Parsons J Travis, Smith Cameron R, Zhu Jiepei, Spiess Bruce D
Department of Anesthesiology, Virginia Commonwealth University, Richmond, Virginia, USA.
Undersea Hyperb Med. 2009 May-Jun;36(3):169-81.
Formation of bubbles in tissue and vasculature from a sudden reduction in ambient pressure is likely an underlying cause of the clinical symptoms of decompression sickness (DCS). Thus, tools detecting bubbles in the vasculature may be important for evaluating DCS. Sheep were air-compressed to 6.0 ATA (30 minutes bottom time) then rapidly decompressed to the surface. A fundus camera was quickly positioned for continuous observation of the retinal vasculature. Bubbles were observed in the retinal vasculature of 25.8% (n = 31) of the sheep. Bubble onset time ranged from 5-22 minutes post-chamber and lodge time ranged from 0-70+ minutes. Bubbles were visualized mostly in the arteries of the retinal circulation. Severe vasoconstriction was captured using red-free angiography in two sheep. In two other sheep, fluorescein angiography demonstrated occluded blood flow caused by arterial gas emboli. This study demonstrates that retinal angiography is a practical tool for real-time, noninvasive detection of bubbles in the retinal circulation, a visible window to the cerebral circulation. Thus retinal angiography may prove invaluable in the early detection of arterial gas emboli in the cerebral circulation, the resolution of which is imperative to favorable neurological outcomes. This study also presents for the first time images of bubbles in the retinal circulation associated with DCS captured by a fundus camera.
环境压力突然降低导致组织和脉管系统中形成气泡，这可能是减压病（DCS）临床症状的一个潜在原因。因此，检测脉管系统中气泡的工具对于评估DCS可能很重要。将绵羊空气压缩至6.0ATA（水下停留时间30分钟），然后迅速减压至水面。迅速放置眼底相机以持续观察视网膜脉管系统。在25.8%（n = 31）的绵羊视网膜脉管系统中观察到气泡。气泡出现时间为舱内减压后5 - 22分钟，滞留时间为0 - 70多分钟。气泡大多出现在视网膜循环的动脉中。在两只绵羊中使用无赤光血管造影术捕捉到严重的血管收缩。在另外两只绵羊中，荧光素血管造影显示动脉气体栓塞导致血流阻塞。本研究表明，视网膜血管造影是一种用于实时、无创检测视网膜循环中气泡的实用工具，视网膜循环是通向脑循环的可视窗口。因此，视网膜血管造影在早期检测脑循环中的动脉气体栓塞方面可能被证明具有极高价值，而解决动脉气体栓塞对于良好的神经学结果至关重要。本研究还首次展示了通过眼底相机捕捉到的与DCS相关的视网膜循环中气泡的图像。
