['To test the hypothesis that a continuous, low-dose infusion of a loop diuretic is more efficacious and better tolerated than conventional intermittent bolus therapy in patients with severe chronic renal insufficiency (CRI).', 'Randomized, crossover clinical trial with subjects serving as their own controls.', 'The General Clinical Research Center of Indiana University Hospital, Indianapolis, Indiana.', 'Eight adult volunteers with severe stable CRI (mean creatinine clearance, 0.28 mL/s; range, 0.15 to 0.47 mL/s) were recruited from the outpatient nephrology clinics of Indiana University Medical Center.', 'On admission, diuretic drugs were withdrawn and patients were equilibrated on an 80 mmol/d sodium, 60 mmol/d potassium metabolic diet. Patients were randomized to receive a 12-mg intravenous dose of bumetanide given either as two 6-mg bolus doses separated by 6 hours or as the same total dose administered as a 12-hour continuous infusion. When sodium balance was re-established, each patient was crossed over to the alternative study limb. All patients completed both phases of the study.', 'Comparable amounts of bumetanide appeared in the urine during the study period (infusion, 912 +/- 428 micrograms; bolus, 944 +/- 421 micrograms; difference, 32 micrograms; 95% CI, -16 micrograms to 80 micrograms, P = 0.16). The continuous infusion resulted in significantly greater net sodium excretion (infusion, 236 +/- 77 mmol; bolus, 188 +/- 50 mmol; difference, 48 mmol; CI, 16 mmol to 80 mmol, P = 0.01). No patient had episodes of drug-induced myalgias during the continuous infusion compared with 3 of 8 patients with bolus therapy.'] Is loop diuretics for chronic renal insufficiency : a continuous infusion more efficacious than bolus therapy?