TOUCH CONTAMINATION OF CONNECTION DEVICES IN PERITONEAL-DIALYSIS - A QUANTITATIVE MICROBIOLOGIC ANALYSIS

Objective: To determine the level of bacterial contamination associate d with touch contact of a connector set during peritoneal dialysis (PD ). Design: The experiment utilized a laboratory-based simulation of a bag exchange procedure. Deliberate touch contamination of the connecto r set spike was followed by quantitative recovery of micro-organisms f rom the connector and, in some cases, the dialysis bag. Subjects: Pati ents undergoing PD were used as the ''test'' group. Departmental secre tarial and laboratory staff served as the comparative control group. S etting: The patients were voluntary subjects from a PD outpatients uni t and were tested in their own homes. Outcome: The numbers of micro-or ganisms contaminating a connector set and entering the dialysis bag du ring a touch-contamination event were determined. Additionally we iden tified hand hygiene and, in particular, the care taken to dry the hand s after washing as being highly relevant to microbial touch-contaminat ion levels. Patient hand disinfection, as practised in most PD units, effectively reduced touch contamination to low levels. Results: Touch contamination of a connector set with unprepared hands led to fewer th an 100 micro-organisms translocating from fingers to the spike. If the hands were washed but not dried before touch contact was made, up to 4500 micro-organisms translocated to the connector set spike. Air-towe l drying of washed hands before touch contact reduced the translocatin g numbers by 95% - 99%. Hand disinfection, as routinely practiced by P D patients, reduced the bacterial numbers reaching the peritoneal cavi ty after touch contamination to <5. The range of micro-organisms isola ted from the fingers of PD patients using hand disinfectants on a regu lar basis showed considerably more diversity than the control group. C onclusion: Hand care prior to bag exchange has a major effect on touch -contamination levels. Accidental touch contact of connecting devices by unprepared hands using a PD-bag exchange procedure leads to the tra nslocation of 500 micro-organisms or fewer to the connector device. If the hands are wet at the time of contact the number translocating can be as high as 4500. Hand drying with and air towel before touch conta ct reduces the numbers translocating by 95% - 99%. Hand disinfection p rocedures carried out prior to bag exchange minimizes touch-contaminat ion levels.