Exit-site healing post catheter implantation.

The study goals were (1) to describe the natural healing process post peritoneal dialysis catheter implantation; (2) to discern factors that predispose to exit infection; (3) to recognize signs of early exit-site infection; and (4) to ascertain the influence, if any, of the healing process on subsequent peritonitis rates and final catheter outcomes. There were 226 evaluations of 43 exits [range 3-6 per exit, mean 5.2 + or - 1.1 (SD)] in 41 patients. Eleven exits were in the parasternal area and 32 exits were in the abdomen. Exit sites and sinus tracts were examined weekly for 6 weeks with a magnifying loupe and macro-photographed. Cultures were taken from sterile saline sinus washouts, periexit smears, and nares. Exit sites were categorized into four types: (1) fast-healing exits had no drainage or minimal moisture deep inside by the third week; epidermis started to enter into the sinus within 2-3 weeks, progressed steadily, and covered at least half the visible sinus tract 4-6 weeks after implantation; (2) in slow-healing exits without infection, epidermis started to enter into the sinus after 3 weeks or progressed slowly and did not cover half the visible sinus by 5 weeks; the sinus might have had serous or serosanguineous, but never purulent, drainage persistent up to 4 weeks; (3) healing interrupted by infection initially looked identical to the fast-healing exit, but within 6 weeks the epidermis did not progress or regress, granulation tissue became soft or frankly fleshy; drainage increased and/or became purulent; (4) in slow-healing exits due to early infection, granulation tissue became soft or fleshy and/or drainage became puru lent by 2-3 weeks; sinus epidermization was delayed or progressed slowly, only after infection was appropriately treated. Compared with patients with fast-healing exits, patients with early infected exits were more likely (although not significantly) to be diabetics, to have an abdominal catheter, wound hematoma, higher body mass index, and higher percentage of positive cultures for Staphylococcus aureus in nares. Early colonization of the exit was the most significant factor in determining the healing pattern: the later the colonization, the better the healing. Positive culture from either washout or periexit smear one week after implantation was associated with early exit infection, a higher peritonitis rate, and a high probability of catheter loss due to an exit/tunnel infection, and higher peritonitis rate; however, the time to the first peritonitis episode was not shorter than in the groups with later exit colonization. We postulate that exit infections and peritonitis rates may be decreased by delaying exit colonization using prophylactic antibiotics for at least 2 weeks after implantation and sterile exit dressing procedure for the entire healing time of approximately 6 weeks.