Ketamine Administration

Ketamine for Procedural Sedation
Medication name Ketamine hydrochloride
Trade name Ketalar

Expected outcomes
That ketamine will used for procedural sedation by appropriate staff and be delivered in accordance with this guideline unless certain modifications are ordered by a medical officer to meet specific patient needs.

The Emergency Consultant or Senior Registrar in Charge must be present in the Emergency Department and approve the use of ketamine for every patient.
The following appropriately qualified staff need to be involved when using ketamine for procedural sedation:
• A medical officer to perform the procedure;
• A medical officer to be solely responsible for administration of medications, monitoring and care of the patient;
• A nurse competent in airways management.
An accredited Emergency Physician (or Senior Registrar for adult patients) with specific experience in airway management and resuscitation must be either directly involved in performance of the procedure or administration of the sedation.

Procedural sedation with ketamine should only be carried out in a designated resuscitation cubicle where the following equipment is available:
• Resuscitation equipment must be readily available;
• ECG monitoring and pulse oximetry;
• Non-invasive blood pressure monitoring;
• Suction, bag-valve-mask (appropriate to age/size of patient) is by the bedside and has been tested;
• Suction equipment.
It should be documented in the medical record or Symphony® that informed consent has been  obtained, including a list of the complications discussed.

Medication class
Anaesthetic adjunct agent (NMDA antagonist)

Actions
Ketamine is a rapid acting general anaesthetic producing an anaesthetic state characterised by profound analgesia, normal pharyngeal/laryngeal reflexes, normal or slightly enhanced skeletal muscle tone, cardiovascular and respiratory stimulation, and occasionally a transient and minimal
respiratory depression.
Clinically the patient will present in a dissociative state, commonly with nystagmus and their eyes open, but the patient will be unresponsive, will feel no pain and have no recollection of the procedure.

Indications
To provide procedural analgesia and sedation for short painful procedures especially those requiring immobilisation. For example:
• Suturing lacerations;
• Reduction of fractures;
• Incision and drainage of an abscess;
• Removal of foreign bodies.

Contraindications
• Age less than 12 months.
• Previous adverse reaction to ketamine.
• Lack of appropriately qualified staff.
• Head injury associated with altered conscious state or vomiting, CNS mass lesion, hydrocephalus, other intracranial hypertension.
• Respiratory tract infection, current breathing difficulty due to excessive respiratory secretions, anatomical abnormality of airway.
• Glaucoma or acute globe injury.
• History of psychosis.
• Poorly controlled seizure disorder.
• Patient currently unstable (fitting, vomiting, hypotensive).
• Acute intermittent porphyria; thyroid disease.
• Congenital heart disease; hypertension.

Precautions
• Oral intake of solids within 4 hours and liquids within 2 hours of sedation (use discretion for urgent procedures such as reduction of fractures with circulatory compromise).
• Age greater than 12 and adults are at increased risk of emergence phenomena; consider if ketamine in the most appropriate sedative agent.
Refer to Adverse reactions section of this guideline.

Pregnancy and Breastfeeding
Pregnancy ADEC Category A. Breastfeeding; limited data, avoid use.

Presentation
200mg/2mL vials

Storage
Ketamine is a schedule 8 medication (Drug of Addiction) and must be stored in a locked medication safe. Store below 30°C; Protect from light.

Pharmacokinetics Route of Administration
 Intramuscular (IM) Intravenous (IV)
Clinical Onset 5 minutes 1 minutes
Duration of effective sedation 15 to 30 minutes 10 to 20 minutes

Baseline investigations
Measure vital signs at baseline (heart rate, respiratory rate, blood pressure and oxygen saturation).
During induction encourage the patients and the patient’s family to talk
about happy topics, particularly in children.

Dosage Ketamine may be safely and effectively administered by either the intramuscular (IM) or intravenous (IV) route and the choice should be based on practical considerations. The IV route is often preferred because of its titratability, however access may be difficult.

Intravenous
Initial dose: 1 to 1.5mg/kg (rounded to the nearest 10mg for adults and 5mg for paediatrics)
Titration doses: titrate to effect or prolong sedation with increments of 0.5mg/kg (rounded to the nearest 10mg for adults and 5mg for paediatrics)

Intramuscular
Initial dose: 3 to 4mg/kg (rounded to the nearest 20mg for adults 10mg for paediatrics)
Titration doses: repeat dose after 10 minutes if sedation is inadequate

Adjunct Medications
Adjunctive premedications have commonly been used with ketamine; however there is little evidence to support their use.

Atropine
0.01 to 0.02mg/kg IM or IV, to a maximum of 0.6mg, has been suggested to reduce hypersecretions. It may be added to the same syringe and administered with the initial dose of ketamine.

Midazolam
Has been used to ameliorate severe emergence phenomena however routine use is not recommended.

Administration
INTRAVENOUS
Separate syringes are required for the initial dose and two titration
doses.
Step 1: Draw up contents of 2mL ketamine vial (200mg) and dilute to 20mL in a 20mL syringe with sodium chloride 0.9% to give a 10mg/mL solution.
Ensure syringe is labelled with “ketamine 200mg/20mL”.
Note: for patient’s greater than 80kg, two vials of ketamine may need to be diluted.

Step 2: From the diluted solution, draw out the volume required for the initial dose and two titration doses into three separate syringes. Ensure each syringe is labelled with “ketamine total mg / total mL”. Refer to Table 1 for required volumes.

