Methods for Determination of Individual PEEP for Intraoperative Mechanical Ventilation Using a Decremental PEEP Trial

(1) Background: Individual PEEP settings (PEEP(IND)) may improve intraoperative oxygenation and optimize lung mechanics. However, there is uncertainty concerning the optimal procedure to determine PEEP(IND). In this secondary analysis of a randomized controlled clinical trial, we compared different methods for PEEP(IND) determination. (2) Methods: Offline analysis of decremental PEEP trials was performed and PEEP(IND) was retrospectively determined according to five different methods (EIT-based: RVD(I) method, Global Inhomogeneity Index [GI], distribution of tidal ventilation [EIT VT]; global dynamic and quasi-static compliance). (3) Results: In the 45 obese and non-obese patients included, PEEP(IND) using the RVD(I) method (PEEP(RVD)) was 16.3 ± 4.5 cm H(2)O. Determination of PEEP(IND) using the GI and EIT VT resulted in a mean difference of −2.4 cm H(2)O (95%CI: −1.2;−3.6 cm H(2)O, p = 0.01) and −2.3 cm H(2)O (95% CI: −0.9;3.7 cm H(2)O, p = 0.01) to PEEP(RVD), respectively. PEEP(IND) selection according to quasi-static compliance showed the highest agreement with PEEP(RVD) (p = 0.67), with deviations > 4 cm H(2)O in 3/42 patients. PEEP(RVD) and PEEP(IND) according to dynamic compliance also showed a high level of agreement, with deviations > 4 cm H(2)O in 5/42 patients (p = 0.57). (4) Conclusions: High agreement of PEEP(IND) determined by the RVD(I) method and compliance-based methods suggests that, for routine clinical practice, PEEP selection based on best quasi-static or dynamic compliance is favorable.