AS3.{1,4-5} | Principles, Testing and Fitness Decisions in Preoperative Evaluation — Summary & Reflection

KEY TAKEAWAYS

The preoperative evaluation is a structured clinical assessment with three goals: risk identification, risk optimisation, and anaesthetic planning. Its principles are: risk stratification is always patient- and procedure-specific; 'fitness for surgery' is a risk-benefit judgement, not a binary pass/fail; and the assessment must be documented and communicated. The ASA Physical Status classification (I-VI, E suffix for emergency) grades systemic disease severity — it does not grade operative risk or airway difficulty. The Mallampati classification (I-IV) grades the oropharyngeal view as an airway predictor — a completely separate scale. Preoperative fasting follows the ASA '2-4-6-8 rule' (clear fluids 2 h, breast milk 4 h, formula/light meal 6 h, fatty/fried/meat 8 h). Investigations are chosen by clinical indication — FBC for suspected anaemia, U&E for renal disease or diuretics, ECG for cardiovascular disease, CXR for cardiac failure or significant respiratory disease. The RCRI scores six factors to estimate MACE risk before non-cardiac surgery. Fitness decisions integrate modifiable and non-modifiable risk factors, with clear documentation of the decision and any outstanding concerns.

REFLECT

Consider a 55-year-old woman with Type 2 diabetes on metformin and insulin, moderate obesity, and treated hypertension who is scheduled for elective laparoscopic cholecystectomy. What is her ASA class? What investigations would you order, and what clinical findings would change your decisions? What medication adjustments would you make before surgery? What would your preoperative note say to the surgical team? Write your reasoning in a structured format — history findings, examination findings, investigations, ASA class, RCRI score, fitness decision, and anaesthetic plan. Then compare your reasoning with the principles covered in this module.