Key Results

The trial enrolled 90 children, with 50 percent allocated to each group. The mean age was 12 years. Ketamine was shown to be noninferior to fentanyl for pain reduction at 30 minutes after administration of the study medication.

• Primary Outcome:
  • Ketamine: 30.6 (95% CI, −35.8 to −25.4)
  • Fentanyl: 31.9 (95% CI, −37.2 to −26.6)
  • The 95% confidence intervals did not cross the prespecified noninferiority margin of 10 mm.
• Secondary Outcomes:
  • No significant differences were observed in the highest achieved sedation scores, mean capnometry values, vital signs, or need for rescue
    analgesia.
  • Overall, more adverse events were observed in the ketamine group (49) versus the fentanyl group (14). All adverse events were minor and transient. Except for the 15-minute assessment, where the ketamine group had much more drowsiness (17 versus 4), there was no significant difference in the number of adverse events between groups at each assessment point.
  • No difference occurred in the need for additional analgesia (11 in the ketamine group and nine in the fentanyl group).

Evidence-Based Medicine Commentary

1. Blinding: They used sealed envelopes, but they did not specifically state that they were opaque envelopes. Computer randomization is considered a more secure system and less likely to be broken. To confirm blinding, they asked the staff to guess group allocation at the 30-minute assessment. Sixty-three percent of staff guessed correctly, suggesting blinding was not maintained. These two factors could have introduced bias into the study.
2. Selection Bias: The patients were not recruited consecutively but rather represented a convenient sample of patients. More than one-fifth (22 percent) of eligible patients were excluded for a variety of reasons. One reason was clinician preference. This could introduce selection bias and impact the conclusion of noninferiority.
3. Co-administration: The study design did not allow for co-administration of ibuprofen with the IN medication. Ibuprofen is an effective analgesic and is opioid-sparing. While this design allowed the researchers to answer the question about the effectiveness of the two medications in question, this is not how we would manage these patients in the real world. Often, parents have provided some analgesia (ibuprofen or acetaminophen) before arrival, or children will be given a dose in the emergency department.

Bottom Line

IN ketamine is a noninferior analgesic compared to IN fentanyl for children with acute extremity injuries but does cause more minor adverse events.

Case Resolution

You instruct the nurse to administer 1.5 mg/kg of IN ketamine to the boy while he waits for his X-ray. His pain decreases to 5/10, and the X-ray confirms a buckle fracture. You splint him, which provides even more pain relief.

Thank you to Dr. Samina Ali, a pediatric emergency physician, clinician-scientist, and professor of pediatrics and emergency medicine at the University of Alberta in Edmonton.

Remember to be skeptical of anything you learn, even if you heard it on the Skeptics’ Guide to Emergency Medicine.