Woo Perioperative Risk

Risk estimation of stroke, cardiac and mortality risk after non‐cardiac surgery


This surgical risk calculator is particularly useful when a clinician wants to assess postoperative 30-day risk of stroke and all-cause mortality in addition to cardiac risk (myocardial infarction, cardiac arrest) after non-cardiac surgery.

Commonly used preoperative cardiac risk calculators such as the Revised Cardiac Risk Index (RCRI), Gupta Myocardial Infarction or Cardiac Arrest (MICA) and ACS NSQIP surgical risk calculator do not provide risk estimation of stroke, a major surgical complication with high morbidity and mortality.

This surgical risk model was developed and validated in over 1 million patients (N= 1,165,750 ) from ACS-NSQIP (American College of Surgeons-National Surgical Quality Improvement Program).

This model had high predictive performance with area under the receiver operating characteristic curve for stroke (training cohort=0.869, validation cohort=0.876), major cardiovascular events-cardiac risk and/or stroke (training cohort=0.871, validation cohort=0.868), cardiac risk (training cohort=0.879, validation cohort=0.872 ), and 30-day mortality (training cohort=0.922, validation cohort=0.925).

Individualized risk assessment of stroke, cardiac complications, and mortality may help clinicians better counsel patients and inform surgeons and possibly implement measures to lower the risk.

This calculator provides only risk estimate and individual surgical outcome may be different from the risk estimate of this risk calculator.


Sang H. Woo et al

Journal of the American Heart Association Cardiovascular and Cerebrovascular Disease, February 2021

The Woo Perioperative Risk calculator is created by QxMD.

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