Background: PEEP and alveolar recruitment maneuvers are commonly used during laparoscopic surgery to improve respiratory mechanics and prevent atelectasis but may adversely affect cardiovascular function. We hypothesized that individualized PEEP titrated to best lung compliance would be hemodynamically well tolerated. Methods: We analyzed cardiovascular effects of individualized PEEP in subjects undergoing laparoscopic surgery. Cardiac index, mean arterial pressure (MAP), heart rate, stroke volume variation (SVV) changes were recorded during recruitment maneuvers and decremental PEEP trials. Results: Sixty-four subjects were enrolled in this study. Our findings revealed that the hemodynamic effects, including reduction in cardiac index (P < .001), mean arterial pressure (MAP) (P < .001), and increase in stroke volume variation (SVV) (P < .001), were transient, without requiring vasopressor support. Receiver operating characteristic (ROC) analysis showed that PEEP levels >17 cm H2O reduced cardiac index (area under the ROC curve = 0.594). Post hoc analysis indicated minimal cardiac index impact at PEEP levels ≤16 cm H2O (P < .001). Notably, individualized PEEP caused a reduction in cardiac index in 10 (16%) subjects and decreased MAP in 11 (17%) subjects. Mixed-effects modeling identified age as an independent predictor of MAP reduction (estimate = -0.21, P = .01). Conclusions: In subjects undergoing laparoscopic surgery, individualized PEEP levels ≤16 cm H2O generally maintain hemodynamic stability. Recruitment maneuvers and decremental PEEP trials transiently affect cardiac index, MAP, and SVV, and increasing age is associated with greater MAP sensitivity. However, individualized PEEP titration does not ensure hemodynamic neutrality in all patients, underscoring the need for multi-parameter approaches integrating both respiratory and cardiovascular monitoring.
Keywords: PEEP; alveolar recruitment maneuvers; electrical impedance tomography; hemodynamic effects; laparoscopic surgery.