Effects of ephedrine on oxygen consumption and cardiac output.
Bolus doses of ephedrine are often used by anaesthesiologists for intraoperative hypotension. This randomized single-blind cross-over study was designed to simultaneously evaluate circulatory, respiratory and metabolic effects of intravenously given ephedrine in 12 healthy male volunteers. Oxygen uptake and carbon dioxide excretion were measured with indirect calorimetry and non-invasive transthoracic electrical bioimpedance was used for cardiac output measurements. The maximum effect on most variables was reached at 4-5 min. At 5 min after the administration of ephedrine 0.1 mg per kilogram body weight, there were significant increases in cardiac index, systolic and mean arterial blood pressure, expired minute volume, oxygen uptake and carbon dioxide excretion rates. There were no significant changes in the quotient between oxygen uptake rate and cardiac index, VO2/CI during the 30 min study period. The O2 saturation was not altered. The present study indicates that ephedrine increases oxygen demand and supply in a similar magnitude.
Rådström
M
M
Department of Anaesthesia and Intensive Care, Sahlgren University Hospital, Göteborg University, Sweden.
Bengtsson
J
J
Ederberg
S
S
Bengtsson
A
A
Loswick
A C
AC
Bengtson
J P
JP
D018663:Adrenergic Agents / Q000494:pharmacology*; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects*; D018592:Cross-Over Studies; D004809:Ephedrine / Q000494:pharmacology*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects*; D016037:Single-Blind Method
D018663:Adrenergic Agents; D004809:Ephedrine