Effect of pressure-controlled ventilation-volume guaranteed mode combined with individualized positive end-expiratory pressure on respiratory mechanics, oxygenation and lung injury in patients undergoing laparoscopic surgery in Trendelenburg position

The study aimed to investigate the efficacy of PCV-VG combined with individual PEEP during laparoscopic surgery in the Trendelenburg position. 120 patients were randomly divided into four groups: VF group (VCV plus 5cmH(2)O PEEP), PF group (PCV-VG plus 5cmH(2)O PEEP), VI group (VCV plus individual PEEP), and PI group (PCV-VG plus individual PEEP). P(mean), P(peak), Cdyn, PaO(2)/FiO(2), V(D)/V(T), A-aDO(2) and Qs/Qt were recorded at T(1) (15 min after the induction of anesthesia), T(2) (60 min after pneumoperitoneum), and T(3) (5 min at the end of anesthesia). The CC16 and IL-6 were measured at T(1) and T(3). Our results showed that the P(mean) was increased in VI and PI group, and the P(peak) was lower in PI group at T(2). At T(2) and T(3), the Cdyn of PI group was higher than that in other groups, and PaO(2)/FiO(2) was increased in PI group compared with VF and VI group. At T(2) and T(3), A-aDO(2) of PI and PF group was reduced than that in other groups. The Qs/Qt was decreased in PI group compared with VF and VI group at T(2) and T(3). At T(2), V(D)/V(T) in PI group was decreased than other groups. At T(3), the concentration of CC16 in PI group was lower compared with other groups, and IL-6 level of PI group was decreased than that in VF and VI group. In conclusion, the patients who underwent laparoscopic surgery, PCV-VG combined with individual PEEP produced favorable lung mechanics and oxygenation, and thus reducing inflammatory response and lung injury. Clinical Trial registry: chictr.org. identifier: ChiCTR-2100044928