Pharmacokinetics of ciprofloxacin in ICU patients on continuous veno-venous haemodiafiltration

Objectives: To investigate the pharmacokinetics of intravenous ciprofloxaci n 200 mg every 8 h in critically ill patients on continuous veno-venous hae modiafiltration (CVVHDF), one form of continuous renal replacement therapy (CRRT). Design and setting: Open, prospective clinical study in a multidisciplinary , intensive care unit in a university-affiliated tertiary referral hospital . Patients: Sis critically ill patients with acute renal failure on CVVHDF. Interventions: Timed blood and ultrafiltrate samples were collected to allo w pharmacokinetics and clearances to be calculated of initial and subsequen t doses of 200 mg intravenous ciprofloxacin. CVVHD was performed with 1 l/h of dialysate and 2 l/h of predilution filtration solution, producing 3 lih of dialysis effluent. The blood was pumped at 200 ml/min using a Gambro BM M-10 blood pump through a Hospal AN69HF haemofilter,. Measurements and results: Ten pharmacokinetic profiles were measured. The C VVHDF displayed a urea clearance of 42 +/- 3 ml/min, and removed ciprofloxa cin with a clearance of 37 +/- 7 ml/min. This rate was 2-2.5 greater than p reviously published for ciprofloxacin in other forms of CRRT. On average th e CVVHDF was responsible for clearing a fifth of all ciprofloxacin eliminat ed (21 +/- 10%). The total body clearance of ciprofloxacin was 12.2 +/- 4.3 l/h. The trough concentration following the initial dose was 0.7 +/- 0.3 m g/l. The area under the plasma concentration time curves over a 24-h period ranged from 21 to 55 mg .h l(-1). Conclusions: Intravenous ciprofloxacin 600 mg/day in critically ill patient s using this form of CRRT produced adequate plasma levels for many resistan t microbes found in intensive care units.