A 65-year-old man presented for resection of a tumor of the sigmoid colon. Medical history: He had hypertension, familial hypercholesterolemia, type II diabetes mellitus, and angina pectoris. A dipyridamole-thallium scan revealed an anteroseptal perfusion defect, which showed filling on the delayed image. Coronary angiography demonstrated a critical lesion of the left anterior descending coronary artery and a 50% stenosis of the proximal circumflex coronary artery. Percutaneous transluminal coronary angioplasty (PTCA) was performed successfully on the left anterior descending lesion 6 weeks prior to surgery.
General anesthesia is induced with etomidate, midazolam, and fentanyl, and maintained with oxygen, isoflurane, and fentanyl. Muscle relaxation is provided with vecuronium. During mobilization of the tumor, the heart rate increases from 70 to 120 beats per minute. The blood pressure…
