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Medical Equations   Click a letter to jump to that section. Click on a link below to use a formula or criteria.   A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z     A A-a Gradient a/A Ratio AaPO2 Correction for FIO2 Absolute Lymphocyte Count Absolute Neutrophil Count Absolute Reticulocyte Count Allowable Blood Loss Amikacin Dosing q24hr (also Kanamycin and Streptomycin) Amikacin Dosing to Produce Desired Peak and Trough Levels Amikacin Level Prediction from Maintenance Dosing Amikacin Steady State Dosage Adjustment Aminoglycoside Clearance Estimate Amortization of Student Loans Anion Gap Delta Delta Gradient Multicalc® Anion Gap Delta Delta Ratio Multicalc® Anion Gap in Hypoalbumin States Anion Gap Area Unit Conversions Ascites Albumin Gradient AUC Dose Calculation for Carboplatin (Calvert formula)     B Basic Unit Conversions Bayesian Statistics I MultiCalc® Bayesian Statistics II MultiCalc® Benefit Increase / Number Needed to Treat Multicalc® Benzodiazepine Dosing Conversions Bicarbonate Deficit Blood Pressure Percentiles for Boys (2 - 17 years) Blood Pressure Percentiles for Girls (2 - 17 years) Body Mass Index (Quetelet's index) Body Mass Index Percentiles for Boys (2 - 20 years) Body Mass Index Percentiles for Girls (2 - 20 years) Body Surface Area (Du Bois Method) Body Surface Area (Mosteller, square root method) Burn Injury Fluid Resuscitation (Brooke estimate) Burn Injury Fluid Resuscitation (Demling dextran estimate) Burn Injury Fluid Resuscitation (Evans estimate) Burn Injury Fluid Resuscitation (Modified Brooke crystalloid estimate) Burn Injury Fluid Resuscitation (Parkland crystalloid estimate) Burn Injury Fluid Resuscitation (Slater estimate)     C Calcium Correction in Hypoalbuminemia (SI units) Calcium Correction in Hypoalbuminemia Carbon Dioxide Production Cardiac Output MultiCalc® Cardiac Output Chi Square Analysis Closing Capacity to Total Lung Volume Capacity Closing Capacity Closing Volume to Vital Capacity Ratio Comprehensive Unit Conversions Confidence Interval of a Binomial Proportion Confidence Interval of a Difference Between Proportions Confidence Interval of a Ratio of Proportions Confidence Interval of a Ratio of Ratios Confidence Interval of a Survey Corticosteroid Medication Dosing Conversions (glucocorticoid effect) Corticosteroid Medication Dosing Conversions (mineralocorticoid effect) Creatinine Clearance (measured) Creatinine Clearance (measured, SI units) Creatinine Clearance by Mass Creatinine Clearance Estimate by Cockcroft-Gault Equation (SI units) Creatinine Clearance Estimate by Cockcroft-Gault Equation Creatinine clearance estimate for changing serum creatinine Creatinine Kinetics Multicalc® CSF IgG Index CSF Protein Concentration Correction in Blood Contaminated CSF CSF WBC Correction in Blood Contaminated CSF     D Density Unit Conversions Digitalis Body Load Dose Adjustment for Body Surface Area Dose Driven IV-Drip Rate Calculator     E Energy Unit Conversions Epidural Formulation Compounding Calculator Epoprostenol (Flolan) Infusion Rate Calculator Estimated Blood Volume Estimated Date of Delivery (EDD) Pregnancy Calculator     F False Negative Rate from Sensitivity and Prevalence False Negative Ratio from Sensitivity and Prevalence False Positive Rate from Specificty and Prevalence False Positive Ratio from Specificity and Prevalence Fentanyl Patch Initial Dosing Estimate Based on Prior Narcotic Dosing Flow Unit Conversions Force Unit Conversions Fractional Excretion of Amylase (Amylase to creatinine clearance ratio) Fractional Excretion of Sodium (SI units) Fractional Excretion of Sodium Fractional Excretion of Urate Friedewald Equation for Low Density Lipoprotein (LDL) Friedewald Equation for Low Density Lipoprotein (LDL, SI units) Functional Residual Capacity     G Gentamicin Dosing q24hr Gentamycin Dosing to Produce Desired Peak and Trough Levels Gentamycin Level Prediction from Maintenance Dosing Gentamycin Steady State Dosage Adjustment Gestational Age from Estimated Date of Delivery (EDD) Glomerular Filtration Rate Estimate by Abbreviated MDRD Study Equation (SI units) Glomerular Filtration Rate Estimate by Abbreviated MDRD Study Equation Glomerular Filtration Rate Estimate