EFFECT OF PROPHYLACTIC USE OF FUROSEMIDE ON RENAL-FUNCTION DURING OPEN-HEART SURGERY

Abstract

Patients (45) who underwent open heart surgery were divided into a short-perfusion group (SPG, 21 patients) with a perfusion time shorter than 60 min and a long-perfusion group (LPG, 24 patients) with a perfusion time longer than 60 min. Nine patients in the SPG and 13 in the LPG received furosemide, 20-60 mg, prophylactically prior to the perfusion. During the perfusion and postoperatively all patients were given furosemide when necessary, i.e., when the volume for diuresis per hour declined below 40 ml/h. The patients who received prophylactic furosemide in the LPG subsequently had clearly less need for furosemide (3.9 mg/h) than the control subjects (7.9 mg/h per 3 days). The patients with furosemide prophylaxis in the LPG had significantly (P < 0.05) higher creatinine clearance and lower serum creatinine values during the postoperative night period and on the 3rd day. In perfusions lasting less than 60 min the patients with furosemide prophylaxis had significantly higher urine flow (P < 0.001), Na excretion (P < 0.001) and K excretion (P < 0.01) during bypass surgery and postoperatively compared with that of controls. The prophylactic use of furosemide had a beneficial effect on glomerular filtration rate (endogenous creatinine clearance) and postoperative serum creatinine level in LPG. In perfusion shorter than 60 min furosemide prophylaxis may be harmful owing to the increased excretion of water, Na and K.