Cardiopulmonary bypass in infants under four months of age.

Thirty infants under 4 months of age who had cardiac surgery with standard cardiopulmonary bypass were reviewed in order to assess the results and applicability of cardiopulmonary bypass in these very young infants. Their major diagnoses were as follows (deaths in parentheses): transposition of the great vessels (TGA), 9 cases (5); aortic stenosis, 5 cases (2); double-outlet right ventricle, 3 cases (3); total anomalous pulmonary venous drainage, 3 cases (one); ventricular septal defect (VSD), 3 cases (0); tetralogy of Fallot, 2 cases (one); pulmonary stenosis, 2 cases (one); atrial septal defect (ASD) with primary pulmonary hypertension, one case (one), VSD and ASD, one case (0); and dextrocardia and common atrioventricular canal, one case (0). The over-all hospital mortality rate was 46.6 per cent (14 deaths). Two deaths in the transposition group resulted from attempts to explore or close a patent ductus arteriosus (PDA). These cases might have been better managed by surface cooling and limited cardiopulmonary bypass. One case of postoperative hemorrhage and cardiac tamponade might have been partially related to the use of cardiopulmonary bypass. Four deaths were due to uncorrectable lesions, two each were related to technical errors and improper choice of operations, and one each was related to irreversible preoperative deterioration, advanced primary pulmonary hypertension, and intractable arrhythmia. Thus the deaths directly related to the use of cardiopulmonary bypass are infrequent. Standard cardiopulmonary bypass, in conjunction with mild-to-moderate hypothermia, is applicable even in small infants and gives satisfactory exposure in most routine operations. No imposition of a significant time limit is advantageous on a surgical teaching service. The so-called Kyoto technique may afford better exposure in repairs of TGA and total anomalous pulmonary venous drainage and may also facilitate concomitant repair of associated extracardiac shunts.