The Gupta Perioperative Risk calculator is designed to estimate the risk of myocardial infarction or cardiac arrest around the time of surgery. It considers five key patient-specific inputs and computes a percentage risk that helps clinicians assess the likelihood of these cardiac events during or after surgery.

To conduct this assessment, the calculator requires the following inputs:

- **Age**: The calculator uses the patient's age, calculated as age multiplied by a coefficient, contributing incrementally to the risk.
  
- **Functional Status**: Here you can select from three levels, each impacting risk differently:
  - Independent: No additional risk
  - Partially Dependent: +0.65 to risk
  - Totally Dependent: +1.03 to risk

- **ASA Class (American Society of Anesthesiologists Classification)**: This classification assesses the physical status of the patient, with risk coefficients for each class:
  - 1: Normal healthy patient = -5.17
  - 2: Mild systemic disease = -3.29
  - 3: Severe systemic disease = -1.92
  - 4: Severe systemic disease that poses a constant threat to life = -0.95
  - 5: Moribund, not expected to survive without surgery = 0
  
- **Creatinine Level**: Indicates kidney function with potential influences such as:
  - Normal (≤1.5 mg/dL, 133 µmol/L): No additional risk
  - Elevated (>1.5 mg/dL, 133 µmol/L): +0.61 to risk
  - Unknown: -0.1 to risk

- **Procedure Type**: Represents the surgical context with diverse coefficients determined by the expected complexity and risk of each procedure. Examples include:
  - Anorectal: -0.16
  - Aortic: +1.6
  - Bariatric: -0.25
  - Cardiac: +1.01
  - Brain: +1.4

In calculating cardiac risk, the user's specific choices for each category are assigned predetermined coefficients. The age contributes by multiplying the age value by 0.02, reflecting its increasing influence as age advances. Each option selected contributes to a cumulative 'x' score, calculated as follows:

x = -5.25 + (age * 0.02) + functional status coefficient + ASA class coefficient + creatinine level coefficient + procedure type coefficient

Using the logistic function, the score is converted into a percentage risk:

cardiacRisk = (exp(x) / (1 + exp(x))) * 100

This percentage provides the risk of myocardial infarction or cardiac arrest during the perioperative period. Understanding these results enables healthcare professionals to discuss potential risks with patients, contributing to the informed decision-making process regarding surgical interventions. This comprehensive assessment blends individual patient characteristics with procedural factors to predict cardiac risk effectively.

The Gupta Perioperative Risk for Myocardial Infarction or Cardiac Arrest (MICA) estimates the likelihood of cardiac complications in patients undergoing surgery. It calculates risk as a percentage based on variables including age, functional status, ASA class, serum creatinine levels, and the type of procedure. Each factor is assigned a specific value, which contributes to a logistic regression equation, providing a percentage risk score. The model is widely used to stratify risk and guide perioperative management.