Saphenous vein homograft: a superior conduit for the systemic arterial shunt in the Norwood operation.

BACKGROUND: Excessive pulmonary blood flow increases ventricular volume work in the face of inadequate systemic cardiac output, low diastolic blood pressure, and inadequate coronary perfusion. Using the smallest available 3-mm polytetrafluoroethylene shunts have been successful, although catastrophic shunt thrombosis has occasionally been observed. To avoid thrombosis with a smaller conduit, saphenous vein homografts (SVG) were used to construct the modified Blalock-Taussig (BT) shunts. METHODS: From January 1998 to April 1999, 25 patients weighing 3.1 kg (3.0 kg or less, n = 9), at a mean age of 8.9 days, underwent stage I Norwood using an SVG BT shunt. Common heart defects were aortic atresia (n = 8), mitral atresia and double-outlet right ventricle (n = 5), and unbalanced AVC (n = 5). Mean BT shunt size was 3.2 mm, with 12 patients having shunts that were 3 mm or smaller. RESULTS: Thirty-day hospital mortality was 8% (2 of 25). No shunt thrombosis was seen, despite banding the BT shunt in 3 patients. One patient had BT revision because of an anatomic issue not directly related to the shunt material. CONCLUSIONS: Excellent results may be achieved using SVG BT shunts in the Norwood operation. This conduit seems less likely to thrombose, both acutely and chronically, allowing the use of appropriately smaller-sized shunts in small neonates.

Current results with pediatric heart transplantation.

BACKGROUND: Cardiac transplantation is an accepted treatment for children with end-stage heart failure or complex or inoperable congenital defects. METHODS: Since 1988, 95 transplants have been performed in 89 children aged 4 days to 18 years (median 6.9 years, 42 patients 0-5 years). Fifty-eight (61%) had congenital or acquired heart disease, 31 (33%) had idiopathic cardiomyopathy, and 6 (6%) were retransplants. Fifty-seven of the patients had prior cardiac surgery with a range of one to eight procedures (mean 3.4 procedures/patient). At the time of transplantation, 53 (56%) were United Network for Organ Sharing (UNOS) status I, including 23 children on mechanical ventilation and 4 with mechanical circulatory support. RESULTS: Thirty-day survival in this group was 96%. Posttransplant results showed a median time of ventilation of 1 day (mean 3.0+/-5.7 days), median duration of inotropic support of 2 days (mean 2.7+/-2.3 days), median intensive care unit (ICU) stay of 4 days (mean 6.9+/-9.6 days), and median hospitalization of 9 days (mean 14.3+/-13.9 days). Follow-up from 1 month to 10.3 years (mean 3.1 years) has demonstrated a 1-year actuarial survival of 79% and a 5-year actuarial survival of 69%. Rejection, both acute and chronic, accounted for the vast majority of deaths. CONCLUSIONS: Pediatric heart transplantation can be accomplished with excellent early survival despite multiple prior cardiac operations and relative severity of illness. Parameters such as postoperative ventilation, inotropic support, ICU stay, and hospitalization can be kept at reasonable levels with acceptable long-term results, although rejection remains a serious problem.

Use of transthoracic bioimpedance to determine cardiac output in pediatric patients.

The use of a transthoracic bioimpedance monitor to determine cardiac output was evaluated in critically ill children. The children ranged in age from 10 months to 8 yr and their height and weight ranged from the third to the 97th percentile. Each child had a thermodilution catheter in place to monitor cardiac output. The bioimpedance monitor used in this study, the NCCOM-3, required the input of a constant (L), which was obtained for each individual patient by adjusting the L setting until cardiac output measured by bioimpedance (COBI) was within 10% of cardiac output measured by thermodilution (COTD). This method of determining L was superior to using either measured thoracic length or the manufacturer's guidelines to obtain L and resulted in an excellent correlation between COTD and COBI (r = .94; p less than .05; n = 59). In children less than 125 cm in height, measured thoracic length alone was inadequate to use for L but provided a good approximation of L when multiplied by 1.25. This study suggests that the use of transthoracic bioimpedance to determine cardiac output compares favorably with thermodilution techniques and it is noninvasive.

Cranial CT in children and adolescents with diabetic ketoacidosis.

To determine the effects of diabetic ketoacidosis on the brain, we studied nine consecutive patients between the ages of 6 and 17 years by performing cranial CT on three occasions: on admission, before treatment; 6-8 hr after beginning treatment; and 7 days after admission. Both the pretreatment scans and those at 6-8 hr showed significantly reduced size of the lateral and third ventricles in comparison with the 7-day scans. A comparison of the pretreatment scans with those done at 6-8 hr showed no statistically significant differences. We conclude that the cerebral swelling of diabetic ketoacidosis is usually present before treatment.