Cardias arrhythmias in hypoxic rabbits during aerosol propellant inhalation

Rabbits were exposed for four minutes to combinations of oxygen (21%, 11%, or 7%) and fluorocarbon-11 (0%, 5%, or 15%). Exposure to 7% oxygen-15% fluorocarbon-11 caused cardiac arrhythmias in all rabbits exposed. These bradyarrhythmias developed at levels of arterial hypoxemia that did not cause arrhythmias in rabbits exposed to 7% oxygen alone. In contrast with recent reports, hypoxia and this aerosol propellant do appear to have an interactive effect on cardiac rhythm.