Clinical efficacy of ultrasound guided bilateral erector spinae block for single-level lumbar fusion surgery: a prospective, randomized, case-control study

Abstract

BACKGROUND CONTEXTPostoperative experience plays a vital role in patient recovery and does not depend on the type and quality of the surgical procedure alone. Non-opioid therapies have become part of the multimodal analgesic regimen for better pain control and reduced opioid-related side effects. Most recently evolved among these are the regional anesthetic techniques, such as the thoracolumbar interfascial plane (TLIP) block and the erector spinae (ESP) block. PURPOSETo assess the efficacy of ultrasound-guided (US) ESP block for postoperative analgesia after a single level lumbar spine fusion surgery compared with conventional (opioid-based) multimodal postoperative analgesia. STUDY DESIGNA prospective, randomized, controlled, and double-blinded clinical trial. PATIENT SAMPLEA 100 consecutive patients requiring single-level lumbar spinal fusion procedure were randomized into two groups- block (multimodal analgesia with US-ESP) and control (only multimodal analgesia) groups. OUTCOME MEASURESDemographic and surgical data, intra-operative blood loss, duration of surgery, total opioid consumption (TOC) and amount of muscle relaxants used were assessed. Postoperatively, the Numeric pain Rating Scale(NRS), Modified Observer's assessment of Alertness and/or Sedation Scale (MOASS) and Patient satisfaction scores were recorded every 2 hours for the first 6 hours followed by every 6 hours for 24 hours. Continuous variables were analyzed using Student's t-test, and categorical variables were analyzed using either the Chi-square test or Fisher's exact test. p-value < .05 was considered statistically significant. METHODSPatients in both groups underwent the identical protocol for pre-emptive analgesia and induction of anesthesia. Patients in the block group received the US-ESP block after induction and positioning, followed by the multimodal analgesia, while the control group received only the multimodal analgesia. RESULTSBoth groups had identical demographic backgrounds and surgical profile. TOC for 24 hours following induction was significantly lower in the block group than the control group (105.0 ± 15.15 vs 158.00 ± 23.38mcg; p < .001). The total muscle relaxant consumption during surgery was also significantly less in the block group than the control group (51.90 ± 3.17 vs 57.70 ± 5.90; p < .001). The intra-operative blood loss was significantly less (p < .001) in the block group (303.00 ± 86.55 ml) than the control group (437.00 ± 116.85 ml). Compared to the block group, the control group's pain score (NRS) was significantly higher in the first 48 hours following surgery. The MOASS score was significantly lower in the control group (4.46 ± 0.50 vs 3.82 ± 0.82; p < .001) in the immediate postoperative period. The satisfaction score was significantly higher in the block group than the control group (9.52 ± 0.65 vs 8.22 ± 0.79; p < .001). CONCLUSIONThe employed US-ESP block for single-level lumbar fusion surgery is an effective component of multimodal analgesia for reducing blood loss, total opioid consumption, and related side effects with a significant reduction of postoperative pain and higher patient satisfaction.