Etomidate vs. Ketamine for RSI

We use the drug Etomidate all the time as a sedative prior to paralyzing patients for intubation. As part of our Rapid Sequence Intubation kit, it is a great little drug. Works fast, has proven very safe and the effects don't last long. We also use it for moderate sedations procedures. It is a forgiving and easy drug to use.

When I first started doing moderate sedations on kiddos at a different hospital, I often used a different drug -- Ketamine. It can be given IM or IV and works great for pediatric sedations. That said, it sometimes has side effects that can make it a little less fun for patients and parents when the sedation is over. When coming out of Ketamine sedations -- especially when the drug is given IM or higher IV doses -- it can produce hallucinations and recovery agitation. Sometimes these hallucinations are disturbing -- and can be particularly so for a parent watching and holding little Johnny while he goes through this bad trip.

So why are some researchers proposing that we drop Etomidate in favor of Ketamine?

As presented at the 21st Annual Northwest States Trauma Conference, Etomidate appears to have an effect on cortisol levels that can linger long after the rapid, single bolus used for induction. This adrenal suppression that results from Etomidate has been known about for some time. Researchers wanted to know if the single bolus used for RSI could do the same. When a Harborview Medical Center study compared Etomidate RSI with a benzo/narcotic combination -- "patients given Etomidate had a nearly fourfold greater risk of respiratory failure and an average of three more days of mechanical ventilation."

Another study -- published in the Lancet -- compared Etomidate and Ketamine. By studying two groups in a randomized trial - one using Ketamine for induction and the other use Etomidate, a study found that adrenal function was significantly lower when Etomidate was used for RSI (86% vs 48 %). However, there was no significant change in mortality (35% for Etomidate vs 31% for Ketamine) or clinical outcome for trauma patients.  Given these results, the researchers concluded that "Ketamine is a safe and valuable alternative to etomidate for critically ill patients, particularly for septic patients."

So are we going to start seeing a switch to Ketamine for RSI?

OHSU Professor of Surgery Richard Mullins picked this study as one of his Trauma Top Ten at the Northwest States Trauma Conference, but expressed some doubts given that there was no significant change in outcome.

"The reality is, hundreds or thousands of people have been intubated using Etomidate over the years and we don't have hundreds of thousands of dead bodies," Mullins said.