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Clinical Calculators & Medical Scores

Guideline-based bedside calculators for clinicians. Free, mobile-friendly, computed locally — no data uploaded.

Anesthesiology

👄 Mallampati

Predict difficult intubation from oropharyngeal view.

🛏️ Aldrete

Readiness for discharge from post-anaesthesia recovery.

Cardiology

Estimate mean arterial pressure from systolic and diastolic blood pressure.

Heart-rate–corrected QT interval.

Major-bleeding risk on anticoagulation in atrial fibrillation.

Risk of major adverse cardiac events in ED chest pain.

Calculate LDL cholesterol from a lipid panel (Friedewald).

🫀 CHA₂DS₂-VASc

Annual stroke risk in non-valvular atrial fibrillation.

Peri-operative major cardiac risk in noncardiac surgery.

14-day risk of death, MI or urgent revascularisation in UA/NSTEMI.

❤️ Sgarbossa

Detect acute MI in the presence of LBBB or ventricular pacing.

Estimate myocardial oxygen demand (HR × systolic BP).

❤️ Pulse pressure

Difference between systolic and diastolic pressure.

Atherogenic cholesterol ratios (I: TC/HDL, II: LDL/HDL).

Surrogate for insulin resistance and atherogenic dyslipidaemia.

🫀 LDL (calc)

Calculate LDL cholesterol from a standard lipid panel.

Symptomatic functional classification of heart failure.

Heart-failure severity and prognosis in acute myocardial infarction.

ECG voltage criteria for left ventricular hypertrophy.

Prognostic score from exercise ECG (Bruce protocol).

Estimate major bleeding risk on anticoagulation in atrial fibrillation.

Predict major haemorrhage risk on warfarin in atrial fibrillation.

Risk-stratify chest pain in the emergency department for major adverse cardiac events.

Estimate the probability of heart failure with preserved ejection fraction.

❤️ TIMI STEMI

Predict 30-day mortality in ST-elevation myocardial infarction.

Weigh benefit vs bleeding risk of prolonged dual antiplatelet therapy after PCI.

Estimate likelihood that chest pain is due to coronary artery disease in primary care.

Risk-stratify possible cardiac chest pain (Emergency Department Assessment of Chest Pain Score).

Critical care

Quick SOFA for risk of poor outcome in suspected infection.

Aggregate early-warning score for acute deterioration (SpO2 scale 1).

Systemic inflammatory response syndrome criteria (≥ 2 positive).

Grade organ dysfunction in critically ill patients (6 systems, 0–4 each).

Oxygenation severity in ventilated patients (esp. paediatric ARDS).

Predict success of high-flow nasal cannula in acute hypoxaemic respiratory failure.

Full Outline of UnResponsiveness — coma scale usable in intubated patients.

Grade agitation and sedation depth in the ICU.

Bedside physiological score to detect clinical deterioration.

Total oxygen carried per 100 mL of arterial blood.

Rate of oxygen delivery to tissues.

Afterload estimate from haemodynamic measurements.

🔪 Surgical Apgar

Predict major postoperative complications and death from intraoperative data.

🤢 Apfel PONV

Predict postoperative nausea and vomiting risk.

Support diagnosis of ventilator-associated pneumonia.

Predict non-invasive ventilation failure in hypoxaemic respiratory failure.

🧪 Compensation

Given a primary acid-base disorder, computes the expected compensation; deviation suggests a second disorder.

🧂 Corrected Na

Hyperglycemia dilutionally lowers measured sodium; correct sodium for glucose (Katz and Hillier).

RSBI = respiratory rate ÷ tidal volume (L); < 105 predicts successful weaning/extubation (Yang-Tobin).

Seven items estimating the risk of postoperative pulmonary complications in non-cardiac surgery (low/intermediate/high).

Emergency

24-hour crystalloid resuscitation volume for major burns.

Likelihood of acute appendicitis (MANTRELS).

📉 Shock Index

Heart rate divided by systolic BP — a marker of haemodynamic instability.

🦶 Ottawa Ankle

Decide whether ankle/foot X-rays are needed after injury.

🦵 Ottawa Knee

Decide whether a knee X-ray is needed after acute injury.

Whether CT is needed after minor head injury (GCS 13–15).

Determine whether cervical-spine imaging can be safely deferred after trauma.

🦴 Canadian C-spine

Stepwise rule for cervical-spine imaging in alert, stable trauma patients.

Recognition of stroke in the emergency room.

🫀 SF Syncope

Identify syncope patients at risk of a serious 7-day outcome (CHESS).

Lab-based risk indicator for necrotising soft-tissue infection.

