Article Text

Download PDFPDF
PKP-017 Impact of a bayesian pharmacokinetic dosing programme of vancomycin on clinical outcomes
  1. M Moreno Santamaria,
  2. A Gomez Sanchez,
  3. V Faus Felipe,
  4. B Tortajada Goitia
  1. Costa Del Sol Hospital, Pharmacy, Marbella, Spain


Background The recommended starting dose of vancomycin is 25–30 mg/kg followed by 15–20 mg/kg/12–8 h (adjusted if there is renal impairment). Early plasma concentrations (PC), after 3 doses, should be obtained as soon as possible to determine if therapeutic levels (TL) have been reached (10–20 µg/ml).

Purpose To describe patients and indications, and to analyse treatments and a pharmacokinetic monitoring plan. To assess efficacy and its relation with PC and AUC/MIC, and nephrotoxicity (0.5 mg/dL or 50% creatinine increase).

Material and methods Retrospective study of vancomycin treatment guided by pharmacokinetic monitoring (Bayesian method) over 5 months. ICU, haemodyalisis, paediatrics, duration <5 days and de-escalations were excluded. Descriptive analysis through median and interquartile range (IR); frequency distribution for categories; quantitative variables comparison with clinical cure using the Mann-Whitney test (p < 0.05 for significance).

Results 87.9% of treatments were monitored (n = 22). Patients were 64 years (IR=22), CrCl=96 mL/min (IR=71.5) and 77.3% showed some nephrotoxicity risk factor.

22.7% were skin/soft tissue (40% E faecium, 20% MRSA, 20% CNS), intra-abdominal 18.2% (66.7% E faecium, 33.3% CNS), bacteraemia 13.6% (100% CNS), catheter 13.6% (100% CNS), pneumonia 9.1% (100% MRSA), urinary tract 9.1% (100% Enterococcus), 9.1% without a clear focus and 4.5% non-pneumonia respiratory infections (100% MRSA). 100% E faecium showed MIC ≤4, 100% MRSA MIC ≥1.5, 50% CNS MIC ≥2.

No loading dose was administered. Initial dosage was appropriate in 31.8%; 68.2% was under dosed.

The first PC was obtained after 3 days (IR=2.25); 50% were delayed beyond the third dose and 42% were subtherapeutic. TL were obtained after 5 days (IR=4). Pharmacokinetically guided dosing showed 72.7% of patients achieved TL (18.2% above; 9% under range).

Clinical cure rate was 77.3%. By indication: 100% bacteraemia, urinary and non-pneumonia respiratory infections were cured; 80% skin/soft tissues; 75% intra-abdominal; 66.6% catheter; 50% pneumonia; and 50% without focus. By microorganism: 87.5% CNS; 66.7% E faecium; and 66.7% MRSA. There was no statistically significant difference in clinical cure related to PC or AUC/MIC although there was a tendency to higher PC in the cure group (16.7 µg/mL vs 12.13 µg/mL). 9.1% of patients developed nephrotoxicity.

Conclusion Although most treatments were pharmacokinetically monitored, the first level was delayed in half of the patients; 68.2% of treatments were initially under dosed. This led to delay in achieving TL. A relationship was not found between clinical cure and PC or AUC/MIC, probably due to the small sample size.

No conflict of interest.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.