Vancomycin Dosing Calculator (beta)
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Co-developed by Matthew Girgis - ID PharmD trained in Boston, currently
fighting drug resistant bugs in Toronto, Canada. |
Select method of dosing
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AUC Target:
0-24 |
Multi-calc: Empirically
derived or based on levels
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Patient:
Location:
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Age:
Sex: Serum Creatinine:
Height:
Weight:
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Levels (if available) - Select
option above first
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Peak level
(first) obtained: mcg/mL
Number hours post dose:
hrs
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Trough level (2nd) obtained: mcg/mL
Number hours post dose:
hrs
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Current dose being given: mg
Current dosing interval:
hrs
Quick Version (only):
First level
(peak):
2nd level:
Time difference
(hours):
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Empiric only
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Ignore if levels available.
Background information
Elimination rate
constant:
Volume of Distribution:
Select Vd: L/kg
- Normal = 0.65
- Obese =
0.5
- Dehydrated = 0.6
- Overhydrated = 0.7-0.85
- Septic
Shock/ICU/Trauma = 0.7-0.75
- Pregnant in 3rd Trimester or <48h post
partum = 0.7
Modifications to the Vd based on body weight:
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Amputations (Optional Field)
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(optional)
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Addition data required for further analysis.
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Desired Peak:
mcg/ml Desired Trough:
mcg/ml
Infusion time (ti):
Info
[AUC guided recommendations will appear on the results
page]
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Process form entries
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References
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This latest version is based on a comprehensive review of the most recent pharmacokinetic textbooks. Some of the sources used are listed here
- Bauer LA. The Aminoglycoside Antibiotics. In Bauer LA, ed. Applied
Clinical Pharmacokinetics. 2nd ed. New York, NY: McGraw Hill Medical;
2008:97-206.
- Bauer LA. Vancomycin. In Bauer LA, ed. Applied Clinical
Pharmacokinetics. 2nd ed. New York, NY: McGraw Hill Medical; 2008:207-298.
- Burton ME, Shaw LM, Schentag JJ, Evans WE. Applied Pharmacokinetics &
Pharmacodynamics: Principles of Therapeutic Drug Monitoring. 4th ed.
Philadelphia: Lippincott Williams & Wilkins; 2006.
- 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.
- Murphy JE. Aminoglycosides. In: Murphy JE, ed. Clinical Pharmacokinetics, 4th
ed. Bethesda, MD: American Society of Health-System Pharmacists, 2008:27-60.
- Winter ME. Basic clinical pharmacokinetics. 5th ed. Baltimore: Lippincott
Williams and Wilkins; 2010.
- Rybak MJ, Le J, Lodise TP,Levine DP, Bradley JS, Liu C, et al.
Therapeutic monitoring of vancomycin: A revised consensus guideline
and review of 1the American Society of Health-System Pharmacists,
the Infectious Diseases Society of America, the Pediatric Infectious
Diseases Society and the Society of Infectious Diseases Pharmacists.
Accessed: May 2019. [Link]
- 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. |
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