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## Advanced Pharmacokinetic Dosing AUC Calculator

For Vancomycin AUC related dosing only, please use the following Calculator >>       Help support the site.  We still have the holiday subscription pricing option (\$49.95 for one year).  Faster loading. Ad-Free. Superior navigation.
Patient: Location:
Age: Sex: Serum Creatinine:
Height
: Weight:

Clearance method
:

Desired Peak
: mcg/ml   Desired Trough: mcg/ml

Volume of distribution:  L/kg
Usual range: aminoglycosides: 0.25 - 0.35.   Vanco: 0.65 - 0.9

## Optional section:

Select elimination rate constant (Ke) calculation method: Info
(VANCOMYCIN)
:
Ke = 0.00083 x CRCL + 0.0044 Usual Vd reported: 0.9 L/kg. (0.7 - 0.9 L/kg) Ref: 3,4,5
Clearance method: CL (L/hr) = CrCl (ml/min) x 0.06. Ke = Vanco CL/Vd. Usual Vd: 0.7L/kg. Ref: 6
Ke (hr-1) = [(0.695[(CrCl mL/min)/TBW kg] + 0.05) x 0.06] / Vd factor ] Usual Vd: 0.7L/kg. Ref: 2

New option based on input from clinicians - general assumption, adjusted body weight may be used in the morbidly obese patients receiving vancomycin: Historically actual or total is used in all cases.
Use Adjusted body weight or Use Actual (total) weight for vanco dosing.

(Aminoglycosides)
:
Clearance method: CL (L/hr) = CrCl (ml/min) x 0.06. Ke = CL/Vd. Ref: 5,6
Ke = 0.00293(CrCl) + 0.014 Ref: 1,4
Ke (hr-1) = (0.0024 x CrCl) + 0.01 Ref: 5

Amputations

This latest version is based on a comprehensive review of the most recent pharmacokinetic textbooks. Some of the sources used are listed here
1. Bauer LA. The Aminoglycoside Antibiotics. In Bauer LA, ed. Applied Clinical Pharmacokinetics. 2nd ed. New York, NY: McGraw Hill Medical; 2008:97-206.

2. Bauer LA. Vancomycin. In Bauer LA, ed. Applied Clinical Pharmacokinetics. 2nd ed. New York, NY: McGraw Hill Medical; 2008:207-298.

3. Burton ME, Shaw LM, Schentag JJ, Evans WE. Applied Pharmacokinetics & Pharmacodynamics: Principles of Therapeutic Drug Monitoring. 4th ed. Philadelphia: Lippincott Williams & Wilkins; 2006.

4. DiPiro JT, Spruill WJ, Wade WE, Blouin RA, Pruemer JM. Concepts in Clinical Pharmacokinetics, (5th Edition) 2010. American Society of Health Systems Pharmacist, Bethesda, MD.

5. Murphy JE. Aminoglycosides. In: Murphy JE, ed. Clinical Pharmacokinetics, 4th ed. Bethesda, MD: American Society of Health-System Pharmacists, 2008:27-60.

6. Winter ME. Basic clinical pharmacokinetics. 5th ed. Baltimore: Lippincott Williams and Wilkins; 2010.
7. Winter MA, Guhr KN, Berg GM. Impact of various body weights and serum creatinine concentrations on the bias and accuracy of the Cockcroft-Gault equation. Pharmacotherapy 2012; 32: 604-612 [PMID: 22576791 DOI: 10.1002/j.1875-9114.2012.01098.x]

Quotes: [Largest study so far....total of 3678 patients]
Regarding Salazar equation: This equation, however, was not consistently shown in studies to be a superior predictor of renal function. It is not widely used in clinical practice and has not been validated in pharmacokinetic studies. In addition, the Salazar-Corcoran equation is not recognized by the National Kidney Foundation.

Regarding CG -LBW equation: Our findings do not support those conclusions and are different from a recent investigation of Clcr in 54 morbidly obese patients that found that adjusting an obese patient's weight to a fat-free weight or lean body weight predicted a Clcr calculated with the C-G equation without bias. Notably, our study included 2065 obese or morbidly obese patients, far more than other published studies.

Conclusions: An unbiased C-G Clcr can be calculated using actual body weight in underweight patients and ideal body weight in patients of normal weight. Using ABW0.4 for overweight, obese, and morbidly obese patients appears to be the least biased and most accurate method for calculating their C-G Clcr. Rounding Scr in patients with low Scr did not improve accuracy or bias of the Clcr calculations.

## Trough Calculators

Allows the user to estimate the actual (extrapolated) trough based on the elimination rate constant and the number of hours the level was drawn before the next scheduled dose. A supratherapeutic level may be actually therapeutic if it was drawn just before the next dose. Trough drawn early? -Estimation Tool based on entered Kel
This new program can be used to determine when to administer the next dose of vancomycin after a supratherapeutic trough is obtained. An estimated elimination rate constant is generated from the creatinine clearance which is then used to determine the timing of the next dose based on the desired target trough concentration.
Vancomycin -Timing of next dose based on estimated Ke value

Use this program if the vancomcyin level is drawn early and you want to estimate the actual trough just before the next dose to determine if the current regimen is appropriate Vancomycin  Predicted Trough-Level drawn early

## Dosing by levels

Dosing by levels (Full) Dosing by levels  pharmacokinetics (quick) Non-Steady State kinetics

## Pharmacokinetics

Pharmacokinetics -Multiple Ke (Advanced version)Pharmacokinetic dosing -aminoglycosides/Vanco Original program

## Vancomycin  Single-level dosing

Vancomycin SINGLE Level-(dosing by levels) Original calc
If you would like to enter the time since the last dose was given, use this version. This new version may be especially useful if the trough was drawn late and thenext dose was delayed. Example: current regimen vanco 1 gram q12h. Trough wasdrawn 12.5 hours after the last dose.Vancomycin single-level  dose infused early or late

The GlobalRPh vancomycin single-level calculator uses the Vd recommended in Bauer's text: 0.7 L/kg. Use the advanced version if you wish to manipulate this value.Vancomycin single level Advanced version
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