Absence of tolerance and toxicity to high‐dose continuous intravenous furosemide in haemodynamically unstable infants after cardiac surgery

Abstract

To evaluate a high-dose continuous furosemide regimen in infants after cardiac surgery. Fifteen haemodynamically unstable infants with volume overload admitted to a paediatric intensive care unit were treated with an aggressive furosemide regimen consisting of a loading bolus (1-2 mg kg(-1)) followed by a continuous infusion at 0.2 mg kg(-1) h(-1) which was adjusted according to a target urine output of 4 ml kg(-1) h(-1). Frequent sampling for furosemide concentrations in blood and urine was done for 3 days with simultaneous assessment of sodium excretion and urine output. The mean furosemide dose was 0.22 (+/- 0.06), 0.25 (+/- 0.10) and 0.22 (+/- 0.11) mg kg(-1) h(-1) on the first, second and third day, respectively. Median urine production was 3.0 (0.6-5.3), 4.2 (1.7-6.6) and 3.9 (2.0-8.5) ml kg(-1) h(-1), respectively, on the first, second and third day of the study. The target urine production was reached at a median time of 24 (6-60) h and this was maintained during the study period. The regimen did not result in toxic serum concentrations and was haemodynamically well tolerated. High-dose continuous furosemide infusion for 72 h in haemodynamically unstable infants after cardiac surgery appears to be a safe and effective treatment for volume overload. Development of tolerance against the effects of furosemide and ototoxic furosemide concentrations were not observed.