The Cardiac Patient and General Surgery

THE PHYSICIAN called on to see a cardiac patient scheduled for general surgery should know what factors affect prognosis and what procedures will yield optimal care. Risks General anesthesia depresses myocardial function and often predisposes to arrhythmias. Although arterial Po 2 and Pco 2 may be adequately maintained during anesthesia, they may become abnormal temporarily during intubation and after extubation. Reflex adjustments to volume loss, position, and fever are depressed by anesthetics and narcotics. The risk of surgery is also a function of the duration and type of surgery. Operations in the thorax (non-cardiac) and on the great arteries have higher morbidity than surgery in the lower part of the abdomen and pelvis does. Obviously, hemorrhagic, pulmonary, thromboembolic, renal, and septic complications further tax any preexisting cardiac disability. Hemodynamic studies show that the cardiac index of patients surviving surgery usually rises and is maintained at elevated levels for several days postoperatively.