RESULTS OF 546 BLALOCK-TAUSSIG SHUNTS PERFORMED IN 478 PATIENTS

Between 1983 and 1995, 546 Blalock-Taussig shunt procedures were perfo rmed in 472 patients: 128 (23.0%) were classical shunts, 90 of them on the same side as to the aortic arch, and 418 (77.0%) were modified sh unts, 182 on the same side of the arch. At the time of surgery, 78 pat ients were aged below one week, 270 from one week to 12 months, and 19 8 patients were over one year of age. The mean pre-operative arterial saturation (71.7%+/-16.54%) was significantly increased to 83%+/-17.9% immediately after the procedure (p=0.017). The overall hospital morta lity rate was 2.9% (16/546), with rates of 2.3% (3/128) for the classi cal, and 3.1% (13/418) for the modified shunts (p = not significant). The rate was significantly higher, however, for classical shunts when the pulmonary arterial diameter was less than 4 mm (15.4% versus zero; p=0.047), though this relationship was reversed for modified shunts ( zero versus 3.6%; p=0.338). Early mortality was significantly influenc ed by the age at surgery, 5/78 (6.4%) in patients aged below 1 week, 3 .7% between 1 week and 1 year, and 0.5% over 1 year (p=0.019). Early m ortality was also significantly increased in patients weighing 3kg or less, 8/156 (5.1%), versus 3/303 (1.0%), p=0.037. Overall, 51 shunts f ailed (9.3%), 10 early and 41 late, Early failure was significantly in creased in patients weighing 3kg or less, 8/156 (5.1%) versus 3/303 (1 .0%), p=0.016. The overall early failure rate was 1.4% (3/215) when he parin was administered intra-operatively and for 48 hours postoperativ ely, in contrast to an early failure rate of 3.4% (7/203) when heparin was not used (p=0.294). Overall rates of failure during follow-up wer e 3.1% (17/188) in heparinized patients versus 13.6% (24/177), (p=0.17 3) in non-heparinized patients. Failure of classical shunts was 10.2% (13/128), compared with 6.7% (28/418) for modified shunts (p=0.195). F ailure was more common overall if the pulmonary arterial diameter was less than 4 nun, 14.7% (9/61), as opposed to 8.7% (26/300) when the di ameter was 4 mm or greater, (p=0.144). Administration of aspirin durin g follow-up after the modified shunt procedure reduced failure from 11 % (18/163) to 6.7% (10/150), p=0.176. Classical or modified Blalock-Ta ussig shunts, either on the same side or opposite to the aortic arch, can be performed on patients of any age with minimum postoperative com plications and low operative mortality. The use of intra- and post-ope rative heparin appears to reduce the overall rate of failure, and the administration of aspirin during follow-up appears to reduce failure o f modified Blalock-Taussig shunts.