Effects of atrial natriuretic peptide at a low dose on water and electrolyte metabolism during general anesthesia.

摘要

STUDY OBJECTIVE: To assess the hemodynamic, renal, and endocrine effects of small continuous doses of atrial natriuretic peptide (ANP) in patients anesthetized with sevoflurane for gastrectomy. DESIGN: Prospective randomized study. SETTING: Operating room and wards of a university hospital. PATIENTS: 20 ASA physical status I and II patients scheduled for gastrectomy. INTERVENTION: Atrial natriuretic peptide (0.05 mug/kg/min; ANP group, n = 10) or saline (control group, n = 10) was infused continuously for 2 hours beginning at the start of the operation. MEASUREMENTS: Plasma concentrations of ANP, brain natriuretic peptide, cortisol, angiotensin II, and aldosterone; plasma renin activity; serum and urinary sodium, potassium, and chloride; and urinar output. MAIN RESULTS: The ANP group showed much greater urine volume and sodium, potassium, and chloride excretion than the control group, although the ANP group had a lower arterial blood pressure. The infusion did not affect surgery-induced increases in hormones. No patients experienced excessive hypotension, bradycardia, or other perioperative complications. CONCLUSIONS: Continuous intravenous infusion of ANP at 0.05 mug/kg/min during gastrectomy was associated with greater water and electrolyte excretion unaccompanied by changes in potentially interacting hormones. Low-dose infusion may be particularly safe and useful for controlling water and electrolyte metabolism intraoperatively.