Comparison of dexmedetomidine vs. remifentanil combined with sevoflurane during radiofrequency ablation of hepatocellular carcinoma: a randomized controlled trial

Remifentanil is widely used for ultrasound-guided percutaneous radiofrequency ablation (RFA) of small hepatocellular carcinoma (HCC). We determined whether dexmedetomidine could be an alternative to remifentanil for RFA of HCC under general anesthesia with sevoflurane. We prospectively randomized patients scheduled to undergo RFA for HCC to a dexmedetomidine (DEX) group or remifentanil (REMI) group (47 patients each). In the DEX group, a bolus infusion (0.4 μg kg ) was started 15 min before anesthesia induction and continued at 0.2 μg kg h until 10 min before the end of surgery. In the REMI group, 3 μg kg h of remifentanil was administered from 15 min before anesthesia induction to the end of the surgery. The primary endpoint was postoperative pain intensity. Secondary endpoints included analgesic requirement, postoperative liver function, patient comfort, and hemodynamic changes. Group allocation was concealed from patients and data analysts but not from anesthesiologists. Postoperative pain intensity, analgesic consumption, comfort, liver function, and time to emergence and extubation did not differ between the two groups. Heart rate, but not mean arterial pressure, was significantly lower in the DEX group than in the REMI group, at 1 min after intubation and from 30 min after the start of the surgery until anesthesia recovery. Sevoflurane concentration and dosage were significantly lower in the DEX group than in the REMI group. During RFA for HCC, low-dose dexmedetomidine reduced the heart rate and need for inhalational anesthetics, without exacerbating postoperative discomfort or liver dysfunction. Although it did not exhibit outstanding advantages over remifentanil in terms of pain management, dexmedetomidine could be a safe alternative adjuvant for RFA under sevoflurane anesthesia. Chinese Clinical Trial Registry, ChiCTR-OPC-15006613 . Registered on 16 June 2015.