半闭式潜水呼吸器的医学安全分析

Medical safety analysis of semi-closed rebreather

目的从潜水医学角度分析半闭式潜水呼吸器的潜在安全风险,为合理使用提供参考。方法根据吸入气氧分压公式,针对某型半闭式呼吸器,计算不同工作负荷不同深度条件下的吸入气氧分压。结果最大工作深度40 m,耗氧量低于0.5 L/min时,氧分压大于1.4 ata,存在氧中毒的风险;工作深度5 m,耗氧量大于2.5 L/min,吸入气氧分压低于0.18 ata,存在缺氧风险。结论半闭式潜水呼吸器有一定的优势,但由于其工作原理,存在的医学安全风险无法完全避免。本研究显示配置呼吸气体氧分压监测传感器将风险大幅降低,并且对于不能预先计划的潜水过程,不建议采用半闭式潜水呼吸器。

[Objective]To analyze the potential risks of semi-closed rebreather（SCR） based on diving medicine, provide reference for rational use.[Methods]According to the mathematical axiom for oxygen partial pressure（PO2）, the output of under separate depth and different workload（showed as oxygen uptake） of a SCR were calculated. [Results]When the max depth is 40 m and oxygen consumption under 0.5 L/min, the PO2 in the inhaling gas will exceed 1.4 ata, which suggests divers exposure to the risk of oxygen toxicity. However, when the depth is 5 m and oxygen consumption increases to 2.5 L/min the PO2 in the inhaling gas is lower than 0.18 ata, and the diver would suffer the risk of hypoxia. [Conclusion]Even this apparatus has several advantages,there are valid risks in diving using SCR because of designing principle. This study shows that the inhaling gas oxygen partial pressure monitoring sensor can reduce the risk substantially, and SCR is not recommended for unplanned diving.