Ketamine sedation in mechanically ventilated patients: A systematic review and meta-analysis

Purpose: Ketamine use as a sedative agent in mechanically ventilated patients is increasing. This systematic review and meta-analysis collates existing literature and quantifies the impact of ketamine in mechanically ventilated patients. Materials and methods: EMBASE, MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, conference proceedings, and reference lists were searched. Randomized and nonrandomized studies were included, and two reviewers independently screened abstracts of identified studies for eligibility. Results: Fifteen studies (n = 892 patients) were included. Random effects meta-analytic models revealed that ketamine was associated with a reduction in propofol infusion rate (mean difference in dose, −699 μg/min; 95% CI −1169 to −230, p = .003), but had no impact on fentanyl or midazolam. Ketamine was not associated with mortality, on-target sedation, vasopressor dependence, or hospital length of stay. Cardiovascular complications (e.g. tachycardia and hypertension) were most commonly reported, followed by neurocognitive events, such as agitation and delirium. Conclusions: The data regarding ketamine use in mechanically ventilated patients is limited in terms of quantity, methodological quality, and demonstrated clinical benefit. Ketamine may play a role as a sedative-sparing agent, but may be associated with harm. High-quality studies are needed before widespread adoption of ketamine earlier in the sedation pathway.