Research progression on safety verification of diving decompression procedures / 中国职业医学

@#A diving decompression procedure is a specific rule that divers should follow when they ascend and get out of water. It comes from the decompression theory and algorithm and is designed for the prevention of decompression sickness. With the ， ， development of diving technology and diving medicine the decompression procedures are constantly innovated and the new ， decompression procedure can be used in diving practice after safety verification. In principle the safety verification of ， decompression procedures should be conducted on animal experiments before human experiments and the risks of ， decompression sickness and oxygen toxicity should be systematically assessed. However the assessment methods used in ， ， ， different studies differ greatly thus it is urgent to establish a standard and universal verification system. Traditionally the risk ， ， assessment of decompression sickness and oxygen toxicity is mainly carried out by observing the incidence detecting bubbles ， theoretical calculation and lung functional test. Furthermore biochemical indicators are increasingly becoming important ， ， supplements. Due to the special underwater environment the diving operation is prone to accidents. Therefore in addition to ， verifying the safety of the new decompression procedure exploring its safety decompression limit is of great significance for the formulation of emergency decompression procedures in emergency situations. The specific approach is to shorten the decompression time and assess the safety until the critical time for detecting bubbles without the occurrence of decompression ， ， sickness is found. Future studies should continue to optimize safety assessment methods explore sensitive biochemical markers ， clarify species associations and improve verification efficiency and reliability of results.

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.

Doppler grading for decompression bubbles / 中国职业医学

Ultrasonic bubble detection has been widely used in predicting the risk of decompression sickness and evaluating the efficiency and safety of decompression procedures. Currently, the widely used SPENCER scale is conducted by using Doppler ultrasound to monitor the bubble signal in the precordial region of subjects. KM grading system is a computerized system based on Doppler ultrasound. The grading score can be converted into SPENCER bubble grading scale score and the bubble grading is precise and suitable for the motion status. On the basis of the above two methods, the KISMAN integrated severity score, extended SPENCER bubble grading and simplified Doppler bubble grading system were established. They not only coordinated analysis of Doppler ultrasound bubble detection results with other risk factors of decompression disease, but also convenient to use computer for processing detection results. With the in-depth application of Fourier technique and empirical mode decomposition in Doppler audio bubble signal detection, methods such as three-parameter fuzzy analysis and energy operator method are playing an important role in automatic bubble analysis. Optimization of detection technology and improvement of sensitivity and accuracy of automatic analysis are important development directions in the field of decompression bubble Doppler grating technology.

Factores determinantes de la accidentabilidad y enfermedades profesionales de los buzos mariscadores de caletas de la Región de Coquimbo, Chile / Determining factors of the accident rate and occupational diseases of the shellfish divers of the Coquimbo Region, Chile

RESUMEN Objetivos Identificar las causas de accidentes y enfermedades profesionales de buzos mariscadores en las caletas de Coquimbo, Los Vilos y Tongoy en la región de Coquimbo (Chile), en el periodo 2008-2018. Métodos Se aplicó una encuesta de 44 preguntas para determinar las causas o factores que influyen en los accidentes y enfermedades profesionales de los buzos mariscadores en la región. Se recopiló información, experiencias y observaciones de los protagonistas. Para su análisis se utilizaron la tabla de doble entradas, los estadísticos de asociación X2 y C de contingencia. Resultados De las 52 encuestas realizadas, 28 buzos mariscadores han tenido accidentes y enfermedades profesionales (53%). El segmento que no completa la enseñanza básica concentra el 46% de los accidentes. También muestra incidencia, la profundidad a la cual se realiza el buceo, el consumo de alcohol y tabaco, el no uso de las tablas de descompresión y el no haber recibido capacitación. Conclusiones Los tipos de accidente o enfermedades profesionales asociadas de mayor incidencia son el síndrome de descompresión y la asfixia. Ambos casos presentan una alta asociación con el consumo de alcohol y el no uso de las tablas de descomprensión.

