Preventing hypoxia, hypercapnia and gas narcosis in rebreather diving

Preventing hypoxia, hypercapnia and gas narcosis in rebreather diving

 

CIA: Professor Simon Mitchell

Exploration divers often use so-called “rebreather” underwater breathing apparatus to extend their depth range and duration.  

Project summary

Exploration divers often use so-called “rebreather” underwater breathing apparatus to extend their depth range and duration.  Rebreathers are more complicated than the simple scuba equipment  that most divers are familiar with. With this complexity comes increased risks of user error and technical failure.  

The cumulative goal of this work is real-time detection of impending 3-H events (hypoxia, hyperoxia, and hypercapnia) and narcotic impairment that may predispose to causative errors through either monitoring technologies or enhancement of diver recognition (or both). The work will afford a better understanding of the relationship between cerebral oxygenation and cognitive performance in human subjects, and may identify potential real-time hypoxia or hypercapnia monitoring strategies in the form of eye tracking, quantitative EEG analysis (qEEG) and functional near infrared spectroscopy (fNIRS). In the case of qEEG, this work will complete the accumulation of indicative human EEG data in exposures to gas narcosis, hyperoxia, hypoxia, and hypercapnia, facilitating the possibility of an integrative EEG-based monitoring package for all relevant gas effects / toxicities.

In addition, the results will identify (or refute) easily implemented training exposures to improve diver recognition of critical 3-H events. This will also be of great interest to the military and civilian aviation communities who already conduct hypoxia exposures for this purpose largely without evidence of efficacy.

Chief investigators

Professor Simon Mitchell, The University of Auckland, New Zealand.

Funding

The project was awarded $A70,000 through the ANZCA research grants program for 2022.   

Last updated 14:35 8.03.2022