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