ABSTRACT Objectives To identify the causes of accidents and occupational diseases of shell-fish divers in the small coves de Coquimbo, Los Vilos, and Tongoy, in the Coquimbo Region, Chile, in the period 2008-2018. Methods A structured survey of 44 questions was applied to determine the causes or factors that influence accidents and occupational diseases of shellfish divers in the region; collecting information, experiences and observations of the protagonists. The double entry table, the X2 and C contingency association statistics were used for the data analysis. Results Of the 52 surveys carried out, 28 shellfish divers have had accidents and occupational diseases (53%). The segment that does not complete basic education concentrates 46% of accidents. It also shows incidence, the depth at which diving is done, the consumption of alcohol and tobacco, the non-use of decompression tables and the lack of training. Conclusions The type of accident or associated occupational disease with the highest incidence is decompression syndrome and suffocation, both of which have a high association with alcohol consumption and non-use of decompression tables.

Echocardiographic grading of decompression sickness in sheep models / 中国医学影像技术

Objective: To evaluate cardiac dysfunction of sheep models with decompression sickness with M-mode echocardiography for grading diagnosis combining with auxiliary indexes. Methods: Sixteen sheep were randomly divided into group A, B and C simulating mild, moderate and severe decompression sickness and group D (controls, each n=4). DWC150 animal experimental chamber was used to intervene with decompression scheme. Sheep in group A, B and C were compressed to 200 kPa with compressed air in uniform speed and then treated with light, medium and heavy level of atmospheric pressure simulating the environmental changes of decompression sickness in the speed of 200 kPa/min. The cardiac function was evaluated with echocardiography combined with auxiliary evaluation indexes. Results: The incidence rate of decompression sickness was 83.33% (10/12), and the mortality rate was 33.33% (4/12) in experimental group. After 2 h, 6 h and 24 h's decompression, Tarlov score reduced (F=4.25, 4.98, 5.67, all P<0.05).The white blood cell count and platelet count decreased (t=4.49, 30.92, both P<0.05), prothrombin time prolonged (t=-0.56, P<0.05), fibrin degradation products and D-dimer content increased (t=-20.31, -8.15, both P<0.05) 6 h after high pressure exposure. After decompression, the ejection fraction in experimental group decreased (F=4.00, P<0.05), while the diastolic ventricular diameter ratio (right/left) increased (F=81.31, P<0.05). Conclusion: M-mode echocardiography can be used to grade decompression sickness of sheep models combining with quantitative score and auxiliary evaluation indexes.

Enfermedad descompresiva grave en buzo aficionado / Severe decompressive illness in amateur diver

RESUMEN Paciente masculino de 23 años de edad, buzo aficionado, que ingresó en el Hospital Militar "Dr. Joaquín Castillo Duany", con historia de haber realizado inmersiones profundas, dos días consecutivos, con escape a superficie sin realizar las paradas de descompresión establecidas, a la salida de la segunda inmersión. Comenzó a presentar de forma brusca calambres, pérdida total de la fuerza muscular en miembros inferiores y disminución de la fuerza muscular en miembros superiores, así como falta de aire, opresión torácica, relajación de esfínter anal y vesical e intranquilidad. Se diagnosticó enfermedad descompresiva grave o tipo II y barotrauma pulmonar. Fue reportado grave e ingresado en sala de terapia intensiva. Se realizó tratamiento recompresivo de urgencia. La evolución clínica resultó favorable sin peligro para la vida; aunque con secuelas neurológicas invalidantes(AU)

ABSTRACT We present a 23-year-old male patient, amateur diver, who came to Dr. Joaquín Castillo Duany Militar Hospital complaining of sudden cramps, total loss of muscle strength in lower limbs, decreased muscle strength in upper limbs, shortness of breath, chest tightness, anal and bladder sphincter relaxation and restlessness. He had done deep-sea dives in two consecutive days, with escape to the surface but not performing required decompression stops at the exit of the second dive. His diagnosis was severe decompression sickness or type II and pulmonary barotrauma. He is reported as severe and admitted to the intensive care unit. Urgent recompression treatment was performed. The clinical evolution was favorable without danger to life although with disabling neurological sequelae(AU)

