What is the treatment for ketamine (Ketamine hydrochloride) emergence reaction?

From the Guidelines

Ketamine emergence reactions can be effectively managed with benzodiazepines, particularly midazolam, which has been shown to minimize this reaction when used in combination with ketamine 1. When considering the management of ketamine emergence reactions, it is essential to prioritize strategies that minimize the risk of these reactions and effectively treat them when they occur.

• The use of midazolam in combination with ketamine has been reported to reduce the incidence of emergence reactions 1.
• Prevention is crucial, and administering midazolam before ketamine induction can help minimize the risk of emergence reactions.
• Maintaining a quiet recovery environment with minimal stimulation, reassuring the patient, and providing clear orientation during emergence are also essential preventive strategies.
• Patients with psychiatric disorders, females, and those receiving higher ketamine doses are at increased risk of emergence reactions.
• These reactions typically manifest as hallucinations, vivid dreams, confusion, or agitation during recovery from anesthesia, and occur in 10-30% of patients receiving ketamine 1.
• While most reactions are self-limiting and resolve within 1-2 hours, prompt treatment with benzodiazepines, such as midazolam 1-2 mg IV, improves patient comfort and prevents potential self-injury during episodes of agitation.
• The mechanism of ketamine emergence reactions is thought to be related to its action as an NMDA receptor antagonist, causing dissociative effects and disrupting normal sensory processing 1.

From the FDA Drug Label

5.2 Emergence Reactions Emergence delirium (postoperative confusional states or agitation) has occurred in approximately 12% of patients during the recovery period, and the duration is generally a few hours. The neuropsychological manifestations vary in severity between pleasant dream-like states, vivid imagery, hallucinations, and emergence delirium In some cases, these states have been accompanied by confusion, excitement, and irrational behavior, which have been recalled as unpleasant experiences. No residual psychological effects are known to have resulted from use of ketamine hydrochloride during induction and maintenance of anesthesia. Intramuscular administration results in a lower incidence of emergence reactions The incidence of psychological manifestations during emergence, particularly dream-like observations and emergence delirium, may be reduced by using lower recommended dosages of ketamine hydrochloride in conjunction with an intravenous benzodiazepine during induction and maintenance of anesthesia [see Dosage and Administration (2.3)]. Also, these reactions may be reduced if verbal, tactile, and visual stimulation of the patient is minimized during the recovery period.

Ketamine Emergence Reaction occurs in approximately 12% of patients, characterized by emergence delirium, confusion, excitement, and irrational behavior.

• The reaction can be reduced by:
  • Using lower recommended dosages of ketamine hydrochloride
  • Administering an intravenous benzodiazepine during induction and maintenance of anesthesia
  • Minimizing verbal, tactile, and visual stimulation of the patient during the recovery period
  • Using intramuscular administration, which results in a lower incidence of emergence reactions 2 2 2

From the Research

Ketamine Emergence Reaction

• Ketamine emergence reaction is a phenomenon where patients experience behavioral disturbances and unpleasant reactions after receiving ketamine, a medication commonly used for sedation and pain control 3.
• Studies have shown that the frequency of these reactions is often exaggerated, and that ketamine can be safely used in various settings, including prehospital and emergency department environments 3, 4, 5.

Prevention and Management of Emergence Reactions

• Some studies suggest that premedication with midazolam or haloperidol can help reduce the incidence of ketamine-induced recovery agitation 6, 7.
• However, other studies argue that the use of benzodiazepines, such as midazolam, may not be necessary and can even cause significant morbidity and potential mortality 3.
• In some cases, the treatment for ketamine-induced agitation is more ketamine, rather than the addition of a benzodiazepine 3.

Comparison of Ketamine with Other Sedatives

• Ketamine has been compared to other sedatives, such as midazolam and haloperidol, in terms of its effectiveness in controlling agitation and sedation 4, 7, 5.
• Studies have shown that ketamine can provide faster sedation and agitation control compared to other medications, with similar rates of adverse events and redosing 4, 5.
• The combination of haloperidol and ketamine has been shown to be effective in controlling agitation in delirious patients, with fewer adverse events and less need for physical restraint compared to haloperidol and midazolam 7.