Volume-controlled, pressure-controlled vs. pressure-controlled volume-guaranteed ventilations in improving respiratory dynamics during laparoscopic cholecystectomy: A prospective, randomized, comparative study

Abstract

Introduction: Pressure-controlled volume-guaranteed (PCV-VG) mode has the advantage of both volume-controlled (VCV) and pressure-controlled ventilation (PCV). Our objective is to compare gaseous exchange and lung dynamic compliance (C dyn) after pneumoperitoneum and just before desufflation in VCV, PCV, and PCV-VG mode in laparoscopic cholecystectomy (LC). Materials and Methods: A total of 105 patients undergoing LC under general anesthesia were randomly distributed to group V (received VCV), group P (PCV), and group PV (PCV-VG) as mode of ventilation. Two arterial blood samples were taken for blood gas analysis: after the pneumoperitoneum (T1) and right before abdominal desufflation (T2). Arterial partial oxygen pressure (PaO2) and carbon dioxide (PaCO2) levels, oxygen saturation (SpO2) and end-tidal carbon dioxide were compared at these two points of time between the groups. Results: C dyn was higher in group P (43.21 ± 4.4 mL/cmH2O) compared with group V (39.18 ± 3.2 mL/cmH2O) and PV (40.37 ± 2.45 mL/cmH2O) at T2 (P 0.001). PaO2 was significantly higher (P 0.001) in group P (197.50 ± 17.29 mm Hg) at T2 compared with group V (178.90 ± 23.7 mm Hg) and PV (183.47 ± 22.99 mm Hg). Furthermore, PaCO2 was also significantly higher in Group P (40.19 ± 2.92 mm Hg) compared with group V (32.57 ± 2.09 mm Hg) and group PV (34.14 ± 3.27 mm Hg). Conclusion: PaO2 and dynamic compliance are higher in pressure-controlled mode but, high PaCO2 in pressure-controlled mode indicates inadequate ventilation. Therefore, pressure controlled volume guaranteed mode can be considered as a favorable ventilation strategy during LC because dynamic compliance and PaO2 are higher than volume controlled ventilation and PaCO2 is significantly less than pressure controlled mode.