Pulmonary hypertensive crises following surgery for congenital heart defects in young children.

In this clinical study, 20 high risk infants and neonates were monitored to identify and characterize pulmonary hypertensive crises following surgery for congenital cardiac defects. Monitoring included right ventricular or pulmonary artery pressure catheters and transcutaneous oximetry. Eleven patients also had continuous analog recording of hemodynamic data so that antecedents of crises and the sequence of events following treatment could be reconstructed. Eleven of the 20 patients had one or more crises. Six of these ultimately died whereas 5 patients survived with aggressive vasodilator therapy. Four patients without crises but with episodic pulmonary hypertension benefitted from pulmonary vasodilator therapy to ease weaning from ventilatory support. Typically, each crisis was associated with a stress event. Crises were difficult to ablate if not rapidly treated and multiple crises would often cluster following an initial event. High dose narcotic (fentanyl) analgesia was found to be important in the postoperative management. Tolazoline and oxygen were the most consistently useful vasodilators, but isoproterenol and nitrates also played a role. Five of the children who died were examined post mortem: histologically, there was increased pulmonary arterial muscularization in 2, in none were there changes of fixed pulmonary vascular disease. The postoperative management must be individualized on the basis of monitored responses of pulmonary circulation.