For 45 patients pre- and postadministration median pulse rates did not change.

Limitations of the study include its small sample size and the inability to determine whether ultimate sedation resulted from ketamine, delayed response to initial sedation, or both.

“Essentially larger studies across more hospitals are needed,” Dr. Isbister told Reuters Health. “You need large numbers to confirm that less-common adverse effects don’t occur.”

Nevertheless, the two hospitals are using ketamine. “Yes, it continues to be used in both hospitals, and it is now recommended on our state guidelines,” Dr. Isbister said.

Dr. Steven Green, of Loma Linda University Medical Center in California, and Dr. Gary Andolfatto, of Lions Gate Hospital, North Vancouver, British Columbia, Canada, wrote an accompanying editorial titled “Let’s ‘Take ‘Em Down’ With a Ketamine Blow Dart.”

“Ketamine intramuscularly is highly effective for the rapid control of agitated and violent patients and, although not devoid of risks, may represent the best option when there is truly an imminent threat to patient and caregiver safety,” they wrote. “In this circumstance, ketamine appears much more likely to get you out of trouble than to cause trouble. Bring on the blow darts!”

The National Health and Medical Research Research Council partially supported this research. The authors reported no disclosures.