Chiara Mariotti, Marcello Guarnieri, Stefano Lazzari, Rosario Losiggio, Paola Suriano, Giovanna Pedrazzini, Christian Stoppe, Lu Ke, Zhichang Wang, Alberto Zangrillo, Giovanni Landoni, Alessandro Belletti, BREATHE-CS Collaborators
Ventilation strategies in cardiac surgery remain highly heterogeneous regarding protocols and timing. Ventilation during cardiopulmonary bypass significantly reduced postoperative pulmonary complications. Postoperative noninvasive respiratory support showed a non-significant trend toward improved survival and remains hypothesis-generating. Additional evidence is required to validate these results.
BACKGROUND: Pulmonary complications occur frequently after cardiac surgery. Various intraoperative and perioperative mechanical ventilation strategies were investigated to reduce postoperative lung injury. Evidence of their benefits remains inconclusive.
METHODS: We performed a systematic review and meta-analysis of RCTs investigating ventilation strategies applied during the preoperative, intraoperative, or postoperative period of cardiac surgery requiring cardiopulmonary bypass. The primary outcome was all-cause mortality. Secondary outcomes included the rate of infections, postoperative pulmonary complications, and the duration of mechanical ventilation.
RESULTS: We identified 105 RCTs. We conducted a meta-analysis of the 39 studies suitable for quantitative synthesis. Postoperative pulmonary complications were reduced when using ventilation during cardiopulmonary bypass (risk ratio [RR]=0.87; 95% confidence interval [CI]=0.79 to 0.96; P=0.005; I2=0%, with 15 studies included). Mortality was 17/414 (4.1%) in patients receiving postoperative noninvasive respiratory support vs 24/377 (6.4%) in control group patients (RR=0.60; 95% CI=0.34 to 1.08; P=0.09; I2=0%, with five studies included). Pressure-controlled vs volume-controlled ventilation during surgery and adaptive support ventilation vs conventional ventilation in the postoperative period were not associated with improvements in primary or secondary outcomes.
CONCLUSIONS: Ventilation strategies in cardiac surgery remain highly heterogeneous regarding protocols and timing. Ventilation during cardiopulmonary bypass significantly reduced postoperative pulmonary complications. Postoperative noninvasive respiratory support showed a non-significant trend toward improved survival and remains hypothesis-generating. Additional evidence is required to validate these results.
REGISTRATION: PROSPERO registration number CRD420251057156.