An Analysis On Influencing Factors Of Acute Decompression Sickness Of Diving Fishing Operators In Dalian

Objective: Decompression sickness is a kind of systemic disease due to improper decompression after high-pressure jobs and the dissolved gases of the body exceed the limit of supersaturation and form the bubble in the blood vessels and tissue. Acute decompression sickness is happen in a short time after decompression or decompression process. Decompression sickness can be found in a variety of high-pressure environment, such as divers, caisson workers, tunnel workers, and the hyperbaric oxygen chamber pressurized cabin and the medical personnel, technical personnel and personnel submarine escape personnel , etc .Dalian is located in the southernmost tip of the Liaodong peninsula adjacent to the Yellow Sea and Bohai Sea, marine resources are very rich. With seafood aquaculture and the fishing industry developed, diving operations is one of the main operation modes. In recently years, most seafood aquaculture is private contractor, most fishing workers are paid by calculation of compensation in accordance with the workload of the diver, and many divers are informal training, lacking of health knowledge, poor awareness of personal protection, coupled with the lack of management companies, diver do not strictly enforce the operation procedures, diver diving depth and diving time increase, so incidence of decompression sickness is rising. This article makes epidemiological investigation on fishing diving operators and analyses incidence of acute decompression sickness and influencing factors on fishing diving operators in Dalian. It is aimed at providing scientific theoretical basis for the local government authorities to develop policies which are practical prevention and intervention measures to effectively control and reduce the incidence of acute decompression sickness and to protect the health of the diving fishing workers.Methods: 171 employers were surveyed with a stratified cluster sampling method in six counties along the coast in Dalian (Lvshun Area, Jinzhou, Zhuanghe area, Xigang, Ganjingzi, Changhai County). 668 male workers engaged in diving were collected and site surveys and questionnaires were carried out. The 668 questionnaires are distributed and 642 are eligible, the pass rate of the questionnaires is 96.1%.The data were input, sorted with Excel and analyzed by SPSS13.0. The factors affecting the incidence of acute decompression sickness were analyzed with Rank sum test in single-factor analysis. Logistic regression analysis was applied to determent the factors whether influence on the acute decompression sickness in multivariate analysis.Results: The 642 divers were investigated in Dalian, the annual total number of the workers diving into the water was 392,845 times and the number of acute decompression sickness occurrence was 507 times, the average annual occurrence of acute decompression sickness rate is 1.3‰; the number of incidence was 488 people, 76% of the total number, of which 261 are mild(40.6%), 91 are moderate( 14.2%), 136 are severe(21.2%).The study analyzed that operating conditions (diving depth, diving time, diving interval, diving mode) and protective measures (diving knowledge, technical training, decompression, etc.) influence on the frequency of acute decompression sickness. A single-factor analysis showed that the deeper the dive was, the longer the dive time was and the longer the dive interval time was, the higher the frequency the incidence of acute decompression sickness was happen; The workers had good knowledge before engaged in diving operations and reduced pressure strictly in standards after diving operators, the incidence rate of acute decompression sickness was lower.Multivariate analysis showed that dive depth, dive styles were the risk factors for acute decompression sickness. The deeper the dive was, the more the worker was prone to acute decompression sickness, diving depth OR = 1.112; Heavy diving submersible was relatively more susceptible to acute decompression sickness, heavy diving relative light diving OR = 3.95.Conclusions:1. The annual average rate of the acute decompression sickness is 1.3‰of diving fishing operators in the coastal six counties of Dalian area.2. The diving fishing operations violate seriously the seafood safety management regulations in Dalian. Dive frequency, diving time, diving depth are far beyond the diving safety management requirements.3. Diving depth, diving styles are the main risk factors of acute decompression sickness. The deeper diving depth was vulnerable to cause acute decompression sickness and heavy diving occurs acute decompression sickness easily comparing to light diving.