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Egyptian Board Anesthesia study materials
Egyptian Board Anesthesia study resources

Egyptian Board Anesthesia: General Anesthesia and Airway Management

Egyptian Board Anesthesia · Work through your exam, one topic at a time.

All guide sections

General Anesthesia and Airway Management

This domain tests the sequence of decisions that keeps a patient asleep, still, and oxygenated: preoxygenation, induction, airway device choice, maintenance, monitoring, and safe emergence. Expect difficult-airway vignettes and questions on neuromuscular reversal.

Core rules

  • Preoxygenation with a tight seal for 3 minutes, or 8 vital-capacity breaths, replaces alveolar nitrogen with oxygen and lengthens safe apnoea time when FRC is normal.
  • MAC is the alveolar concentration at which 50% of patients do not move to surgical stimulus. MAC values are additive and are reduced by opioids, pregnancy (about 30%), hypothermia, sepsis, and age (roughly 6% per decade after 40).
  • Processed EEG monitoring (BIS 40-60) reduces awareness in high-risk patients, not routinely in everyone.
  • Neuromuscular block is monitored quantitatively; a train-of-four ratio below 0.9 at extubation predicts hypoxaemia and aspiration. Sugammadex 2 mg/kg reverses moderate block (TOF count 2), 4 mg/kg deep block, and 16 mg/kg for immediate rescue after 1.2 mg/kg rocuronium.
  • Cannot intubate, cannot oxygenate in an adult demands front-of-neck access rather than repeated attempts.

Worked example

You plan maintenance with 1.0% end-tidal sevoflurane and 60% nitrous oxide. Taking adult sevoflurane MAC as 2.0%, sevoflurane contributes 1.0/2.0 = 0.5 MAC. Nitrous oxide MAC is about 104%, so 60% contributes 60/104 = 0.58 MAC. Total is 1.08 MAC, adequate for incision without an opioid. Reasoning: convert every agent into a fraction of its own MAC, then add; below roughly 1 MAC, expect movement or awareness unless an adjunct is present.

Traps that cost marks

  • Checking train-of-four count only, never the ratio, before extubation.
  • Giving nitrous oxide to a patient with pneumothorax, bowel obstruction, or middle-ear surgery.
  • Ignoring reduced MAC in obstetric and elderly patients, producing hypotension while the patient is awake.
  • Extubating on 30% oxygen without a cuff-leak test in a patient with a known difficult airway.