ANZCA Final Exam flashcards

31 cards. Read the term and the definition here. The deck at the top of this page is optional.

MAC definition

The minimum alveolar concentration of an inhaled anaesthetic at 1 atmosphere that prevents movement in 50% of patients in response to a standard surgical stimulus.

Oxygen delivery formula

Oxygen delivery equals cardiac output multiplied by arterial oxygen content multiplied by ten, where arterial oxygen content depends mainly on haemoglobin and saturation.

Preoxygenation endpoint

An end-tidal oxygen fraction greater than 0.9 indicates adequate denitrogenation, providing a safe apnoea period of several minutes before desaturation during induction.

Suxamethonium contraindications

Avoid suxamethonium in hyperkalaemia, burns or denervation beyond 48 to 72 hours, malignant hyperthermia susceptibility, and pseudocholinesterase deficiency because of dangerous potassium release or prolonged paralysis.

Malignant hyperthermia treatment

Stop volatile agents and give 100% oxygen, then dantrolene 2.5 mg/kg intravenously repeated to 10 mg/kg, with active cooling and treatment of hyperkalaemia and acidosis.

Lipid emulsion dosing

For local anaesthetic systemic toxicity, give 20% lipid emulsion 1.5 mL/kg bolus followed by 0.25 mL/kg/min infusion, repeating the bolus if the patient remains unstable.

Lidocaine maximum dose

With adrenaline, the maximum adult lidocaine dose is 7 mg/kg; without adrenaline it is 3 mg/kg, and doses should be reduced in hepatic impairment and low cardiac output.

Difficult airway declaration

After up to three optimised laryngoscopy attempts, declare failure, maintain oxygenation with a supraglottic device, and proceed to front-of-neck access if oxygenation fails.

Bupivacaine maximum dose

The maximum adult bupivacaine dose is approximately 2 mg/kg regardless of adrenaline, because the drug is highly cardiotoxic and its systemic toxicity can be refractory.

Rapid sequence induction

A technique using preoxygenation, a rapidly acting induction agent, and suxamethonium with cricoid pressure to secure the airway quickly in patients at high aspiration risk.

Opioid equianalgesic conversion

Approximately 30 mg oral morphine equals 20 mg oral oxycodone, 10 mg intravenous morphine, or a 12 mcg/h fentanyl patch; reduce the calculated dose by 25 to 50% for incomplete cross-tolerance.

Neuropathic pain first line

First-line agents are gabapentinoids, tricyclic antidepressants, and serotonin-noradrenaline reuptake inhibitors; opioids are reserved for selected cases because of limited efficacy and dependence risk.

Neuropathic pain features

Neuropathic pain is typically described as burning, shooting, or electric-shock-like, and examination may reveal allodynia, hyperalgesia, or reduced sensation in a dermatomal distribution.

Post-herpetic neuralgia

Pain persisting more than three months after the herpes zoster rash; risk increases with age, and first-line treatment is gabapentin or a tricyclic, with topical lidocaine for localised pain.

Complex regional pain syndrome

Diagnosed using Budapest criteria: continuing pain disproportionate to the inciting event, plus symptoms in three of four categories and signs in two categories, without another explanation.

Cauda equina red flags

Bilateral sciatica, saddle anaesthesia, bladder or bowel dysfunction, and progressive motor deficit require urgent MRI and neurosurgical referral to prevent permanent deficit.

WHO analgesic ladder

A three-step approach for cancer pain: non-opioid for mild pain, weak opioid for moderate pain, and strong opioid for severe pain, with adjuvants added at any step.

Opioid-induced hyperalgesia

A paradoxical state where escalating opioid doses worsen pain and cause diffuse tenderness; management involves reducing the dose or rotating to a different opioid.

Cancer breakthrough pain

A transient flare of pain despite controlled background pain; treat with a short-acting opioid dose proportional to the regular daily requirement, given at onset.

Tricyclic cautions

Avoid or use cautiously in cardiac conduction disease, recent myocardial infarction, glaucoma, urinary retention, and the elderly because of anticholinergic and proarrhythmic effects.

Gabapentinoid mechanism

Gabapentinoids bind the alpha-2-delta subunit of voltage-gated calcium channels, reducing neurotransmitter release; they are renally cleared, so dose reduction is needed in renal impairment.

Revised cardiac risk index

Six predictors: ischaemic heart disease, heart failure, cerebrovascular disease, insulin-treated diabetes, creatinine above 177 micromol/L, and high-risk surgery; each adds one point.

Perioperative beta-blocker rule

Continue established beta-blockers through surgery, but do not initiate high-dose beta-blockade on the day of surgery because it increases the risk of stroke and death.

Perioperative anticoagulation

Warfarin is usually ceased about five days before surgery, with bridging only for high thrombotic risk; direct oral anticoagulants are typically stopped 24 to 48 hours preoperatively depending on renal function.

Perioperative glucose target

Target blood glucose of 6 to 10 mmol/L; an insulin infusion is preferred for poorly controlled diabetes or prolonged procedures, with hourly monitoring to avoid hypoglycaemia.

Enhanced recovery principles

Key elements include carbohydrate loading, avoidance of prolonged fasting, opioid-sparing multimodal analgesia, normothermia, and early mobilisation and feeding after surgery.

Apfel PONV score

Four risk factors: female sex, non-smoker, history of postoperative nausea and vomiting, and postoperative opioids; each adds about 20% risk, guiding multimodal prophylaxis.

Perioperative anaphylaxis

Stop the trigger, give titrated intravenous adrenaline 50 mcg boluses, fluids, and oxygen; take mast cell tryptase at one and four hours after onset to confirm the diagnosis.

VTE prophylaxis selection

Use a validated risk assessment; mechanical prophylaxis suits moderate risk, while high-risk patients generally need low-molecular-weight heparin unless bleeding risk contraindicates it.

Perioperative anaemia

Preoperative anaemia independently predicts morbidity and transfusion; investigate and treat iron deficiency before elective surgery, and use restrictive transfusion thresholds of about 70 g/L.

Postoperative delirium risk

Risk factors include older age, cognitive impairment, sensory deprivation, pain, and polypharmacy; prevention emphasises orientation, early mobilisation, sleep hygiene, and avoiding anticholinergics.