Estimate likelihood of group A streptococcal pharyngitis.

Screen for acute aortic syndrome across three feature categories.

Predict the likelihood of an uncomplicated ureteral stone in acute flank pain.

Physiologic trauma severity score for triage and outcome prediction.

Predict need for massive transfusion in trauma.

Predict 30-day serious adverse events after emergency department syncope.

🔥 Revised Baux

Estimate mortality risk after major burns.

Seven weighted parameters (sex/SBP/HR/Hb/base excess/FAST/complex fracture) predicting the probability of massive transfusion in severe trauma (0–28).

🔥 Rule of Nines

Estimate adult burn total body surface area (% TBSA, Wallace rule of nines) for resuscitation and referral decisions.

🩸 ATLS shock

Classify ATLS hemorrhagic shock (I–IV) from vital signs and mental status/urine output, with resuscitation direction.

Eight perioperative parameters predicting mortality in secondary peritonitis (Mannheim Peritonitis Index).

Estimate burn severity and survival probability from sex, age, inhalation injury, full-thickness burn and %TBSA.

Endocrinology

Estimate insulin resistance from fasting glucose and insulin.

🦋 Burch-Wartofsky

Likelihood of thyroid storm in thyrotoxicosis.

Estimate the average glucose of the past 2–3 months from HbA1c (ADAG formula).

Gastroenterology

Risk of needing intervention in upper GI bleeding; identifies low-risk patients.

Rebleeding and mortality risk after upper GI bleeding (complete score).

Severity and mortality risk in acute pancreatitis (non-gallstone).

Early mortality risk in acute pancreatitis (within 24 h).

Severity of acute pancreatitis (PANCREAS criteria, at 48 h).

Endoscopic stigmata of peptic ulcer bleeding and rebleed risk.

Cleveland Clinic faecal incontinence severity score.

Classify stool form as a marker of transit time.

Predict in-hospital mortality in acute upper gastrointestinal bleeding.

Predict mortality and morbidity in perforated peptic ulcer.

Upper GI bleed risk score predicting need for intervention (transfusion, endoscopy, surgery).

Compute the acute pancreatitis CT severity index from the Balthazar CT grade and extent of necrosis (0–10).

General

Calculate body mass index from weight and height, with WHO weight-status category.

Estimate body surface area (Mosteller formula) for dosing.

Ideal body weight and adjusted body weight for dosing.

Central adiposity and cardiometabolic risk indicator.

Surrogate marker of insulin resistance.

Comorbidity burden and 10-year survival estimate.

10-year risk of developing type 2 diabetes.

Estimate pancreatic beta-cell function from fasting glucose and insulin.

Quantitative insulin-sensitivity check index.

Hematology

Pre-test probability of deep vein thrombosis.

Pre-test probability of pulmonary embolism.

Rule out PE in low-risk patients without D-dimer (all 8 negative).

VTE risk in hospitalised medical patients.

Differentiate iron deficiency from thalassaemia trait in microcytosis.

Calculate ANC to grade neutropenia and infection risk.

Clinical pre-test probability of pulmonary embolism (objective, revised Geneva).

🦵 IMPROVE VTE

VTE risk in hospitalised medical patients (IMPROVE model).

Risk-stratify acute PE for 30-day mortality (simplified PESI).

30-day mortality class in acute PE (original PESI).

🩸 Iron deficit

Calculate total iron deficit for replacement.

Assess iron status from serum iron and TIBC.

Pre-test probability of HIT.

An inflammatory and prognostic marker from the differential.

Composite inflammatory marker (platelet × neutrophil / lymphocyte).

Assess the marrow response to anaemia (corrected reticulocyte count).

Pre-test probability of heparin-induced thrombocytopenia (HIT).

Diagnose overt disseminated intravascular coagulation.

Probability of severe ADAMTS13 deficiency (TTP) in thrombotic microangiopathy.

Stratify 30-day risk in normotensive (non-high-risk) pulmonary embolism.

Decide eligibility for outpatient management of pulmonary embolism.

Venous thromboembolism risk stratification for surgical inpatients (2005 version) to guide prophylaxis.

Hepatology

🫀 Child-Pugh

Grade severity of chronic liver disease (Class A/B/C).

Model for End-stage Liver Disease with sodium (UNOS).

Non-invasive estimate of advanced hepatic fibrosis.

🫀 Maddrey DF

Severity of alcoholic hepatitis and steroid decision threshold.

Prognosis in alcoholic hepatitis to guide corticosteroid use.

Non-invasive marker of hepatic fibrosis/cirrhosis.

