Vancomycin Protocol Flashcards
What does vancomycin covers?
Serious infections due to -lactam-resistant Gram positive organisms (i.e. methicillinresistant S. aureus or S. epidermidis, or ampicillin-resistant enterococci)
.
Staph, Strep, and Entercocci
What is the absorption characteristic of oral doses of vancomycin?
Oral doses are poorly absorbed and not recommended for systemic infections
Oral administration is primarily ineffective for systemic infections.
What is the volume of distribution (Vd) range for vancomycin?
0.4-1 L/kg
Vd reflects how extensively the drug distributes throughout the body.
What is the protein binding percentage for vancomycin?
10-50%
Protein binding can affect the drug’s efficacy and clearance.
Does vancomycin have active or inactive metabolites?
No active or inactive metabolites
This indicates that vancomycin is not metabolized into other forms in the body.
What is the primary route of elimination for vancomycin?
Primarily renal elimination (>80-90%)
Renal function significantly impacts the dosing and clearance of vancomycin.
What is the elimination half-life of vancomycin with normal renal function?
6-12 hours
This half-life can vary based on individual renal function.
What is the optimal efficacy target AUC/MIC ratio for serious MRSA infections?
400-600 mg·h/L
This range is associated with good clinical outcomes.
What vancomycin trough levels should approximate an AUC/MIC of 400 mg·h/L?
15-20 µg/mL
These trough levels are recommended for optimal efficacy.
Toxicity of Vanco
Nephrotoxicity is reported ≤ 5% of cases…what are risk factors
Doses > 4g/day
Actual body weight ≥ 101.4 kg
Troughs > 15 mcg/mL or continuous infusion levels > 28 mcg/mL for prolonged
durations
Pre-existing renal dysfunction
Concomitant use of nephrotoxins (e.g. diuretics, contrast dye, and
aminoglycosides)
Red man syndrome…not true toxicity..talk about it
B. Red man syndrome is characterized by hypotension and/or erythematous rash on face and upper body
i. Often mistaken for an allergy but should not be considered a true allergy
ii. Can be alleviated by decreasing infusion rate to < 10 mg/minute or less
Vancomycin Intermittent Infusions (IIs)…indication and loading dose
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Indication for Loading Dose:
- Consider for patients with severe infections, critically ill, or on hemodialysis due to the long half-life.
-
Loading Dose:
- 20-25 mg/kg (max 2.5 g).
- Based on total body weight, regardless of renal function.
Vanco Dosing nomogram
Vancomycin Maintenance Dose and schedule
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Maintenance Dose:
- 15-20 mg/kg/dose based on total body weight, unless weight is > 130% of ideal body weight (IBW), then use adjusted body weight (ABW).
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Dosing Schedule:
- Start maintenance dose at next scheduled interval (e.g., LD at 12:00, first maintenance at 20:00 for q8h dosing).
-
Consider q12h Dosing for:
- Renal transplant patients (SCr may not reflect CrCl).
- Elderly patients > 65 yrs (SCr may not reflect CrCl).
- Uncomplicated infections (e.g., skin/soft tissue infections in stable patients).
-
Infusion Guidelines:
- Administer in dilute solution (≤ 5 mg/mL) and infuse at 10-15 mg/min to minimize infusion-related reactions.
Vancomycin Continuous Infusions (CIs): indication, timing, LD/MD
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Indications:
- For serious MRSA infections (e.g., sepsis, bacteremia, pneumonia, CNS infections, osteomyelitis) or prolonged vancomycin therapy to optimize AUC/MIC.
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IV Access:
- Requires dedicated IV access with no interruptions.
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Timing:
- CI may start immediately after the loading dose (or last dose) once appropriate IV access is obtained.
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Loading Dose:
- 15-20 mg/kg (max 2.5 g), based on total body weight, regardless of renal function.
-
Maintenance Dose:
- 30-40 mg/kg (up to 60 mg/kg), to achieve steady-state concentrations of 20-25 mg/L.
Q: How should vancomycin serum levels be drawn?
A: Vancomycin serum levels should be drawn from a peripheral stick, preferably from the arm opposite the infusion site.
Q: When should vancomycin levels be drawn for intermittent infusions at steady state?
A:
Trough only: Draw the trough level before the 4th dose, assuming the dose is given at its regular dosing interval.
AUC calculations:
Draw the 1st level 1 hour after the end of the infusion.
Draw the 2nd level 30 minutes prior to the next dose.
Q: When should vancomycin levels be drawn for continuous infusions?
A: Obtain a random level 24 hours after initiation of CI or after 12 hours if the patient was transitioned from an intermittent infusion.
Q: How should vancomycin levels be drawn in patients on hemodialysis?
A:
Draw the level pre-dialysis (pre-HD level).
Alternatively, draw post-dialysis (≥ 2 hours after dialysis).
Q: When should a vancomycin level be drawn sooner in patients with suspected acute kidney injury (AKI)?
A: Consider drawing a level if:
SCr change ≥ 0.3 mg/dL within 48 hours.
SCr increase ≥ 1.5 times baseline within the past 7 days.
Urine output < 0.5 mL/kg/h for 6 hours (oliguria)
Vancomycin level
Vancomycin Monitoring for Patients on Hemodialysis
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Vancomycin Removal:
~30-50% of vancomycin is removed during a 4-hour hemodialysis session. -
Pre-HD Vancomycin Levels and Dosing:
- Pre-HD level < 10 mcg/mL: Give 1000 mg after HD.
- Pre-HD level 10-20 mcg/mL: Give 500 mg – 1000 mg after HD.
- Pre-HD level > 20 mcg/mL: Hold vancomycin, re-dose when the level is within the goal range.
Vancomycin Monitoring for Supra-Therapeutic Levels or AKI
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Action for Supra-Therapeutic Levels or AKI:
- Hold vancomycin to allow sufficient time for clearance before restarting the next dose.
- Check a random vancomycin level and re-dose when the level falls below the goal range.
- Reduce the total daily dose to avoid vancomycin re-accumulation.
