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Pre-operative assessment and peri-operative drug management
Pre-operative assessment combines the risk of the operation, the patient's condition and functional capacity; further tests are done only when they would change the decision, and anticoagulants and antiplatelet drugs are stopped and restarted by weighing bleeding risk against thrombotic risk.
Why it matters in the exam
The exam presents a patient coming for elective surgery with comorbidities and medications and asks for the right step: stress test, echocardiogram, blood tests, or straight to surgery. The recurring principle is that a patient who can climb two flights of stairs without symptoms (4 METs or more) usually needs no further cardiac work-up, and that emergency surgery is not delayed for work-up. The European guidelines add an ECG, troponin and BNP for older patients or those with risk factors before intermediate- or high-risk surgery.
Many questions concern drugs: when warfarin is stopped and when heparin "bridging" is needed (only at high thrombotic risk, such as a mechanical mitral valve or a recent stroke), how many days before surgery clopidogrel, ticagrelor and prasugrel are stopped, when a DOAC is stopped according to kidney function and bleeding risk, and why beta-blockers and statins are continued but a beta-blocker is not started on the day of surgery. Candidates are also asked about stopping SGLT2 inhibitors at least 3 days before surgery (risk of ketoacidosis), steroid "stress" dosing, fasting times, and postponing elective surgery after a myocardial infarction or a stent.
Key points
- Two flights of stairs (4 METs or more) — usually no cardiac work-up; emergency surgery is not delayed.
- Warfarin — stop 5 days before, bridge only at high thrombotic risk; DOAC — 1–2 days, no bridging.
- Clopidogrel — 5 days; ticagrelor — 3–5 days; prasugrel — 7 days; aspirin — continue in most cases.
- Continue beta-blockers and statins; SGLT2 inhibitors — stop at least 3 days before.
- Fasting: clear fluids up to 2 hours before, a light meal up to 6 hours before.
Summary table
| Area | The rule | Exam note |
|---|---|---|
| Functional capacity | Climbing two flights of stairs without symptoms = 4 METs or more | If yes — usually no further cardiac work-up |
| Antiplatelet drugs | Aspirin for secondary prevention — continue for most operations; clopidogrel — stop 5 days before; ticagrelor — 3–5 days; prasugrel — 7 days | After a stent — do not stop both drugs without consulting a cardiologist |
| Warfarin | Stop 5 days before, INR below 1.5 on the day of surgery | Heparin bridging only at high thrombotic risk (mechanical mitral valve, recent stroke) |
| DOAC | Stop 1–2 days before according to bleeding risk; longer with dabigatran and reduced kidney function | No bridging |
| Diabetes and other drugs | SGLT2 inhibitor — stop at least 3 days before; metformin — not on the day of surgery; beta-blocker and statin — continue | Do not start a beta-blocker on the day of surgery |
| Timing of elective surgery | After myocardial infarction — at least 60 days; after an elective stent — ideally 6 months; after an acute coronary syndrome — ideally 12 months | Emergency surgery is not delayed for work-up |
| Fasting | Clear fluids up to 2 hours before; a light meal up to 6 hours before | Unnecessary prolonged fasting is harmful |
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Sources
- ESC Guidelines on cardiovascular assessment and management of patients undergoing non-cardiac surgery, 2022 — Pre-operative risk assessment, tests and peri-operative drug management
- ACC/AHA/multisociety Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery, 2024 — Functional capacity, testing and timing after coronary events
- American College of Chest Physicians guideline on perioperative management of antithrombotic therapy, 2022 — Interruption and bridging of anticoagulants and antiplatelet drugs
- American Society of Anesthesiologists practice guidelines for preoperative fasting, 2017 (updated 2023) — Fasting intervals for clear liquids and food
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.