Beneficial effect of fenoldopam mesylate in preventing peak blood lactate level during cardiopulmonary bypass for paediatric cardiac surgery

Abstract

Objectives: To evaluate the efficacy of fenoldopam mesylate (dose 0.2 µg/kg/min) in reducing the occurrence of hyperlactataemia (i.e. peak level of blood lactate >2.0 mM/l) during cardiopulmonary bypass (CPB) in paediatric cardiac surgery. Hyperlactataemia occurring during CPB for paediatric cardiac surgery is considered an early biomarker of an increased risk of poor outcome.

Methods: This was a dose/effectiveness clinical study applying Simon's two-stage optimal design with 5% type I error rate and 90% statistical power. Following parents' written informed consent, 53 children undergoing elective cardiac surgery with CPB between March 2009 and February 2012 were enrolled. Inclusion criteria were children weighing 3-15 kg scheduled for elective cardiac surgery and with expected CPB time of 60-180 min. Patients requiring surgery with total circulatory arrest were excluded. All patients received fenoldopam infusion at a dose of 0.2 µg/kg/min from the beginning of surgery until the end of CPB.

Results: The primary end-point was the evaluation of response to fenoldopam, i.e., blood lactate levels ≤2.0 mM/l. A total of 53 children, median age 5.7 months (range 11 days to 48 months) were enrolled. In the first stage, 18 of 19 (95%) children achieved normalization of lactate values. Then the study was continued to stage II by enrolling an additional 34 patients. At study conclusion, 96.2% of patients showed normalized lactate values. Fenoldopam infusion was well tolerated in all patients. No adverse events were observed.

Conclusions: In this study, fenoldopam at a dose of 0.2 µg/kg/min was well tolerated in paediatric patients undergoing elective cardiac surgery with CPB. In 96.2% of patients, infusion of fenoldopam was associated with intraoperative blood lactate <2.0 mM/l.

Keywords: Blood lactate; Cardiopulmonary bypass; Fenoldopam mesylate; Hyperlactataemia; Paediatric cardiac surgery; Splanchnic perfusion.