Ketamine Use for Sedation in Critically Ill Patients with Coronavirus Disease 2019 (COVID-19) Infection: A Case Series

Abstract

Introduction: Ketamine has been previously used as an add-on analgesic and a sedative agents for the treatment of critically ill surgical patients, resulting in a reduced opioid consumption. During the Coronavirus Disease 2019 (COVID-19) pandemic, a surge of critically ill patients with Acute Respiratory Distress Syndrome (ARDS) requiring mechanical ventilation with deep sedation and paralysis lead to the overuse of first line sedative medications like benzodiazepines and Propofol, exposing them to serious shortages, especially in view of worsening national economic crisis. This dilemma pushed the critical care teams to explore new medications for sedation, resulting in shifting away from the first line therapies to the use of other sedatives, like Ketamine. We describe our experience using Ketamineto maintain an adequate sedation when Midazolam was not available and Propofol contraindicated. Methods: Ketamine was used on four critically ill patients with severe COVID-19 ARDS requiring paralysis. We focused on vital signs variation and quality of sedation during Ketamine use in comparison to Midazolam/Propofol. During the transition period from Midazolam/Propofol to Ketamine, our patients had an acute increase in blood pressure, respiratory rate and heart rate, a drop in their oxygen saturation with ventilator dyssynchrony. Other deteriorations witnessed included new respiratory acidosis and cardiac arrhythmia. Discussion: In comparison to previous successful uses of Ketamine in the Intensive Care Unit ICU, its limited efficacy in our population could be explained by the requirement for neuro-muscular blockade, the high ventilatory drive and the fact that it was used alone. Conclusion: Our experience with Ketamine during drug shortage of first-line sedatives in critically ill patients with COVID-19 ARDS was shown to be insufficient when used alone as an alternative sedative agent compared to Propofol and Midazolam. Further studies with larger sample size are advised before drawing a final conclusion.