Continuous Infusion of Ketamine for Adjunctive Analgosedation in Mechanically Ventilated Patients with Chronic Obstructive Pulmonary Disease

: BACKGROUND AND AIM: Ketamine is a fast-acting, hypnotic, amnestic agent that may be used to manage pain and agitation which is refractory to commonly used sedatives and analgesics. However, there is a paucity of literature describing the effects of continuous infusion of ketamine on sedative and analgesic consumption and delirium in mechanically ventilated patients. This investigation describes a single institution’s use of ketamine infusions as a part of a sedation protocol in the respiratory intensive care unit (RICU). METHODS: This was a retrospective cohort study of mechanically ventilated patients with chronic obstructive pulmonary disease (COPD) who received ketamine infusions as a part of a sedation protocol in a 16-bed RICU. The patients have assessed sedative consumption, analgesic consumption, and delirium incidence. RESULTS: A total of 100 COPD patients receiving ketamine continuous infusion as a part of a sedation protocol between November 2017 and April 2020 were eligible and enrolled in this study. We found that patients had a reduction in opioid and benzodiazepine requirements at 24, 48, and 72 h after ketamine initiation (p<0.05). In addition, significant reductions in vasopressor requirements were observed at 24, 48, and 72 h after ketamine initiation (p<0.05). During the analyzed time frame, all patients received ketamine infusion at 4 μg/kg/min. There were no reported adverse drug reactions. CONCLUSIONS: In this cohort of COPD patients who required mechanical ventilation we found decreased benzodiazepine, opiate, and vasopressor doses when the addition of a ketamine infusion, with no adverse drug reactions. Further prospective research is warranted to define optimal dosing strategies.