Combining Cleaning and Disinfection – An Alternative Approach for Preventing the Contamination of Blood Products
Gatt N
Department of Applied Biomedical Science, Faculty of Health Sciences, University of Malta, Malta.
Gialanze, J.P.
National Blood Transfusion Service, Malta.
Spiteri, N.
National Blood Transfusion Service, Malta.
Zammit, V. *
Department of Applied Biomedical Science, Faculty of Health Sciences, University of Malta, Malta and National Blood Transfusion Service, Malta.
*Author to whom correspondence should be addressed.
Abstract
Aim: Disinfection products and protocols have been devised to provide safe blood and blood derivatives for transfusion; however, sepsis is still the leading cause of transfusion reaction fatalities. This raises the question whether disinfection on its own is sufficient for preventing such outcomes and whether cleaning of the arm prior to disinfection can further reduce the amount of skin commensals responsible for the contamination of blood products.
Methodology: One of the blood donor’s arms was disinfected according to the standard protocol and swabs were taken before and after disinfection (Scenario 1). The other arm was cleaned with a hypoallergenic soap-free and alcohol-free wipe and then disinfected (Scenario 2). Swabs from this arm were taken before cleaning, after cleaning and after disinfection. Tryptone soya agar plates were inoculated and incubated at a temperature which facilitates bacterial and fungal growth.
Results: A rate reduction was set and plates that failed this criterion were due to coagulase negative staphylococci. The commonest bacteria identified was Staphylococcus epidermidis. Less fungi were isolated on the after-disinfection plates that failed disinfection and these were Penicillium sp. and Cladosporium sp. Resultant colony counts from both Scenarios were statistically analysed and resulted in a significant reduction of bacterial colony counts post disinfection; however, the after disinfection plates of Scenario 2 had a lower average of colony counts than Scenario 1. Cleaning the skin prior disinfection resulted in a significant reduction of bacterial colony count and leading to a higher average of bacterial reduction in Scenario 2 than Scenario 1. Although Scenario 2 had a reduction rate of 98.3% which was more than that of Scenario 1 which had a reduction rate of 97.5%, there was no statistically significant difference (P=0.293) between the outcomes.
Conclusion: Cleaning the skin prior to disinfection reduces the bacterial load on the skin which makes the disinfection process more effective and reduces the probability of contamination of blood products.
Keywords: Blood transfusion, blood products, disinfection