Objective: The aim of this meta-analysis was to evaluate the effect of perineural (PN) dexamethasone on the duration of analgesia in paravertebral block (PVB). Methods: We systematically searched PubMed, Embase, Web of Science, The Cochrane Library, and CNKI up to October 2025 for relevant randomized controlled trials (RCTs) comparing PN dexamethasone to a placebo in PVB. The primary outcome was the duration of analgesia. The mean difference (MD) and the risk ratio (RR) were calculated for continuous and dichotomous outcomes, respectively. Trial sequential analysis (TSA) was also carried out to calculate the required information size (RIS). Results: Ten trials with 731 participants were included. PN dexamethasone prolonged the duration of analgesia by approximately 350 minutes compared with placebo. In the trial sequential analysis, the cumulative Z-curve crossed both the conventional boundary and the trial sequential monitoring boundary for benefit, and reached RIS. In addition, PN dexamethasone decreased Visual analogue scale (VAS) scores at 2 hours, 6 hours, 12 hours and 24 hours after surgery with lower incidence of postoperative nausea and vomiting (PONV, risk ratio RR 0.41; 95% CI 0.25 to 0.69) and less cumulative opioid consumption (MD = − 8.85; 95% CI: − 13.39 to − 4.32). Conclusion: This study suggested PN dexamethasone effectively prolongs the duration of analgesia in PVB and reduces the cumulative opioid consumption. TSA suggested that no more trials are required to confirm that PN dexamethasone effectively prolongs the duration of analgesia in PVB. Plain Language Summary: Adding Dexamethasone to Local Anesthesia Provides Longer-Lasting Pain Relief After Surgery Why was this study done? For patients having chest or abdominal surgery, doctors use a technique called a “paravertebral block”—an injection near the spine that numbs the pain nerves—to help control pain after the operation. However, the pain relief from a single injection often does not last long enough. We wanted to find out if adding a steroid medication called dexamethasone to the numbing medicine could make the pain relief last longer. What did we do and what did we find? We analyzed high-quality clinical studies on this topic, which included 10 studies and 731 patients. We compared pain relief from a paravertebral block containing dexamethasone to one containing only a saline placebo. We found that:Adding dexamethasone to the local anesthetic prolonged the effective pain relief by about 6 hours on average.Patients who received dexamethasone reported less pain during the first day after surgery.These patients needed fewer strong opioid painkillers and experienced less nausea and vomiting.Our analysis confirmed that the current evidence is sufficient, and no further trials are needed to prove that dexamethasone effectively extends the pain relief duration. What do these results mean? For patients undergoing surgeries, adding dexamethasone to the local anesthetic in a paravertebral block is an effective way to get longer-lasting pain relief after the operation. This approach helps patients reduce need for strong pain medicine, and leads to fewer side effects, supporting a faster recovery. Keywords: perineural, dexamethasone, paravertebral block, meta-analysis
Wu et al. (2026) studied this question.