Efficacy of quadratus lumborum block for analgesia in adult participants undergoing hip surgery: A meta-analysis of randomized controlled trials

Abstract

Study objectiveThis study aimed to identify the benefits of quadratus lumborum block (QLB) in terms of postoperative analgesic effects in adult participants undergoing hip surgery. DesignMeta-analysis of randomized controlled trials. SettingPrevious randomized controlled trials that evaluated the analgesic effect of QLB compared to that of no block. PatientsNine studies including 616 participants. InterventionsParticipants in the treatment group received QLB, whereas those in the control group received no block. MeasurementsOutcomes were postoperative 24-h opioid consumption (primary), 12-h/24-h visual analog scale (VAS) or numeric rating scale (NRS) pain scores, postoperative nausea and vomiting (PONV), and satisfaction. The effect size was estimated using the standardized mean difference (SMD), mean difference (MD), or risk ratio (RR) with a 95% confidence interval (CI). We used the risk of bias tool (RoB 2) to assess the risk of bias of the included studies and the GRADE approach to determine the level of certainty of the evidence. Main resultsCompared to no block, the QLB group has less opioid consumption (SMD -1.69, 95% CI -2.54 to ‐0.84; low level of certainty of the evidence). Estimated MD for morphine consumption was 24 mg. The QLB group had a lower 12-h VAS/NRS pain score (MD -1.16, 95% CI -1.82 to ‐0.51; moderate level of certainty of the evidence) and 24-h VAS/NRS pain score (MD -0.92, 95% CI -1.42 to ‐0.43; moderate level of certainty of the evidence). QLB decreased the incidence of PONV (RR 0.43, 95% CI 0.24 to 0.79; moderate level of certainty of the evidence) and increased participants' satisfaction (SMD 1.15, 95% CI 0.63 to 1.67; moderate level of certainty of the evidence). Estimated MD for satisfaction was 1.74 points of Likert scale. There were no significant adverse events associated with the QLB in any of the included trials. ConclusionOur meta-analysis showed that QLB when compared to no block clinically decreased opioid requirements, reduced PONV, and improved participants' satisfaction. QLB also seems to be significantly superior to no block in terms of pain score, but its clinical importance remains unclear.