The Y Set with Disinfectant is Here to Stay

T en years ago, Oreopoulos introduced his original connection system, the flexible and wearable rolled bag, and made continuous ambulatory peritoneal dialysis (CAPD) clinically feasible. It remains the standard technique. In 1979, he wrote a paper entitled "Peritoneal dialysis is here to stay ," predicting a great future for the new technique (1) which was used in several thousands of patients allover the world. However, the diffusion of the technique, which should have been extensive considering its many clinicalmetabolic-logistic-economic advantages, was restricted after a positive start. This unfortunate outcome reflects two main problems inherent in the connection system: the unacceptably high incidence of infectious peritonitis, and the negative asthetic of the cumbersome bag. The frequency of peritonitis, due mainly to exoge nous grampositive bacteria, remained high despite all efforts to reduce it, for example, accurate selection of the patients, sophisticated training systems, etc. Also disappointing were the new systems introduced during the last two years, either original or variants of the standard system. None of these proved to be significantly better than the standard in preventing peritonitis; almost all of them added further problems and complications, except for the y set with disinfectant. This connection, also called Perugia system, has proved its ability to significantly reduce the peritonitis rate. This system was introduced into clinical practice in 1979 (2, 3) and the first clinical results were published in 1980 (4) and 1983 (5). Since then, the efficacy of the system has been largely confirmed by a great number of uncontrolled but substantial trials (6-13) and also by some meticulous prospective controlled trials (14). During the last few years, experience has grown steadily and rapidly chiefly in Italy where more than 95% of CAPD patients are on this system. Unfortunately, for several reasons the spread of the original system outside Italy has been disappointingly slow, while some variants without the disinfectant, including Baxter's 0 set@, have been more widely used despite less evidence of efficacy. However, the impasse, which confined connector technology for many years, finally forced many groups outside Italy to test the y set with disinfectant. Many studies are underway. The results of the first prospective controlled randomized trial involving a large number of patients from many diff'erent nonItalian centers (published elsewhere in this issue ) confirm the high efficiency of the system (15). In this same issue (16), another article confirms the importance of flush before fill (made possible by the y connector) in reducing the degree of bacterial contamination; however, the initial in vitro study (4) and subsequently others (1718) have confirmed its inability to guarantee complete removal of bacteria. These studies indicate the absolute need for a disinfectant to sterilize the connection. Another important feature of the Perugia system is that, while it prevents peritonitis, it also permits the spent bag to be disconnected between exchanges, thus providing acceptable aesthetics. This eff'ect is best achieved with the miniaturized version of the Y which gives some improvement in effectiveness and safety (7), probably because the small area of the prosthesis reduces the surface where the bacteria can adhere; it also reduces the volume of the disinfectant needed and the side effects of its accidental contact with the peritoneum. The third study on this subject in this issue (19) confirms this effectiveness. In conclusion, there is no longer any doubt regarding the superiority of the Y set with disinfectant in terms of effectiveness in preventing peritonitis and it esthetical acceptance. Moreover, this device is simple, handy and cheap and should be considered the golden standard in the treatment of chronic renal failure patients with CAPD. Its general adoption now is mandatory if we want to promote the wider use of CAPD and thus reduce the incidence of peritonitis to an acceptable level. Thus, we believe we are authorized to update Oreopoulos' title and say "The Y set is here to stay".