Predict advanced fibrosis in non-alcoholic fatty liver disease.

Determine whether ascites is due to portal hypertension.

🫀 West Haven

Grade the severity of hepatic encephalopathy.

Predict response to corticosteroids at day 7 of treatment.

Latest MELD for end-stage liver disease, adding sex, albumin and interaction terms.

Determine whether hepatocellular carcinoma meets the Milan criteria — the classic morphologic standard for liver transplant candidacy.

Infectious disease

Likelihood of group A streptococcal pharyngitis.

Estimate likelihood of streptococcal sore throat to guide antibiotics.

Severity-of-illness score for patients with bacteraemia.

Nephrology

Serum anion gap with optional albumin correction.

Estimate creatinine clearance for renal drug dosing.

Estimated GFR by the race-free CKD-EPI 2021 creatinine equation.

Differentiate pre-renal from intrinsic acute kidney injury.

Expected PaCO₂ for a metabolic acidosis.

Calculated serum osmolality and reference for osmolal gap.

Assess renal potassium handling in dyskalaemia.

🧪 Delta ratio

Detect a mixed metabolic acid–base disorder.

💧 Water deficit

Estimate the free water deficit in hypernatraemia.

Assess urinary ammonium in normal-anion-gap metabolic acidosis.

🧪 Corrected Na

Adjust measured sodium for the dilutional effect of high glucose.

🧪 Na deficit

Estimate the sodium deficit to plan correction in hyponatraemia.

Differentiate pre-renal AKI from ATN, useful after diuretics.

🦴 Corrected Ca

Adjust total calcium for low albumin.

🧪 Corrected AG

Adjust the anion gap for hypoalbuminaemia.

🧪 HCO₃ deficit

Estimate the bicarbonate deficit in metabolic acidosis.

🦴 Ca × PO₄

Product of calcium and phosphate, relevant to vascular calcification risk.

Predict contrast-induced acute kidney injury risk after PCI.

Neurology

Score consciousness from eye, verbal and motor responses (3–15).

Short-term stroke risk after a transient ischaemic attack.

Quantify neurological deficit severity in acute stroke (0–42).

Global disability/dependence after stroke.

Brief screen for cognitive impairment.

30-day mortality risk after intracerebral haemorrhage.

Clinical severity grading of aneurysmal SAH.

GCS-based grading of aneurysmal SAH.

🧠 Mod. Fisher

CT-based vasospasm risk after subarachnoid haemorrhage.

Pre-hospital screen for large-vessel occlusion.

Field assessment for large-vessel occlusion stroke.

Combine Glasgow Coma Scale with pupil reactivity for finer prognostication.

🩻 Carotid stenosis

Compute extracranial ICA stenosis from diameters (NASCET, optional ECST) with grade and management direction.

🩻 Intracranial stenosis

Compute intracranial arterial stenosis from diameters (WASID method) with grade and management direction (distinct from extracranial NASCET).

Estimates the 5-year rupture risk of an unruptured intracranial aneurysm from population, hypertension, age, size, prior SAH and site.

Estimates the 3/5-year growth risk of an unruptured intracranial aneurysm from prior SAH, location, age, population, size and shape.

Surgical risk grade for brain arteriovenous malformation, summing size, eloquence and venous drainage (grade 1–5).

Obstetrics

Readiness of the cervix for labour induction.

🤰 CRL → GA

Estimate first-trimester gestational age from crown-rump length using the Robinson formula.

Oncology

Functional status grading used in oncology.

Functional status on a 0–100 scale.

Predict venous thromboembolism risk in ambulatory cancer patients on chemotherapy.

Identify low-risk febrile neutropenia suitable for outpatient management.

Prognosis in aggressive non-Hodgkin lymphoma.

Prognosis in follicular lymphoma.

Inflammation-based prognostic score in cancer.

Nutrition/immune index predicting surgical and oncologic outcomes.

RMI = ultrasound score U × menopausal status M × CA-125; a cut-off of 200 separates benign from malignant and guides gynecologic-oncology referral.

🎗️ GTN score

Sum of 8 prognostic factors for gestational trophoblastic neoplasia; ≤ 6 low risk (single-agent chemo), ≥ 7 high risk (combination chemo).

Pediatrics

Rapid assessment of newborn condition at 1 and 5 minutes.

💧 Maint. fluids

Daily and hourly maintenance fluid requirements by weight.

🫘 Schwartz eGFR

Bedside paediatric estimated GFR from height and creatinine.

👶 Corrected age

Adjust chronological age for prematurity.

Differentiate septic arthritis from transient synovitis in a child's hip.