by Quadratic Equation Glomerular Filtration Rate Estimate by Schwartz Formula Glomerular Filtration Rate Estimation using the MDRD Equation (SI units) Glomerular Filtration Rate Estimation using the MDRD Equation Gorlin Formula for Valve Area     H Harris-Benedict Estimation of Basal Energy Expenditure Height for Age Percentiles for Boys (2 - 20 years) Height for Age Percentiles for Girls (2 - 20 years) Hemoglobin A1C Estimation from Mean Plasma Glucose Hemoglobin A1C to Mean Plasma Glucose Estimation Henderson-Hasselbach Equation Hepatitis C Fibrosis Prediction Score HOMA Formula: Homeostasis Model Assessment of Insulin Resistance Housestaff Activity Index Hyponatremia Correction Infusate Rate     I Ideal Body Weight Percentage Ideal Body Weight IME Ajusted Ratio for Medical Education Medicare Payments to Teaching Hospitals In-Flight PaO2 Estimation (using PFT's) In-Flight PaO2 Estimation Infant Head Circumference for Age Percentiles (< 36 months) Infant Length for Age Percentiles (< 36 months) Infant Weight for Age Percentiles (< 36 months) Infant Weight for Length Percentiles (< 36 months) Inspiratory Capacity International Normalized Ratio of Prothrombin Time (INR) Iron Replacement (parenteral dosing) for Iron Deficiency IV Drip Maintenance Rate Calculator     K Kappa Measurement of Inter-observer Agreement MultiCalc® Kappa Measurement of Inter-observer Agreement: Bennett's Kappa Kappa Measurement of Inter-observer Agreement: Cohen's Kappa Kappa Measurement of Inter-observer Agreement: Scott's Kappa Kt/V Dialysis Dose Barth Formula Kt/V Dialysis Dose Basile Formula Kt/V Dialysis Dose Daugirdas Formula Kt/V Dialysis Dose Formulae MultiCalc® Kt/V Dialysis Dose Jindal Formula Kt/V Dialysis Dose Kerr Formula Kt/V Dialysis Dose Keshaviah Formula Kt/V Dialysis Dose Lowrie Formula     L Lean Body Weight (Female) Lean Body Weight (Male) Lean Body Weight Based on Creatinine Production Length Unit Conversions Likelihood Ratio MultiCalc® Likelihood Ratio of Negative from Raw Data Likelihood Ratio of Positive from Raw Data Lung Age Estimation for Smoking Cessation Counseling Lung Volume Multicalc®     M Maintenance Fluid Calculation for Children Mean Corpuscular Hemoglobin Concentration Mean Corpuscular Hemoglobin Mean Corpuscular Volume Mean Vascular Pressure (systemic or pulmonary) MELD Score for End-Stage Liver Disease (patients 12 or more years old) Mid-parental Target Height Prediction     N Nasal Canula Oxygen Fractional Inspired O2 (FIO2) Estimate Negative Predictive Value from Raw Data Negative Predictive Value of a Test Normal Range for Body Weight Number Needed to Harm (NNH) from Odds Ratio (OR) and Patient Expected Event Rate (PEER) Number Needed to Treat (NNT) from Odds Ratio (OR) and Patient Expected Event Rate (PEER)     O Odds from Probability Odds Ratio and Relative Risk Opioid Medication Dose Conversions Osmolal Gap Calculator (SI units) Osmolal Gap Calculator Osmolality Estimator (serum) Osmolar Clearance Overall Accuracy of a Test from Raw Data Overall Accuracy of a Test from Sensitivity, Specificity and Prevalence Oxygen Consumption Oxygen Content of Arterial Blood Oxygen Content of Venous Blood Oxygen Delivery Units Conversions Oxygenation Index (OI)     P paO2 / FIO2 Ratio (for MODS Calculation) PaO2 Correction for FIO2 Peak Expiratory Flow Prediction Peak Expiratory Flow Variability in Asthma PELD Score for End-Stage Liver Disease (patients less than 12 years old) PFT Adjusted Predicted Values for Men MultiCalc® PFT Adjusted Predicted Values for Women MultiCalc® PFT Predicted Values for Boys MultiCalc® PFT Predicted Values for Girls MultiCalc® PFT Predicted Values for Men MultiCalc® PFT Predicted Values for Women MultiCalc® Phenytoin Free (Unbound) Drug Level (Adjusted for Hypoalbuminemia) Phenytoin Total Drug Level (Adjusted for Hypoalbuminemia and Renal Function) Pneumothorax Degree of Collapse Positive Predictive Value from Raw Data Positive Predictive Value of a Test Post Test Odds from Pre Test Odds and Likelihood Ratio MultiCalc® Post Test Odds of a Negative from Raw Data Post Test Odds of a Negative Result from Sensitivity Specificity and Prevalence Post Test Odds of a Positive from Raw Data Post Test Odds of a Positive Result from Sensitivity Specificity and