What Researchers Did
Researchers measured cardiac output, heart rate, and stroke volume in 23 healthy male Navy divers performing bicycle exercise at normal and hyperbaric pressures.
What They Found
They found a significant decrease in cardiac output, heart rate, and stroke volume at hyperbaric pressure. Cardiac output decreased by 64% from 13.9 l min-1 at normal pressure to 8.9 l min-1 at depth. Mean heart rate dropped from 104.7 min-1 to 94.0 min-1, and stroke volume decreased from 133 ml to 96 ml.
What This Means for Canadian Patients
Canadian patients involved in diving or hyperbaric occupations should be aware that hyperbaric conditions can significantly reduce cardiac output and heart rate. This physiological response could impact their endurance and safety during activities in high-pressure environments.
Canadian Relevance
This study has no direct Canadian connection.
Study Limitations
The study's findings are based on a small, specific population of healthy male Navy divers, limiting generalizability to other populations or conditions.