Blatteau J-E, Pény C, Pontier J-M, Gempp E, Louge P
Département de Médecine Hyperbare, Hôpital d'instruction des armées Sainte-Anne, 83800 Toulon Armées, France.
Br J Sports Med. 2008 Nov;42(11):934-6. doi: 10.1136/bjsm.2007.042226. Epub 2007 Dec 7.
Paradoxical gas embolism through right-to-left (R/L) shunts is considered as a potential cause of certain types of decompression sickness.
To assess whether 4 months of repetitive diving and strenuous exercises would lead to an increased prevalence of R/L shunting in a group of military divers.
Using a standardised contrast-enhanced transcranial Doppler technique, 17 divers were re-examined for the presence of a R/L shunt 4 months after their initial examinations. R/L shunts were classified as type I if observed only after a straining manoeuvre, and type II if present at rest.
Initial prevalence of R/L shunt was 41%: six type I shunts and one type II. At the second examination, prevalence was 47%, with the appearance of one type I shunt that was not previously present. We found no significant increase in the prevalence and size of R/L shunts.
It is speculated that diving-related phenomena, such as variations in right atrial pressures during the end stages of or events immediately after a dive could generate an R/L shunt. However, extreme conditions of repetitive diving and strenuous exercises do not cause permanent modification in R/L permeability over a period of 4 months.
通过右向左（R/L）分流的反常气体栓塞被认为是某些类型减压病的一个潜在原因。
评估4个月的重复潜水和剧烈运动是否会导致一组军事潜水员中R/L分流的患病率增加。
使用标准化的对比增强经颅多普勒技术，17名潜水员在初次检查4个月后再次接受检查，以确定是否存在R/L分流。如果仅在用力动作后观察到R/L分流，则分类为I型；如果在静息时存在，则分类为II型。
R/L分流的初始患病率为41%：6例I型分流和1例II型分流。在第二次检查时，患病率为47%，出现了1例之前不存在的I型分流。我们发现R/L分流的患病率和大小没有显著增加。
据推测，与潜水相关的现象，如潜水末期或潜水后立即发生的事件期间右心房压力的变化，可能会产生R/L分流。然而，在4个月的时间里，重复潜水和剧烈运动的极端条件不会导致R/L通透性的永久性改变。