Enfermedad descompresiva espinal: mielopatía isquémica secundaria a un accidente de buceo / Spinal cord decompression sickness: Ischemic myelopathy secondary to a diving accident

Se reporta el caso de un paciente de 34 años, buzo de profesión, hospitalizado por presentar de forma súbita confusión, debilidad generalizada, dolor intenso seguido de paraplejía y retención urinaria luego de emerger rápidamente desde una profundidad aproximada de 42 metros. El paciente fue admitido 48 horas después del evento habiendo completado dos sesiones de terapia de descompresión. Al examen se evidenció paraplejía flácida arrefléxica con nivel sensitivo a nivel de D5 global, reflejo plantar extensor bilateral y retención urinaria. En la resonancia magnética se evidenció incremento del calibre medular con alteración de señal en su diámetro anteroposterior, el cual es visto como hiperintensidad heterogénea en la secuencia T2 y STIR desde D2 hasta D11, sin dilatación del canal medular, compatible con lesión isquémica secundaria a enfermedad descompresiva. Recibió tratamiento con sesiones de cámara hiperbárica y corticoterapia (metilprednisolona 1g EV por 5días) con respuesta parcial.Se comenta la baja incidencia de esta patología enfermedad descompresiva secundaria a un accidente de buceo) y las peculiaridades de su presentación clínica.

We report the case of a 34-year-old male patient, a professional diver hospitalized in connection with a clinical picture characterized by sudden onset of disorientation, generalized weakness, intense body pain followed by sudden paraplegia and urinary retention. These manifestations occurred after a rapid ascent (10 minutes) from a depth of about 42 meters. He was admitted after having received two sessions of decompression therapy. Physical examination revealed flaccid paraplegia, bilateral extensor plantar reflex, a D5 sensitive level. Magnetic resonance imaging showed an increase in the medullar gauge with alteration of its signal, both in anterior and posterior areas, seen as a heterogeneous hyperintensity in the sequence T2 and STIR from D2 to D11, without dilatation of the spinal canal, compatible with ischemic injury. The diagnosis of ischemic myelopathy secondary to decompressive disease was made, and the patient received treatment with a hyperbaric chamber and a short course of steroids (Methylprednisolone 1g EV for 5 days) with partial response.The case is presented, and comments are made regarding the low incidence of this pathology and the variety of clinical peculiarities in its presentation.

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.

The role of mitochondrial respiratory chain in hyperbaric oxygen induced reactive oxygen species in HUVEC / 军事医学

Objective To investigate the role of mitochondrial respiratory chain (MRC) in induction of reactive oxygen species (ROS) by hyperbaric oxygen (HBO).Methods Superoxide anion (O·-2) specific fluorescence probe DHE and mitochondrial O·-2 probe Mito-SOX were used to label ROS in human umbilical vein endothelium cells(HUVEC) microscopically after HBO exposure.Results After HBO exposure, O·-2 increased (31±8)% and (137±19) % in whole cells and in mitochondria, respectively (P<0.01).These increments were suppressed by MRC complex Ⅱ inhibitor TTFA for (55±11)% in whole cells (P<0.05)and (61±8) % in mitochondria(P<0.01).Conclusion MRC may be the main source of ROS induced by HBO in HUVECs.

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.

Spinal cord injury due to diving accidents and stress among artisanal fishers / Lesão medular por mergulho e estresse em pescadores artesanais / Lesion medular por buceo y estrés en pescadores artesanales

