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Sodium Correction in Hyperglycemia Calculator

Sodium Correction in Hyperglycemia Explanation and Clinical Context Sodium correction in the setting of hyperglycemia is essential because elevated serum glucose increases plasma osmolality and shifts water from the intracellular compartment into the extracellular compartment. This movement dilutes serum sodium and leads to a factitious reduction in the measured value. Correcting sodium helps clinicians assess the tr

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SOFA (Sepsis Organ Failure Assessment) Calculator

SOFA (Sepsis-related Organ Failure Assessment): Explanation and Clinical Context The SOFA score quantifies the degree of dysfunction across six organ systems (respiratory, coagulation, hepatic, cardiovascular, neurologic, and renal) by assigning 0–4 points for each organ system, producing a total score ranging from 0 to 24. It was developed primarily as an objective tool to describe and track organ dysfunction in cri

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SOFA Score for Organ Dysfunction Calculator

SOFA Score for Organ Dysfunction Explanation and Clinical Context The Sequential Organ Failure Assessment score is a clinical tool that evaluates the severity of organ dysfunction across six major organ systems. These systems include respiration coagulation liver function cardiovascular status central nervous system and renal function. Each system receives a subscore between zero and four based on objective clinical

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SOLOIST-WHF Post-HF Benefit Index Calculator

SOLOIST-WHF Post-HF Benefit Index: Explanation and Clinical Context The SOLOIST-WHF (Sotagliflozin on Cardiovascular Events in Patients with Type 2 Diabetes and Worsening Heart Failure) trial was a landmark study evaluating the dual SGLT1/2 inhibitor sotagliflozin in patients recently hospitalized for acute decompensated heart failure, with or without reduced ejection fraction. This calculator estimates the relative

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sPESI (Simplified Pulmonary Embolism Severity Index) Calculator

sPESI (Simplified Pulmonary Embolism Severity Index): Explanation and Clinical Context The sPESI is a validated scoring tool designed to stratify the 30-day mortality risk of patients diagnosed with acute pulmonary embolism (PE). It simplifies the original PESI by including six clinical variables: age >80 years, history of cancer, history of chronic cardiopulmonary disease, heart rate >110 bpm, systolic blood pressur

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Spot Urine Sodium Response Score (SUNSS) Calculator

Spot Urine Sodium Response Score: Explanation and Clinical Context The Spot Urine Sodium Response Score (SUNSS) is a clinical tool designed to predict the likelihood of poor diuretic response in patients with acute decompensated heart failure (ADHF). It incorporates key variables that influence natriuretic response: age, systolic blood pressure, serum sodium, and spot urine sodium. Lower urine sodium indicates reduce

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SPRINT Trial Risk Stratification Calculator

SPRINT Trial Risk Stratification: Explanation and Clinical Context The SPRINT Trial (Systolic Blood Pressure Intervention Trial) risk stratification is a clinical tool designed to estimate the expected benefit and risk of intensive (<120 mmHg) versus standard (<140 mmHg) systolic blood pressure control in patients with hypertension. It incorporates age, chronic kidney disease (CKD) status, and estimated 10-year ASCVD

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ST2 Biomarker Risk Tier Calculator

ST2 Biomarker Risk Tier: Explanation and Clinical Context The soluble ST2 (sST2) is a member of the interleukin-1 receptor family and acts as a biomarker of myocardial stress and fibrosis. It is a strong prognostic marker in patients with heart failure and acute coronary syndromes, independently predicting mortality and heart failure readmission. Risk tiers are generally classified based on sST2 concentration: - <35

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STABLE Score (TEVAR Risk) Calculator

STABLE Score (TEVAR Risk): Explanation and Clinical Context STABLE Score is a validated tool to predict 30-day mortality in patients undergoing thoracic endovascular aortic repair (TEVAR) for acute complicated type B aortic dissection. It incorporates four key clinical factors: Shock at presentation, presence of Malperfusion, Age >70 years, and Previous Aortic Surgery. Each factor scores 1 point if present, and the t

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STAT Mortality Categories Calculator

STAT Mortality Categories: Explanation and Clinical Context The STAT Mortality Categories are a validated risk stratification tool designed to estimate perioperative mortality for pediatric and congenital cardiac surgery. Patients are categorized from STAT 1 (lowest risk) to STAT 5 (highest risk) based on the complexity of the surgical procedure. STAT 1 procedures have the lowest predicted mortality (~0.7–2%), wherea

