A comparison of contamination rates of intravenous admixtures when prepared on a hospital ward versus in a laminar flow hood

The contamination rates of some I.V. admixtures prepared in the pharmacy in a laminar flow hood by a pharmacist or a specially-trained technician were compared with some prepared by nursing on two wards. The microbial contamination due to the drug additive procedure was measured using the membrane filtration method. The risk of introducing microbial contamination was found to be very high (29 per cent) in the solutions mixed on the wards. On the other hand, no contamination was found in solutions of identical formulas when mixed by pharmacists or trained technicians in a laminar flow hood. The microorganisms which were isolated from the contaminated samples seem to have been introduced into the I.V. admixtures due to poor hand washing practices, poor aseptic tecnhique, and inadequate environmental controls. These studies strongly indicate that I.V. admixtures should be prepared in a laminar flow hood by a pharmacist or a trained technician in order to minimize the chances of contamination.