The short- and long-term effect of Blalock-Taussig shunt size on the outcome after first palliative surgery for cyanotic heart diseases

BACKGROUND AND OBJECTIVES: The Blalock–Taussig (BT) shunt is regarded a safe and effective means increasing pulmonary blood flow for cyanotic heart conditions. The evaluation of shunt size for postoperative hemodynamics and until second-stage palliation remains difficult. Our objective is to compare the effect of different shunt sizes on short- and long-term outcomes after a BT shunt surgery. DESIGN AND SETTINGS: This is a retrospective review in a tertiary care hospital. PATIENTS: The records of all patients with a modified BT shunt between January 2007 and January 2010 were reviewed. METHODS: Patients were divided into 2 groups: Group A with a BT shunt of 3.5 mm and Group B with a BT shunt of 4 mm, and their body weight was less than 4 kg. Groups were compared for the short-term outcome, which includes: intensive care unit course, intensive care unit (ICU) and hospital stay, mortality during the same admission, and the size of branch pulmonary arteries (PAs) before second surgery. RESULTS: A total of 29 (42%) patients were in Group A and 40 (58%) in Group B. There was no significant difference in the mean weight between both groups; P value .06. There was no significant difference between the 2 groups in regard to diastolic blood pressure and lactate levels by the end of the first 48 hours after surgey. Group A required longer duration of inotropes and more days of ventilation with P value .03 and .001, respectively. The mean (standard deviation) ICU and hospital stay were 10.0 (8.9) days and 17.0 (11.4) days, respectively, for Group A and 12 (8.9) days and 15 (12.9) days, respectively, for Group B with P value .7 and P value .6, respectively. Yet Group B had a better branch PA size and required lesser intervention for branch PAs in comparison to Group A. CONCLUSION: These data suggest that a smaller shunt size may have a trend toward higher morbidity. A bigger shunt size does not necessairly lead to stealing phenomena and its consequnces, and can be performed with a low risk leading to a better growth of branch PAs.