Ketamine

ADMINISTRATION ROUTES:

IV

ALTERNATIVE NAMES:

Ketalar

ICU INDICATIONS:

1. Analgesia
2. Induction of anaesthesia

PRESENTATION AND ADMINISTRATION:

IV:

200 mg/2 mL vial

Compatible with the following IV fluids:

Normal saline, 5% dextrose

Store at room temperature.

For infusion dilute with compatible IV fluid to a dilution of 1 mg/mL (e.g. 50 mg in 50 mL)

DOSAGE:

IV:

Induction of anaesthesia:

100-200 mg IV

Analgesia:

Dilute to 1 mg/mL. & administer bolus doses 1-2 mg (1-2 mL) Infusion 1-10 mg/hr if required

DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:

Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.

DOSAGE IN PAEDIATRICS:

Induction of anaesthesia:

1-2 mg/kg IV

Analgesia:

0-4 mcg/kg/min

CLINICAL PHARMACOLOGY:

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.

CONTRAINDICATIONS:

1. Any condition where severe hypertension would constitute a serious hazard

WARNINGS:

Emergence reactions have occurred in approximately 12% of patients. The psychological manifestations vary in severity between pleasant dream-like states, vivid imagery, hallucinations, and emergence delirium. In some cases these states have been accompanied by confusion, excitement, and irrational behaviour which a few patients recall as an unpleasant experience. The duration ordinarily is no more than a few hours. In a few cases, however, recurrences have taken place up to 24 hours postoperatively. The incidence of these emergence phenomena is least in the young (15 years of age or less) and elderly (over 65 years of age) patient.

PRECAUTIONS:

General:

An increase in intracranial pressure has been reported following administration of ketamine. Use with extreme caution in patients with raised intracranial pressure.

Laboratory Tests:

No tests in addition to routine ICU tests are required.

Drug/Laboratory Test Interactions:

None noted.

IMPORTANT DRUG INTERACTIONS IN ICU:

None of note

ADVERSE REACTIONS:

General:

Anaphylaxis. Local pain and exanthema at the injection site have infrequently been reported. Transient erythema and/or morbilliform rash have also been reported

Cardiovascular:

Blood pressure and pulse rate are frequently elevated following administration of ketamine. However, hypotension and bradycardia have been observed. Arrhythmia has also occurred

Respiratory:

Although respiration is frequently stimulated, severe depression of respiration or apnea may occur following rapid intravenous administration of high doses of ketamine. Laryngospasms and other forms of airway obstruction have occurred during ketamine anaesthesia

Neurological:

In some patients, enhanced skeletal muscle tone may be manifested by tonic and clonic movements sometimes resembling seizures

Gastrointestinal:

Anorexia, nausea and vomiting have been observed; however this is not usually severe