Companion Document Ketamine Clarification

The ALS PCS 5.4 Companion Document (page 10) states that “ketamine would be the preferred analgesic option for hypotensive patients or when there is a risk of hemorrhagic shock or respiratory depression.” This statement aligns with CEPCP expectations when applied within an evidence-informed, patient-specific context. It does not suggest ketamine should be used instead of fentanyl in all hypotensive cases, but rather that ketamine is preferred in select patients where the risk of opioid-related respiratory depression or hemodynamic instability is elevated.

1. Fentanyl remains the first-line analgesic in most trauma patients.
Fentanyl is an effective, fast-acting opioid that provides excellent pain relief when carefully titrated. Under ALS PCS 5.4, the recommended dosing is 25 to 75 micrograms per administration. Where possible, this should be delivered in small aliquots within a three minute timespan. Reassessment should occur between doses. The cumulative dose should not exceed 200 micrograms. When used in this manner, fentanyl has minimal hemodynamic impact and is generally safe, including in patients with borderline hypotension (Alonso-Serra & Wesley, 2003; Thomas et al., 2009). The primary concern is not hypotension, but the potential for respiratory depression, especially in patients with reduced reserve or multisystem injury.

2. Ketamine is appropriate when the risk of respiratory depression is high.
Ketamine preserves airway reflexes, maintains respiratory drive, and supports cardiovascular function. These properties make it well-suited for trauma patients with compromised physiology, including those with suspected hemorrhagic shock, altered LOC, or high risk for hypoventilation. In these scenarios, ketamine may be a more appropriate first-line agent. It is particularly valuable in patients where opioid-induced respiratory suppression could worsen perfusion or complicate airway management (Radvansky et al., 2015; Jabre et al., 2019).

3. CEPCP supports staged or combination use of fentanyl and ketamine.
CEPCP permits the sequential use of fentanyl followed by ketamine when indicated. If fentanyl is administered at a safe and effective dose (typically up to 75 mcg) but the patient continues to experience significant pain, ketamine may be introduced. This staged approach allows for robust analgesia, reduces the overall narcotic burden, and avoids the cumulative respiratory risk associated with higher opioid doses. Ketamine may also be selected as the initial analgesic when the patient’s condition suggests that fentanyl poses higher risk from the outset.

4. This approach reflects current best practices in trauma analgesia.
Multimodal and staged pain management strategies are increasingly recognized as best practice in both prehospital and in-hospital trauma care. Combining fentanyl and ketamine allows paramedics to tailor treatment to evolving patient needs while mitigating risks associated with a single-agent approach. CEPCP’s flexibility in permitting both agents supports the delivery of safer and more effective pain management (Ducharme et al., 2019).

References:

• Alonso-Serra H, Wesley K. Prehospital pharmacology. Prehospital Emergency Care. 2003;7(3):364–371.
• Thomas SH, Silvanus V, Wedel SK. Intravenous fentanyl in trauma. Prehospital Emergency Care. 2009;13(2):250–254.
• Radvansky BM, Puri S, Sifonios AN, Eloy JD, Le V. Ketamine in acute care. Pain Physician. 2015;18(5):395–400.
• Jabre P, et al. Ketamine for prehospital analgesia: a systematic review. Prehospital Emergency Care. 2019;23(4):507–518.
• Ducharme S, et al. Fentanyl and ketamine in trauma care. CJEM. 2019;21(5):628–635.