardized standard Constitution in Chinese Medicine Questionnaire, sleep status was evaluated by the Pittsburgh Sleep Quality Index. Results 62.9% of Navy divers were the mild constitution in TCM. The eight kinds of the biased constitution in TCM are ranked with yang deficiency, phlegm-dampness, dampness-heat, qi deficiency, yin deficiency, blood stasis, qi stagnation and special intrinsic quality. Among 78 Navy divers with good sleep quality, there were 49 divers (72.1%) with the mild constitution in TCM and 19 (27.9%) with the biased constitution in TCM. Among 21 Navy divers with poor sleep quality, there were 7 divers (33.3%) with the mild constitution in TCM (accounting for) and 14 (66.7%) with the biased constitution in TCM. For Navy divers with poor sleep quality, the sleep quality scores were positive correlated with the blood stasis constitution in TCM (r=0.481,P<0.05). Conclusion Sleep status is correlated with the types of the constitution in TCM, and regulating constitution in TCM can improve sleep quality in PLA Navy divers.

Effect of group psychological intervention on interpersonal relationship of the divers undergoing simulating 450-m diving / 解放军医学杂志

Objective To investigate the factors influencing the interpersonal relationship of the divers undergoing simulating 450-m diving in the Chinese Navy, in order to establish the psychological intervention strategies and evaluate the efficacy of the intervention, so as to provide a theoretical basis for increasing the combat effectiveness of naval forces. Methods Twenty excellent divers taking part in simulating 450-m diving from Navy units were interviewed, and the record of the interview was analyzed to find out their five common behaviors deteriorating the interpersonal relations, the attributional modes when conflicts happened and five commonly used countermeasures. The divers were divided into two groups, the experimental group and control group (10 people for each), and the experimental group was given psychological intervention. By using the sociometric method and Positive and Negative Affect Schedule(PANAS), comparison was made between experimental group and control group, and also between the pre-intervention status and the post-intervention status of each group. Results All the scores, including social distance (t=-2.61, P=0.03), index of individual social distance (t=-4.83, P=0.00) and negative emotion of PANAS (t=-0.38, P=0.03), were lower in the experimental group than in the control group, and in the experimental group these scores after the intervention were also lower than those before intervention. Conclusions Group psychological intervention has substantial effects on improving the divers' communication skills and satisfaction in interpersonal relationship. This kind of intervention can produce more positive emotion and reduce negative emotion, thus can be popularized in the Navy.

New progress in nautical medicine / 解放军医学杂志

Objective To review the research and development of nautical medicine both abroad and at home in the recent five years. Methods The research papers,reviews,reports and books both in Chinese and English concerning the nautical medicine were retrieved and searched,and the progresses,achievements and the development in this field were analyzed. Results The research in nautical medicine developed very rapidly as the improvement of the sailing technologies. Much achievement was made in recent five years in diving physiology and medicine,health services and medical prevention in maritime,search and rescue at sea,psychology of the mariners,and ergonomics in seafaring. Conclusion With much progress is in life saving appartues developments,disaster medicine at sea,research and development of marine drugs,and telemedicine at sea,the nautical medicine in China will support the Chinese Navy better in blue water.