Introduction: The performance of laparoscopic cholecystectomy leads to hemodynamic and gasometric changes as well as to mechanical changes in respiration. The last phenomenon has been less studied in spite of its impact on the patient during surgery.
Objective: To study changes in chest wall compliance (Ccw) and lung compliance (CL) during laparoscopic cholecystectomy. Material and methods. Nine patients scheduled for laparoscopic cholecystectomy were enrolled. Tidal volume, plateau pressure (Pt) and esophageal (Pes) were measured and the data were used to calculate respiratory system compliance (Crs), Ccw and CL. Measurements were taken at three moments: T1, with the patients in supine decubitus position; T2, in anti-Trendelenburg position with pneumoperitoneum; T3, after withdrawal of pneumoperitoneum with the patient in supine decubitus position.
Results: Pt was seen to increase 57%, with a 100% increase in Pes when the patient was placed in anti-Trendelenburg position and pneumoperitoneum was established. Crs changed 44%, with a greater increase taking place in Ccw (52%) than in CL (32%). Baseline values for both pressure and compliance were recovered by T3.
Conclusions: Reduced respiratory compliance occurs during laparoscopic cholecystectomy mainly at the chest wall, with much less reduction taking place in the lung. Thus, intrathoracic pressure increases will be greater than transpulmonary pressure increases.