Pre-operative sildenafil and pulmonary endothelial-related complications following cardiopulmonary bypass: a randomised trial in children undergoing cardiac surgery.

ABSTRACT

In a randomised trial, we compared the effects of oral sildenafil (0.5 mg.kg(-1) ) and placebo, administered the day before cardiac surgery, in 24 children. In sildenafil vs placebo patients, pre-cardiopulmonary bypass median (IQR [range]) cyclic-guanosine-monophosphate was not significantly different (29.9 (2.1-208.1 [0.5-391.5]) vs 5.2 (0.3-54.6 [0-628.9]) pmol.ml(-1) , respectively). Post-cardiopulmonary bypass, nitrate/nitrite levels were also not significantly different (0.7 (0-8.0 [0-142.8]) vs 0 (0-2.7 [0-52.7]) µM, respectively). Postoperatively, mean (SD) pulmonary vascular resistance (2.64 (2.28) vs 1.90 (1.12) WU.m(-2) , respectively and oxygenation index (5.29 (4.60) vs 3.38 (2.54), respectively) remained unchanged, whilst oxygen delivery (57.18 (21.24) vs 74.13 (35.46) ml.min(-1) .m(-2) , respectively) and bi-ventricular systolic function (left ventricle 3.78 (0.94) vs 4.55 (1.08) cm.s(-1) , respectively; p=0.002; right ventricle 6.93 (1.47) vs 8.09 (2.25) cm.s(-1) , respectively; p<0.001) were significantly reduced in the sildenafil group. In this trial, pre-operative sildenafil did not affect postoperative pulmonary vascular resistance. There was, however, a negative impact on ventricular function and oxygenation.