The Impact of Adjunctive Ketamine on Sedation Requirements in Ventilated Patients with Covid-19

ABSTRACT

INTRODUCTION: Patients infected with the SARS-CoV-2 virus (COVID-19) may develop acute respiratory distress syndrome, requiring mechanical ventilation. Reports suggest that these patients may have increased sedation requirements due to intensive mechanical ventilation needs, necessitating the evaluation of additional sedation, with limited guidance available. Due to multiple drug shortages, ketamine became an attractive adjunctive option to meet sedation goals. The primary objective of this study was to compare sedation and analgesic requirements in mechanically ventilated patients with COVID-19 who received continuous ketamine infusions with those who did not. METHOD(S) A multi-center, retrospective cohort study was performed in adult patients with COVID-19 who were mechanically ventilated for at least 24 hours. Groups were allocated based on whether or not adjunctive continuous infusion ketamine was used. The primary outcome was a comparison of the sedation and analgesic agents and the median morphine equivalents (ME) required. Secondary outcomes included intensive care unit (ICU) and hospital length of stay (LOS), duration of mechanical ventilation, and in-hospital mortality. RESULT(S) A total of 1,757 patients were screened for inclusion. After exclusions, 40 patients in each group were included for analysis. More patients in the ketamine group received intravenous opiates (100% vs 80%, p < 0.01) and also had higher ME than the non-ketamine group (357 [276-440] vs 222 [141-294] mg ME daily, p < 0.01). There was also a greater LOS in the ketamine group in both the hospital (24 vs 16.5 days, p=0.01) and ICU (18.8 [12.6- 27.9] vs 14.9 [7.1-18.7] days, p=0.04). The ketamine group also experienced longer intubation durations (14.5 [9.0-23.5] vs 8.0 [4.0-13.5] days, p=0.01). There were no significant differences in in-hospital mortality or average doses of propofol, midazolam, dexmedetomidine, or vasopressors between groups. CONCLUSION(S) Ketamine use was not associated with a decrease in opioid or sedation use in patients with COVID-19 who were mechanically ventilated. Additional studies are needed to assess the role of ketamine and its impact on sedation and analgesia requirements in COVID-19 positive patients.