Optimal Ventilation Strategies in Laparoscopic Hysterectomy

The study included 113 patients who met the criteria and underwent elective laparoscopic total hysterectomy.

In the patients in the PEEPᵢ group, a recruitment maneuver was performed after intubation and after the Trendelenburg position was given. During this maneuver, the ventilator was switched to pressure-controlled mode, the I:E ratio was increased to 1:1, FiO₂ was increased to 80%, and the respiratory rate was set to 15/min. The PEEP level was increased to 20 cmH₂O with 5 cmH₂O increments every 5 respiratory cycles, and an airway opening pressure of 40 cmH₂O was obtained.

For optimal individual PEEP titration, the dynamic compliance values observed on the ventilator monitor were recorded when the PEEP reached 20 cmH₂O. The PEEP level was decreased by 2 cmH₂O every 3 respiratory cycles, and the PEEP level at which the highest compliance value was obtained was determined. The value 2 cmH₂O above this value was set as optimal PEEP, and this value was maintained throughout the surgery. The recruitment maneuver was repeated at specified time points during the surgical procedure and upon disconnection of the ventilator circuit.

Data collection was performed at several time points; before induction (T1), only hemodynamic data were recorded. Before pneumoperitoneum, 5 minutes after induction (T2) with the patient in the supine position, 20 minutes after the onset of pneumoperitoneum (T3) in the Trendelenburg position, and 60 minutes after the onset of pneumoperitoneum (T4) mechanical ventilation and hemodynamic parameters were recorded.

Inclusion criteria

• Age ≥18 years
• Scheduled for elective laparoscopic total hysterectomy
• ASA physical status I-III
• BMI ≤30 kg/m²
• Anticipated surgical duration >2 hours

Exclusion criteria

• Pre-existing neuromuscular disorders
• NYHA class III/IV heart failure
• OSAS
• Previous lung surgery
• Severe pulmonary disease (FEV1 <50% predicted)