Ketamine Anaesthesia (A Review and Personal Experience in some clinical cases of Ketamine-Diazepam anaesthesia)

Abstract

A literature Survey of ketamine anaesthesia has been reviewed

including personal clinical experience in some cases.

Ketamine hydrochloride (Ketalar) has been found to be a

good anaesthetic agent with strong analgesic and hypnotic properties.

The coly drawback is its cardiovascular stimulating effects which

are not desirable in certain situations. There is an increase in

both systolic and ~ diastolic blood pressure as well as pulse rate.

This is associated with an increase in cardiac output, and coronary

blood flow. Cerebral blood flow is also increased. Despite the

increase in coronary blood flow, there is a reduction in the total

oxygen contents in the coronary sinus because of an increased

myocardial oxygen consumption. The increase in blood pressure,

however, makes Ketamine a drug of choice for induction of

anaesthesia in shocked patients.

Because of the above-mentioned cardiovascular stimulating properties

Ketamine bas to be used with caution in heart surgery, pre-existing hypertension, and coronary insufficiency. In obstetrics it has also 1\ to be used with caution because it can cross the placenta easily due to

its high lipid solubility.

The other problem with ketamine anaest.'1es is its psychotomimetic

effects which affect,' mostly adults. These make' the drug rather

unpopular. However, premedication with drugs such as diazepam or lorazepam reduces the psychic effects and increases patients

acceptability to ketamine anaesthesia.

Other drugs have been tried for the reduction of its

carddovascul.ar- stimulating effects. Lobetalol which has both ∞ and β blocking properties he s proved to be a promising drug and is

worth of further investigations. In developing countries such as

Tanzania ketmnine proves to be a very useful drug. It is very popular

and has been administered by less qualified people. Complications

might have happened without much notice due to Lack of proper documentation,

as it is with the other fields of Medicine. It is therefore advisable

to teach all people who will administer Ketamine anaesthesia to be

aware of the technique indications, contraindications and complications

of the drug. Lastly ketamine anaesthesia is a rather expensive method

of administering anaesthesia and should not therefore, whenever possible,

replace other conventional methods such as regional block techniques