ABSTRACT Objective: to analyze the presence and symptoms of stress among artisanal fishers who are victims of spinal cord injury. Method: this descriptive, cross-sectional and quantitative study was conducted with a non-probabilistic sample of 44 fishers, victims of spinal cord injury on the beaches of the northern coast of Rio Grande do Norte, Brazil. Data were collected using an inventory designed for adults addressing the presence and symptoms of stress, and a form addressing the participants' sociodemographic and clinical variables. Descriptive analysis considered the participants' scores. Results: all fishers were male, aged 23.87 ± 20.9 years old on average; time since the accident that caused the injury was 33.3 ± 19.31 years on average; the level of injury most frequently affected was the thoracic spine (41.8%), of which the main sequel was paraplegia (50.0%). The findings reveal stress compatible with the exhaustion phase (25.0%), followed by the resistance phase (13.6%), with the main symptoms including: insomnia, tachycardia, hypertension, and sexual problems, among others. Conclusion: the stress identified among the fishers was in the exhaustion phase and physical symptoms predominated. A spinal cord injury impacts the victim's social, occupational and family context, leading to the emergence of stress.

RESUMO Objetivo: analisar a presença e os sintomas de estresse em pescadores artesanais vítimas de lesão medular. Método: estudo descritivo, seccional e quantitativo, realizado com amostra não probabilística de 44 pescadores vitimados por lesão medular nas praias do litoral norte do Rio Grande do Norte. Os dados foram coletados por meio de aplicação de inventário sobre presença e sintomas de estresse para adultos, conteplando ainda características sociodemográficas e clínicas dos participantes. A etapa de análise considerou o escore e o somatório das respostas obtidas, utilizando-se a estatística descritiva. Resultados: todos os pescadores eram do sexo masculino, com idade média de 23,87 ± 20,9 anos; tempo médio transcorrido após o acidente de mergulho que desencadeou a lesão de 33,3 ±19,31 anos; nível medular mais acometido a coluna torácica (41,8%), tendo como principal sequela a paraplegia (50,0%) e o tempo do acidente por mergulho de 33,3 anos. Os achados remetem ao estresse compatível a fase de exaustão (25,0%), seguida de resistência (13,6%), com destaque para sintomas como insônia, taquicardia, hipertensão, dificuldade sexual, entre outros. Conclusão: constatou-se a presença de estresse entre os pesacadores na fase de exaustão, com predomímio de sintomas físicos. Evidencia-se que a lesão medular por mergulho repercute no contexto social, ocupacional e familiar da vítima, favorecendo o aparecimento de estresse.

RESUMEN Objetivo: analizar la presencia y los síntomas de estrés en pescadores artesanales víctimas de lesión medular. Método: estudio descriptivo, seccional y cuantitativo, realizado con una muestra no probabilístico de 44 pescadores víctimas de lesión medular en las playas del litoral norte de Rio Grande do Norte. Los datos fueron recolectados por medio de la aplicación de inventario sobre presencia y síntomas de estrés para adultos, contemplando aún características sociodemográficas y clínicas de los participantes. La etapa de análisis consideró el score y la suma de las respuestas obtenidas, utilizando la estadística descriptiva. Resultados: todos los pescadores eran del sexo masculino, con edad media de 23,87 ± 20,9 años, tiempo medio transcurrido después del accidente de buceo que desencadenó la lesión de 33,3 ±19,31 años; nivel medular más acometido la columna torácica (41,8%), teniendo como principal secuela la paraplejia (50,0%) y el tiempo del accidente por buceo de 33,3 años. Los hallazgos remeten al estrés compatible a la fase de cansancio (25,0%), seguida de resistencia (13,6%), con destaque para síntomas como insomnio, taquicardia, hipertensión, dificultad sexual, entre otras. Conclusión: se constató la presencia de estrés entre los pescadores en la fase de cansancio, con predominio de síntomas físicos. Se evidencia que la lesión medular por buceo repercute en el contexto social, ocupacional y familiar de la víctima, favoreciendo la aparición de estrés.

