Valic Z, Duplancić D, Baković D, Ivancev V, Eterović D, Wisløff U, Brubakk A O, Dujić Z
Department of Physiology and Biophysics, University of Split School of Medicine, Split, Croatia.
Int J Sports Med. 2005 Oct;26(8):626-31. doi: 10.1055/s-2004-830379.
Venous gas emboli are frequently observed in divers even if proper decompression procedures are followed. This study was initiated to determine if pulmonary artery pressure increases in asymptomatic divers, which could increase the risk of arterial embolization due to passage of venous gas emboli from the right to the left side of the heart. Recordings of venous gas emboli and estimation of pulmonary artery pressure by non-invasive transthoracic echocardiography were applied in 10 recreational scuba diving volunteers before and 20, 40, 60, and 80 min after simulated dives to 18 m (80 min bottom time) in a hyperbaric chamber. The ratio between pulmonary artery acceleration time and right ventricular ejection time was used as an estimate of pulmonary artery pressure. None of investigated divers had signs of decompression sickness. Despite the post-dive presence of the venous gas emboli, measured in the region of the pulmonary valve annulus (mean=1.71 bubbles.cm-2, 40 min after dive), the ratio between pulmonary artery acceleration time and right ventricular ejection time did not decrease, but actually increased (from 0.43+/-0.06 to 0.49+/-0.06, 40 min after dive; p<0.05), suggesting a decrease in pulmonary artery pressure after the dive. We conclude that diving-induced venous gas bubbles do not cause significant changes in the central circulation which could increase the risk of arterial embolization.
即使遵循了适当的减压程序，潜水者中仍经常观察到静脉气体栓塞。启动这项研究是为了确定无症状潜水者的肺动脉压力是否会升高，这可能会因静脉气体栓塞从心脏右侧流向左侧而增加动脉栓塞的风险。在高压舱中，对10名休闲水肺潜水志愿者进行模拟潜水至18米（水下时间80分钟）之前以及之后20、40、60和80分钟，应用静脉气体栓塞记录和通过无创经胸超声心动图估计肺动脉压力。肺动脉加速时间与右心室射血时间的比值被用作肺动脉压力的估计值。所有接受调查的潜水者均无减压病迹象。尽管潜水后在肺动脉瓣环区域检测到静脉气体栓塞（潜水后40分钟时平均为1.71个气泡·平方厘米），但肺动脉加速时间与右心室射血时间的比值并未降低，反而升高（潜水后40分钟时从0.43±0.06升至0.49±0.06；p<0.05），表明潜水后肺动脉压力降低。我们得出结论，潜水引起的静脉气泡不会导致中心循环发生显著变化，从而增加动脉栓塞的风险。
