Effect of positive end-expiratory pressure on pulmonary compliance and pulmonary complications in patients undergoing robot-assisted laparoscopic radical prostatectomy: a randomized control trial

BACKGROUND: To observe the effects of different positive end-expiratory pressure (PEEP) ventilation strategies on pulmonary compliance and complications in patients undergoing robotic-assisted laparoscopic prostate surgery. METHODS: A total of 120 patients with the American Society of Anesthesiologists Physical Status Class I or II who underwent elective robotic-assisted laparoscopic prostatectomy were enrolled. We randomized the patients divided into divided into three groups of 40 patients each: PEEP0, PEEP5, or PEEP10. Master Anesthetist used volume control ventilation intraoperatively with an intraoperative deep muscle relaxation strategy. Respiratory mechanics indexes were recorded at six time-points: 10 mimuts after anaesthesia induction, immediately after pneumoperitoneum establishment, 30 min, 60 min, 90 min, and at the end of pneumoperitoneum. Arterial blood gas analysis and oxygenation index calculation were performed 10 mimuts after anaesthesia induction, 60 mimuts after pneumoperitoneum, and after tracheal extubation. Postoperative pulmonary complications were also recorded. RESULTS: After pneumoperitoneum, peak inspiratory pressure (Ppeak), plateau pressure (Pplat), mean pressure (Pmean), driving pressure (ΔP), and airway resistance (Raw) increased significantly, and pulmonary compliance (Crs) decreased, persisting during pneumoperitoneum in all groups. Between immediately after pneumoperitoneum establishment, 30 min, 60 min, and 90 min, pulmonary compliance in the 10cmH(2)OPEEP group was higher than in the 5cmH(2)OPEEP (P < 0.05) and 0cmH(2)OPEEP groups(P < 0.05). The driving pressure (ΔP) immediately after pneumoperitoneum establishment, at 30 min, 60 min, and 90 min in the 10cmH(2)OPEEP group was lower than in the 5cmH(2)OPEEP (P < 0.05) and 0cmH(2)OPEEP groups (P < 0.05). Sixty min after pneumoperitoneum and tracheal extubation, the PaCO(2) did not differ significantly among the three groups (P > 0.05). The oxygenation index (PaO(2)/FiO(2)) was higher in the PEEP5 group than in the PEEP0 and PEEP10 groups 60 min after pneumoperitoneum and after tracheal extubation, with a statistically significant difference (P < 0.05). In postoperative pulmonary complications, the incidence of atelectasis was higher in the PEEP0 group than in the PEEP5 and PEEP10 groups, with a statistically significant difference (p < 0.05). CONCLUSION: The use of PEEP at 5cmH(2)O during RARP increases lung compliance, improves intraoperative oxygenation index and reduces postoperative atelectasis. TRIAL REGISTRATION: This study was registered in the China Clinical Trials Registry on May 30, 2020 (Registration No. ChiCTR2000033380). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-022-01869-1.