The latest edition of the University of Guelph Animal Health Laboratory’s newsletter contains an interesting report about 4 horses that died over the past few years from what was suspected to be contaminated intravenous fluid solutions. These cases were dead horses that were submitted for post-mortem examination from three different farms, so if anything, this could be an underestimation of the problem.
The first two horses were from the same farm. They were young Thoroughbreds that were routinely treated with intravenous electrolytes, vitamins and minerals (whether by the trainer or veterinarian is unknown). The first horse was found with its head hanging low after treatment. It later developed seizures and died. The second horse showed similar signs. The bacterium Klebsiella pneumoniae was isolated from a few different tissues of the first horse, as well as one of the "jugs" used to administer the fluids. The second horse had the same general lesions as the first, but Klebsiella wasn’t isolated; however, this may have been because the body wasn’t in great shape by the time it was submitted to the lab, and various other bacteria had overgrown the Klebsiella, making it difficult to isolate.
Another case was a young Standardbred that died after receiving intravenous fluids with vitamins, and a glyceryl guaiacolate jug. It had signs of bloodstream infection (septicemia) and Klebsiella oxytoca was isolated from multiple organs. Various bacteria were isolated from remnants of fluid in treatment bottles.
The final case was a five-year-old Standardbred that died after receiving a home-mixed vitamin jug. It had lesions similar to the other horses and consistent with a bloodstream infection. Klebsiella oxytoca was isolated from multiple organs.
Contamination of multidose drug vials or fluid solutions can occur if bacteria are inoculated into the bottle with a needle when a dose if withdrawn. We’ve shown this happens with multidose vials in a hospital situation, and of the farm it’s even more likely to occur because it’s a dirtier environment and, in the case of farm personnel, individuals have less experience with sterile technique. Fluid solutions can be contaminated in the same manner or when something is added to the fluids (e.g. vitamins). Contamination of reused fluid administration sets (i.e. fluid jugs/bags and the IV tubing) is quite likely, and that’s why use of sterlie, single-use administration sets is recommended. Adverse events from a little bit of contamination are uncommon, but as shown here, they can happen and they can be severe. There’s no information about what contributed to the contamination in these cases, but it’s almost certain that poor infection control practices were at the root of the problem. Trying to save money by skimping on sterilization, reusing items without proper care, and using poor hygiene practices in general can end up costing much more.