Study selection and eligibility
As shown in the flow chart (Fig.1), the search strategy initially generated 82 studies. We excluded 29 of these studies because of irrelevance or duplication. Another 46 studies were excluded because of improper study type or insufficient data after a full-text review. Finally, 7 studies met the meta-analysis’s inclusion criteria.
A total of 489 patients in 6 countries between 2006 and 2021 were included in the analysis(9, 14-19). The main characteristics of the included studies are summarized in Table 1. 182 donors underwent pure laparoscopic left lateral living donor hepatectomy (LLDH) and 307 underwent open left lateral living donor hepatectomy (OLDH) for pediatric liver transplantation. Two papers were conducted in Korea, one in France, one in Russia, one in Belgium, one in Brazil and one in Singapore. The main operative parameters analyzed included operative time, blood loss and conversion. Donor and recipient complications and hospital stay were compared for postoperative outcomes. NOS shows that the seven included studies had scores of 7 or more, demonstrating the satisfactory research quality.
Meta-analysis results
The results are presented in Figures 2-4 and summarized in Table 2 and 3.
Intraoperative and postoperative outcomes of donors
Operation time All included studies reported operation (Fig. 2a). Though no significant difference was observed between two groups, the operation time tended to be longer in the LLDH group compared to the OLDH group (WMD=17.36min, 95%CI: -13.89-48.61, P=0.28).
Blood loss Five studies reported detailed data for intraoperative blood loss between two groups (Fig. 2b). The intraoperative blood loss was significantly less in LLDH group versus OLDH group (WMD=-82.12ml, 95%CI: -109.56—54.67, P<0.00001).
Length of hospital stay Length of hospital stay was reported in five studies (Fig. 3a). Significantly shorter hospital stay was found in the LLDH group versus the OLDH group (WMD=-2.36d, 95%CI: -3.19- -1.52, P<0.00001).
Complications The complication rate was reported in all seven included studies. A reduced overall postoperative complication rate was observed in the LLDH group (OR=0.32, 95%CI: 0.15-0.68, P=0.003) (Fig. 3b). In the subgroup analysis, donor bile leakage was similar between two groups (OR=1.31, 95%CI: 0.43-4.02, P=0.63) (Suppl. Fig. 1a). Regarding to wound infection and pulmonary complications, the incidence seemed more frequent in the OLDH group than LLDH group (wound infection: OR=0.37, 95%CI: 0.11-1.25, P=0.11; pulmonary complications: OR=0.24, 95%CI: 0.04-1.41, P=0.11) (Suppl. Fig. 1b&c), though no significant difference was observed. In addition, two studies reported conversion in 4 cases of LLDH group, including middle hepatic vein injury (2 cases), hilum injury (1 case) and biliary injury (1 case).
Postoperative outcomes of recipients
All liver grafts in the included studies were successfully transplanted. Only one study reported two cases of perioperative graft failure, one in each group. The recipient perioperative mortality was comparable between two groups (OR=1.39, 95%CI: 0.47-4.15, P=0.56) (Fig. 4a). For postoperative complications of recipients, hepatic artery thrombosis, portal vein and biliary complications were most reported by included studies. There was no significant difference in overall (Fig. 4b) and independent complications between the LLDH group and OLDH group (hepatic artery thrombosis: OR=1.73, 95%CI: 0.43-6.93, P=0.44; portal vein complications: OR=1.43, 95%CI: 0.55-3.67, P=0.47; biliary complications: OR=1.2, 95%CI: 0.64-2.25, P=0.57) (Suppl. Fig. 2a-c).