2025 Southeastern Residency Conference

Title: Evaluation of Low-Dose Ketamine for Pain Managment in the Emergency Department: Impact on Opioid Requirements
Authors: Valery Cepeda, Emily Harman 
Objective:
Describe the use of pain-dose ketamine in the Emergency Department and impact on outpatient opioid requirements. 
Self-Assessment Question:
True or False: This study found the use of pain-dose ketamine resulted in lower MME requirements both in the ED and in outpatient prescriptions.
Background: 
Ketamine, traditionally used as a dissociative anesthetic for sedation and anesthesia, has gained attention for its off-label use in pain management. Its NMDA receptor antagonism provides effective analgesia, making it a promising alternative or adjunct to opioids, particularly when opioids are less effective or carry a high risk of adverse effects. This study aimed to evaluate whether low-dose (0.1-0.3 mg/kg IV) ketamine could reduce opioid requirements compared to opioids alone in emergency department (ED) patients. 
Methodology: 
This retrospective, observational cohort study included adult patients discharged from the ED who received either pain-dose ketamine or opioid medication for pain management or minor procedures at Northeast Georgia Medical Center between January 1, 2024 and June 30, 2024. The primary outcome was total opioid consumption in the ED, measured in morphine milligram equivalents (MMEs), in patients receiving pain-dose ketamine compared with those receiving opioids alone. Secondary outcomes included average change in pain scores during ED stay and total daily MME of opioid prescriptions issued at discharge. To control for confounding factors, patients were matched into 50 pairs based on similar demographic and clinical characteristics (age, gender, and indication for therapy), with one patient in each pair receiving only opioids (opioid-only group) and the other receiving ketamine plus/minus opioids (ketamine group). Data on demographics, medical history, dosing, adjunctive pain medications, and pain scores were collected, and statistical analyses were performed using descriptive and inferential methods, with statistical significance set at p<0.05. 
Results:  
A total of 133 patients met the inclusion criteria. One hundred patients were matched with 50 patients in the ketamine group and 50 in the opioid-only group. Baseline characteristics were similar between the two groups. For indication, 64% of the ketamine group received treatment for acute pain compared to 88% in the opioid-only group, while 36% of the ketamine group received treatment for procedural pain versus 12% in the opioid-only group. The ketamine group had a statistically significant higher total opioid consumption during the ED stay compared to the opioid-only group (median MME 17.5 [IQR 12-30] vs. median MME 12 [IQR 5-15]; p = 0.002). Change in pain score was greater in the ketamine group compared to the opioid group (median 0 [IQR 0–5] vs. median 0 [IQR 0–3.25]; p = 0.173). Additionally, the ketamine group demonstrated a statistically significant increase in daily MME requirements for outpatient opioid prescriptions (median MME  30 [IQR 25–39.5] vs. median MME 30 [IQR 20–38]; p = 0.041). 
Conclusion:  
This study found that ED patients receiving ketamine (plus/minus opioids) had higher total opioid requirements during their ED stay and required increased daily opioid doses at discharge compared to those receiving opioids alone. Pain score reductions were similar between the groups. The observed increase in MME requirements in the ketamine group may be attributable to its more frequent use for procedural sedation, as opposed to solely treating acute pain. Additional research is needed to better identify specific indications and optimal use of pain-dose ketamine in the emergency department.