# The effect of two different surgical positions on pulmonary functions ın laparoscopic sleeve gastrectomies: reverse Trendelenburg vs beach chair

## TL;DR

This study compares two surgical positions during laparoscopic sleeve gastrectomy and finds that the beach chair position improves lung function, especially in patients with higher BMI.

## Contribution

The study introduces a modified beach chair position during LSG and demonstrates its benefits on pulmonary parameters in high-BMI patients.

## Key findings

- The beach chair position reduced inspiratory and peak airway pressures compared to the reverse Trendelenburg position.
- Dynamic compliance was higher in the beach chair position, particularly in patients with a BMI of 35.1 to 40.
- Surgical satisfaction was high for both positions, with no reported discomfort.

## Abstract

The aim of our study is to compare the effect of the 30° reverse Trendelenburg position combined with the beach chair position on respiratory parameters in laparoscopic sleeve gastrectomy (LSG) with the 30° reverse Trendelenburg position alone.

Fifty patients with body mass index > 30 were included in the study. The patients were divided into two groups; in the control group, the standard 30° reverse Trendelenburg. In the beach chair group, the feet were positioned at 30° flexion from the hips after a 30° RTP. For both positions, blood pressures, pulses, saturations, EtCO2, respiratory rate, inspiratory pressure (Pins), positive end-expiratory pressure (PEEP), minute volume, tidal volume, peak airway pressure (Ppeak), and dynamic compliance were recorded. In addition, the general surgeon was asked about his satisfaction with the intra-abdominal operation site view and whether he was uncomfortable with the position.

Regardless of the group, the average age of the cases was 36.7 ± 12.1 years. There was no difference between the groups in terms of age, gender, BMI, operation time, blood pressures, heart rates, EtCO2, respiratory rate, PEEP, minute volume, tidal volume, and postoperative oxygen saturation (p > 0.05). Inspiratory and peak pressure were lower and dynamic compliance was higher in the beach chair position (p < 0.05). It was observed that the beach chair position decreased inspiratory and peak pressures and increased dynamic compliances in patients with a BMI between 35.1 and 40 (p < 0.05). Surgical satisfaction was high for both positions and there was no discomfort with the position.

It was determined that the beach chair position in LSGs reduced inspiratory and peak pressures and increased dynamic compliance. These parameters were related to BMI, and the beach chair position was more positive in terms of intraoperative lung pressures and dynamic compliance, especially in patients with a BMI between 35.1 and 40.

ClinicalTrials.gov ID: NCT06402474.

The online version contains supplementary material available at 10.1007/s00464-025-11538-2.