Ketamine

Question 1

Ketamine

Presentation

Answer 1

Oral administration:
25mg sublingual wafer
Intravenous/intraosseous administration:
200mg in 2mL
.

Question 2

Ketamine

Use

Answer 2

• IV: Second line agent for severe pain of traumatic origin post IV Fentanyl administration. ASMA consult needed if IV Fentanyl minimum dose (age dependent as per CPG) has not been given prior to IV Ketamine administration.
• IM: First line agent for severe pain of traumatic origin should other means of administering pain medication not be available
• Oral wafer: Second line agent for moderate to severe, acute onset pain in patients >12 years where first line agents have failed to provide adequate relief
• Actively disturbed patients requiring sedation where midazolam has already been utilised
• Combative Traumatic Brain Injury
.

Question 3

Ketamine

Type

Answer 3

• Rapid acting dissociative anaesthetic.

Question 4

Ketamine

Dose

Answer 4

Analgesia
Adult:
• IM:
o Initial does: 1 mg/kg;
o Subsequent doses at 5 minute intervals – 0.5mg/kg;
o Concentration: 200mg/2ml = 100mg/ml
• IV/IO:
o Initial dose: 10-20mg (1-2ml)
o Subsequent doses at 5 minute intervals – 10mg (1ml)
o Dilution: 200mg/2ml added to 18ml NaCl 0.9% = 10mg/ml
• Oral Wafer:
o Initial dose: 2x 25mg wafers (50mg total)
o Subsequent doses at 5 minute intervals: 1x 25mg wafer
o Administer up to 3x subsequent doses (max total administration: 125mg)
o Contact CSPSOC if additional analgesia required
Paediatric:
• IM:
o Initial does: 1 mg/kg;
o Subsequent doses at 5 minute intervals – 0.5mg/kg;
o Concentration: 200mg/2ml = 100mg/ml
• IV/IO:
o 0.1mg/kg administered slowly titrated to effect
o Repeated at 5 minute intervals as required
Sedation
IM:
• Initial dose: 2mg/kg to a max of 200mg
• IV access obtained as soon as possible
IV/IO:
• 0.5mg/kg repeated every 5 minutes until required level of sedation achieved
.

Question 5

Ketamine

Actions

Answer 5

• IM onset: 5-10 minutes
• IV onset: 1 minute
.

Question 6

Ketamine

Contraindications

Answer 6

• Hypersensitivity
• Active cardiovascular disease including cardiac chest pain, heart failure, severe or poorly controlled hypertension
• Active psychiatric condition (unless pre- treatment with midazolam)
• IM/IV/IO: Non traumatic pain
• IM/IV/IO: Age <12 months
• Oral wafer: Age <12 years
.

Question 7

Ketamine

Adverse effects

Answer 7

• Blood pressure and pulse frequently elevated
• Random purposeless movements, muscle twitching and rash are common
• Hypersalivation
• Emergence reactions (10%)
• Transient laryngospasm
• Transient apnoea or respiratory depression
.

Question 8

Ketamine

Precautions

Answer 8

• Used with caution in patients with stable psychiatric disorders such as Schizophrenia (unless pre-treatment with midazolam)
• Use with caution in patients with hyperthyroidism or receiving thyroid replacement due to increased risk of hypertension and tachycardia.
• IV Fentanyl minimum dose (age dependant as per CPG) should be given prior to IV Ketamine administration
• Wafer can be administered to patients experiencing non-traumatic pain where methoxyflurane has proven to be ineffective or cannot be administered.
• Prior to administration of the Ketamine Wafer, patients should be encouraged to rinse mouth with water and swallow
completely.
• Wafer should be placed posterior towards the base of the tongue and medially on either side of the frenulum in the sublingual
space.
.