Efficiency and safety of quadratus lumborum block in percutaneous nephrolithotomy: a meta-analysis of randomized controlled studies

To evaluate the effect of quadratus lumborum block (QLB) for postoperative analgesia after percutaneous nephrolithotomy (PCNL), we searched Pubmed, Embase, Cochrane library, the Chinese Biomedical Literature Database, and randomized controlled trials (RCTs) assessing analgesic efficacy of QLB for PCNL are included in this meta-analysis. The related trials met the inclusion criteria were analyzed using RevMan 5.4 software, the weighted mean difference (WMD), with their corresponding 95% CI, was calculated to compare continuous variables. Nine RCTs are included in the meta-analysis showed that QLB group had significantly lower opioids consumption (WMD − 29.59 95% CI − 43.64 to − 15.55; P < 0.00001), lessen visual analog scale (VAS) after surgery 2 h (WMD − 1.35, 95% CI − 1.93 to − 0.76; P < 0.00001), 6 h (WMD − 1.47, 95% CI − 2.04 to − 0.91; P < 0.00001) 12 h (WMD − 1.75, 95% CI − 3.17 to − 0.32; P = 0.02) and 24 h (WMD − 1.4, 95% CI − 1.86 to − 0.94; P < 0.00001), shorter hospital stay(WMD − 0.7, 95% CI -1.26 to − 0.14, P < 0.00001) and reduce intestinal exhaust recovery time (WMD − 7.41, 95% CI − 9.36 to − 5.46, P < 0.00001) than in the control group. QLB offers some potential advantages in terms of opioids consumption, VAS, hospital stay and intestinal exhaust recovery time. However, good quality and large studies with long-term follow-up are warranted for further research.