3.0 T MRI Findings in Cerebral Decompression Sickness: A Case Report

We presented a patient with cerebral decompression sickness, who showed predominant vasogenic edema on a 3.0 Tesla (3T) magnetic resonance imaging (MRI) findings, including diffusion-weighted image (DWI) and apparent diffusion coefficient (ADC) mapping. Within minutes of surfacing, he developed paresis of the right lower limb. During transport, he began shivering, followed by severe spasm that eventually progressed to a tonic-clonic seizure. Emergent hyperbaric oxygen therapy (HBOT) was performed with U.S. Navy treatment table 6A after a treatment of seizure activity. Brain MRI was performed after hyperbaric oxygen therapy to detect any cerebral lesions, which showed subcortical hyperintensity signal changes in the left fronto-parietal region on the ADC map. Overlying cortical hyperintensity on DWI sequences and cortical hypointensity on the ADC map were simultaneously observed. Moreover, these findings disappeared in a followup MRI with complete resolution of symptoms. These findings indicate that vasogenic edema can cause cerebral decompression sickness (DCS) and that 3T MRI with DWI and ADC mapping may be useful for diagnosing cerebral DCS. In addition, these findings suggest that DW-MRI may also be useful in predicting the prognosis of cerebral DCS.

Indicação de alcoolismo em pescadores vítimas de lesão medular por mergulho / Indicación del alcoholismo en pescadores víctimas de lesion en la médula espinal por submarinismo / Indication of alcoholism in fishermen victims of spinal cord injury by diving

Examine indication of alcoholism in artisanal fisher folk victims of Spinal Cord Injury (SCI) by diving through the application of the CAGE questionnaire. Method: Sectional study and analytical, with a quantitative approach, carried out between October 2013 and August 2014. The sample was composed of 44 fishermen who suffered SCI for diving. The data were collected by means of a structured script and the analysis was by descriptive statistics. Results: All were male (100.0%), aged 46 to 60 years (63.3%), 54.5% had until elementary school, lived without a mate (63.6%) and 52.3% reported having some type of occupation. As for the questionnaire question 1 CAGE, had the highest percentage of positive responses (90.9%). According to CAGE, it was found that 93.2% of fishermen had indication of alcoholism. Conclusion: The most of the participants had indication of alcoholism...

Analisar a indicação de alcoolismo em pescadores artesanais vítimas de lesão medular (LM) por mergulho por meio da aplicação do questionário CAGE. Método: Estudo seccional e analítico, com abordagem quantitativa, realizado entre outubro de 2013 e agosto de 2014. A amostra foi composta por 44 pescadores que sofreram LM por mergulho. Os dados foram coletados por meio de um roteiro estruturado e a análise foi por estatística descritiva. Resultados: Todos eram do sexo masculino (100,0%), na faixa etária de 46 a 60 anos (63,3%), 54,5% tinham até o ensino fundamental, viviam sem companheira (63,6%) e 52,3% relataram ter algum tipo de ocupação. Quanto ao questionário CAGE, a questão 1 teve o maior percentual de respostas positivas (90,9%). De acordo com o CAGE, constatou-se que 93,2% dos pescadores tinham indicação de alcoolismo. Conclusão: A maioria dos participantes possuíam indicação de alcoolismo...

Analizar la indicación del alcoholismo en los pescadores artesanales víctimas de Lesión Medular Espinal (LME) para el submarinismo por medio de la aplicación del cuestionario CAGE. Método: Estudio transversal y analítico, con un enfoque cuantitativo, realizado entre octubre de 2013 y agosto de 2014. La muestra fue constituida por 44 pescadores que sufrieron LME para el submarinismo. Los datos fueron colectados mediante un guion estructurado y el análisis fue por estadística descriptiva. Resultados: Todos eran varones (100,0%), con edad de 46 a 60 años (63,3%), el 54,5% había completado la escuela primaria, vivían sin pareja (63,6%) y 52,3 % reportó tener algún tipo de ocupación. Cuanto al cuestionario CAGE, la cuestión 1 tuvo el mayor porcentaje de respuestas positivas (90,9%). De acuerdo con lo CAGE, se encontró que el 93,2% de los pescadores tenían indicación de alcoholismo. Conclusión: La mayoría de los participantes tenían indicación de alcoholismo...

