Perioperative effects of alpha-stat versus pH-stat strategies for deep hypothermic cardiopulmonary bypass in infants.
OBJECTIVE
In a randomized, single-center trial, we compared perioperative outcomes in infants undergoing cardiac operations after use of the alpha-stat versus pH-stat strategy during deep hypothermic cardiopulmonary bypass.


METHODS
Admission criteria included reparative cardiac surgery, age less than 9 months, birth weight 2.25 kg or more, and absence of associated congenital or acquired extracardiac disorders.


RESULTS
Among the 182 infants in the study, diagnoses included D-transposition of the great arteries (n = 92), tetralogy of Fallot (n = 50), tetralogy of Fallot with pulmonary atresia (n = 6), ventricular septal defect (n = 20), truncus arteriosus (n = 8), complete atrioventricular canal (n = 4), and total anomalous pulmonary venous return (n = 2). Ninety patients were assigned to alpha-stat and 92 to pH-stat strategy. Early death occurred in four infants (2%), all in the alpha-stat group (p = 0.058). Postoperative electroencephalographic seizures occurred in five of 57 patients (9%) assigned to alpha-stat and one of 59 patients (2%) assigned to pH-stat strategy (p = 0.11). Clinical seizures occurred in four infants in the alpha-stat group (4%) and two infants in the pH-stat group (2%) (p = 0.44). First electroencephalographic activity returned sooner among infants randomized to pH-stat strategy (p = 0.03). Within the homogeneous D-transposition subgroup, those assigned to pH-stat tended to have a higher cardiac index despite a lower requirement for inotropic agents; less frequent postoperative acidosis (p = 0.02) and hypotension (p = 0.05); and shorter duration of mechanical ventilation (p = 0.01) and intensive care unit stay (p = 0.01).


CONCLUSIONS
Use of the pH-stat strategy in infants undergoing deep hypothermic cardiopulmonary bypass was associated with lower postoperative morbidity, shorter recovery time to first electroencephalographic activity, and, in patients with D-transposition, shorter duration of intubation and intensive care unit stay. These data challenge the notion that alpha-stat management is a superior strategy for organ protection during reparative operations in infants using deep hypothermic cardiopulmonary bypass.
du Plessis
A J
AJ
Department of Cardiology, Children's Hospital, Boston, MA 02115, USA.
Jonas
R A
RA
Wypij
D
D
Hickey
P R
PR
Riviello
J
J
Wessel
D L
DL
Roth
S J
SJ
Burrows
F A
FA
Walter
G
G
Farrell
D M
DM
Walsh
A Z
AZ
Plumb
C A
CA
del Nido
P
P
Burke
R P
RP
Castaneda
A R
AR
Mayer
J E
JE
Newburger
J W
JW
D000136:Acid-Base Equilibrium; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D004569:Electroencephalography; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007036:Hypothermia, Induced; D007223:Infant; D007231:Infant, Newborn; D007430:Intraoperative Care / Q000379:methods; D011183:Postoperative Complications / Q000517:prevention & control*; D011446:Prospective Studies; D012640:Seizures / Q000517:prevention & control