Perineural dexmedetomidine added to ropivacaine for ultrasound-guided erector spinae plane block prolongs analgesia duration and reduces postoperative opioid consumption after thoracotomy: a prospective, randomized study

Abstract Background: Single-injection erector spinae plane block (ESPB) has been reported to be successfully used for analgesia after open thoracotomy. However, the duration of analgesia is not long enough. Adding dexmedetomidine to local anesthetics is frequently used to prolong the duration of single-injection regional nerve block. This randomized study was designed to assess whether adding dexmedetomidine to ropivacaine for ESPB could effectively prolong the duration of analgesia and reduce opioid consumption after open thoracotomy.Methods: Sixty patients with esophageal cancer were randomized to receive ESPB using 28 mL of 0.5% ropivacaine, with 2 mL of normal saline (group R) or 0.5 µg/kg dexmedetomidine in 2 mL (group RD) administered perineurally. ESPB was performed at the 5th thoracic level under ultrasound guidance. The primary outcome was the duration of analgesia. The secondary outcomes were total postoperative sufentanil consumption, numerical rating scale pain scores, Ramsay sedation scale scores and adverse effects.Results: The duration of analgesia in group RD (505.1±113.9) was longer than that in group R (323.2±75.4) (p<0.001). The total postoperative sufentanil consumption was lower in group RD (23.3±10.0) than in group R (33.8±13.8) (p=0.001). There was no significant difference in the incidence of adverse effects between the two groups.Conclusion: Adding perineural dexmedetomidine to ropivacaine for ESPB seems to be an attractive method for prolonging analgesia with almost no adverse effects in patients with esophageal cancer undergoing curative-intent thoracotomy. Trial registration: ChiCTR1800016583. Registered 10 June 2018, http://www.chictr.org.cn.