Intraoperative and postoperative infusion of dexmedetomidine combined with intravenous butorphanol patient-controlled analgesia following total hysterectomy under laparoscopy

The present prospective, randomized, double-blinded, controlled study aimed to investigate the efficacy and safety of dexmedetomidine (DEX) combined with butorphanol for patient-controlled intravenous analgesia (PCIA) following total laparoscopic hysterectomy. A total of 88 patients undergoing total laparoscopic hysterectomy and receiving postoperative PCIA were divided into two groups following surgery. Patients received DEX 0.5 µg/kg intravenously in the DEX group or 0.9% normal saline in the control (CON) group following anesthesia induction. Postoperatively, the PCIA (10 mg butorphanol with 300 µg dexmedetomidine in the DEX group or without DEX in the CON group) was delivered as a 0.5 ml bolus (lockout interval of 15 min) with a continuous background infusion of 2 ml/h. Cardiovascular and respiratory variables, cumulative butorphanol consumption, pain scores, level of sedation, concerning adverse events and the degree of patient satisfaction were recorded for 24 h post-surgery. A total of 81 patients completed the study. Blood pressure and heart rate exhibited no significant difference between the two groups during surgery and for 24 h post-surgery. Compared with the CON group, patients in the DEX group required ~19% less butorphanol (P<0.05). During the first 24 h post-surgery, patients from the DEX group had a significantly lower visual analogue scale score at rest and movement states compared with the CON group (P<0.05). There was no significant difference in sedation score between the groups. The satisfaction scores were significantly higher in the DEX group compared with those in the CON group (P<0.05). Compared with the CON group, the DEX group exhibited a lower rate of postoperative nausea and vomiting (P<0.05). There was no occurrence of serious adverse events, including respiratory depression, hypotension, bradycardia and somnolence. In conclusion, following total laparoscopic hysterectomy, the loading dose of DEX (0.5 µg/kg) followed by a continuous infusion as an adjunct to butorphanol PCIA resulted in effective analgesia, significant butorphanol sparing and less butorphanol-induced nausea and vomiting without excessive sedation or adverse effects. The trial registration number was ChiCTR1800015675 at the Chinese Clinical Trial Registry (chictr.org.cn) and the date of registration was 4th April 2018.