Ketamine

Provider Level

RN/Paramedic

Class

Dissociative anesthetic, analgesic

Mechanism of Action

Non-competitive NMDA receptor antagonist that blocks glutamate. Produces a dissociative state characterized by profound analgesia, amnesia, and catalepsy while typically maintaining airway reflexes and spontaneous respirations. Causes sympathetic stimulation leading to increased heart rate and blood pressure.

Indications

Severe acute pain, procedural sedation, induction agent for rapid sequence intubation (RSI) or delayed sequence intubation (DSI), severe agitation or excited delirium.

Contraindications

Known hypersensitivity, conditions where a significant elevation in blood pressure would be hazardous (e.g. severe cardiovascular disease, known aortic aneurysm), penetrating eye injuries.

Routes

IM, IV, IO

Onset / Duration

Onset: IV/IO within 30 to 60 seconds; IM within 3 to 4 minutes. Duration: IV/IO 10 to 15 minutes; IM 12 to 25 minutes.

Adverse Effects

Emergence reactions (hallucinations, delirium), hypertension, tachycardia, hypersalivation, nausea, vomiting, transient apnea or respiratory depression (especially with rapid IV push), rare laryngospasm.

Precautions & Interactions

Push IV slowly over 1 to 2 minutes to reduce the risk of respiratory depression and apnea. Use caution in patients with psychiatric history, known elevated intracranial pressure, or ischemic heart disease.

Special Considerations

Requires continuous monitoring of cardiac rhythm, pulse oximetry, and end-tidal CO2 (capnography). Have suction readily available due to the potential for hypersalivation and vomiting. Prepare for advanced airway management if laryngospasm or apnea occurs.