PHARMACOKINETICS AND CLEARANCE OF CIPROFLOXACIN AND AMIKACIN DURING CONTINUOUS HEMODIALYSIS

We studied the pharmacokinetic and clearance of a 200 mg ciprofloxacin and a 500 mg amikacin intravenous dose during 5 continuous hemodialyses procedures in 5 patients with acute oliguric renal failure. Hourly blood and ultrafiltrate drug concentrations were measured during 8 hours. Dialysate flux (Qd) was 16.6 ml/min during the first hours and 33.2 ml/mn thereafter. For each Qd, total ciprofloxacin clearance was 1.13+/-0.99 and 2.8+/-1.71 ml/min (p<0.0001), diffusive clearance was 0.96+/-0.87 and 2.47+/-1.56 ml/min (p<0.005) and convective clearance was 0.16+/-0.17 and 0.33+/-0.2 ml/min (p<0.05). Likewise, total amikacin clearance was 3.47+/-1.31 and 4.18+/-0.53 ml/min (p<0.001), diffusive clearance was 2.97+/-1.24 and 3.86+/-0.52 ml/min and convective clearance was 0.50+/-0.47 and 0.32+/-0.29 ml/min (p=NS). Protein binding was 84% for ciprofloxacin and 77% for amikacin. It is concluded that during continuous hemodialysis with cuprofan membrane, the main transport mechanism of ciprofloxacin and amikacin is diffusive. Very low amounts of ciprofloxacin are depurated by the dialyser. Likewise, the shortening of amikacin half life suggests the presence of other elimination pahway and the need to use supplementary doses every 24 hours.