Step 2: Administer initial dose as a slow IV push over 1 to 2 minutes as rapid administration has been associated with respiratory depression.

Step 3: Continue to administer titration doses as a slow IV push over 1 to 2 minutes as required.

Step 4: Discard any unused ketamine solution.

Table 1: Volume of ketamine required using 10mg/mL solution
Dose (mg) Volume (mL) Dose Volume (mL)
5mg 0.5mL 60mg 6mL
10mg 1mL 65mg 6.5mL
15mg 1.5mL 70mg 7mL
20mg 2mL 80mg 8mL
25mg 2.5mL 90mg 9mL
30mg 3mL 100mg 10mL
35mg 3.5mL 110mg 11mL
40mg 4mL 120mg 12mL
45mg 4.5mL 130mg 13mL
50mg 5mL 140mg 14mL
55mg 5.5mL 150mg 15mL

Handling and Disposal
Ketamine is a Schedule 8 medication (Drug of Addiction) and must be handled in accordance with the legislation.
• The prepared ketamine syringes must NOT be left unattended.
• Once the procedure has been completed dispose of any unused portion immediately.
• Unused portions are to be disposed of and witnessed by two registered nurses by flushing down the sink with running water.
• Record disposal in the Drug of Addiction register in the notes/comments column beside the entry made under the patient’s name.

Administration
INTRAMUSCULAR
Separate syringes are required for the initial dose and two titration doses.
Step 1: From the 200mg/2mL vial, draw out the volume required for the initial dose and two titration doses into three separate syringes. Ensure each syringe is labelled with “ketamine total mg / total mL”. Refer to Table 2 for required volumes. More than one vial may be required.

Step 2: Administer initial dose undiluted as an IM injection.

Step 3: Continue to administer titration doses undiluted as an IM injection as required.

Step 4: Discard any unused ketamine solution.

Table 2: Volume of ketamine required using 100mg/mL vial
Dose (mg) Volume (mL) Dose Volume (mL)
30mg 0.3mL 160mg 1.6mL
40mg 0.4mL 180mg 1.8mL
50mg 0.5mL 200mg 2mL
60mg 0.6mL 220mg 2.2mL
70mg 0.7mL 240mg 2.4mL
80mg 0.8mL 260mg 2.6mL
90mg 0.9mL 280mg 2.8mL
100mg 1mL 300mg 3.0mL
110mg 1.1mL 320mg 3.2mL
120mg 1.2L 340mg 3.4mL
130mg 1.3mL 360mg 3.6mL
140mg 1.4mL 380mg 3.8mL
150mg 1.5mL 400mg 4mL
Handling and Disposal
Ketamine is a Schedule 8 medication (Drug of Addiction) and must be handled in accordance with the legislation.
• The prepared ketamine syringes must NOT be left unattended.
• Once the procedure has been completed dispose of any unused portion immediately.
• Unused portions are to be disposed of and witnessed by two registered nurses by flushing down the sink with running water.
• Record disposal in the Drug of Addiction register in the notes/comments column beside the entry made under the patient’s name.

Monitoring During the procedure
• Pulse oximetry and ECG monitoring is required.
• Record vital signs at 5 minute intervals.
• Observe the airway and chest movements to monitor for airway malposition.

Post procedure
• Patients must be nursed 1:1 by an Advanced Life Support (ALS) accredited registered nurse until the patient is interactive.
• The patient must be accompanied by a nurse, relative or carer until return to pre-treatment level of awareness and verbalisation.
• Nurse in the recovery position in a quiet area with dim lighting to minimise emergence phenomena. Do not stimulate prematurely.
• Continue pulse oximetry and continuous cardiac monitoring.
• Record vital signs at 5 minute intervals until the patient is interactive and then at 30 minute intervals until patients is safe for discharge.
• Nil by mouth until return to pre-treatment level of awareness.

Discharge Criteria (usually 90 to 120 minutes post procedure)
• Normal vital signs appropriate to patient’s age
• Return to pre-treatment level of awareness and verbalisation
• Able to tolerate liquids
• Ensure family/carer observation and no independent ambulation for at least 2 hours post discharge

Significant (in)compatibilities
Compatible fluids
Sodium chloride 0.9%, glucose 5%
Refer to the Product Information or Australian Injectable Drugs Handbook for a comprehensive list.

Significant interactions
Refer to the Product Information for a comprehensive list.

Adverse reactions Common adverse reactions
• Raised BP and pulse rate, particularly at induction (expected)
• Nystagmus (expected)
• Lacrimation and hypersalivation (up to 50% of patients)
• Emesis (up to 12% of patients)
• Increased muscle tone (sometimes tonic-clonic and resembling seizures)
• Respiratory depression, associated with rapid IV administration (rare)
• Raised intracranial pressure and raised intraocular pressure (rare)
• Laryngospasm (up to 1% of patients)
• Rare, transient complication, manage with gentle positive pressure ventilation

Emergence Phenomena (2% of children and up to 30% in adults)
May occur during recovery and for up to 24 hours. They include vivid (possibly unpleasant) dreams, restlessness, confusion, hallucinations and irrational behaviour. Less common in children, the elderly and after IM administration, and by minimising stimulation during the recovery period.
Treatment with a small dose of midazolam titrated to effect may be necessary for severe reactions.