Question 1

What is the difference between ASA III and ASA IV?

Accepted Answer

ASA III is severe systemic disease that substantively limits function but is not an immediate threat to life — for example COPD, dialysis-dependent renal failure, or a cardiac event more than three months ago. ASA IV is severe disease that is a constant threat to life: a myocardial infarction, stroke or stent within the last three months, ongoing ischaemia, severe valve disease, sepsis or DIC. Add the suffix 'E' for an emergency procedure.

Question 2

Which bedside signs predict a difficult airway?

Accepted Answer

No single sign is reliable, so combine them: limited mouth opening, a short thyromental distance, Mallampati III–IV, reduced neck extension, inability to prolong the mandible (upper-lip-bite test class III), retrognathia or prominent incisors, a high BMI with a short neck, and obstructive sleep apnoea. A previous difficult intubation, a neck mass, prior radiation or stridor is a red flag on its own. The more predictors present, the higher the risk — plan adjuncts, senior help and a difficult-airway trolley accordingly.

Question 3

What are the standard preoperative fasting times?

Accepted Answer

The widely used '2–4–6–8' rule: 2 hours for clear fluids, 4 hours for breast milk, 6 hours for infant formula or a light meal, and 8 hours for fried or fatty food and meat. Encouraging clear fluids up to two hours improves comfort and is endorsed by guidelines; gastroparesis, significant reflux and recent GLP-1 agonist use may warrant a longer interval or aspiration precautions.

Pre-anaesthesia checkup

1 · ASA Physical Status

2 · Difficult-airway predictors

3 · Fasting (2–4–6–8)

Key sources