Ketamine not inferior to opiate-based sedation for ICU-admitted patients

Ketamine analgosedation demonstrates a similar percentage of time within target sedation range (RASS -1 to +1) when compared with opiate-based sedation, according to a study. However, the result falls short of significance for noninferiority due to lack of statistical power.

This retrospective cohort study included 169 mechanically ventilated patients admitted to the medical ICU at an academic medical centre. The research team examined the efficacy of ketamine versus opiate-based analgosedation by comparing the percentage of time within target sedation range (primary outcome) within the first 72 hours of initiation.

Secondary outcomes were as follows: percentage of time under-sedated, over-sedated, and in coma; use of concomitant analgesic, sedative, and antipsychotic agents; presence of delirium; percentage of Critical Care Pain Observation Tool (CPOT) scores at goal; and haemodynamic effects.

The mean percentage of time at RASS goal after weighting was 43.0 percent for ketamine patients versus 41.4 percent for opiate-based sedation patients. Ketamine did not appear to be significantly noninferior to opiate-based sedation (p=0.11) and demonstrated a higher median percentage of CPOT scores at goal (13.3 percent; p=0.042).

In addition, ketamine recipients received significantly less additional sedative agents than those in the opiate-based sedation group.

“This study found a higher percentage of CPOT scores within goal with less additional sedative agents required compared to an opiate-based sedation regimen,” the researchers said.