Office of Submarine and Diving Medicine, Norwegian Armed Forces Joint Medical Services.
NUI AS, Bergen, Norway.
Undersea Hyperb Med. 2021 Second Quarter;48(2):127-147. doi: 10.22462/03.04.2021.3.
Multiday hyperbaric exposure has been shown to reduce the incidence of decompression sickness (DCS) of compressed-air workers. This effect, termed acclimatization, has been addressed in a number of studies, but no comprehensive review has been published. This systematic review reports the findings of a literature search. PubMed, Ovid Embase, The Cochrane Library and Rubicon Research Repository were searched for studies reporting DCS incidence, venous gas embolism (VGE) or subjective health reports after multiday hyperbaric exposure in man and experimental animals. Twenty-nine studies fulfilled inclusion criteria. Three epidemiological studies reported statistically significant acclimatization to DCS in compressed-air workers after multiday hyperbaric exposure. One experimental study observed less itching after standardized simulated dives. Two human experimental studies reported lower DCS incidence after multiday immersed diving. Acclimatization to DCS has been observed in six animal species. Multiday diving had less consistent effect on VGE after hyperbaric exposure in man. Four studies observed acclimatization while no statistically significant acclimatization was reported in the remaining eight studies. A questionnaire study did not report any change in self-perceived health after multiday diving. This systematic review has not identified any study suggesting a sensitizing effect of multiday diving, and there is a lack of data supporting benefit of a day off diving after a certain number of consecutive diving days. The results suggest that multiday hyperbaric exposure probably will have an acclimatizing effect and protects from DCS. The mechanisms causing acclimatization, extent of protection and optimal procedure for acclimatization has been insufficiently investigated.
多日高压暴露已被证明可降低压缩空气作业人员减压病（DCS）的发病率。这种被称为适应性的效应已在多项研究中得到探讨，但尚未发表过全面的综述。本系统评价报告了文献检索的结果。在 PubMed、Ovid Embase、The Cochrane Library 和 Rubicon Research Repository 中搜索了报告多日高压暴露后人及实验动物的 DCS 发病率、静脉气体栓塞（VGE）或主观健康报告的研究。29 项研究符合纳入标准。3 项流行病学研究报告称，多日高压暴露后，压缩空气作业人员的 DCS 发病率有统计学意义的适应性。1 项实验研究观察到标准化模拟潜水后瘙痒减轻。2 项人体实验研究报告称，多日沉浸式潜水后 DCS 发病率降低。在 6 种动物物种中观察到 DCS 的适应性。在人类高压暴露后，多日潜水对 VGE 的影响不太一致。4 项研究观察到适应性，而其余 8 项研究则没有报告有统计学意义的适应性。一项问卷调查研究报告称，多日潜水后自我感知健康没有任何变化。本系统评价尚未发现任何研究表明多日潜水具有致敏作用，也缺乏支持在一定连续潜水日后休息一天对潜水有益的数据。结果表明，多日高压暴露可能会产生适应性效应，并能预防 DCS。引起适应性的机制、保护的程度和适应性的最佳程序尚未得到充分研究。
