Abstract: For abdominal wall lift with pneumoperitoneum versus pneumoperitoneum, a total of 130 participants (all with low anaesthetic risk) scheduled for elective laparoscopic cholecystectomy were randomised in five trials to abdominal wall lift with pneumoperitoneum (n = 53) versus pneumoperitoneum only (n = 52). One trial which included 25 people did not state the number of participants in each group. All five trials had a high risk of bias. There was no mortality or conversion to open cholecystectomy in any of the participants in the trials that reported these outcomes. There was no significant difference in the rate of serious adverse events between the two groups (two trials; 2/29 events (0.069 events per person) versus 2/29 events (0.069 events per person); rate ratio 1.00; 95% CI 0.17 to 5.77). None of the trials reported quality of life, the proportion of people discharged as day-patient laparoscopic cholecystectomies, or pain between four and eight hours after the operation. There was no significant difference in the operating time between the two groups (four trials; 53 participants versus 54 participants; 13.39 minutes longer (95% CI 2.73 less to 29.51 minutes longer) in the abdominal wall lift with pneumoperitoneum group and 100 minutes in the pneumoperitoneum group). For abdominal wall lift versus pneumoperitoneum, a total of 774 participants (the majority with low anaesthetic risk) scheduled for elective laparoscopic cholecystectomy were randomised in 18 trials to abdominal wall lift without pneumoperitoneum (n = 332) versus pneumoperitoneum (n = 358). One trial which included 84 people did not state the number in each group. All the trials had a high risk of bias. There was no mortality in any of the trials that reported this outcome. There was no significant difference in the proportion of participants with serious adverse events (six trials; 5/172 (weighted proportion 2.4%) versus 2/171 (1.2%); RR 2.01; 95% CI 0.52 to 7.80). There was no significant difference in the rate of serious adverse events between the two groups (three trials; 5/99 events (weighted number of events per person = 0.346 events) versus 2/99 events (0.020 events per person); rate ratio 1.73; 95% CI 0.35 to 8.61). None of the trials reported quality of life or pain between four and eight hours after the operation. There was no significant difference in the proportion of people who underwent conversion to open cholecystectomy (11 trials; 5/225 (weighted proportion 2.3%) versus 7/235 (3.0%); RR 0.76; 95% CI 0.26 to 2.21). The operating time was significantly longer in the abdominal wall lift group than in the pneumoperitoneum group (16 trials; 6.87 minutes longer (95% CI 4.74 minutes to 9.00 minutes longer) in the abdominal wall lift group versus 75 minutes in the pneumoperitoneum group). There was no significant difference in the proportion of people discharged as laparoscopic cholecystectomy day-patients (two trials; 15/31 (weighted proportion 48.5%) versus 9/31 (29%); RR 1.67; 95% CI 0.85 to 3.26). Abdominal wall lift with or without pneumoperitoneum does not seem to offer an advantage over pneumoperitoneum in any of the patient-oriented outcomes for laparoscopic cholecystectomy in people with low anaesthetic risk. Hence it cannot be recommended routinely. The safety of abdominal wall lift is yet to be established. More research on the topic is needed because of the risk of bias in the included trials and because of the risk of type I and type II random errors due to the few participants included in the trials. Future trials should include people at higher anaesthetic risk. Furthermore, such trials should include blinded assessment of outcomes.

Plain-language summary: A total of 130 participants (all with low anaesthetic risk) were included in five trials which compared abdominal wall lift combined with very low pressure pneumoperitoneum and standard pneumoperitoneum. All five trials had a high risk of bias (introducing the possibility of overestimating benefits or underestimating the harms of abdominal wall lift). No-one died as a result of surgery. There was no significant difference in the rate of serious complications related to the surgery. None of the trials reported quality of life, the proportion of people discharged as laparoscopic cholecystectomy day-patients, or pain between four and eight hours after the operation. None required conversion of key-hole surgery to an open operation using a larger incision. There was no significant difference in the operating time between the two groups. Abdominal wall lift versus pneumoperitoneum  A total of 774 participants (the majority with low anaesthetic risk) who underwent planned laparoscopic cholecystectomy were included in 18 trials which compared abdominal wall lift and standard pneumoperitoneum. All the trials had a high risk of bias. No-one died as a result of the surgery. There was no significant difference in the rate of serious complications related to surgery. None of the trials reported quality of life or pain between four and eight hours after the operation. There was no significant difference in the rate of serious adverse events, the proportion of people who underwent an open operation using a larger incision, or the proportion discharged on the same day of surgery. The operating time was about seven minutes longer on average if the operation was performed using abdominal wall lift rather than pneumoperitoneum. In summary, abdominal wall lift does not seem to offer an advantage over pneumoperitoneum in any of the patient-oriented outcomes for laparoscopic cholecystectomy in people with low anaesthetic risk. Abdominal wall lift may increase costs by increasing the operating time. Hence it cannot be recommended routinely. The safety of abdominal wall lift is yet to be established. More randomised clinical trials on the topic are needed since the possibility of arriving at erroneous conclusions due to bias and due to the play of chance was high because of the design of the trials. Future trials should include people at high risk during anaesthesia. Furthermore, such trials should employ blinded assessments of outcome measures.