Ketamine: Current applications in anesthesia, pain, and critical care

Summary & key facts

This 2014 review describes how ketamine, an anesthetic first sold in 1970, is used today in anesthesia, pain care, and critical care. The paper says ketamine has many effects: it can raise heart rate and blood pressure, relax airways, spare breathing, and block NMDA receptors. Newer research reported possible neuroprotective, antiinflammatory, antitumor, and prolonged antidepressant effects, and low-dose uses have expanded how clinicians apply the drug. The review also notes side effects, a history of stigma and abuse potential, and that many modern anesthesiologists get little training with ketamine.

Key facts:

• Ketamine was introduced commercially in 1970 and is described as a rapid-acting, nonbarbiturate general anesthetic.
• Ketamine raises heart rate, blood pressure, and cardiac output by stimulating the sympathetic nervous system.
• Ketamine has bronchodilator effects and minimal depression of central respiratory drive, which is why it is used for patients with active bronchospasm and in some rescue situations.
• A commonly cited dosing regimen for severe bronchospasm is a loading dose of 0.1–0.2 mg/kg IV followed by an infusion of 0.15–2.5 mg/kg per hour.
• In military and prehospital settings, reported regimens include 50–100 mg intramuscularly or 50 mg intranasally, repeated every 30–60 minutes as needed (examples used in practice, per the review).
• Ketamine’s main action is noncompetitive antagonism of the NMDA receptor; it also affects opioid, monoamine, cholinergic, purinergic and adrenergic systems.
• Ketamine is metabolized in the liver to norketamine, which is about one-third to one-fifth as potent as ketamine as an anesthetic, and is excreted in urine and feces.
• The review reports possible additional effects from research data: neuroprotective, antiinflammatory (for example, suppression of NO synthase and inhibition of TNF-α and IL-6 gene expression), antitumor activity in some laboratory models, a
• The paper notes limitations and concerns: emergence reactions (distressing perceptual changes), stigma related to veterinary and recreational use, abuse potential, and that many current anesthesiologists receive little ketamine training.

Abstract

Ketamine was introduced commercially in 1970 with the manufacturer's description as a “rapidly acting, nonbarbiturate general anesthetic” and a suggestion that it would be useful for short procedures. With the help of its old unique pharmacological ...

Topics

Anesthesia and Neurotoxicity Research Anesthesia and Pain Management Anesthesia and Sedative Agents

Categories

Anesthesiology and Pain Medicine Health Sciences Medicine

Tags

Anesthesia Anesthetic Intensive care medicine Ketamine Medicine