Influence of production environment on sterility of parenteral nutrition admixtures at Ramathibodi Hospital

Abstract

The purpose of this study was to investigate the contamination rate of parenteral nutrition (PN) prepared from the cleanroom compared with the traditional separated room. Cost and unit cost analyses were also compared. The study was divided into 3 parts. Firstly, validation of sterile area was conducted by placed Tryticase Soy Agar (TSA) plates in various position in laminar air flow hood (LAFH) and admixing area. Secondly, systematic sampling of final product was used for sterility test. Lastly, cost and unit cost of PN were analyzed by total direct cost calculation. Each preparation site was tested for 8 weeks. The results of validation of sterile area revealed that 70 plates (48.61%) from the separated room were found microorganism growth in different days and locations. There were 14 plates (9.72%) from the cleanroom found microorganism growth. The results showed significant difference (p<0.001). The sterility test showed that 7 out of 748 samples of PN prepared from the separated room were contaminated, and there was no microorganism found in PN prepared from the cleanroom, resulting in significant difference (p=0.008) of sterility between PN prepared from 2 different environments. Types of microorganisms in final products were similar to types of microorganisms found in the preparation area in that period, which was assumed a strong relationship between preparation environment and sterility of final products. Cost analysis showed that the unit cost of PN prepared from the cleanroom was greater than PN prepared from the separated room. Because the cleanroom was provided with a complex system for maintaining air cleanliness standard. It was concluded that the superior air cleanliness provided by cleanroom system can deliver a good quality of PN without microbiological contamination. Although the preparation cost was higher, but patient safety, which was invaluable, must be the first factor in any consideration.