The Use of Large Doses of Adrenaline and Other Vasopressors in the Low Cardiac Output Syndrome after Cardiac Surgery—A Report of Four Cases

Abstract

Four cases are described of the use of prolonged and/or high doses of adrenaline in the treatment of the low cardiac output syndrome following cardiac surgery. Adrenaline was chosen because it produced a more favourable effect on central cardiovascular haemodynamics and myocardial metabolism when compared with isoprenaline, while its detrimental effects on renal function were less marked than those found when using noradrenaline. The renal insufficiency encountered was reversed in those cases without previous renal disease. Tachyphylaxis was demonstrated and weaning was achieved by gradual withdrawal of the vasopressor with concomitant blood volume expansion. Two cases with predominant right ventricular failure developed gross ascites and peripheral oedema, making control of fluid balance difficult. These problems are discussed with a summary of the relevant pharmacology of isoprenaline, noradrenaline, adrenaline and glucagon. The conclusions reached regarding the use and management of adrenaline infusion are given.