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

Hematologic

Anticoagulation (e.g. warfarin, DOAC)

Case-by-case basis balancing increased risk of intraoperative blood loss with prevention of thromboembolic complication

• AC should be continued if:
  • risk factors of recent stroke, MI, atrial fibrillation, or prosthetic heart valve are present
• AC should be discontinued if:
  • anticipated high surgical blood loss (e.g. CABG)
  • procedure lasting longer than 45 min
  • there is heavy consequence of bleeding (e.g. neurosurgical procedure)
• Timing of discontinuation:
  • Discontinue warfarin 5 days before surgery (with PT/INR day of surgery) with consideration for heparin bridging
  • Discontinue DOAC 1-2 days before surgery depending on bleeding risk

Antiplatelet (e.g. aspirin, clopidogrel)

Case-by-case basis balancing increased risk of intraoperative blood loss with prevention of thromboembolic complication

• DAPT should be continued if:
  • recent stent or bypass procedures, given high likelihood of stenosis
  • non-cardiac procedure
• DAPT should be discontinued if:
  • there is heavy consequence of bleeding (e.g. neurosurgical procedure)

Ideally, a decision is facilitated by surgeon and cardiologist discussion.

Nonsteroidal antiinflammatory drugs (NSAID)

Discontinue 24 hr prior to surgery

• Increased risk of perioperative bleeding
• Could consider continuing if patient's pain control outweighs risk of surgical bleeding

Endocrine (Diabetes)

DPP-4 inhibitors (e.g. sitagliptin)

Continue

• No risk for hypoglycemia, though increased risk of gastric motility changes with continuation

Insulin

Continue basal (long-acting) insulin and discontinue mealtime insulin, but assess on patient-by-patient basis

• Discontinuing insulin increases risk of DKA, particularly in type 1 diabetics
• Continuing insulin increases risk for hypoglycemia, particularly when NPO
• Insulin pumps should remain on basal rate as well
• For long and/or complex surgeries, intraoperative glucose management may include IV insulin and dextrose infusions

Meglitinides (e.g. repaglinide)

Discontinue day of surgery

• Increased risk of hypoglycemia

Metformin

Discontinue day of surgery

• Increased risk of lactic acidosis

GLP-1 agonists (e.g. dulaglutide)

Continue

• No risk for hypoglycemia, though increased risk of gastric motility changes with continuation

SGLT2 inhibitors

Discontinue 3-4 days before surgery

• Increased risk of hypovolemia, AKI, and postoperative euglycemic DKA (elevated ketones, normal glucose)

Sulfonylureas (e.g. glipizide)

Discontinue day of surgery

• Increased risk of hypoglycemia

Thiazolidinediones (e.g. rosiglitazone)

Discontinue day of surgery

• Increased risk of hypervolemia (CHF, peripheral edema)

Endocrine (Non-diabetes)

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 20 mg
• 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

Selective estrogen receptor modulators (SERM)

Continue

• Should be taken with VTE prophylaxis to offset increased VTE risk

Bisphosphonates

Discontinue day of surgery

• Unable to be taken as recommended (with >8 oz water) due to NPO status

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

Psych

Opioids

Consider continuing buprenorphine/methadone therapy

• For patients on opioid agonist therapy with buprenorphine or methadone, consider continuing home dosing in the perioperative period. May require dose reduction of buprenorphine pre-operatively if at doses >8 mg/day.
• Expect higher than usual/more frequent dosing requirements of full agonist mu-receptor agents (i.e. fentanyl, hydromorphone) for adequate pain control.
• Consider non-opioid adjuncts (Tylenol, NSAIDs, GABA agonists, regional techniques, ketamine infusions).