The Case

An 8-year-old boy presents to the emergency department with a painful wrist injury after falling at the playground. His parents gave him an appropriate dose of ibuprofen before arriving at the emergency department. His pain is a 7/10, and the triage nurse asks you for some additional medication for his pain while he is waiting for his X-ray.

Background

Children represent a group of patients who aren’t likely to receive adequate analgesia.1,2 This phenomenon is known as oligoanalgesia, or poor pain management through the underuse of analgesics. Despite three decades of research in this area, recent evidence confirms that ED pain management in children is still suboptimal.

A retrospective cohort study of children presenting to the emergency department with an isolated long-bone fracture showed almost one-third received inadequate medication, and 59 percent received no pain medications during the critical first hour of assessment.3 Other studies have demonstrated that only 35 percent of children presenting to a pediatric emergency department with fractures or severe sprains receive any analgesics.4,5 Two potential options for providing faster-acting, effective, and easy-to-administer pain medications to children are intranasal (IN) fentanyl and ketamine.

IN fentanyl is an excellent alternative to oral or IV opioids when rapid pain management is desired or IV placement is not otherwise necessary. Fentanyl at doses of 1.5–2 mcg/kg (maximum 100 mcg) provides effective and rapid analgesia comparable to that of IV morphine.

Ketamine is a noncompetitive N-methyl-D-aspartate (NMDA) and glutamate receptor antagonist that provides analgesia by virtue of decreasing central sensitization “wind-up” phenomenon (“a progressive increase in the number of action potentials elicited per stimulus that occurs in dorsal horn neurons”⁶) and pain memory. Sub-dissociative ketamine has been used in the adult population as an effective opioid-sparing alternative that is associated with higher rates of minor but generally well-tolerated adverse effects.

The sub-dissociative ketamine dose for children is 0.5–1 mg/kg. It can provide rapid pain management for children who lack vascular access with the added benefit of lasting longer (60 minutes) compared to IN fentanyl (30 minutes).

Clinical Question

In children with acute extremity injuries, is IN ketamine noninferior to IN fentanyl for pain management?

Reference

1. Frey TM, Florin TA, Caruso M, et al. Effect of intranasal ketamine vs fentanyl on pain reduction for extremity injuries in children: the PRIME randomized clinical trial. JAMA Pediatr. 2019;173(2):140-146.

• Population: Children ages 8 to 17 years presenting to the emergency department with moderate to severe pain due to traumatic limb injuries (visual analogue scale >35 mm).
  • Exclusions: Significant head, chest, abdomen, or spine injury; Glasgow Coma Scale <15 or inability to report a visual analogue scale score; nasal trauma or aberrant nasal anatomy; active epistaxis; ketamine or fentanyl allergy; history of psychosis; opioid administration prior to arrival; non-English speaking; in police custody; and postmenarchal girls without a negative pregnancy test.
• Intervention: IN ketamine 1.5 mg/kg (max 100 mg)
• Comparison: IN fentanyl 2 mcg/kg (max 100 mcg)
• Outcomes:
  • Primary Outcome: Pain reduction after 30 minutes.
  • Secondary Outcomes: Sedation level, capnometry values, adverse events, the need for rescue analgesia, and change in vital signs.

Authors’ Conclusions

“Ketamine provides effective analgesia that is noninferior to fentanyl, although participants who received ketamine had an increase in adverse events that were minor and transient. Intranasal ketamine may be an appropriate alternative to intranasal fentanyl for pain associated with acute extremity injuries. Ketamine should be considered for pediatric pain management in the emergency setting, especially when opioids are associated with increased risk.”