Ketamine Infusions Do Not Improve Time at Goal Sedation in a Burn Intensive Care Unit

Introduction: Ketamine, administered by continuous infusion, has gained popularity as an option for sedation in critically ill adults, despite limited literature to support this practice. Ketamine is an attractive option for critically ill burn patients, as it provides both sedation and analgesia. We compared the amount of time at goal sedation while patients received ketamine vs. after ketamine was discontinued. Adjunct analgesic and sedative use were compared. We hypothesized ketamine would improve the amount of time at goal sedation and decrease the adjunct analgesics and sedatives required.


Methods: This was an observational study including patients admitted to the burn intensive care unit, receiving IV sedatives, and prescribed ketamine as part of usual care. Patients were included more than once if they received multiple courses of ketamine. Time at goal sedation, adjunctive sedative and analgesic requirements, pain scores, and psychosocial screening scores were compared for last 72 hours of the ketamine infusion vs. the 72 hours after ketamine discontinuation. Matched pairs analyses were conducted for all variables.


Results: Thirty courses of ketamine were administered to 28 patients. Median age was 39 (28, 46.75), and median TBSA was 27.75% (18.63, 46.5). 10 subjects had inhalation injury. Subjects were more often below goal RASS during ketamine use (38.4% vs 10.6%; p=.0002). During ketamine infusion, patients were at goal sedation 49.4% of the time compared to 78% of the time post-ketamine (p=0.0003). Subjects received significantly more fentanyl (2163 OME vs 583.9 OME; p< 0.001) and propofol (9444 mg vs 4389mg; p=0.0314) while receiving ketamine, but other adjunct sedative and analgesic use did not differ. Average pain scores were modestly lower during ketamine infusion (0.94 vs 1.41; p=0.0358). Of 18 subjects screened for psychological symptoms, a majority endorsed mild to moderate anxiety or depression. Suicidal ideation was rare.


Conclusions: In this observational analysis of critically ill burn patients, ketamine infusions did not improve time at goal sedation and were associated with more time below target. These findings suggest that ketamine may be insufficient to meet sedation goals in this population. Further research is needed to guide optimal sedation strategies in this population.