Can ventilation while on cardiopulmonary bypass improve post-operative lung function for patients undergoing cardiac surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether ventilation during cardiopulmonary bypass (CPB) improves post-operative lung function. Altogether 187 relevant papers were identified using the below mentioned search, 9 papers represented the best evidence to answer the question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. We conclude that a wide range of ventilatory strategies, while on cardiopulmonary bypass, have been attempted including CPAP with positive airway pressures of 5-15 cm H(2)O, high frequency low volume ventilation (with 100 breaths per min), inspired oxygen concentrations from 21% to 100% and bilateral extra-corporeal circulation using the lungs to oxygenate the blood while on bypass. While some small and transient benefits for CPAP with 10 cm H(2)O have been demonstrated, no convincing clinical benefits for any of these strategies have been shown and thus ventilation while on cardiopulmonary bypass cannot be supported as a strategy to improve post-operative lung function.