ANESTHETIC MANAGEMENT OF PATIENTS UNDERGOING BILATERAL UNIFOCALIZATION

We report on the anesthetic management of eight patients undergoing un ifocalization for pulmonary atresia and ventricular septal defect with major aortopulmonary collateral arteries. Unifocalization was perform ed separately on the right and left lungs in the lateral decubitus pos ition. During unifocalization, pulmonary blood flow to the nondependen t lung is interrupted and arterial oxygenation is dependent solely on the blood flow to the dependent lung. Thus, PaO2 and SaO2 decreased si gnificantly and PaCO2 increased significantly during unifocalization, as compared with before and after unifocalization. When these values a re compared between first and second stage of unifocalization, SaO2 du ring second stage was lower than during first stage. Although PaO2, Pa CO2, and pH during second stage tended to be worse than during first s tage, the differences did not reach statistical significance. During u nifocalization, especially in second stage, to prevent deterioration o f these arterial gas variables, pulmonary blood flow had to be increas ed by frequent administration of catecholamine. In addition, bicarbona te infusion was also used to prevent progressive metabolic acidosis du e to hypoxia during unifocalization. Because anticoagulant therapy was required during unifocalization, airway bleeding was a common complic ation.