Effects of Pneumoperitoneum and the Steep Trendelenburg Position on Heart Rate Variability and Cerebral Oxygenation...

The aim of this study was to investigate how steep Trendelenburg positioning with pneumoperitoneum modifies brain oxygenation and autonomic nervous system modulation of heart rate variability during robotic sacrocolpopexy.

Prospective study (Canadian Task Force classification III).

Rambam Health Care Campus.

Eighteen women who underwent robotic sacrocolpopexy for treatment of uterovaginal or vaginal apical prolapse.

Robotic sacrocolpopexy.

A 5-minute computerized electrocardiogram, cerebral O₂ saturation (cSO₂), systemic O₂ saturation, heart rate (HR), diastolic blood pressure (BP), systolic BP, and end-tidal CO₂ tension were recorded immediately after anesthesia induction (baseline phase) and after alterations in positioning and in intra-abdominal pressure. HR variability was assessed in time and frequency domains. Cerebral oxygenation was measured by the technology of near-infrared spectrometry. cSO₂ at baseline was 73% ± 9%, with minor and insignificant elevation during the operation. Mean HR decreased significantly when the steep Trendelenburg position was implemented (66 ± 10 vs 55 ± 9 bpm, p < .05) and returned gradually to baseline with advancement of the operation and the decrease in intra-abdominal pressure. Concomitant with this decrease, the power of both arms of the autonomic nervous system increased significantly (2.8 ± .8 vs 3.3 ± .9 ms²/Hz and 2.5 ± 1.2 vs 3.2 ± .9 ms²/Hz, respectively, p < .05). All these effects occurred without any significant shifts in systolic or diastolic BP or in systemic or cerebral oxygenation.

This study supports the safety of robotic sacrocolpopexy performed with steep Trendelenburg positioning with pneumoperitoneum. Only minor alterations were observed in cerebral oxygenation and autonomic perturbations, which did not cause clinically significant alterations in HR rate and HR variability.