Elimination of piperacillin and tazobactam by renal replacement therapies with AN69 and polysulfone hemofilters: evaluation of the sieving coefficient.
OBJECTIVE
Piperacillin-tazobactam is commonly used to treat infections in ICU patients. Controversial data have been published about the sieving/saturation coefficient (Sc/Sa) of piperacillin during continuous renal replacement therapies (CRRT). The objective was to evaluate the Sc/Sa of piperacillin-tazobactam during continuous venovenous hemofiltration (CVVH) and continuous venovenous hemodialysis (CVVHD) using AN69 and polysulfone.


METHODS
Ringer lactate, BSA-containing Ringer lactate and plasma were circulated at 150 ml/min. The ultrafiltrate/dialysis flow was kept at 1,500 ml/min. A bolus was injected and samples were taken. Drugs were measured using HPLC. Sc/Sa was calculated according to standard formula.


RESULTS
Free passage of drugs through the membranes was reported with protein free solutions. In the presence of proteins the Sc/Sa lowered and correlated to protein free fraction. Polysulfone had a significantly higher permeability than AN69 during CVVH.


CONCLUSIONS
Drug binding to albumin contributes to the decrease of the Sc/Sa of piperacillin but it does not completely justify the in vivo value obtained by some authors.
Arzuaga
A
A
Laboratory of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of the Basque Country, Vitoria-Gasteiz, Spain.
Isla
A
A
Gascón
A R
AR
Maynar
J
J
Corral
E
E
Pedraz
J L
JL
D000180:Acrylic Resins / Q000009:adverse effects*; D000181:Acrylonitrile / Q000009:adverse effects / Q000031:analogs & derivatives*; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001672:Biocompatible Materials / Q000009:adverse effects; D003422:Critical Care; D004359:Drug Therapy, Combination; D006440:Hemofiltration / Q000009:adverse effects / Q000295:instrumentation; D006801:Humans; D066298:In Vitro Techniques; D008567:Membranes, Artificial; D010397:Penicillanic Acid / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D010878:Piperacillin / Q000493:pharmacokinetics*; D011108:Polymers / Q000009:adverse effects; D018709:Statistics, Nonparametric; D013450:Sulfones / Q000009:adverse effects; D000078142:Tazobactam
D000180:Acrylic Resins; D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D008567:Membranes, Artificial; D011108:Polymers; D013450:Sulfones; C017662:polysulfone P 1700; C016892:AN-69; D010397:Penicillanic Acid; D000181:Acrylonitrile; D000078142:Tazobactam; D010878:Piperacillin