Water permeation through polyvinyl chloride bags without overwrap

Water loss by permeation from polyvinyl chloride i.v. containers (Viaflex, Travenol Laboratories) without an overwrap is reported. Viaflex bags without the overwrap containing 0.9% sodium chloride injection or 5% dextrose injection in 50-ml, 100-ml, 500-ml, and 1000-ml sizes were used. All sizes were stored at room temperatures (25 degrees C) and in a refrigerator (4-8 degrees C); the two smaller sizes were additionally in a frost-free freezer (-20 degrees C) and in a non-frost-free freezer (-20 degrees C). Ten bags of each type were stored for 84 days; each container weighed on days 0, 7, 14, 21, 28, 42, 56, 70, and 84 days. Based on the weight change exhibited during this initial period, the time required to lose 10% of the weight was predicted. The bags were stored for that period of time and then weighed. The weight loss exhibited zero-order kinetics. At room temperature, the 50-ml containers of both solutions lost greater than 10% during the 84-day period. During this time, the 100-ml containers of both solutions lost 9% of their weight. Weight loss in the larger sizes was less than 5% during the 84-day period at room temperature. Under the colder storage conditions, weight loss averaged much less than 5% for all sizes during the 84 days. During extended storage, weight loss continued at the same rate for the 100-ml container but was slower for the larger sizes. The Viaflex container without the overwrap may be stored in a refrigerator or freezer for up to 84 days without substantial loss of water by permeation.