Selected Topics: Toxicology
Ketamine abusers presenting to the Emergency Department: A case series

https://doi.org/10.1016/S0736-4679(00)00162-1Get rights and content

Abstract

Ketamine hydrochloride, familiar to emergency physicians as a dissociative anesthetic, has been abused as a hallucinogen for almost 30 years. The drug produces effects similar to those of phencyclidine but with a much shorter duration of effect. Since 1996, an increasing number of patients have presented to Connecticut Emergency Departments (EDs) after the intentional abuse of ketamine. Because the medical literature contains almost no information on the consequences of ketamine abuse, we have compiled a series of ketamine abusers presenting to the ED. Among the 20 patients in this series, common presenting complaints included anxiety, chest pain, and palpitations. Tachycardia was the most common physical examination finding. Nystagmus, a common finding after phencyclidine use, was seen in only three cases. The most frequent complications after ketamine abuse were severe agitation and rhabdomyolysis. The symptoms of ketamine intoxication appear to be short-lived, with 18 of the 20 patients discharged from the ED within 5 h of presentation. Emergency physicians should include ketamine in the differential diagnosis of drug- or toxin-induced hallucinations. Methods for detecting this drug in biologic fluids are reviewed as are treatment recommendations for managing the patient who presents to the ED after abusing ketamine.

Introduction

Ketamine hydrochloride was introduced as a general anesthetic in the late 1960s as an analogue of phencyclidine (PCP), which had proved to be too toxic for human use (1). Ketamine was initially well received because it produced excellent anesthesia without the respiratory and cardiovascular depression that occurs with other agents (2). Unfortunately, a frequent complication of ketamine anesthesia use was the occurrence of disturbing hallucinations upon awakening (“emergence reactions”) (3). This limited the drug’s clinical usefulness, and by the early 1970s, it had been replaced by other anesthetics (2). Today, ketamine is used primarily to induce dissociative sedation for brief procedures that require the patient (usually a child) to be absolutely still (4). It is used in a similar manner by veterinarians (5).

Reports of ketamine abuse began to appear in the medical literature soon after its introduction into clinical practice 6, 7. The drug produces effects similar to those of PCP but with a much shorter duration of action (3). Early reports of ketamine abuse involved people who had easy access to the drug, such as health care workers and animal trainers 6, 7. In 1996, the Connecticut Poison Control Center began receiving an increasing number of calls from emergency physicians seeking treatment advice for patients who presented to the emergency department (ED) after ketamine abuse. A literature search by the authors found almost no published data on the complications of ketamine abuse.

The objective of this study was to prospectively collect data on patients presenting to Connecticut EDs after having abused ketamine. Based on our observations, we make recommendations for anticipating and treating the complications of ketamine abuse.

Section snippets

Materials and methods

This was a prospective observational case series of ketamine abusers presenting to Connecticut EDs in 1997. When the Connecticut Poison Control Center was notified of such a patient, one of the authors contacted the treating physician to obtain more information (described below). Patients were included in this case series only if the treating physician was available to review the ED visit and if all the information outlined below was available.

Demographic data included patient age and sex.

Results

During 1997, 27 cases of self-reported ketamine abuse were called in to our poison control center from Connecticut EDs. Twenty of the 27 (74%) met criteria for inclusion in the study. Two were excluded because the treating physician was unavailable, and in five other cases, information on the patient was incomplete. The 20 patients who made up our study population consisted of 11 men and 9 women, ages 15–40 years old. Almost all the subjects were Caucasian and lived in either suburban or rural

Discussion

Ketamine is a structural analogue of phencyclidine (1). Like PCP, ketamine combines analgesic and anesthetic effects without respiratory or cardiovascular depression (1). In the dissociative state induced by these drugs, the patient appears awake but is unaware of all sensory input (8). Whereas the signs and symptoms of PCP intoxication can remain for many hours, complete recovery is usually seen within 1 h after ketamine administration (3). Much like other short-acting, lipid-soluble

References (16)

There are more references available in the full text version of this article.

Cited by (167)

  • Ketamine in DUID cases in the greater Cologne area

    2024, Forensic Science International
  • Substance abuse in pregnancy

    2021, Clinical Pharmacology During Pregnancy
  • Arylcyclohexamines

    2021, Novel Psychoactive Substances: Classification, Pharmacology and Toxicology
  • Ketamine—a review of published cases

    2020, Toxicology Cases for the Clinical and Forensic Laboratory
View all citing articles on Scopus
View full text