ANZCA Final Exam cheat sheet

Inhalational MAC values (approximate, 40-year-old): sevoflurane 2.0%, isoflurane 1.15%, desflurane 6.0%, nitrous oxide 105%; MAC decreases ~6% per decade after age 40.

Oxygen delivery: DO2 = CO × CaO2 × 10; CaO2 (mL/dL) = 1.34 × Hb × SaO2 + 0.003 × PaO2.

Rapid-sequence induction in adults: preoxygenation ≥3 min to ETO2 >0.9, then induction agent followed immediately by suxamethonium 1-1.5 mg/kg IV.

Suxamethonium is contraindicated in hyperkalaemia, major burns or denervation beyond ~48-72 h, malignant hyperthermia susceptibility, and known pseudocholinesterase deficiency.

Malignant hyperthermia: dantrolene 2.5 mg/kg IV repeated to a total of 10 mg/kg; stop volatile agents, give 100% oxygen at high flow, treat hyperkalaemia and acidosis.

Difficult airway algorithm: optimise oxygenation, limit attempts (max 3-4 laryngoscopies), declare failure early, and proceed to supraglottic rescue or front-of-neck access.

Local anaesthetic maximum doses (adult, with adrenaline): lidocaine 7 mg/kg, bupivacaine 2 mg/kg, ropivacaine 3 mg/kg; without adrenaline lidocaine 3 mg/kg and bupivacaine 2 mg/kg.

Lipid emulsion for local anaesthetic systemic toxicity: 20% intralipid 1.5 mL/kg bolus, then infusion 0.25 mL/kg/min; repeat bolus if unstable.

Opioid conversion (oral morphine equivalent): oral morphine 30 mg = oral oxycodone 20 mg = oral hydromorphone 6 mg = IV morphine 10 mg = fentanyl patch 12 mcg/h (approximate).

Neuropathic pain first-line agents: gabapentinoids (gabapentin, pregabalin), tricyclics (amitriptyline, nortriptyline), and SNRIs (duloxetine, venlafaxine); opioids are not first-line.

Nociceptive versus neuropathic differentiation: neuropathic pain is described as burning, shooting, or electric-shock-like, with allodynia, hyperalgesia, or dysaesthesia on examination.

Post-herpetic neuralgia: pain persisting >3 months after rash; risk rises with age; first-line treatment is gabapentin or a tricyclic, with topical lidocaine for localised pain.

Complex regional pain syndrome (Budapest criteria): continuing pain disproportionate to the inciting event, plus at least one symptom in three of four categories and one sign in two categories.

Cauda equina syndrome red flags: bilateral sciatica, saddle anaesthesia, bladder or bowel dysfunction, and progressive motor deficit; requires urgent MRI and surgical referral.

Cancer pain: follow the WHO analgesic ladder, prescribe regular paracetamol/NSAID plus opioid with breakthrough doses, and add adjuvants for neuropathic or bone pain.

Opioid-induced hyperalgesia: escalating opioid dose with worsening pain and diffuse tenderness; management is opioid reduction or rotation, not further escalation.

Revised cardiac risk index (RCRI) predictors: ischaemic heart disease, heart failure, cerebrovascular disease, insulin-treated diabetes, chronic kidney disease (creatinine >177 micromol/L), and high-risk surgery.

Perioperative beta-blockade: continue established beta-blockers; do not start high-dose beta-blockers on the day of surgery because of increased stroke and mortality risk.

Venous thromboembolism prophylaxis: use a validated risk assessment; mechanical prophylaxis for moderate risk, and low-molecular-weight heparin for high-risk patients unless contraindicated.

Perioperative anticoagulation: stop warfarin ~5 days preoperatively and bridge with LMWH only in high thrombotic risk; direct oral anticoagulants are usually ceased 24-48 h before surgery depending on renal function.

Perioperative hyperglycaemia: target blood glucose 6-10 mmol/L; insulin infusion is preferred for poorly controlled diabetes or prolonged procedures.

Enhanced recovery after surgery: carbohydrate loading, avoidance of prolonged fasting, opioid-sparing multimodal analgesia, normothermia, and early mobilisation and feeding.

Postoperative nausea and vomiting prophylaxis: use Apfel risk factors (female sex, non-smoker, history of PONV, postoperative opioids) to guide multimodal antiemetic prophylaxis.

Perioperative anaphylaxis: stop the trigger, give adrenaline 50 mcg IV boluses titrated to effect, fluids, and take mast cell tryptase samples at 1 h and 4 h after onset.