SURFACE HEPARINIZATION OF CENTRAL VENOUS CATHETERS REDUCES MICROBIAL COLONIZATION IN-VITRO AND IN-VIVO - RESULTS FROM A PROSPECTIVE, RANDOMIZED TRIAL

Objective: To evaluate in vitro and in vivo the efficacy of covalent e nd point-attached heparin to single-lumen polyurethane central venous catheters in reducing microbial adherence and colonization. Design: In vitro study: A controlled bench study. In vivo study: A prospective, randomized, double-blind, clinical trial. Setting: Intensive care unit in a 1200-bed teaching hospital, Interventions: In vitro study: Adhes ion of 17 radiolabeled clinical isolates of Staphylococci to catheters was examined in vitro. In vivo study: The outcome of heparinized and control catheters was compared in vivo in patients receiving long term parenteral nutrition, Fifty-five adult patients were prospectively, b lindly randomized to heparinized or control central venous catheters, The catheters, removed on clinical grounds, were analyzed with semiqua ntitative and quantitative cultures. Blood cultures were done at cathe ter removal. Measurements and Main Results: In vitro study: Coagulase- negative Staphylococci adhered less in vitro to heparinizedcatheters t han to control catheters (p <.05). In vivo study: Among 32 central ven ous catheters, or patients who completed the study, catheter associate d bacteremia or fungemia was observed in five patients in the control group (n = 19) and in no patient with a heparinized catheter (n = 13) (p = .047), Four of 13 catheters in the heparin group were colonized c ompared with 14 of 19 in the control group (p = .03). Coagulase-negati ve Staphylococci were the most frequent microorganisms in both groups. The numbers of organisms found on colonized catheters were larger in the control group than in the heparin group. Conclusions: Covalent end point surface heparinization appears to have a great impact on both i n vitro and in vivo bacterial colonization of central venous catheters , Such heparinization can be a practical and economical approach to th e prevention of catheter-associated bacteremia or fungemia.