Recent evidence has suggested that a moist environment plays an important role in wound healing. Karayahesive, one type of hydrocolloidal dressing, contains natural karaya gum as a hydrophilic gel. We applied hydrocolloidal dressing to operative wounds in 147 patients who underwent cardiovascular surgery from April 2001 through August 2002 to evaluate its clinical usefulness. The dressing was kept on the wounds for 7 days after operation, but was immediately switched to conventional dressing with gauze if there was any problem. A total of 144 patients (98%) had no wound chest infections. Good wound healing was obtained with only 1 dressing, removed 7 days after operation, in 128 patients (87%). In 19 patients (13%), the hydrocolloidal dressing was switched to conventional dressing. In 13 of these patients the hydrocolloidal dressing dissolved naturally or exudation occurred; clinically, there were no local problems; however, 3 patients had infection, 2 had fat necrosis, and 1 had burn injury caused by electrocautery. No patients had skin problems caused by this dressing. We conclude that hydrocolloidal dressing can be used safely and effectively in patients undergoing cardiovascular surgery and reduce the workload of healthcare workers.