Neuromuscular Blocking Agents, Anticholinesterases, and Specific Reversal Agents — WACS Viva & Clinical Scenarios (Pharmacology and Applied Pharmacology)

Exam-style neuromuscular blocking agents, anticholinesterases, and specific reversal agents viva scenarios with examiner probes and model answers for…

Scenarios covered

• SCENARIO 1: A 34-year-old parturient undergoes emergency Caesarean delivery under general anaesthesia using suxamethonium 1.5 mg/kg for rapid sequence induction. At 45 minutes post-induction, she has made no spontaneous respiratory effort and peripheral nerve stimulation reveals zero twitches on train-of-four. Outline your pharmacological analysis and subsequent management plan.
• SCENARIO 2: A 48-year-old male with end-stage renal disease on maintenance haemodialysis (serum creatinine 680 micromol/L, potassium 5.2 mmol/L) requires emergency laparotomy for perforated appendicitis. Formulate and defend your choice of muscle relaxant and reversal strategy.
• SCENARIO 3: At the conclusion of a 3-hour abdominal surgery, a patient has two weak twitches on train-of-four stimulation. The trainee anaesthetist administers 2.5 mg neostigmine with 1.2 mg atropine. Fifteen minutes later, the patient exhibits persistent muscle weakness, tidal volume of 150 mL, and inability to lift the head. Evaluate this scenario pharmacologically.
• SCENARIO 4: A 24-year-old patient who sustained extensive deep partial-thickness burns 3 weeks ago requires debridement and skin grafting under general anaesthesia. Explain the absolute contraindication to suxamethonium and select an evidence-based alternative.