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STAT Mortality Category (STS-EACTS) Calculator

STAT Mortality Categories (STS–EACTS): Explanation and clinical context The STAT (Society of Thoracic Surgeons – European Association for Cardio-Thoracic Surgery) Mortality Scores and Categories are an empirically derived, procedure-based stratification system for congenital and pediatric cardiac surgery. Each index operation is assigned a numeric STAT score (range ~0.1–5.0) derived from large STS/EACTS registry data

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STEMI Rapid Reperfusion Urgency Assessment Tool

Explanation and Clinical Context This tool supports bedside decisions about how urgent reperfusion should be in patients with suspected ST segment elevation myocardial infarction and which reperfusion strategy is most appropriate in a given clinical setting. It uses simple inputs that mirror key elements of the 2025 guideline for acute coronary syndromes including the type of hospital time from symptom onset to first

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Steroid Dose Conversion Calculator

This tool converts the dose of a selected glucocorticoid to the equivalent dose of another glucocorticoid based on established relative anti inflammatory potency. Steroid Dose Conversion Explanation and Clinical Context Glucocorticoids vary in anti inflammatory potency mineralocorticoid activity and biological half life so dose conversion is required to maintain therapeutic equivalence when switching agents. Hydrocor

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Steroid-Dependence Risk Score (Chronic or Recurrent Pericarditis)

Steroid-Dependence Risk Score for (Recurrent) Pericarditis: Explanation and Clinical Context This scoring tool is derived from a prognostic model of patients with recurrent pericarditis that included steroid-dependence among its key variables (age, sex, number of recurrences, etiology, heart rate, pericardial imaging, LVEF, colchicine use, steroid use, DMARD use). The intention is to stratify patients by risk of poor

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STOP-AF Risk Index Calculator

STOP-AF Risk Index: Explanation and Clinical Context The STOP-AF Risk Index is a proposed clinical risk stratification tool designed to estimate the likelihood of developing atrial fibrillation (AF) in patients without prior AF, based on key clinical and echocardiographic parameters (such as age, prior atrial arrhythmia episodes, left atrial diameter, and presence of sleep apnea). The aim is to identify higher‐risk i

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STOPDAPT-2 ACS Mortality Prediction Tool

: Explanation and Clinical Context The STOPDAPT-2 ACS trial evaluated an abbreviated dual antiplatelet therapy (DAPT) strategy (1–2 months followed by clopidogrel monotherapy) versus standard 12-month DAPT in patients with acute coronary syndrome undergoing successful percutaneous coronary intervention. Although the primary endpoint did not demonstrate non-inferiority for the abbreviated therapy regarding the composi

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STOPDAPT-2 Risk Subgroup Calculator

Age (years) Acute coronary syndrome (ACS) presentation? Select Yes No High-bleeding-risk (HBR) criteria met? Select Yes No Complex PCI (yes/no)? Select Yes No STOPDAPT-2 ACS Risk Subgroup Calculator: Explanation and Clinical Context The STOPDAPT-2 family of trials investigated the safety and efficacy of abbreviated dual antiplatelet therapy (DAPT) duration followed by P2Y12 inhibitor monotherapy versus standard 12-mo

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Stress Test versus Coronary CT Before Discharge Pathway Tool

Stress Test versus Coronary Computed Tomography Before Discharge Pathway Tool Explanation and Clinical Context In contemporary management of acute coronary syndromes the two thousand twenty five guideline from the American College of Cardiology and the American Heart Association notes that selected patients can safely undergo either noninvasive stress testing or coronary computed tomography angiography before hospita

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Stroke Prognostic Instrument II (SPI-II) Calculator

Stroke Prognostic Instrument II (SPI-II): Explanation and Clinical Context The Stroke Prognostic Instrument II (SPI-II) is a validated clinical scoring system designed to predict the risk of recurrent stroke or major vascular events (such as myocardial infarction or vascular death) in patients with a prior non-cardioembolic ischemic stroke. SPI-II was developed from the National Institute of Neurological Disorders an

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Stroke TIA Public Triage Tool (ABCD2 community adaptation)

: Explanation and Clinical Context The ABCD2 score estimates early stroke risk after a transient ischemic attack (TIA) based on five clinical variables: age ≥ 60 years (1), blood pressure ≥ 140/90 mmHg (1), clinical features (unilateral weakness 2; speech disturbance without weakness 1), symptom duration (≥ 60 minutes 2; 10–59 minutes 1), and diabetes (1). Total 0–7. Risk stratification: Low (0–3), Moderate (4–5), Hi

