Preoperative medication management

Patients often have a long list of medications they take, and decisions must be made about whether to continue or hold them prior to surgery.

Cardiovascular

Beta blockers

Continue if taking chronically

• Reduces coronary ischemia
• Acute withdrawal of chronic beta blocker associated with increased morbidity/mortality

ACE inhibitors/Angiotensin receptor blockers (ARB)

Discontinue morning of surgery. However, could consider continuing for certain cardiac procedures on patient-by-patient basis

• Inhibition of RAAS leads to refractory intraoperative hypotension
• For most surgeries, appears to be no increase in mortality or cardiovascular events from holding ACE/ARB
  • However, some studies suggest myocardial protection in CABG

Diuretics

Discontinue morning of surgery if taking for hypertension and euvolemic

Continue if unstable volume status or history of poorly controlled heart failure

• Theoretical risk of worsened hypotension due to intravascular depletion, though limited studies showing this in practice
• Theoretical risk of hypokalemia, though this has not been observed in practice

Calcium channel blockers

Continue

• Limited data showing neither benefit nor harm with continuation

Alpha 2 agonists (e.g. clonidine)

Continue if taking chronically

• Prevent rebound hypertension

Digoxin

Continue

• Limited data, though no evidence of adverse effects from continuation

Statins

Continue

• Shown to prevent vascular events perioperatively

Endocrine

Glucocorticoids

Continue, but consider stress dosing for patients on high-dose steroids or surgeries of long duration:

• Stress dosing is indicated if daily dose (>3 weeks) is at least:
  • Dexamethasone 2 mg
  • Hydrocortisone 80 mg
  • Methylprednisolone 16 mg
  • Prednisone 20mg
• No stress dose is indicated if daily less less than:
  • Any dose of steroid taken for less than 3 weeks
  • Dexamethasone 0.5 mg
  • Hydrocortisone 20 mg
  • Methylprednisolone 4 mg
  • Prednisone 5 mg
• For intermediate range, defer to patient history and HPA axis evaluation

If stress dose is indicated, hydrocortisone 300 mg/day (or equivalent) is common practice

Note: Avoid etomidate as an induction agent due to increased risk of adrenal crisis

Levothyroxine

Continue

• To maintain euthyroid state
• Can be given IM/IV at 80% dose if necessary

Methimazole/Propylthiouracil (PTU)

Continue

• To maintain euthryoid state

Oral contraceptives (OCP)

Continue unless patient is has high risk of venous thromboembolism (VTE), in which case stop 4 weeks before surgery

• If continued, requires perioperative VTE prophylaxis

Pulmonary

Beta agonists

Continue

• Significant reduction in COPD/asthma complications

Anticholinergics

Continue

• Significant reduction in COPD/asthma complications

Glucocorticoids (inhaled)

Continue

• Avoids risk of adrenal insufficiency, particularly during stress of surgery
• Inhaled dosage relatively low and unlikely to cause adverse events

Gastrointestinal (GI)

H2 blockers/Proton pump inhibitors (PPI)

Continue

• Very safe intraoperatively
• Prevents stress ulcers
• Prevents gastric aspiration/chemical pneumonitis