Ketamine

Ketamine is a noncompetitive N-methyl-D-aspartate receptor antagonist that blocks glutamate. It has a direct action on the cortex and limbic system. It produces a cataleptic-like state wherein the patient is withdrawn from the surrounding environment. It is a general anesthetic that causes reversible loss of consciousness, allowing surgical procedures to be carried out without pain and distress.

• General anesthesia (major surgical procedures)

Adult Dose (IV):

• Induction of anesthesia: 1-4.5 mg/kg via slow IV inj over 60 sec
• 2 mg/kg produces surgical anesthesia within 30 sec lasting 5-10 min
• Maintenance: Half to full induction dose repeated OR 10-45 mcg/kg/min infusion

Adult Dose (IM):

• Induction of anesthesia: 6.5-13 mg/kg
• 10 mg/kg produces surgical anesthesia within 3-4 min lasting 12-25 min

Child Dose: No specific data; use as directed by physician

Common Side Effects:

• Rash
• Erythema (skin redness)
• Vomiting
• Nausea
• Agitation
• Nightmare
• Abnormal behavior
• Double vision
• Hallucination
• Increased respiratory rate
• High blood pressure
• Confusion
• Nystagmus
• Muscle coordination impaired
• Tonic-clonic seizures
• Tachycardia

Precautions:

• Ketamine may decrease alertness, affect vision or make you feel sleepy and dizzy; do not drive if these symptoms occur
• Inform doctor if pregnant or suffering from severe heart disease, recent stroke or serious head/brain injury
• Safe to use in breastfeeding mothers

Contraindications:

• Hypertension
• History of cerebrovascular accident
• Eye injury, raised ocular and intracranial pressure
• Psychotic disorders

Drug Interactions:

• Prolonged recovery time with barbiturates or narcotics
• May potentiate neuromuscular blocking effects of atracurium and tubocurarine
• Increased risk of bradycardia, hypotension or decreased cardiac output with halogenated anesthetics
• May potentiate CNS depression with CNS depressants
• Reduction in seizure threshold with theophylline

Food Interactions: Caution is advised when consuming alcohol with Ketamine; consult your doctor.

Use in Pregnancy: Information regarding use during pregnancy is not available; consult your doctor.

Use in Lactation: Probably safe; limited human data suggests drug does not represent significant risk to baby.

Renal Impairment: Safe in kidney disease; no dose adjustment recommended; however inform doctor if you have underlying kidney disease.

Hepatic Impairment: Caution in liver disease; dose adjustment may be needed; consult your doctor.

Overdose: Respiratory depression, hypertension, tachycardia, hallucinations; symptomatic supportive treatment; benzodiazepines may be used for seizure control.