Ketamine

Question 1

Indications

Answer 1

• Severe pain that has not been adequately controlled with an opiate.
• Inducing dissociation.
• Acute behavioural disturbance causing a severe to immediately life-threatening risk to safety.
• Rapid sequence intubation (RSI).
• Significant movement during CPR that is interfering with resuscitation.
• Asthma with severe agitation that is impairing the ability to safely provide treatment or transport.

Question 2

Contraindications and Cautions

Answer 2

Contraindications:
-Known severe allergy.
- Age less than one year.

Cautions:
- Altered level of consciousness. Ketamine may reduce the level of consciousness.

• Signs of shock. Ketamine may make shock worse.
• Current myocardial ischaemia. Ketamine may increase myocardial oxygen demand.
• Concurrent administration of opiates or midazolam. This will increase and prolong the effects.
• Aged greater than or equal to 75 years, particularly if frail. The effects of ketamine will be increased and prolonged in this cohort.

Question 3

Actions

Answer 3

Ketamine has complex actions,
but is predominantly an N-methyl-d-aspartate (NMDA) receptor antagonist (blocker), resulting in inhibition of excitatory neurotransmitters in the brain.

Low doses cause analgesia, larger doses cause amnesia and
dissociation, and high doses
cause anaesthesia.

Question 4

Route

Answer 4

IV, PO, IM, IO,

Question 5

Dosage

Answer 5

Analgesia: 0.25mg/kg IV, 0.5mg/kg IM/PO
Dissociation: 0.5 - 1mg/kg IV 1-2mg/kg IM
ABD: 1mg/kg IV, 5mg/kg IM
RSI: 1mg-2mg/kg.

Question 6

Side Effects

Answer 6

Common:
-transient hypertension,
- tachycardia,
- apnoea,
- nausea and vomiting,
-sedation,
- hallucinations
-effects increased with other medications