Ligation of a patent ductus arteriosus under fentanyl anesthesia improves protein metabolism in premature neonates.

BACKGROUND/PURPOSE

Although surgical ligation effectively reverses the cardiopulmonary failure associated with patent ductus arteriosus (PDA), previous findings have suggested that such surgery itself elicits a catabolic response in premature neonates. Therefore, the authors sought to quantitatively assess whether PDA ligation under fentanyl anesthesia aggravated or improved the protein metabolism of premature neonates.

METHODS

Seven ventilated, premature neonates (birth weight 815 +/- 69 g) underwent PDA ligation with standardized fentanyl anesthesia (15 microg/kg) on day-of-life 8.4 +/- 1.2 and were studied immediately pre- and 16 to 24 hours postoperatively while receiving continuous total parenteral nutrition (TPN). Whole-body protein kinetics were calculated using intravenous 1-[13C]leucine, and skeletal muscle protein breakdown was measured from the urinary 3-methylhistidine to creatinine ratio (MH:Cr).

RESULTS

Whole-body protein breakdown (10.9 +/- 1.2 v8.9 +/- 0.8 g/kg/d, P < .05), turnover (17.4 +/- 1.2 v 15.4 +/- 0.8 g/kg/d, P< .05), and MH:Cr (1.95 +/- 0.20 v 1.71 +/- 0.16 micromol:mg, P< .05) decreased significantly after operation. This resulted in a 60% improvement in protein balance (1.6 +/- 0.8 v 2.6 +/- 0.6 g/kg/d, P = 0.08) postoperatively.

CONCLUSIONS

Because of decreased whole-body protein breakdown, whole-body protein turnover, skeletal muscle protein breakdown, and increased protein accrual, surgical PDA ligation under fentanyl anesthesia promptly improves the protein metabolism of premature neonates enduring the stress of a PDA.