The Effect of Flow-Controlled Ventilation on Mechanical Power in Laparoscopic Surgeries: A Comparative Analysis with Pressure Controlled Volume Guaranteed and Volume Controlled Ventilation.

OBJECTIVE

To compare mechanical power (MP) levels among flow-controlled ventilation (FCV), volume-controlled ventilation (VCV), and pressure-controlled volume-guaranteed ventilation (PCV-VG) during laparoscopic surgery and to test the hypothesis that the stable flow dynamics of FCV would reduce MP.

METHODS

Patients were divided into three groups according to the mechanical ventilation modes applied during laparoscopic surgery: PCV-VG (n=15), VCV (n=14), and FCV (n=15). MP was calculated at four timepoints: baseline (T1), post-induction (T2), during CO2 insufflation (T3), and post-insufflation (T4). The primary outcome of the study was the comparison of MP in the FCV mode with MP in the other groups during insufflation. Driving pressure (DP), plateau pressure, and peak airway pressure were also analyzed.

RESULTS

Baseline MP was highest in PCV-VG (6.9 J/min vs. 5.0 J/min in VCV and 5.1 J/min in FCV; p=0.002). During insufflation (T3), MP increased to a similar extent across groups (PCV-VG: 9.4 J/min, VCV: 8.7 J/min, FCV: 8.6 J/min), with PCV-VG showing the smallest relative rise (p<0.001). DP and plateau pressures increased during pneumoperitoneum, but Bonferroni-adjusted comparisons revealed that these were not statistically significant. PCV-VG maintained higher positive end-expiratory pressure (5 vs. 4 cmH2O, p<0.001); however, it did not significantly affect peak pressures.

CONCLUSIONS

Contrary to our hypothesis, FCV did not reduce MP more effectively than either VCV or PCV-VG. However, PCV-VG demonstrated better mitigation of insufflation-induced increases in MP, suggesting potential advantages for lung protection during laparoscopy. Further prospective studies are needed to assess clinical outcomes.