Background. 

Pulmonary hypertension (PH) is a common complication of congenital heart disease (CHD). With early surgical intervention, outcomes have improved over the last two decades. Persistent PH, however, may still occur following surgery. Sildenafil has been shown to be beneficial for postoperative pulmonary hypertensive crises. The role of preoperative sildenafil in controlling postoperative PH is poorly elucidated. This study aimed to evaluate the effect of preoperative sildenafil on pediatric patients undergoing congenital heart surgeries. 

Methods. 

A comprehensive literature search was conducted in scientific databases. We included randomized controlled trials which assessed the effect of preoperative sildenafil in pediatric patients with CHD undergoing repair surgeries. Primary outcomes were pre- and postoperative differences in mean pulmonary arterial pressure (mPAP) and mean pulmonary artery/aortic pressure ratio (PA/Ao ratio). 

Results. 

Four studies (n = 233) were retained for the final analysis. Dose of sildenafil ranged from .3 to .5 mg/kg every 4-6 hours via oral/nasogastric route, with timing of administration varied from 1 to 2 weeks before surgery. Compared to controls, preoperative sildenafil was associated with greater reduction in postoperative mPAP (MD –5.02; 95% CI [–8.91, –1.13]) and mean PA/Ao ratio (MD –.11; 95% CI [–.17, –.06]). Shorter CPB time, ICU length of stay, and duration of mechanical ventilation were also observed in the sildenafil group. 

Conclusion. 

Preoperative sildenafil is beneficial in reducing PAP, thereby reducing the risk of postoperative PH crisis. Further studies are warranted to identify the optimal dosage and timing of administration of sildenafil in CHD patients prior to surgery.