J Clin Monit Comput. 2025 Jun 27. doi: 10.1007/s10877-025-01318-7. Online ahead of print.
ABSTRACT
PURPOSE: We aimed to test a new method to determine the positive-end expiratory pressure (PEEP) that maintains the lungs open after a recruitment maneuver (RM).
METHODS: In eleven anesthetized patients, we compared the standard RM searching for the optimal PEEP based on the highest respiratory compliance (PEEPCrs), with a new method. This method performs a RM during a slow pressure-volume curve and detects the optimal PEEP using the novel barometric capnography curve (BCap); i.e. the plot of expired carbon dioxide versus airway pressure. The lungs’ closing pressure was detected when the slope of phase III of the BCap changed along this slow expiration (PEEPBCap). The main objective was to compare PEEPBCap with the reference PEEPCrs. As a secondary objective, we explored the association between PEEPBCap and the polarity change in end-expiratory transpulmonary pressure (PEEPPL) during the deflation phase of a slow flow PV curve.
RESULTS: We found a PEEPBCap of 8.5(3.3) cmH2O that was no statistically different from the PEEPCrs of 10.0(4.0) cmH2O (p = 0.72). Both methods correlated well with a Rho of 0.84 (p < 0.001). The Bland-Altman plot showed a bias of 0.19 and LOA of 1.92 cmH2O (95%CI -0.39 to 0.77 cmH2O). During the PV slow deflation limb, PEEPPL was 9.3(4.3), which was statistically similar to PEEPBCap (p = 0.61). Both pressures were strongly correlated (Rho = 0.93, p < 0.001) with a bias of -0.3 cmH2O and LOA of 1.52 (95%CI -0.76 to 0.16 cmH2O).
CONCLUSIONS: We concluded that BCap is feasible to detect lungs collapse using a constant flow PV curve.
PMID:40576942 | DOI:10.1007/s10877-025-01318-7
