Background: This study aims to assess clinicians' behaviour in prescribing vancomycin in the Intensive Care Unit (ICU) and their adherence to local guidelines for therapeutic drug monitoring (TDM).
Methods: In this observational cohort study we included all consecutive patients admitted to a 28-bed multidisciplinary mixed adult ICU of a large university hospital in Amsterdam between January 2002 and September 2007 who were prescribed vancomycin for ≥ 3 days. We measured guideline adherence by checking for each given advice the corresponding action and monitored adherence over time using Statistical Process Control.
Results: In 475 patients prescribed vancomycin, 1336 serum concentrations were measured, of which 598 in time and 738 with a median delay of 31 hours. Dose or dose frequency adjustments were often not done (54% in advice 2 [half dose frequency] and 86% in advice 4 [increase dose with 50%]) or not done concordantly (32% in advice 2 [half dose frequency] and 60% in advice 7 [half dose frequency if trough serum concentration]). Although adherence was stable over time, the average level was low (58.7%).
Conclusion: Five years of TDM did not achieve the desired prescription behaviour in the ICU and clinicians feel there is a need for computerized decision support. Local projects should measure adherence and implement appropriate solutions.