Formula reviewed

Stroke Volume (SV) Calculator

Stroke Volume: Explanation and Clinical Context Stroke volume represents the amount of blood ejected by the left ventricle during each cardiac contraction. The most accurate non invasive method for calculating stroke volume in clinical practice uses pulsed wave Doppler at the left ventricular outflow tract. The calculation requires the cross sectional area of the outflow tract and the velocity time integral of the sy

Formula reviewed

Stroke Volume Index (SVi) Calculator

Stroke Volume Index (SVi): Explanation and Clinical Context Stroke Volume Index is a hemodynamic parameter that describes the amount of blood ejected by the left ventricle during each cardiac contraction, adjusted to body surface area. This index refines the interpretation of stroke volume by incorporating patient size, making it a more accurate indicator of forward flow in individuals with significantly different bo

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Stroke Volume Index (SVi) for RV Failure Prediction Calculator

Stroke Volume Index (SVi) for RV Failure Prediction: Explanation and Clinical Context Stroke Volume Index (SVi) is a hemodynamic parameter that represents the stroke volume normalized to body surface area. It is calculated as cardiac output divided by heart rate and then indexed to BSA, providing a load-adjusted measure of cardiac performance. In the context of right ventricular (RV) failure prediction, SVi has been

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STRONG-HF Risk Framework Calculator

STRONG-HF Risk Framework — explanation and clinical context This calculator implements a transparent prototype points system that aggregates commonly reported prognostic features relevant to patients hospitalized for acute heart failure (age, hemodynamics at discharge, NT-proBNP, renal function, potassium, LVEF, recent HF hospitalization, and intensity of guideline-directed medical therapy achieved at discharge). It

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STS Adult Cardiac Surgery Risk Score Calculator

STS Adult Cardiac Surgery Risk Score: Explanation and Clinical Context The STS Adult Cardiac Surgery Risk Score provides an evidence-based estimation of perioperative mortality and morbidity in adults undergoing cardiac surgery. It incorporates patient-specific clinical variables such as age, sex, renal function, history of heart failure, previous cardiac surgery, and type of surgical procedure. The score is derived

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STS Congenital Risk Model (2023 estimator)

— explanation and clinical context The STS Congenital Heart Surgery Database (CHSD) mortality risk approach stratifies operative risk primarily by procedure complexity (the STAT mortality category) and then adjusts for multiple patient-level factors (age group, weight/low birthweight, prior cardiothoracic operations, genetic/chromosomal abnormalities, non-cardiac congenital anomalies, multiple preoperative risk facto

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STS Primary Mitral Valve Repair / Replacement Risk Calculator

STS Primary Mitral Valve Repair/Replacement Risk Calculator: Explanation and Clinical Context The STS Primary Mitral Valve Repair/Replacement Risk Calculator is a tool developed by The Society of Thoracic Surgeons to estimate the short-term (operative/30-day) risk associated with mitral valve repair or replacement surgeries for patients with primary mitral regurgitation (MR) and degenerative mitral etiology. This cal

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STS Risk Score (SAVR) Calculator

STS Risk Score (SAVR): Explanation and Clinical Context The STS Risk Score is a validated tool developed by the Society of Thoracic Surgeons to estimate the risk of operative mortality and major morbidity for patients undergoing surgical aortic valve replacement (SAVR). It incorporates patient demographics, comorbidities, laboratory values, and procedural factors to produce a probability of 30-day or in-hospital mort

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STS Score (Aortic or Mitral or Combined) Calculator

STS Score (Aortic/Mitral/Combined): Explanation and Clinical Context The Society of Thoracic Surgeons (STS) risk score is a validated tool to predict operative mortality and morbidity for patients undergoing cardiac surgery, including aortic valve replacement, mitral valve surgery, or combined procedures. The score incorporates multiple patient-specific variables such as age, sex, NYHA class, left ventricular ejectio

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STS-IE Surgical Risk Model Calculator

STS-IE Surgical Risk Model: Explanation and Clinical Context The STS-IE (Society of Thoracic Surgeons – Isolated Valve Surgery) Risk Model is a validated tool to predict postoperative mortality and major morbidity for patients undergoing isolated valve surgery. It uses patient-specific clinical variables including age, sex, previous cardiac surgery, NYHA functional class, left ventricular ejection fraction, diabetes,

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Sudden Cardiac Death (SCD) in Athletes Risk Calculator (Multivariate)

