A prospective, randomized, controlled trial comparing transparent polyurethane and hydrocolloid dressings for central venous catheters

Background: This study was undertaken to determine the frequency of skin co lonization, hub colonization, and central venous catheter colonization in t ransparent hydrocolloid versus standard polyurethane dressings. Methods: Adult patients requiring the insertion of a multilumen central ven ous catheter in an intensive care unit were randomized to receive either a standard polyurethane dressing or a transparent hydrocolloid dressing. Cult ures were obtained from 125 skin insertion sites, 141 catheter hubs, 128 ca theter tips, and blood samples from 132 patients. Extensive data on patient and catheter characteristics were collected, Results: Skin and hub cultures revealed no significant difference in degree of colonization. However, the hydrocolloid group had a significantly highe r level of catheter colonization than the polyurethane group (P = .048). Co nversely, there was a significantly higher frequency of positive blood cult ures in the polyurethane group (P = .03), although the majority were consid ered to be potential contaminants. There were only 6 cases in which the sam e species was simultaneously isolated from a positive blood culture and a c olonized catheter, 5 from the hydrocolloid group and 1 from the polyurethan e group. Conclusions: The results of this study suggest that an increased risk of ca theter colonization is associated with the use of hydrocolloid dressings, d espite previous research suggesting that they significantly reduce microbia l growth compared with standard polyurethane, The clinical significance of increased numbers of positive blood cultures in the polyurethane group requ ires further examination, although distinguishing between contamination and true infection in intensive care settings continues to be methodologically challenging. Further studies are required to determine whether these findi ngs are generalizable across different study settings and whether similar o utcomes are obtained when different brands of hydrocolloid dressing are use d.