The ONTAI study - a survey on antimicrobial dosing and the practice of therapeutic drug monitoring in German intensive care units.

Purpose: Optimization of antibiotic therapy is still urgently needed in critically ill patients. The aim of the ONTAI survey (online survey on the use of Therapeutic Drug Monitoring of antibiotics in intensive care units) was to evaluate which strategies intensive care physicians in Germany use to improve the quality of antibiotic therapy and what role a Therapeutic Drug Monitoring (TDM) plays.

Methods: Among the members of the German Society for Anaesthesiology and the German Society for Medical Intensive Care Medicine and Emergency Medicine, a national cross-sectional survey was conducted using an online questionnaire.

Results: The questionnaire was completely answered by 398 respondents. Without TDM, prolonged infusion was judged to be the most appropriate dosing regimen for beta lactams. A TDM for piperacillin, meropenem and vancomycin was performed in 17, 22 and 75% of respondents, respectively. For all beta lactams, a TDM was requested more often than it was available. There was great uncertainty as to the optimal pharmacokinetic/pharmacodynamic index for beta-lactams. 86% of the respondents who received minimal inhibitory concentrations adapted the therapy accordingly.

Conclusion: German intensive care physicians are convinced of TDM for dose optimization. However, practical implementation, the determination of MICs and defined target values are still lacking.