Surface heparinization of central venous catheters reduces microbial colonization in vitro and in vivo: Results from a prospective, randomized trial

OBJECTIVETo evaluate in vitro and in vivo the efficacy of covalent end point-attached heparin to single-lumen polyurethane central venous catheters in reducing microbial adherence and colonization. DESIGNIn vitro studyA controlled bench study. In vivo studyA prospective, randomized, double-blind, clinical trial. SETTINGIntensive care unit in a 1200-bed teaching hospital. INTERVENTIONSIn vitro studyAdhesion of 17 radiolabeled clinical isolates of Staphylococci to catheters was examined in vitro. In vivo studyThe outcome of heparinized and control catheters was compared in vivo in patients receiving long-term parenteral nutrition. Fifty-five adult patients were prospectively, blindly randomized to heparinized or control central venous catheters. The catheters, removed on clinical grounds, were analyzed with semiquantitative and quantitative cultures. Blood cultures were done at catheter removal. MEASUREMENTS AND MAIN RESULTSIn vitro studyCoagulase-negative Staphylococci adhered less in vitro to heparinized catheters than to control catheters (p < .05). In vivo studyAmong 32 central venous catheters, or patients who completed the study, catheter-associated 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 compared with 14 of 19 in the control group (p = .03). Coagulase-negative 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. CONCLUSIONSCovalent end point surface heparinization appears to have a great impact on both in vitro and in vivo bacterial colonization of central venous catheters. Such heparinization can be a practical and economical approach to the prevention of catheter-associated bacteremia or fungemia.(Crit Care Med 1996; 24:1482-1489)