👶 Westley Croup

Grade croup severity in children.

Assess likelihood of appendicitis in children.

Grade respiratory distress in the newborn (0 = no distress).

Assess neonatal respiratory distress severity.

Assess procedural pain in neonates and young infants.

Decision rule for head CT in minor head trauma (GCS 14–15) in children ≤ 18 y, with separate < 2 y and ≥ 2 y pathways.

Brighton PEWS: behaviour/cardiovascular/respiratory each 0–3 (+ continuous nebs and post-op vomiting +2 each) to detect clinical deterioration in children.

🧒 Pediatric GCS

Modified infant/child GCS: eye (4) + verbal (5) + motor (6), total 3–15, to assess level of consciousness.

Five signs (suprasternal retraction, scalene contraction, air entry, wheezing, oxygen saturation) totaling 0–12 to grade pediatric acute asthma severity.

🧒 Pediatric ETT

Estimate pediatric endotracheal tube internal diameter (uncuffed/cuffed) and insertion depth by age (~ 1–10 y; infants by weight).

Estimate neonatal gestational age from neuromuscular and physical maturity subtotals (GA = 24 + 0.4 × total).

🚨 Peds code card

Weight-based PALS emergency drugs and electrical therapy doses (epinephrine/amiodarone/adenosine/atropine/defibrillation/fluids, etc.).

Pharmacology

💊 Corr. phenytoin

Adjust total phenytoin level for low albumin (Sheiner-Tozer).

Adjusted body weight for drug dosing in obesity.

Estimate lean body mass for dosing and physiology.

💊 Opioid equiv

Convert daily opioid doses between agents via oral morphine equivalents (OME), with an incomplete cross-tolerance reduction range.

💊 Benzo equiv

Convert between benzodiazepines by diazepam equivalents, for switching and tapering (long-acting substitution for short-acting agents).

💉 Vancomycin

Empiric vancomycin loading dose, maintenance dose and interval by weight and creatinine clearance (AUC-guided; requires TDM).

💊 APAP safety

Check acetaminophen daily/single-dose limits and whether an acute ingestion reaches the toxic threshold or warrants NAC.

💉 Aminoglycoside

Gentamicin/tobramycin/amikacin high-dose extended-interval (once-daily) empiric dosing by dosing weight and CrCl; requires TDM.

🫘 Renal adjust

Quick reference for adjusting common renally-cleared drugs by renal function (CrCl/eGFR); not exhaustive — follow the latest product label.

Quick reference to high-risk drug classes, risk factors and management for QT prolongation / torsades (TdP); per-drug authoritative ratings at CredibleMeds.

🤰 Pregnancy meds

The former FDA letter categories (withdrawn 2015), the PLLR labelling rule, prescribing principles and authoritative resources; not a per-drug rating.

🎯 TDM targets

Quick reference to target ranges, sampling timing and toxicity cues for commonly monitored drugs.

🫀 Hepatic adjust

Adjustment and avoidance points for common drugs in hepatic impairment (Child-Pugh), by class; follow the product label.

🔗 DDI key points

Quick reference to mechanisms and typical combinations for high-frequency, dangerous drug interactions; check each pair in a professional interaction database.

🩸 Warfarin INR

Target INR, high-INR/bleeding management (ACCP/CHEST), interactions and missed-dose points.

Psychiatry

Screen and grade generalised anxiety severity.

Brief screen for problem drinking.

Three-item screen for hazardous drinking.

Bedside screen for delirium.

Grade alcohol withdrawal severity to guide symptom-triggered treatment.

Grade opioid withdrawal severity (Clinical Opiate Withdrawal Scale).

Two-item screen for depression over the last 2 weeks.

Respiratory

Community-acquired pneumonia severity and disposition.

🫁 A–a gradient

Alveolar–arterial oxygen gradient (room air, sea level by default).

🚬 Pack-years

Cumulative cigarette exposure for screening and risk.

Oxygenation index for ARDS severity (Berlin definition).

Quantify daytime sleepiness across eight everyday situations.

Screen for obstructive sleep apnoea risk.

Classify a pleural effusion as exudate or transudate.

Multidimensional prognosis in COPD.

In-hospital mortality risk in acute COPD exacerbation.

Predict need for intensive respiratory or vasopressor support in CAP.

Grade breathlessness in chronic respiratory disease.

Pneumonia severity without laboratory tests (community setting).

Health-status impact of COPD across 8 items.

Assess asthma control over the past 4 weeks.

Rheumatology

Disease activity score over 28 joints (ESR-based).

Lab-free, immediately available rheumatoid arthritis disease activity index.