Medical Mnemonics
Anaesthesiology Mnemonics
Anaesthesiology is a speciality of checklists and thresholds, where recall must be immediate because the patient is asleep. The mnemonics below hold the preoperative assessment, the airway and fasting rules, the toxicity syndromes and the arrest algorithm that structure daily practice. Several capture the numbers examiners insist on, from MAC values to fasting intervals. Use each acronym as a working checklist rather than trivia: knowing the triggers of malignant hyperthermia or the steps of local anaesthetic toxicity guides the first, decisive minutes. Each entry maps to a core NMC competency and to the routines that keep theatre and recovery safe.
MedNext Academy | 3 min read
Anaesthesiology Mnemonics
Anaesthesiology is a speciality of checklists and thresholds, where recall must be immediate because the patient is asleep. The mnemonics below hold the preoperative assessment, the airway and fasting rules, the toxicity syndromes and the arrest algorithm that structure daily practice. Several capture the numbers examiners insist on, from MAC values to fasting intervals. Use each acronym as a working checklist rather than trivia: knowing the triggers of malignant hyperthermia or the steps of local anaesthetic toxicity guides the first, decisive minutes. Each entry maps to a core NMC competency and to the routines that keep theatre and recovery safe.
Anaesthesiology is a speciality of checklists and thresholds, where recall must be immediate because the patient is asleep. The mnemonics below hold the preoperative assessment, the airway and fasting rules, the toxicity syndromes and the arrest algorithm that structure daily practice. Several capture the numbers examiners insist on, from MAC values to fasting intervals. Use each acronym as a working checklist rather than trivia: knowing the triggers of malignant hyperthermia or the steps of local anaesthetic toxicity guides the first, decisive minutes. Each entry maps to a core NMC competency and to the routines that keep theatre and recovery safe.
Mnemonics and expansions
- **ASA 1 to 6:** 1 healthy, 2 mild systemic disease, 3 severe systemic disease, 4 threat to life, 5 moribund, 6 brain-dead donor. Grades physical status before anaesthesia and predicts perioperative risk.
- **AMPLE:** Allergies, Medications, Past history, Last meal, Events leading to surgery. A rapid preoperative history framework covering the anaesthetically critical points.
- **STOP-BANG:** Snoring, Tiredness, Observed apnoea, Pressure (hypertension), BMI over 35, Age over 50, Neck over 40 cm, male Gender. Screens for obstructive sleep apnoea; a score of three or more is high risk.
- **LEMON:** Look externally, Evaluate 3-3-2, Mallampati, Obstruction, Neck mobility. Predicts a difficult airway; two or more abnormal findings should prompt a difficult-airway plan.
- **2-4-6-8:** 2 hours clear fluids, 4 hours breast milk, 6 hours light meal, 8 hours heavy or fatty meal. The preoperative fasting intervals; clear fluids up to 2 hours improve comfort without raising aspiration risk.
- **LAST:** Lips (perioral tingling), Auditory (tinnitus), Seizures, Toxicity to the heart. The progression of local anaesthetic systemic toxicity; treat with lipid emulsion.
- **CRISP:** Coagulopathy, Refusal, Infection at the site, Spinal cord compression or raised ICP, Pharmacological allergy to local anaesthetic. Absolute contraindications to neuraxial anaesthesia.
- **4 Hs and 4 Ts:** Hypoxia, Hypovolaemia, Hypo or hyperkalaemia, Hypothermia; Tension pneumothorax, Tamponade, Toxins, Thrombosis. The reversible causes to run through in every cardiac arrest.
- **Half Is So Damn Nice:** MAC ascending: Halothane 0.75, Isoflurane 1.15, Sevoflurane 2.0, Desflurane 6.0, Nitrous oxide 104. Orders the volatile agents by minimum alveolar concentration; the lowest MAC is the most potent.
- **Volatile Sux, Dantrolene:** Volatile agents and suxamethonium trigger malignant hyperthermia; dantrolene treats it. Stop the trigger and switch to total intravenous anaesthesia while giving dantrolene.
- **SLUDGE:** Salivation, Lacrimation, Urination, Defecation, GI cramps, Emesis. The cholinergic features of organophosphate poisoning; atropine is titrated to drying of secretions.
- **SOAP:** Suction, Oxygen (preoxygenate), Airway equipment, Pharmacology. The checklist to prepare before a rapid sequence induction.
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