The Annals of Thoracic Surgery, Vol 41, 200-203, Copyright © 1986 by The Society of Thoracic Surgeons
Pulmonary inactivation of vasopressors following cardiac operations
MS Hochberg, I Gielchinsky, V Parsonnet, SM Hussain and D Fisch
Vasoactive drugs were infused through catheters in the right atrium and
then the left atrium of 34 patients who required either vasopressor or
vasodilator support following cardiac operation to determine if the route
of infusion affected the aortic blood concentration of these agents. Drugs
were given through the right atrium for one hour and then the left atrium
for an hour. Both central aortic and pulmonary arterial blood were assayed
for drug concentrations, and hemodynamic measurements were made. Sixteen
patients receiving dopamine hydrochloride through the left atrium had a 36
+/- 12% (+/- standard error of the mean) increase in aortic concentration
of the drug (p less than 0.005) and a 37 +/- 14% increase in cardiac index
(p less than 0.005) compared with administration through the right atrium.
Seven patients receiving epinephrine showed a 59 +/- 21% increase in aortic
concentration (p less than 0.05) and a 21 +/- 10% increase in cardiac index
(p greater than 0.05, not significant). Eleven patients receiving sodium
nitroprusside achieved a 99 +/- 25% increase in aortic concentration (p
less than 0.005) and a 20 +/- 7% increase in cardiac index (p less than
0.05). In all instances, significantly higher central aortic blood
concentrations were achieved during left atrial (LA) versus right atrial
(RA) infusions. Changes in blood concentration of the drug between the
pulmonary artery and the aorta during RA infusion suggest removal or
inactivation of these drugs in the pulmonary vasculature.(ABSTRACT
TRUNCATED AT 250 WORDS)
