High and Low Dose Ketamine in Post-Traumatic Stress Disorder

Author(s): Joey Day and Devendra K. Agrawal

Ketamine has unique properties making it a desirable drug to induce general anesthesia during surgery. However, it is typically reserved for children and adolescent patients due to its side effects in adults, including vivid dreams, hallucinations, and confusional states that may be pleasant or distressing. These symptoms may affect patients with post-traumatic stress disorder (PTSD). PTSD is a trauma-related psychological disorder that is mainly characterized by intrusive thoughts, hypervigilance, and reexperiencing of the trauma event. Most of current research focuses on the use of sub-anesthetic doses of ketamine as a treatment for PTSD. Limited information is known about high-dose ketamine use during general anesthesia and the impact this has on patients who suffer from PTSD. A literature review investigating the effects of anesthetic doses of ketamine on PTSD was conducted for this article. Findings suggest that ketamine has dose-related effects on the severity of PTSD. Specifically, low-dose ketamine has the potential as a therapeutic agent in the treatment of PTSD, while high-dose ketamine may cause worsening of PTSD symptoms. This could occur through the increase in psychomimetic symptoms, decrease in plasticity and metaplasticity, and modulation of fear memory systems experienced with anesthetic doses of ketamine. Currently, there are no published research articles directly measuring the effects of high-dose ketamine on PTSD. Further investigation is warranted to understand if anesthetic doses of ketamine worsen PTSD symptoms. This is important because it can help guide the management approach of an anesthesiologist to safely providing anesthesia to PTSD patients.