Low-dose short infusion ketamine as adjunct to morphine for acute long bone fracture in the emergency department: a randomized controlled trial

• Published in: BMC emergency medicine 2024-05, Vol.24 (1), p.80-80, Article 80
• Main Authors: Eddie, Elisa Audrey, Zahedi, Ahmad Zulkarnain Bin Ahmad, Jamaluddin, Sabariah Faizah Binti, Noor, Julina Md
• Format: Article
• Language: English
• Subjects: Adult; Aged; Analgesia; Analgesics; Analgesics - administration & dosage; Analgesics, Opioid - administration & dosage; Anesthesia; Care and treatment; Consent; Demographic variables; Diagnosis; Dizziness; Dosage and administration; Drug dosages; Drug Therapy, Combination; Emergency Department; Emergency medical care; Emergency medical services; Emergency Service, Hospital; Female; Fentanyl; Fractures; Fractures, Bone; Humans; Infusion; Infusion pumps; Infusions, Intravenous; Intravenous administration; Ketamine; Ketamine - administration & dosage; Long bone; Long-bone fracture; Male; Medical research; Middle Aged; Morphine; Morphine - administration & dosage; Narcotics; Nurses; Pain; Pain Management - methods; Pain Measurement; Pain perception; Patients; Pharmacists; Physicians; Side effects; Single-Blind Method; Testing; Vital signs
• ISSN: 1471-227X; 1471-227X
• DOI: 10.1186/s12873-024-00997-w

Ketamine is recognized as an alternative for pain management; however, concerns about emergent adverse reactions have limited its widespread adoption. This study aimed to assess the efficacy of a short infusion of low-dose ketamine (LDK) compared to intravenous morphine (MOR) as adjunctive analgesia for acute long bone fracture pain. This single-blinded, randomized controlled trial was conducted in a single emergency department. Patients with acute long bone fractures and numerical rating scale (NRS) pain scores ≥ 6 following an initial dose of intravenous morphine were assigned to receive either a LDK (0.3 mg/kg) over 15 min or intravenous MOR at a dose of 0.1 mg/kg administered over 5 min. Throughout a 120-min observation period, patients were regularly evaluated for pain level (0-10), side effects, and the need for additional rescue analgesia. A total of 58 subjects participated, with 27 in the MOR group and 31 in the LDK group. Demographic variables and baseline NRS scores were comparable between the MOR (8.3 ± 1.3) and LDK (8.9 ± 1.2) groups. At 30 min, the LDK group showed a significantly greater mean reduction in NRS scores (3.1 ± 2.03) compared to the MOR group (1.8 ± 1.59) (p = 0.009). Similarly, at 60 min, there were significant differences in mean NRS score reductions (LDK 3.5 ± 2.17; MOR mean reduction = 2.4, ± 1.84) with a p-value of 0.04. No significant differences were observed at other time intervals. The incidence of dizziness was higher in the LDK group at 19.4% (p = 0.026). Short infusion low-dose ketamine, as an adjunct to morphine, is effective in reducing pain during the initial 30 to 60 min and demonstrated comparability to intravenous morphine alone in reducing pain over the subsequent 60 min for acute long bone fractures. However, it was associated with a higher incidence of dizziness. NMRR17318438970 (2 May 2018; www.nmrr.gov.my ).