Intrinsic and extrinsic microbial contamination of home total parenteral nutrition manufactured in eva-infusion bags (the i.v. bag).

Microbial contamination of total parenteral nutrition including fat emulsions in 1-3 litres plastic infusion bags (the i.v. bag) was studied during production in the pharmacy and administration both at home and in the hospital. Production contamination was investigated by dispensing test bags containing growth medium mixed with dextrose-salt solution. In this highly sensitive system, contamination was detected in less than 4% of cases. In-use contamination was estimated at the end of the infusion. The average contamination rate (+/- growth) in the five patients studied was 6.7% accompanied by considerable variation. Identification of the contaminants revealed that 85% of the contaminated bags contained staphylococci, indicating skin contamination. An investigation on the effect of the procedure used for attaching the infusion set on the contamination rate, was carried out with bags that contained sterile growth medium. This showed no contamination in 14 cases indicating the catheter as the most plausible source of contamination. It is concluded that both production in the community pharmacy and administration in the home are not associated with a higher microbial contamination than in central hospitals. It is, however, recommended that the microbial quality of the production process and the administration procedure are regularly monitored.