The effect of normobaric hyperoxia on cardiac index in healthy awake volunteers.
Fifteen healthy volunteers were exposed to a stepwise increase in FIO2 between 0.21 and 1.0, and their haemodynamic responses were measured with a non-invasive transthoracic bio-impedance monitor. There was mean reduction in cardiac index from 3.44 to 3.08 l.min-1.m-2 (10.7%, p < 0.001). The mean reduction in heart rate was from 77.3 to 69.1 beats.min-1 (10.5%, p < 0.001) and the mean systemic vascular index increased from 2062 to 2221 dyne.s-1.cm-5.m-2 (7.7%, p < 0.025). There were no significant changes in stroke index or mean arterial pressure. These changes are similar quantitatively and qualitatively to those previously reported by dye dilution techniques.
Harten
J M
JM
University of Glasgow Department of Anaesthesia, Glasgow Royal Infirmary, Queen Elizabeth Building, 10 Alexandra Parade, Glasgow G31 2ER. jharten@bigfoot.com
Anderson
K J
KJ
Angerson
W J
WJ
Booth
M G
MG
Kinsella
J
J
D000328:Adult; D002302:Cardiac Output / Q000187:drug effects*; D002307:Cardiography, Impedance; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood / Q000494:pharmacology*; D010313:Partial Pressure
D010100:Oxygen