The Analgesic Efficacy and Safety of Intramuscular Hydromorphone versus Butorphanol for Acute Pain in the Emergency Department：A Randomized Trial

Acute pain is a distressing encounter for most patients visiting the emergency department (ED), which severely affects their quality of life. Early analgesia is considered reasonable and necessary. However, the choice of analgesic drugs for acute pain still remains controversial. The aim of this study was to evaluate and compare the analgesic efficacy and safety of intramuscular hydromorphone and butorphanol in patients with acute pain in the ED. This randomized controlled clinical trial randomly divided 199 patients with moderate to severe acute pain into two groups in a 1:1 ratio, receiving intramuscular injections of 1 mg of hydromorphone and butorphanol, respectively. We compared the changes in pain intensity, as assessed by the Numerical Rating Scale (NRS), the requirement for supplemental analgesics, alterations in vital signs, incidence of adverse reactions, and the final destination of the patients in the two groups after the use of analgesic drugs. The results showed that, compared with the butorphanol group, the hydromorphone group showed more significant changes in NRS after administration, with higher pain relief rates at 1 h and 2 h, and a greater proportion of apparent relief at 2 h, especially in cases of severe pain ( P  < 0.05). Additionally, we observed a significant difference in the requirement for supplemental analgesics between the two groups 2 h after analgesia (0.0% vs 6.1%, P  < 0.05). There was no significant difference in the incidence of adverse reactions, the final destination of the patients, and the effects on heart rate, respiration, and oxygen saturation between the two groups ( P  > 0.05). Common adverse reactions included dizziness or headache, nausea or vomiting, and injection pain, with one case of hypotension in the hydromorphone group. Our findings showed that both hydromorphone and butorphanol could effectively alleviate moderate to severe acute pain in the ED, and that the incidence of adverse reactions was similar. Notably, hydromorphone demonstrates superior analgesic efficacy compared to butorphanol, especially in patients with severe pain. This study has been registered in the Chinese Clinical Trial Registry (Registration Number: ChiCTR2400088376, Date: 2024-08-16, retrospectively registered)