Comparison of analgesic efficacy of ropivacaine versus ropivacaine plus dexmedetomidine in modified thoracolumbar interfascial plane block in patients undergoing lumbar disc surgeries: A randomised controlled trial

Background and Aims: Inadequate pain control can cause a delay in recovery; hence, adequate analgesia is of much importance. The thoracolumbar interfascial plane (TLIP) block is a relatively newer block which has shown promising effects in pain control. In this study, we aim to determine the efficacy and safety of dexmedetomidine in enhancing the impact of local anaesthetic in TLIP block in patients undergoing lumbar surgeries. Methods: 60 patients aged 18–70 years were randomised to Group Plain modified TLIP block with 20 mL of 0.25% ropivacaine bilaterally with general anaesthesia (GA) and Group Dexmed (modified TLIP block with 0.25% ropivacaine along with 0.5 µg/kg dexmedetomidine bilaterally with GA). The primary outcome was to assess the total perioperative opioid consumption in the first 24 h. The secondary outcomes were to assess pain score upon arriving in the post-anaesthesia care unit, time to first analgesic need after surgery, postoperative opioid consumption in 24 h, and incidence of adverse events, including nausea and vomiting. Continuous variables were analysed using an independent t -test. The variables which had a non-normal distribution were analysed using the Mann–Whitney U test. Paired continuous data following a normal distribution were analysed using the Paired T-test. Categorical variables were analysed using the Chi-square test. The statistical analysis was performed using Jamovi 2.4. Results: The total perioperative opioid consumption in Group Plain was 653.33 standard deviation (SD): 250.4 µg and that in Group Dexmed was 523.6 (SD: 258.6 µg), with a mean difference of 129.67 95% confidence interval (CI): -1.89, 261.22 ( P = 0.053). However, the first request for analgesia was significantly prolonged in the Group Dexmed with a median of 180 minutes interquartile range (IQR): 97.50–232.50; range (Min–Max: 30–360) min vs 90 minutes in Group Plain (IQR):45–120; range (Min–Max: 15–360) min, P = 0.001. Postoperative pain scores were comparable between both groups at different time points in 24 hours, except at 0 h rest and movement, and 3h at movement. The median highest postoperative nausea and vomiting (PONV) scores within the 24 h postoperative period did not differ significantly between the groups ( P = 0.073). Conclusion: TLIP block with dexmedetomidine as an adjuvant did not decrease cumulative fentanyl consumption as compared to TLIP block with ropivacaine alone. But the time to first request of analgesia was increased in the Group Dexmed.