Prevalence Post Test Probability from Likelihood Ratios and Multiple Test Results Post Test Probability from Pre Test Probability, Sensitivity and Specificity Power Unit Conversions Pre Test Odds from Prevalence Pre Test Odds from Raw Data Pregnancy Gestation by LMP and Ultrasound Biometry Pressure Adjusted Heart Rate (For MODS calculation) Pressure Unit Conversions Prevalence of a Finding or Disease from Test Data Probability from Odds Protein Bound Calcium Protein Catabolic Rate (normalized PCR) Protein Catabolic Rate Pulmonary Vascular Resistance Pulse Pressure Variation (percentage)     Q QT Interval Correction (EKG) QUICKI Formula for Insulin Resistance     R Red Blood Cell Volume by Radionucleotide Dilution Renal Failure Index Residual Renal Function in Hemodialysis Patients (Kru) Residual Volume to Total Lung Capacity Ratio Respiratory Quotient Reticulocyte Production Index Right to Left Shunt Fraction Qs/Qt Risk Increase / Number Needed to Harm Multicalc® Risk Reduction / Number Needed to Treat Multicalc®     S Sensitivity of a Test Serum Sodium Concentration Change Considering Infused and Excreted Cations SI Unit Conversions: Body Fluid Chemistries SI Unit Conversions: Chemistry Values SI Unit Conversions: Coagulation Tests SI Unit Conversions: Drugs SI Unit Conversions: Hematology SI Unit Conversions: Urine Chemistry Values Sodium Change in Hyperlipidemeia Sodium Change in Hyperproteinemia Sodium Correction in Hyperglycemia Sodium Deficit in Hyponatremia Specificity of a Test Speed Unit Conversions Standard Drink Equivalents Stool Osmolal Gap Survey Sample Size with Population Correction Survey Sample Size Systemic Vascular Resistance Systolic Pressure Variation (percentage)     T Temperature Unit Conversions Textile Type Unit Conversions Time Averaged Concentration of Urea in Hemodialysis Time Unit Conversions TIPS Risk predictor / Survival predictor (Transjugular Intrahepatic Portosystemic Shunt) Tobramycin Dosing to Produce Desired Peak and Trough Levels Tobramycin Level Prediction from Maintenance Dosing Tobramycin Steady State Dosage Adjustment Total Body Water (BIA formula) Total Body Water Estimation Based on Weight Alone Total Body Water in Men (Humes-Weyer formula) Total Body Water in Men (Johansson formula) Total Body Water in Men (Lee formula) Total Body Water in Men (Watson formula) Total Body Water in Women (Humes-Weyer formula) Total Body Water in Women (Johansson formula) Total Body Water in Women (Lee formula) Total Body Water in Women (Watson formula) Total Daily Energy Requirement Estimate Total Lung Capacity Transferrin Saturation Transtubular Potassium Gradient at CCD True Negative Ratio from Specificity and Prevalence True Positive Ratio from Sensitivity and Prevalence     U Urea Reduction Percentage in Hemodialysis (PRU) Urea Reduction Ratio in Hemodialysis (URR) Urinary Protein Excretion Estimation     V Vancomycin Dosing to Produce Desired Peak and Trough Levels Vancomycin Level Prediction from Maintenance Dosing Vancomycin Steady State Dosage Adjustment Ventilation Index Very Low Density Lipoprotein (VLDL) Vital Capacity Volume of Distribution of Urea Volume Unit Conversions     W Water Deficit in Hypernatremia Weight Based Dosage Calculator Weight for Age Percentiles for Boys (2-20 years) Weight for Age Percentiles for Girls (2-20 years) Weight for Height Percentiles for Boys (77-121 cm tall) Weight for Height Percentiles for Girls (77-121 cm tall) Weight Unit Conversions WHO Assessment of Malnutrition in Boys 0 to 2 Years Old WHO Assessment of Malnutrition in Boys 2 to 5 years Old WHO Assessment of Malnutrition in Girls 0 to 2 Years Old WHO Assessment of Malnutrition in Girls 2 to 5 years Old Winter's Formula for Expected PCO2     Z Z Score to Percentile Estimation   Legal Notices and Disclaimer   All information contained in and produced by the MedCalc 3000 system is provided for educational purposes only. This information should not be used for the diagnosis or treatment of any health problem or disease. THIS INFORMATION IS NOT INTENDED TO REPLACE CLINICAL JUDGMENT OR GUIDE INDIVIDUAL PATIENT CARE IN ANY MANNER. Click here for full notice and disclaimer.   MedCalc 3000 is Copyright © 1998-2008 Foundation Internet Services, LLC    [Build 237221 v8.9]