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• Care of the Surgical Patient
4

Usually, an anesthesiologist reviews a patient's drugs and stipulates which ones should be taken on the day of surgery. Such a review is necessary because some drugs interact with general anesthetics.

Diabetes: On the day of surgery, patients with insulin-dependent diabetes are typically given one third of their usual insulinSome Trade Names
HUMULIN
NOVOLIN
Click for Drug Monograph
dose in the morning. Those who take oral drugs are given half of their usual dose. If possible, surgery is done early in the day. The anesthesiologist monitors plasma glucose during surgery and gives additional insulinSome Trade Names
HUMULIN
NOVOLIN
Click for Drug Monograph
or dextrose as needed. Close monitoring with fingerstick testing continues throughout the perioperative period.

Corticosteroids: Patients who are taking corticosteroids (mineralocorticoids or glucocorticoids) or have taken them within the previous 3 to 6 mo should be given supplemental doses of these drugs in case perioperative stress (eg, fluid shifts, hypotension) causes adrenal suppression.

Anticoagulants and antiplatelets: Anticoagulants (eg, warfarinSome Trade Names
COUMADIN
Click for Drug Monograph
) and antiplatelet drugs (eg, aspirinSome Trade Names
BUFFERIN
ECOTRIN
GENACOTE
Click for Drug Monograph
) are usually stopped 5 to 7 days before surgery. However, if the procedure has a low risk of bleeding, an anticoagulant may be continued even on the day of the procedure, although the risk of postoperative bleeding slightly increases.

Other drugs that control chronic disorders: Most drugs taken to control chronic disorders, especially cardiovascular drugs (including antihypertensives) should be continued throughout the perioperative period. Most oral drugs can be given with a small sip of water on the day of surgery. Others may have to be given parenterally or delayed until after surgery. Anticonvulsant levels should be measured preoperatively in patients with a seizure disorder.

Drug dependence: Patients who are dependent on drugs or alcohol may experience withdrawal during the perioperative period. Alcoholics should be given prophylactic benzodiazepines (eg, chlordiazepoxideSome Trade Names
LIBRIUM
Click for Drug Monograph
, diazepamSome Trade Names
VALIUM
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, lorazepamSome Trade Names
ATIVAN
Click for Drug Monograph
) starting at admission. Opioid addicts may be given opioid analgesics to prevent withdrawal; for pain relief, they may require larger doses than patients who are not addicted. Rarely, opioid addicts require methadoneSome Trade Names
DOLOPHINE
Click for Drug Monograph
to prevent withdrawal during the perioperative period.

Smoking: Smokers are advised to stop smoking as early as possible before any procedure involving the chest or abdomen. Several weeks of smoking cessation are required for ciliary mechanisms to recover. An incentive inspirometer should be used before and after surgery.

Upper airway: Before intubation, dentures must be removed. Ideally, before patients are moved from the preanesthetic holding area, they should give dentures to a family member. Patients with a deviated septum or another airway abnormality should be evaluated by an anesthesiologist before surgery requiring intubation.

Preprocedural checklist: In the operating room, before the procedure begins, a time out is held during which the team confirms several important factors:

• Patient identity
• Correct procedure and operative site (if applicable)
• Availability of all needed equipment
• Completion of indicated prophylaxis (eg, antibiotics, anticoagulants)

Last full review/revision May 2009 by Robert G. Johnson, MD

Content last modified May 2009