Reference Manual

CALCULATIONS

Adjusted Calcium (mg/dL), only to Albumins <4.0 g/dL
Calculation Total Calcium+0.8 x [4.0-Albumin]
Included In Adjusted Calcium Phosphorus Product

Comprehensive Metabolic Panel

Comprehensive Metabolic Panel w/Phosphorus
Note Calculation provided only when Albumin is<4.0g/dL

Adjusted Calcium Phosphorus Product (mg2/dL2), only to Albumins <4.0g/dL
Calculation [Total Calcium (mg/dL)+0.8x{4.0-Albumin(g/dL)}] x Phosphorus
Included In Adjusted Calcium Phosphorus Product

Comprehensive Metabolic Panel 24 hours
Note Calculation provided only when Albumin is<4.0g/dL

A/G Ratio
Calculation Albumin/Globulin
Included In Comprehensive Metabolic Panel

Comprehensive Metabolic Panel w/Phosphorus

Anion GAP (mEq/L)
Calculation Sodium – (Chloride + CO2)
Included In Basic Metabolic Panel

Comprehensive Metabolic Panel

Comprehensive Metabolic Panel w/ Phosphorus

Electrolytes

Renal Function Panel
 

Body Surface Area (m2)
Calculation Adult (>= 16 years) uses DuBois and DuBois formula

  • BSA (m2) = 0.007184 x Wt 0.425 x Ht 0.725

Pediatric (< 16 years) uses Haycock formula

  • BSA (m2) = 0.024265 x Wt 0.5378x Ht 0.3964 where weight (Wt) is in kilograms and height (Ht) is in centimeters
Included In Urine Creatinine Clearance

Calcium Phosphorus Product (mg2/dL2)
Calculation Total Calcium x Phosphorus
Included In Calcium Phosphorus Product

Adjusted Calcium Phosphorus Product

Comprehensive Metabolic Panel w/Phosphorus

Cholesterol/HDL Ratio
Calculation Cholesterol/HDL
Included In Lipid Panel (Coronary Risk Profile)

Corrected Creatinine, 0 Hour, 2 Hour, 4 Hour (mg/dL)
Calculation Creatinine at 0 or 2 or 4 Hour Dwell–(Glucose at 0 or 2 or 4 Hour Dwellx0.00010386)
Included In PET, Standard

PET, Fast – 4 Hour only

Corrected Creatinine, 24 Hour (mg/dL)
Calculation Creatinine at 24 Hour Dwell–(Glucose at 24 Hour Dwellx0.00010386)
Included In PD Adequacy

Fluid, 24 Hour Dwell

Corrected Creatinine, Overnight (mg/dL)
Calculation Creatinine Overnight Dwell–(Glucose Overnight Dwellx0.00010386)
Included In Fluid, Overnight Dwell

Corrected Creatinine D/P, 0 Hour
Calculation Corrected Creatinine at 0 Hour Dwell/Plasma Creatinine at 2 Hour Dwell
Included In PET, Standard

Corrected Creatinine D/P, 2 Hour
Calculation Corrected Creatinine at 2 Hour Dwell/Plasma Creatinine at 2 Hour Dwell
Included In PET, Standard

Corrected Creatinine D/P, 4Hour
Calculation Corrected Creatinine at 4 Hour Dwell/Plasma Creatinine at 2 Hour Dwell
Included In PET, Standard

PET, Fast

Creatinine Clearance, Urine (Residual Renal Creatinine Clearance)
Calculation
Included Urine Creatinine Clearance
Note Where Wt is Dry Weight in kg and Ht is Height in cm.

