Colistin Pharmacokinetics in Critically Ill Patients During Extended Dialysis

Due to the lack of new antibiotics for the treatment of critically ill patients with multidrug-resistant bacteria, interest in "old" antibiotics like colistin re-emerged. Lastly, colistin is administered more frequently especially in cases of infections due to Pseudomonas aeruginosa, Klebsiella pneumoniae or Acinetobacter baumanii in intensive care units (ICUs) around the world. However, dosing of colistin in critically ill patients undergoing renal replacement therapy is based on scarce data. The aim of this study is to evaluate single and multiple-dose pharmacokinetics of both colistin and its inactive prodrug colistin-methanesulfonate (CMS) in critically ill patients with acute kidney injury (AKI) undergoing extended daily dialysis (EDD).

The investigators perform a prospective clinical pharmacokinetic single- and multiple-dose study in the medical and surgical ICUs of the Hannover Medical School. ICU patients with anuric AKI being treated with EDD and receiving i.v. colistin are studied on day 1 and (if possible) on day 5-9 of treatment. A loading dose of 6 Mio IU colistin ís administered 8 hours prior to the EDD session followed by 3 Mio IU every 8 hours. Colistin Plasma concentration levels as well as dialyzer clearance rates are measured at different time points.

Inclusion criteria

• Indication for colistin therapy
• Acute kidney injury AKIN III with need for renal replacement therapy

Exclusion criteria

• participation in other studies
• pregnancy
• known colistin allergy or other contraindications for colistin therapy