Association Between Receipt of Ketamine vs Etomidate for Emergency Tracheal Intubation and Symptoms of Posttraumatic Stress Disorder at 12 Months

Background

One of 3 patients in the ICU receiving mechanical ventilation demonstrate posttraumatic stress disorder (PTSD). A single dose of ketamine has been shown to reduce PTSD symptoms in outpatients with chronic PTSD, but its long-term effect is unknown in patients who are critically ill and mechanically ventilated.

Research Question

Is ketamine, when used for induction of anesthesia before emergency tracheal intubation, associated with fewer symptoms of PTSD at 12 months compared with etomidate?

Study Design and Methods

This was a secondary analysis of a cluster-randomized trial that examined the effect of oxygen saturation targets in patients receiving invasive mechanical ventilation in an emergency department or ICU. Symptoms of PTSD were assessed by trained neuropsychologist raters using the PTSD Checklist for Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (PCL-5) by phone. Scores ranged from 0 to 80, with higher scores indicating more severe PTSD symptoms. A score of ≥ 31 indicated probable PTSD. Symptoms of PTSD were compared between patients who received ketamine and patients who received etomidate using a proportional odds logistic regression model adjusting for age, race, sex, education, depression or PTSD before illness, comorbidities, severity of illness, sepsis, and location of intubation.

Results

Among the 141 patients included in this analysis, 52 patients (37%) received ketamine and 89 patients (63%) received etomidate. The median PCL-5 score at 12 months was 7 (interquartile range [IQR], 1-18) for patients who received ketamine and 14 (IQR, 5-27) for patients who received etomidate (reference; adjusted OR, 0.39; 95% CI, 0.20-0.76). A total of 8 patients (15.4%) who received ketamine and 18 patients (20.2%) who received etomidate met criteria for probable PTSD.

Conclusions

Compared with etomidate, induction with ketamine during emergency tracheal intubation was associated with significantly fewer symptoms of PTSD at 12 months. A randomized trial is needed to confirm this finding.