Establishment and evaluation of a swine model of diving decompression sickness / 第二军医大学学报

Objective To establish a swine model of diving decompression sickness (DCS) for applied basic research. Methods Six Bama miniature pigs underwent a simulated diving in DWC150 animal chamber with the profile of 600 kPa (30 min) exposure, followed by 600-500 kPa (1 min), 500-400 kPa (1.5 min), 400-300 kPa (2 min), 300-200 kPa (2.5 min) and 200-100 kPa (3 min) decompression. The limb motor function was detected by animal treadmill and the evoked potential of spinal cord was tested jointly to evaluate spinal cord injury of DCS. The amount of bubbles and cardio-pulmonary function were assessed by ultrasonography. The evolution of skin symptoms was observed and blood index was collected. A set of evaluating parameters were screened considering the overall behavior, histopathology, circulation and neurophysiology, bubble generation and inflammation response. Results The DCS incidence was 100% (6/6) in the present research and there was no animal death. Evoked potential and motor function underwent significant change after decompression. Cardiac ultrasonography detected substantial amount of bubbles in the venous system and the pulmonary artery index was changed. Typical skin lesions appeared. White blood cells and platelets were reduced, and the amount of D-dimer was increased. Congestion and bleeding were noticed in the lung and spinal cord. The changes of the above indicators could objectively reflect the DCS injuries, and could be used to set up an evaluation system for swine model of DCS. Conclusion Bama miniature pigs are ideal animals for DCS modelling.

A Study on Heuristic Transportation Routes of Patients with Acute Dysbarism for the Best Prognosis

PURPOSE: Acute dysbarism is a potentially lethal injury associated with environmental medicine. Therefore, prompt treatment, including transportation of victims, is important for the best prognosis. The aim of this study was to examine transportation routes of patients with acute dysbarism for the best prognosis in Korea. METHODS: Geography of South Korea was analyzed using the geographic information system (GIS). The study examined two scenarios using transportation analysis, which relies on a GIS base and pressure variation during air and ground transportation. Given the practical assumptions, we propose some heuristic transportation routes based on the simulation of altitude, transportation time, and availability of related factors. RESULTS: Currently, transportation by ground to the treatment facilities always passes high altitude areas above 152 feet. Also, available helicopters for air transportation could not approach the treatment facilities due to the limitation of flying distance and insufficiency of medical staff and treatment equipment. Altitude variation and delayed time were identified during the period of transportation by ground from Ganneung or Incheon to Tongyoung. Heuristic algorism through the above facts recommends air transport along coasts as the best method for transportation from Ganneung or Incheon to Tongyoung. CONCLUSION: In Korea, transportation by ground was not expected to result in the best prognosis for patients with acute dysbarism. Transportation by air should be considered first as the method of transportation. Also, for the best treatment of patients with acute dysbarism, additional treatment facilities need to be established in the west coast region.

Osteonecrosis disbárica de cabeza humeral en buzo pesquero tratado con artroplastia de superficie / Dysbaric osteonecrosis of humeral head in a diver treated with resurfacing arthroplasty

Describir osteonecrosis disbárica (ODB) en buzo pesquero y exponer la experiencia inédita de tratamiento con artroplastia de superficie (AS). Introducción ODB, forma de necrosis avascular secundaria a enfermedad por descompresión (EDC), cuyo tratamiento gold standard para estadios avanzados continúa siendo la artroplastia total (AT). Presentación de caso: Paciente de 49 años, buzo pesquero, antecedentes de EDC tratada el 2008 en cámara hiperbárica, con diagnóstico compatible con ODB de cabeza humeral derecha de 6 años de evolución; Constant score=29. Se realiza AS del hombro derecho, y luego de 18 meses de seguimiento se reporta una adecuada evolución clínica con remisión de la sintomatología; Constant score a 18 meses=72. Discusión: El uso de AT en el paciente joven es limitado, por lo que surge la necesidad de implementar nuevas técnicas quirúrgicas en este grupo de pacientes. Conclusión: La AS constituye una alternativa terapéutica en adultos jóvenes y activos con ODB...

