Sun28November0440PM 24

The use of ketamine is best avoided in the following conditions:

True / False

Glaucoma Correct

Porphyria Incorrect answer selected

Hypothyroidism Correct

Epilepsy Correct

Malignant hyperthermia Correct

Explanation

Although ketamine is known to increase muscle tone it has been safely used in malignant hyperthermia.

A small increase in intraocular and intracranial pressure occurs with ketamine use but is used in special clinical situations. In paediatric anaesthesia it can be used to assess the intraocular pressure(IOP) in small children with suspected glaucoma where sevoflurane will significantly reduce IOP.

Ketamine may precipitate tachycardia in untreated hyperthyroidism. Seizure activity is not thought to increase with ketamine use.

Though controversial, ketamine has been implicated as a trigger of a porphyric reaction particularly in high concentrations.

At doses used for clinical anaesthesia, ketamine appears to be safe. With alternate induction agents (propofol), ketamine is best avoided.