Understanding Anesthesiology - The Global Regional Anesthesia ...

Premedication
Pre-medication can include medication that the patient
takes routinely as well as medication that may be prescribed
specifically for the pre-operative period. Generally
speaking, patients should be given their usual
medication on the morning of surgery with a sip of water.
It is particularly important that patients receive
their usual cardiac and antihypertensive medications
pre-operatively. Discontinuation of beta-blockers, calcium
channel blockers, nitrates or alpha-2 agonists (clonidine)
can lead to rebound hypertension or angina.
Similarly, most medications taken for chronic disease
should be continued on the morning of surgery as well
as throughout the peri-operative period. This is particularly
important for most antidepressants, thyroid replacement
and anticonvulsants.
There are certain medications that may need to be discontinued
in the pre-operative period. Examples include
monoamine oxidase inhibitors and anticoagulants.
Patients on platelet inhibitors such as aspirin represent
a special group of patients who must be considered
on an individual basis such that the risk of stopping
the aspirin is weighed against the risk of surgicalsite
bleeding. For example, a patient who is on aspirin
because of the recent insertion of a coronary stent must
receive their aspirin throughout the peri-operative period.
On the other hand, if the patient is on aspirin for
primary prevention then it is usually discontinued a
full week before surgery to allow return of normal
platelet function.
Some medications are ordered specifically for the preoperative
period. Examples include anxiolytics, antibiotics,
bronchodilators, anti-anginal medication and
anti-emetics. Beta blockers have been used to reduce
the incidence of cardiac morbidity and mortality in
high-risk patients undergoing high-risk procedures, although
the impact of this intervention is not yet fully
understood.
Currently, pre-operative sedation is used less frequently
than it has been in the past as it can delay
awakening at the end of anesthesia. A delayed recovery
is particularly undesirable in the outpatient surgical
population where a return of cognitive function is required
prior to discharge home. Furthermore, a preoperative
visit has been shown to be at least as effective
as pharmacologic means in allaying anxiety in surgical
patients. Nonetheless, there is a role for pre-operative
sedation in very anxious patients or in those for whom
anxiety would be deleterious, such as the cardiac patient.
For most types of surgery, antibiotics are ordered preoperatively
to reduce the incidence of wound infection.
Antibiotics may also be ordered to reduce the risk of
bacterial endocarditis in at-risk patients though the
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