In this episode, I’ll discuss a meta-analysis of controlled trials evaluating induction agents for tracheal intubation of critically ill patients.
When critically ill patients require an induction agent to tolerate tracheal intubation, clinicians must balance induction-agent effectiveness with potential adverse effects. Clinical endpoints of the various studies of induction agents are heterogeneous, and there is a lack of consensus as to which agent is the best in a given scenario. In an effort to bring clarity to this topic, a group of authors conducted a systematic review and network meta-analysis of randomized controlled trials looking at induction agents for tracheal intubation of critically ill patients.
21 randomized controlled trials comparing at least 2 induction agents in over 6000 critically ill patients undergoing endotracheal intubation were analyzed. Outcomes of interest were hemodynamic instability during intubation, hypoxemia, cardiac arrest, mortality, intensive care unit and hospital length of stay, vasopressor use, adrenal insufficiency, and first-pass success.
Compared with etomidate, ketamine had a relative risk of 1.31 for hemodynamic instability during intubation. Ketamine+propofol however had lower risks of hemodynamic instability during intubation compared to etomidate or ketamine with a relative risk of 0.44 and 0.34, respectively. Compared with etomidate, ketamine may decrease the need for the initiation of post-intubation continuous infusion vasopressors however the 95% confidence interval for the relative risk crossed 1, making this of low certainty. As expected, etomidate caused increased adrenal suppression compared with other agents.
The authors concluded:
When considering sedation agents for endotracheal intubation of the critically ill, etomidate probably causes less hemodynamic instability during intubation when compared with ketamine. However, etomidate may increase the need for the initiation of post-intubation continuous infusion vasopressors when compared with ketamine and increases adrenal suppression. The clinical importance of these competing effects remains uncertain. Ketamine-propofol may decrease hemodynamic instability during intubation when compared with etomidate and ketamine though the available evidence is too limited and uncertain to support firm conclusions and further randomized trials are needed.
The most interesting finding in my opinion was that ketamine, although often selected for its supposed lack of hypotensive effect, had a greater risk of hemodynamic instability. Only when ketamine was combined with propofol did the rate of hemodynamic instability decrease. Unfortunately, since these results with ketamine+propofol had low certainty, they are more hypothesis-generating than they are able to inform routine practice.
The article in this episode is a selection from my Hospital Pharmacy Academy’s weekly literature digest. Have you ever felt like your physician colleagues are one step ahead of you with new literature developments? Every week, Academy members are provided a summary curated and explained by me of the top hospital pharmacy-related articles published that week from over 20 major journals and sources to save you time and keep you up to date with the literature. To get immediate access, go to pharmacyjoe.com/academy.
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