Use of labetalol during anesthesia for pheochromocytoma removal.

Labetalol, an alpha and beta adrenergic blocking drug, was used during anesthesia for removal of a very large pheochromocytoma which was predominantly epinephrine secreting. The 70-year-old female patient suffered from angina pectoris and chronic bronchitis. A preoperative treatment including an alpha-adrenolytic drug was administered but beta-adrenergic blockers were avoided because of the risk of cardiac decompensation and bronchoconstriction.

Ventilation in dogs on cardiopulmonary bypass with and without lungs.

In 13 anesthetized or awake dogs, on cardiopulmonary bypass, we varied PaO2 and PaCO2 while continuously monitoring ventilatory responses and mechanics, to assess the dog's ability to maintain eupneic ventilation for any chemical drive. In a second group of 13 dogs on cardiopulmonary bypass we repeated the tests after removal of both lungs, to assess the importance of pulmonary feedback and mechanics. The VE/PO2 plot formed two hyperbolas, asymptotic to 39 Torr PO2 with lungs, and to 27 without; both intercepted zero ventilation near 200 Torr.