Tools

Renal

eGFR: CKD-EPI 2021 (creatinine, race-free)Creatinine clearance: Cockcroft-Gault Fractional excretion of sodium (FENa) and urea (FEUrea)

Acid-base & electrolytes

Anion gap, albumin-corrected gap, delta ratio Expected PaCO₂ in metabolic acidosis: Winter's formula Albumin-corrected calcium Glucose-corrected sodium Calculated osmolality and osmolar gap Alveolar-arterial (A-a) oxygen gradient Free-water deficit in hypernatraemia Sodium change per litre of infusate: Adrogué-Madias Potassium deficit estimate in hypokalaemia

Units & conversions

Lab units converter: mg/dL, mmol/L, µmol/L, mEq/L

Cardiovascular

CHA₂DS₂-VASc: stroke risk in atrial fibrillation HAS-BLED: bleeding risk on anticoagulation HEART score: chest pain in the ED Corrected QT: Bazett and Fridericia Mean arterial pressure and shock index Revised Cardiac Risk Index (Lee): perioperative risk

Respiratory & VTE

Wells score: pulmonary embolism PERC rule: PE rule-out criteria Age-adjusted D-dimer cut-off Wells score: deep vein thrombosis Light's criteria: pleural effusion CURB-65: community-acquired pneumonia severity

Deterioration & sepsis

NEWS2: National Early Warning Score qSOFA: quick sepsis screen (with the caveat)Glasgow Coma Scale

Trauma & imaging rules

Canadian CT Head Rule: minor head injury NEXUS criteria: cervical spine imaging Canadian C-Spine Rule Ottawa ankle and foot rules Ottawa knee rule NEXUS Chest CT: blunt chest trauma

Toxicology

Paracetamol (acetaminophen) overdose: treatment line check

Hepatology & GI

MELD 3.0 (and MELD-Na): liver disease severity Child-Pugh: cirrhosis class Glasgow-Blatchford score: upper GI bleed FIB-4: liver fibrosis risk BISAP: acute pancreatitis severity Alvarado score: appendicitis

Oncology & dosing

Body surface area: Mosteller and Du Bois Carboplatin dose: Calvert formula Ideal, adjusted and lean body weight Corticosteroid equivalence Opioid dose equivalence (oral morphine as the reference)

Fluids & paediatrics

Burns resuscitation: Parkland (and the current lower start)Burn size: palm method (small or patchy burns)Paediatric maintenance fluids: Holliday-Segar (4-2-1)Paediatric weight estimate and emergency doses (APLS)Body mass index

Neuro & psych scales

PHQ-9: depression severity GAD-7: anxiety severity 4AT: delirium screen

Haematology

Reticulocyte production index Mentzer index: iron deficiency vs thalassaemia trait

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