Ketamine-induced Catalepsy during Adult Sedation in the Emergency Department

Abstract

BackgroundKetamine continues to rise in popularity for procedural sedation in the Emergency Department (ED) for both adult and pediatric patients. The medication has a good safety profile and is well tolerated in the majority of patients. However, the Emergency Physician should be aware of the full range of side-effects that may be encountered, so as to best anticipate and prepare for potential complications. ObjectivesWe describe two cases of catalepsy (muscle hypertonia with dissociation) in patients undergoing sedation with ketamine. Case ReportIn the first case, a patient presented to the ED after a prehospital awake nasal intubation for an exacerbation of chronic obstructive pulmonary disease. After sedation with ketamine, he was extubated and transitioned to bi-level positive pressure ventilation. Shortly after receiving ketamine, he exhibited severe muscular hypertonia of the upper extremities with facial grimacing. A second patient underwent ketamine sedation for reduction of a shoulder dislocation. After medication administration, he exhibited full body muscular hypertonicity, interfering briefly with the procedure. In both patients, catalepsy resolved spontaneously. ConclusionsKetamine-induced catalepsy is a self-limited side-effect that has the potential to interfere with procedures performed under sedation.