Creatinine Reduction Ratio
Calculation [1– (Post Creatinine/Pre Creatinine)]x100
Included In Post BUN w/URR, CRR

Post BUN w/URR, Kt/V

GFR (mL/min/1.73 m2) (IDMS-Traceable Modification of Diet in Renal Disease (MDRD)
Calculation 175x(Scr)-1.154x (age)-0.203x(0.742 if female)x(1.210 if African American)
Included In GFR (CKD, Non Dialysis)

Globulin (g/dL)
Calculation Total Protein–Albumin
Included In Comprehensive Metabolic Panel

Comprehensive Metabolic Panel w/Phosphorus

Glucose D/DO, 2 Hour
Calculation Glucose at 2 Hour Dwell/Glucose at 0 Hour Dwell
Included In PET, Standard

Glucose D/DO, 4 Hour
Calculation Glucose at 4 Hour Dwell/Glucose at 0 Hour Dwell
Included In PET, Standard

Hemoglobinx3 (g/dL)
Calculation Hemoglobinx3
Included In Complete Blood Count (CBC) & Differential

Complete Blood Count (CBC) & Differential w/Reticulocytes

Hemoglobin

Hemoglobin & Hematocrit

Hemogram (Complete Blood Count w/o Differential)

Residual Urea Clearance, KrU – for Hemodialysis only
KrU (mL/min)
Calculation
Urine Urea Nitrogen x Urine Volume (mL)
Blood BUN x 0.9 x Total Urine Collection Time (min)
Kt/V Residual
Calculation
Urine Urea Nitrogen x Urine Volume (mL) x 10.08
Blood BUN Urine Collection Time (min) VSA
Volume from Surface Area (Liters)
Calculation
Adult (≥16 years) uses Hume and Weyers formula 
Male: V= -14.012934 + 0.296785 x Wt + 0.194786 x Ht
Female: V = -35.270121 + 0.183809 x Wt + 0.344547 x Ht
Pediatric (<16 years) uses Friis-Hansen formula
V = 0.135 x Wt^0.666 x Ht^0.535
where weight (Wt) is in kilograms and height (Ht) is in centimeters
Included In Residual Urea Clearance (KrU)

Kt/V Equilibrated
Calculation (0.924 x lnKt/V) – ((0.395 x lnKt/V) / (Min / 60)) + 0.056

(Leypoldt Formula)
Included In Kt/V Standard, URR
Kt/V Standard, Natural Log, URR
Note For patient dialyzing 2 or 4-6 times per week

For Kt/V Standard calculation purposes only, not reported

Kt/V Jindal
Calculation (0.04 x ((Pre BUN – Post BUN) / Pre BUN x 100) – 1.2)

(Jindal Formula)
Included In Kt/V Jindal (Not K/DOQI Recommended)
Note The HD Adequacy Work Group feels this formula should not be used to measure delivered dose of Hemodialysis. (K/DOQI Clinical Practice Guidelines for Hemodialysis Adequacy: Update 2000, Guideline 2)

Kt/V Natural Log
Calculation

(Daugirdas II Formula)
Included In Kt/V Natural Log, URR
Kt/V Natural Log, URR, nPNA
Kt/V Standard, Natural Log, URR
Note The K/DOQI recommendations are: Prescribed dose of hemodialysis: Kt/V of 1.3

Delivered dose of hemodialysis: Kt/V >1.2

Kt/V Standard
Calculation (168*(1-exp(-eqKt/V))/(Min/60))/((1-exp(-eqKt/V))/eqKt/V+(168/N/(Min/60))-1)

(Leypoldt Formula)
Included In Kt/V Standard, URR
Kt/V Standard, Natural Log, URR
Note For patient dialyzing 2 or 4-6 times per week

Low Density Lipoprotein (mg/dL)
Calculation Cholesterol–(Very Low Density Lipoprotein + HDL)
Included In Lipid Panel (Coronary Risk Profile)
 

nPNA, Hemodialysis
Calculation
Treatment #1

Beginning of week PNA (PCR) = Predialysis BUN /(36.3 + 5.48 x Kt/V Natural Log + 53.5/ Kt/V Natural Log) + 0.168
Treatment #2

Midweek PNA (PCR) = Predialysis BUN /(25.8 + 1.15 x Kt/V Natural Log + 56.4/ Kt/V Natural Log) + 0.168
Treatment #3

End of week PNA (PCR) = Predialysis BUN /(16.3 + 4.3 x Kt/V Natural Log + 56.6/ Kt/V Natural Log) + 0.168
Included In Kt/V Natural Log, URR, nPNA
Note nPNA calculation is only applicable to patients on thrice-weekly dialysis without significant residual function.  nPNA calculated from Kt/V without formal kinetic modeling according to Depner T and Daugirdas J:JASN 1996:7:780-785.

