To test whether lumbar Erector Spinae Plane Block (ESPB) provides superior analgesia compared to placebo in patients undergoing Percutaneous Nephrolithotomy (PCNL), using reduction in postoperative opioid consumption, delay in rescue analgesia demand and reduction of pain scores as outcome measures.

34 adult (18-60 years) ASA I and II patients undergoing unilateral PCNL were randomized into two groups (Bupivacaine and Saline) – both receiving ipsilateral ESPB at L1 vertebral level with either 20 ml 0.25% Inj. Bupivacaine or 20 ml normal saline respectively, at the start of the surgery under general anesthesia. The primary outcome measure was total 24-hour rescue opioid analgesic requirement, while time to first demand of rescue analgesic and pain scores at 2, 12 and 24 hours postoperatively were secondary outcomes.

The 24-hour requirement of rescue analgesic Tramadol was significantly lower (53.5 ± 29.6 vs 121.2 ± 51.1 mg) [mean ± SD] (P = .001) and time to first demand of rescue analgesia was more (14.1 ± 8.4 vs 6.0 ± 5.6 hours) [mean ± SD] (P = .001) in the Bupivacaine group as compared to placebo. The pain scores were significantly lower in the Bupivacaine group at 12-hour post-operatively [4 (3,4) vs 5.5 (5,6)] [median (IQR)] (P = .001), while the stone-load, surgical duration and intraoperative opioid use were comparable between the two groups and no block-related complications were noted in any patient.

Post-PCNL, ipsilateral lumbar ESPB reduced 24-hour opioid consumption and delayed time to demand for rescue analgesia as compared to placebo.