The impact of pneumoperitoneum and steep Trendelenburg positioning on novel oxygenation and saturation indices in robot-assisted laparoscopic prostatectomies: A prospective observational study.

Abstract

Background: Robotic-assisted laparoscopic prostatectomy (RALP) poses challenges in ventilation and oxygenation due to steep Trendelenburg positioning and pneumoperitoneum. This study aims to investigate the impact of steep Trendelenburg and pneumoperitoneum on respiratory mechanics, novel oxygenation, and saturation indices.

Methods: Mechanical ventilator, blood gas, and hemodynamic parameters were recorded for 56 RALP patients at three periods (pre-Trendelenburg, Trendelenburg and pneumoperitoneum, post-Trendelenburg). Oxygenation and saturation indices (OIs and OSIs) were calculated and compared using one-way repeated measures ANOVA with Bonferroni post hoc tests.

Results: Elastance, Pplato, Ppeak, Pmean, MP_tot, MP_dyn, DP, OI-P_mean, OI-MP_tot, OI-MP_dyn, OI-DP, OSI-P_mean, OSI-MP_tot, OSI-MP_dyn, and OSI-DP significantly increased with Trendelenburg positioning and pneumoperitoneum. Despite a reduction in the post-Trendelenburg period, these indices remained significantly elevated compared to pre-Trendelenburg levels. C_dyn, C_stat, PaO₂, PaO₂/FiO₂, and PaO₂/FiO₂*PEEP significantly decreased with Trendelenburg positioning and pneumoperitoneum.

Conclusions: In RALP, pneumoperitoneum and Trendelenburg positioning led to significant increases in respiratory mechanics (Pmean, DP, MP) and oxygenation and saturation indices (OI-P_mean, OI-MP_tot, OI-MP_dyn, OI-DP, OSI-P_mean, OSI-MP_tot, OSI-MP_dyn, OSI-DP). These new oxygenation indices may assist clinicians in optimizing the cost-gain balance in perioperative lung-protective ventilation strategies.