You are here
Home > Medical Calculator > Vancomycin SINGLE Level – original calc

Vancomycin SINGLE Level – original calc

Vancomycin - Single Level Analysis
Patient:   Location:
Drug:   Weight:   
Current dose being given:   mg  
Current dosing interval: hrs
--------------------------------------------------------

Current infusion time (hrs):

Single level drawn - Trough
Trough level obtained:    mcg/ml
When was the trough drawn?:
Enter number of hours before next dose:    hrs
[Hint:     0.01 = <1 minute before next dose.     0.08 = ~5 minutes before next dose]

  If you would like to enter the time since the last dose was given, use this version.new
This new version may be especially useful if the trough was drawn late and the
next dose was delayed. Example: current regimen vanco 1 gram q12h.   Trough was drawn 12.5 hours after the last dose.
Desired peak:   mcg/ml    Desired trough:      mcg/ml

Updates
A new program was created 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.

I also updated our current trough calculator to also generate an estimated vancomycin kel value based on the creatinine clearance.   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 - link to new program.)

Background
Ambrose-Winter's Single Trough Method
Principles:
A population Vd is used to estimate the [Peak].
This calculated [Peak] and measured [Trough] are then used to calculate an elimination rate constant (kel).

[Peak]=measured [Trough] + Dose/Vd
kel = ln ([Peak]/[Trough])/Tau
Infusion equations are then used to calculate a new Tau and Dose.

Side note: the GlobalRPh calculator uses the Vd recommended in Bauer's text: 0.7 L/kg.
       Use the advanced version if you wish to manipulate this value.

Reference

Ambrose PJ, Winter ME. In: Winter ME. Basic clinical pharmacokinetics, 4th ed. Philadelphia: Lippincott Williams & Wilkins; 2004:451-76.


Alternate expression of kel equation:
single level

Normally kel = (Ln C1 / C2) / (t2 - t1)
C1= actual or extrapolated Peak; or post peak level
C2= actual or extrapolated trough; or random level
Drawn at least 1.5 x estimated half-life after first level.
(t2 - t1) = Time difference between levels.

Equation 15.5 page 455:
cmax =   [cmin + dose (s) (f)] / Vd

Related pharmacokinetic calculators




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 led
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

Vancomycin - Empiric dosing


Vancomycin Empiric dosing - AUC/MIC
Vancomycin SINGLE Level – original calc

thpxl