Castagna Olivier, Regnard Jacques, Gempp Emmanuel, Louge Pierre, Brocq François Xavier, Schmid Bruno, Desruelle Anne-Virginie, Crunel Valentin, Maurin Adrien, Chopard Romain, MacIver David Hunter
Underwater Research Team (ERRSO) from the Military Biomedical Research Institute (IRBA), Toulon, France.
Laboratory of Human Motricity, Education Sport and Health, LAMHESS (EA 6312), Toulon, France.
Sports Med Open. 2018 Jan 3;4(1):1. doi: 10.1186/s40798-017-0116-x.
Immersion pulmonary edema is potentially a catastrophic condition; however, the pathophysiological mechanisms are ill-defined. This study assessed the individual and combined effects of exertion and negative pressure breathing on the cardiovascular system during the development of pulmonary edema in SCUBA divers.
Sixteen male professional SCUBA divers performed four SCUBA dives in a freshwater pool at 1 m depth while breathing air at either a positive or negative pressure both at rest or with exercise. Echocardiography and lung ultrasound were used to assess the cardiovascular changes and lung comet score (a measure of interstitial pulmonary edema).
The ultrasound lung comet score was 0 following both the dives at rest regardless of breathing pressure. Following exercise, the mean comet score rose to 4.2 with positive pressure breathing and increased to 15.1 with negative pressure breathing. The development of interstitial pulmonary edema was significantly related to inferior vena cava diameter, right atrial area, tricuspid annular plane systolic excursion, right ventricular fractional area change, and pulmonary artery pressure. Exercise combined with negative pressure breathing induced the greatest changes in these cardiovascular indices and lung comet score.
A diver using negative pressure breathing while exercising is at greatest risk of developing interstitial pulmonary edema. The development of immersion pulmonary edema is closely related to hemodynamic changes in the right but not the left ventricle. Our findings have important implications for divers and understanding the mechanisms of pulmonary edema in other clinical settings.
浸没性肺水肿可能是一种灾难性疾病；然而，其病理生理机制尚不明确。本研究评估了在水肺潜水员发生肺水肿过程中，运动和负压呼吸对心血管系统的单独及联合影响。
16名男性专业水肺潜水员在1米深的淡水游泳池中进行4次水肺潜水，分别在静息或运动状态下以正压或负压呼吸空气。使用超声心动图和肺部超声评估心血管变化及肺彗星征评分（一种间质性肺水肿的测量方法）。
无论呼吸压力如何，并在静息潜水后，超声肺彗星征评分为0。运动后，正压呼吸时平均彗星征评分升至4.2，负压呼吸时升至15.1。间质性肺水肿的发生与下腔静脉直径、右心房面积、三尖瓣环平面收缩期位移、右心室面积变化分数及肺动脉压显著相关。运动与负压呼吸相结合引起这些心血管指标和肺彗星征评分的最大变化。
运动时使用负压呼吸的潜水员发生间质性肺水肿的风险最大。浸没性肺水肿的发生与右心室而非左心室的血流动力学变化密切相关。我们的研究结果对潜水员以及理解其他临床环境中肺水肿的机制具有重要意义。
