Effects of chlorpromazine as a systemic vasodilator during cardiopulmonary bypass in neonates.
OBJECTIVE
Vasodilator use during cardiopulmonary bypass is important in pediatric cardiac surgery, but the full range of their effects on hemodynamics remains to be clarified. We studied the effects of chlorpromazine, a potent alpha-blocking agent, in neonates.


METHODS
Subjects were 60 neonates undergoing arterial switch operations for complete transposition of the great arteries with an intact ventricular septum. Of these, 37 received 2.1 to 6.5 mg/kg of chlorpromazine during cardiopulmonary bypass (CPZ group) and 23 received no vasodilator (control group). We then compared hemodynamic parameters between groups during and early after surgery.


RESULTS
The systemic vascular resistance index and mean arterial pressure during cardiopulmonary bypass were significantly lower in the CPZ group (p < 0.05), but systolic pressure 15 minutes after cessation of cardiopulmonary bypass did not differ between groups. The rise in peripheral temperature during rewarming after hypothermia was significantly higher and the acid-base status 40 minutes after cardiopulmonary bypass less acidotic in the CPZ group. Urine output during cardiopulmonary bypass was higher in the CPZ group.


CONCLUSIONS
Chlorpromazine effectively counteracts systemic vasoconstriction induced by cardiopulmonary bypass without serious side effects in neonatal cardiac surgery.
Imoto
Yutaka
Y
Department of Cardiovascular Surgery, Fukuoka Children's Hospital, Fukuoka, Japan.
Kado
Hideaki
H
Masuda
Munetaka
M
Yasui
Hisataka
H
D006348:Cardiac Surgical Procedures / Q000379:methods*; D002315:Cardiopulmonary Bypass; D002746:Chlorpromazine / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007231:Infant, Newborn; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D002746:Chlorpromazine