RESUMO
STUDY OBJECTIVE: To analyze the clinical effectiveness of the beta-1-adrenergic blocker, metoprolol. DESIGN: Prospective, observational, clinical study. SETTING: Operating room and intensive care unit of a tertiary-care teaching hospital. PATIENTS: 111 ASA physical status II, III, and IV consecutive patients who were scheduled for open abdominal nonvascular surgery. INTERVENTIONS: Patients were divided into two stratification groups: 83 (74.8%) of 111 received metoprolol, and 28 (25.2%) of 111 were controls. Within 24 to 96 hours, the drug was used parenterally in a dose of 5, 10, and 15 mg per 24 hours. Metoprolol cardioprotection was applied during the whole perioperative period, in the form of tablets in a dose of 25, 50, and 100 mg per 24 hours until the 30th postoperative day. MEASUREMENTS: During surgery, and in the first 72 postoperative hours, patients were monitored by continuous ST-T segment monitoring. A 12-lead electrocardiogram was attached immediately after surgery; on postoperative days 1, 2, and 7; and one day before discharge from the hospital. Serum troponin-T level was controlled 6, 24, and 96 hours after surgery. MAIN RESULTS: Postoperative mortality of cardiac etiology after 30 days of surgery was 1.2% (1/83) in the metoprolol group versus 7.1% (2/28) in the nonmetoprolol group (P<0.05). The causes of death in these three patients were acute myocardial infarction, congestive heart failure, and malignant arrhythmias. CONCLUSIONS: Perioperative cardioprotection significantly reduced mortality until postoperative day 30 in patients having open abdominal nonvascular surgery with general anesthesia.