Sudden Cardiac Death (SCD) in Athletes: Explanation and Clinical Context This calculator integrates multivariate risk modifiers observed in athlete populations—sex, race, sport type—and major red flags such as exertional syncope, family history, abnormal ECG, and known cardiac disease. It stratifies clinical concern but does not predict absolute probability. For athletes with hypertrophic cardiomyopathy (HCM), the va

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SVS / ISCVS PAD Grading System Calculator

SVS/ISCVS Grading System for Peripheral Artery Disease: Explanation and Clinical Context The SVS/ISCVS grading system provides a standardized framework for assessing the severity of lower extremity peripheral artery disease (PAD), particularly in patients with critical limb ischemia (CLI). It incorporates key clinical parameters including rest pain, presence of ulceration, gangrene, and ankle-brachial index (ABI) val

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Swedish PAH Registry Risk Model Calculator

Swedish PAH Registry Risk Model: Explanation and Clinical Context The Swedish PAH Registry Risk Model is a validated prognostic tool for patients with pulmonary arterial hypertension (PAH), developed from the Swedish Pulmonary Arterial Hypertension Registry (SPAHR). It integrates six key clinical and hemodynamic variables: WHO Functional Class (FC), 6-Minute Walk Distance (6MWD), NT-proBNP, Right Atrial Pressure (RAP

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SYNTAX II Score (Men + Women) Calculator

About SYNTAX II Score: The SYNTAX II Score combines anatomical and clinical variables to estimate 4-year mortality and guide revascularization strategy between PCI and CABG in patients with complex coronary artery disease. It improves upon the original SYNTAX I Score by incorporating key clinical parameters including age, sex, LVEF, renal function, COPD, PAD, and clinical presentation. Clinical Interpretation: A lowe

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Systematic Coronary Risk Evaluation (SCORE) Calculator

Systematic Coronary Risk Evaluation (SCORE) is a tool designed to estimate the 10-year risk of fatal cardiovascular disease in individuals without prior cardiovascular events. It uses age, sex, systolic blood pressure, total cholesterol, and smoking status as inputs. SCORE helps clinicians in primary prevention to determine the need for lifestyle modifications or pharmacological interventions. Risk categories are cla

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Systemic Immune-Inflammation Index (SII) Calculator

Systemic Immune-Inflammation Index (SII): Explanation and Clinical Context The Systemic Immune-Inflammation Index (SII) is calculated as Platelets × Neutrophils / Lymphocytes, reflecting the balance between host immune and inflammatory status. Originally described by Hu et al., 2014, SII has been studied in oncology and cardiovascular settings as a prognostic marker. High SII values suggest elevated systemic inflamma

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Systemic Inflammation Response Index (SIRI) Calculator

Systemic Inflammation Response Index (SIRI): Explanation and Clinical Context SIRI is a novel biomarker that quantifies systemic inflammation by integrating neutrophil, monocyte, and lymphocyte counts. It is calculated as (Neutrophil count × Monocyte count) / Lymphocyte count. This index has been studied for prognostic value in cardiovascular diseases, oncology, and sepsis. A higher SIRI reflects a greater inflammato

Formula reviewed

Systemic Vascular Resistance (SVR) Calculator

Systemic Vascular Resistance (SVR): Comprehensive Explanation and Clinical Context SVR represents the resistance encountered by blood as it flows through the systemic circulation. It reflects the interaction between vascular tone, blood viscosity, and vessel diameter. The calculation of SVR is derived from the relationship between perfusion pressure and cardiac output, expressed as the difference between mean arteria

Formula reviewed

Systemic Vascular Resistance Index (SVRi) Calculator

Systemic Vascular Resistance Index (SVRi): Explanation and Clinical Context The systemic vascular resistance index represents the afterload imposed on the left ventricle after correcting for body surface area. It is derived from the transpulmonary pressure gradient, represented by mean arterial pressure minus right atrial pressure, divided by the cardiac index. SVRi provides a more individualized assessment of vascul

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Systolic Pressure Recovery Index (Post-PE Healing) Calculator

Systolic Pressure Recovery Index (Post-Pulmonary Embolism Healing): Explanation and Clinical Context The Systolic Pressure Recovery Index (SPRI) is a hemodynamic ratio used to evaluate right ventricular and pulmonary arterial recovery after acute pulmonary embolism (PE). It quantifies the degree of pressure normalization across the pulmonary circulation, specifically reflecting how systolic and diastolic pressures re