Vascular dysfunction following breath-hold diving.

This study focused on vascular damage and its potential role in the genesis of DCS in breath-hold diving. Eleven breath-hold divers participated in a field study comprising eight deep breath-hold dives with short surface periods, and repetitive breath-hold dives lasting for six hours. Endothelium-dependent vasodilation of the brachial artery, via flow-mediated dilation (FMD), and the number of microparticles (MPs) were assessed before and after each protocol. All measures were analyzed by two-way within-subject analysis of variance (2x2 ANOVA; factors: time and protocol). Absolute FMD was reduced following both diving protocols (p<0.001), with no interaction (p=0.288) or main effect of protocol (p=0.151). There was a significant difference in the total number of circulating MPs between protocols (p=0.007), where both increased post-dive (p=0.012). The number of CD31+/CD41- and CD66b+ MP subtypes, although different between protocols (p<0.001), also increased by 41.0±56.6% (p=0.050) and 60.0±53.2% (p=0.045) following deep and repetitive breath-hold dives, respectively. Both deep and repetitive breath-hold diving leads to endothelial dysfunction that may play an important role in the genesis of neurological DCS. PMID: 31505129 [PubMed - as supplied by publisher]
Source: Canadian Journal of Physiology and Pharmacology - Category: Drugs & Pharmacology Authors: Tags: Can J Physiol Pharmacol Source Type: research