PD ADEQUACY CALCULATIONS
 

Weekly Total Kt/V
Calculation Weekly Residual Kt/V + Weekly Dialysate Kt/V
 

Weekly Residual Kt/V
Calculation ((Urine Urea Nitrogen/BUN) * (Urine Volume in mL/Urine Collection Time in minutes) * 10.08) / VSA
 

Weekly Dialysate Kt/V
Calculation ((Dialysate Urea Nitrogen/BUN) * (24 hour Dialysate Drain Volume in mL/1000) * 7) / VSA
 

Weekly Total Creatinine Clearance (Liters/week/1.73 m2)
Calculation Weekly Residual GFR + Weekly Dialysate Creatinine Clearance
 

Weekly Residual GFR (Liters/week/1.73 m2)
Calculation Arithmetic Mean of Weekly Urea Clearance and Weekly Creatinine Clearance
  ((Urine Urea Nitrogen/BUN) * (Urine Volume in mL/Urine Collection Time in minutes) * 10.08) + (Urine Creatinine/Plasma Creatinine * Urine Volume in mL/Urine Collection Time in minutes * 10.08))/2*1.73/BSA

Weekly Dialysate Creatinine Clearance (Liters/week/1.73 m2)
Calculation (Dialysate Corrected Creatinine/Plasma Creatinine) * (24 hour Dialysate Drain Volume in mL/1000) * 7 * 1.73/BSA

Volume from Surface Area (Liters)
Calculation Adult (>= 16 years) uses Hume and Weyers formula
Male: V= -14.012934 + 0.296785 x Wt + 0.194786 x Ht
Female: V = -35.270121 + 0.183809 x Wt + 0.344547 x Ht
Pediatric (< 16 years) uses Friis-Hansen formula
V = 0.135 x Wt0.666 x Ht0.535
where weight (Wt) is in kilograms and height (Ht) is in centimeters

Protein Nitrogen Appearance (PNA)
Calculation

Prothrombin Time (Protime): INR
Calculation (PT Ratio)ISI

PT Ratio = (Patient PT/Mean Normal PT)ISI

Mean Normal PT = Geometric Mean

ISI = International Sensitivity Index
Included In Prothrombin Time (PT)

% Recirculation
Calculation
Included In Recirculation Study

Total Iron Binding Capacity (TIBC) (µg/dL)
Calculation Transferrin x 1.4
Included In Iron Status w/ Iron & Transferrin

% Transferrin Saturation
Calculation (Iron/(Transferrin x 1.4)) x 100
Included In Iron Status w/ Iron & Transferrin

Urea D/P, 0 Hour
Calculation Urea at 0 Hour Dwell/Urea at 2 Hour Dwell
Included In PET, Standard

Urea D/P, 2 Hour
Calculation Urea at 2 Hour Dwell/Urea at 2 Hour Dwell
Included In PET, Standard

Urea D/P, 4 Hour
Calculation Urea at 4 Hour Dwell/Urea at 2 Hour Dwell
Included In PET, Standard

Urea Reduction Ratio (%)
Calculation [1 – (Post BUN/Pre BUN)] x 100
Included In Kt/V Jindal (Not K/DOQI Recommended
Kt/V Natural Log, URR
Kt/V Standard, Equilibrated, URR

Urine Creatinine, 24 Hour (mg/24 hour)
Calculation (Urine Creatinine/100) xTotal Urine Volume in mL
Included In 24 Hour Urine Creatinine

Urine Urea Nitrogen, 24 Hour (g/24 hour)
Calculation [(Urine Urea Nitrogen in mg/dL/100) x Total Urine Volume in mL] / 1000
Included In 24 Hour Urine Urea Nitrogen

Very Low Density Lipoprotein (mg/dL)
Calculation Triglycerides/5*
Included In Lipid Panel(Coronary Risk Profile)

*  Only provided if Triglycerides are<400 mg/dL

 

Calculation