Consequences of inadvertent microbial contamination of dextrose solutions

Most intravenous infusion fluids and non-sterile liquid products contain dextrose which serves as a sweetener or an energy source for critically ill or traumatized patients. Hence dextrose was critically examined for stability in the presence of some micro-organism which are commonly known to contaminated i.v. infusion fluids. In the presence of these test organisms, the dextrose component of these solutions was found to be remarkably degraded with average rates of 0.065-3.153% per hour depending on the type of organism. Micro-organisms such as Ps. aeruginosa and E. coli gave low rates of degradation of 0.065-0.88% per hour while the values of 0.770-3.153% per hour were obtained for K. pneumonia; B-lac+ Staph. aureus and B. subtilis. The degradation of dextrose by C. albicans however, increased with dextrose concentration with average rate of 1.147-1.21% per hour. The degradations were gradually accompanied by increases in total acidity and decreases in pH of the dextrose solutions. The variation in the rates of degradation of dextrose by the test organisms is attributable to their survival rates in dextrose solutions and it is of great significance especially at the low inoculum size of 100 cells/ml. The results thus obtained necessitate the maintenance of a high level of aseptic procedures to prevent inadvertent contamination of i.v. fluids and other glucose containing solutions during clinical and other use conditions.