To compare the effects of 3 ventilation strategies during cardiopulmonary bypass (CPB) on arterial oxygenation and postoperative pulmonary complications (PPCs).

A prospective, randomized, controlled study.

A single-center tertiary teaching hospital.

One hundred twenty pediatric patients undergoing elective repair of congenital acyanotic heart diseases with CPB.

Patients were assigned randomly into 3 groups according to ventilation strategy during CPB as follows: (1) no mechanical ventilation (NOV), (2) continuous positive airway pressure (CPAP) of 5 cmH₂O, (3) low tidal volume (LTV), pressure controlled ventilation (PCV), respiratory rate (RR) 20-to-30/min, and peak inspiratory pressure adjusted to keep tidal volume (Vt) 2 mL/kg.

The PaO₂/fraction of inspired oxygen (F_IO₂) ratio and PaO₂ were higher in the 5 minutes postbypass period in the LTV group but were nonsignificant. The PaO₂/F_IO₂ ratio and PaO₂ were significant after chest closure and 1 hour after arrival to the intensive care unit with a higher PaO₂/F_IO₂ ratio and PaO₂ in the LTV group. Regarding the oxygenation index, the LTV group was superior to the NOV group at the 3 time points, with lower values in the LTV group. There were no significant differences in the predictive indices among the 3 groups, including the extubation time, and postoperative intensive care unit stays days. The incidence of PPCs did not significantly differ among the 3 groups.

Maintaining ventilation during CPB was associated with better oxygenation and did not reduce the incidence of PPCs in pediatric patients undergoing cardiac surgery.