Introduce and describe Dysbaric Osteonecrosis (DON) in a fishing diver patient, emphasising clinical features, use of imaging methods, and present a new experience of treatment with Resurfacing Arthroplasty (RA). Introduction: DON, a form of avascular necrosis secondary to Decompression Sickness (DCS). Total Arthroplasty (AT) remains the reference treatment for advanced stages. Case report: Male, 49 years old, fishing diver, with a history of DCS treated in a hyperbaric chamber (2008). Right humeral head DON Compatible with 6 years of onset. Constant Score=29. RA performed on right shoulder. Clinical remission of symptoms was observed after 18 months of follow-up. Constant Score at 18 months=72. Discussion: TA use in young patients is limited, so there is a need to implement new surgical techniques in this group of patients. Conclusion: RA is a therapeutic alternative in young and active subjects with DON...

Effect of N-acetylcysteine on lung and heart injury of rats with a fast floating escape induced decompression sickness / 军事医学

Objective To investigate the effect of N-acetylcysteine ( NAC) on lung and heart injury of rats with a fast floating escape induced decompression sickness .Methods Eighty male Sprague-Dawley rats were randomly and evenly divided into four groups:control group and three NAC prevention groups .The NAC groups were treated with different doses of NAC(250, 500 or 1000 mg/kg)by intraperitoneal injection 1 h before entrance.In the control group, rats were given an equal volume of saline1h before entrance.The air was pressurized at the 2t/7 exponential rate to 1.5 MPa which was maintained for 4 min and then uniformly decompressed to atmospheric pressure .The extravehicular survival and pathological changes in the lung and heart tissue were detected 0.5 h after rat egress.Results The survival rate of rats treated with NAC 500 mg/kg(90%) was significantly higher than that of those treated with saline (65%)alone (P<0.05).There was large break and fusion in the structure of pulmonary alveolus of control group besides obvious erythrocyte exudation , cardiac muscle fibers edema ,and obvious denaturation and break .Conclusion NAC can play a protective role in rats with a fast floating escape induced decompression sickness by mitigating the injury to and inflammation of lung and heart tissue .

Comparison of common decompression tables for routine heliox diving / 军事医学

To meet the requirements for the development of marine resources and military operations, divers usually dive deeper than the depth at which narcosis is present during air diving.Under this condition, heliox is required for this div-ing.Sofar, some countries have developed their own decompression tables for routine heliox diving.The best-known is tables from USA and France.In the preceding century, tables of Former Soviet Union and France used for routine heliox diving were introduced into China.On the basis of both types of tables,Chinese Navy developed their own tables for this purpose. In this paper, we summarized the characteristics of these tables from 5 countries and compared them in terms of structure, oxygen use, total decompression time, first stop and other features.This may provide a basis for future modification of ta-bles used in China and the development of new tables for routine heliox diving.

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.

Pathological changes in lung tissue during fast floating escape-induced decompression sickness / 军事医学

Objective To study the pathological changes of lung tissues during fast floating escape-induced decompres-sion sickness.Methods Eighty male SD rats were randomly divided into 2 groups, 60 in fast floating escape group (escape group) , and 20 in control group .Rats in the control group were only put in a cabin under the same atmospheric pressure (ATM).Rats in escape group were pressurized to 1.5 MPa by pressure air at the 2t/7 exponential rate and stayed for 4 min till decompression.Then the rats′survival rate was observed after 0.5 h, lung tissue specimens were collected from each rat, the pathological score was taken , according to the degree of lung injury and the R language was used for statistical analysis.Results The mortality rate was 50%.Lung tissues of these rats were pathologically characterized by stromal lung thickening, edema, and hyperemia.Kruskal non-parametric test analysis found a significant difference (P=0.0016) between the two groups .Nemenyi test was used in pairwise comparison .The death and survival animals in escape group compared with the control group, the scores were significantly different (P<0.05).The scores had no significant difference between the deach and survival animal in escape group .Conclusion Decompression sickness caused by fast floating es-cape can significantly damage the blood-lung barrier to cause pulmonary edema .