Vrijdag Xavier Ce, van Waart Hanna, Sleigh Jamie W, Balestra Costantino, Mitchell Simon J
Department of Anaesthesiology, University of Auckland, Auckland, New Zealand.
Deep Dive Dubai, Dubai, United Arab Emirates.
Diving Hyperb Med. 2020 Dec 20;50(4):377-385. doi: 10.28920/dhm50.4.377-385.
Critical flicker fusion frequency (CFFF) has been used in various studies to measure the cognitive effects of gas mixtures at depth, sometimes with conflicting or apparently paradoxical results. This study aimed to evaluate a novel automatic CFFF method and investigate whether CFFF can be used to monitor gas-induced narcosis in divers.
Three hyperbaric chamber experiments were performed: 1) Automated and manual CFFF measurements during air breathing at 608 kPa (n = 16 subjects); 2) Manual CFFF measurements during air and heliox breathing at sea level (101.3 kPa) and 608 kPa (n = 12); 3) Manual CFFF measurements during oxygen breathing at sea level, 142 and 284 kPa (n = 10). All results were compared to breathing air at sea level.
Only breathing oxygen at sea level, and at 284 kPa, caused a significant decrease in CFFF (2.5% and 2.6% respectively compared to breathing air at sea level. None of the other conditions showed a difference with sea level air breathing.
CFFF did not significantly change in our experiments when breathing air at 608 kPa compared to air breathing at sea level pressure using both devices. Based on our results CFFF does not seem to be a sensitive tool for measuring gas narcosis in divers in our laboratory setting.
临界闪烁融合频率（CFFF）已在各种研究中用于测量深度处气体混合物的认知效应，有时结果相互矛盾或明显自相矛盾。本研究旨在评估一种新型自动CFFF方法，并调查CFFF是否可用于监测潜水员的气体麻醉情况。
进行了三项高压舱实验：1）在608 kPa空气呼吸期间进行自动和手动CFFF测量（n = 16名受试者）；2）在海平面（101.3 kPa）和608 kPa进行空气和氦氧混合气呼吸期间进行手动CFFF测量（n = 12）；3）在海平面、142 kPa和284 kPa氧气呼吸期间进行手动CFFF测量（n = 10）。所有结果均与海平面空气呼吸进行比较。
仅在海平面和284 kPa呼吸氧气会导致CFFF显著降低（分别比海平面空气呼吸降低2.5%和2.6%）。其他条件与海平面空气呼吸均无差异。
与在海平面压力下呼吸空气相比，使用两种设备在608 kPa呼吸空气时，我们实验中的CFFF没有显著变化。根据我们的结果，在我们的实验室环境中，CFFF似乎不是测量潜水员气体麻醉的敏感工具。
