Are your hands clean enough for point-of-care electrolyte analysis?

Lam, Hugh S.; Chan, Michael H.M.; Ng, Pak C.; Wong, William; Cheung, Robert C.K.; So, Alan K.W.; Fok, Tai F.; Lam, Christopher W.K.

Summary Aim To investigate clinically significant analytical interference in point-of-care electrolyte analysis caused by contamination of blood specimens with hand disinfectant. Methods Six different hand hygiene products were added separately to heparinised blood samples in varying amounts as contaminant. The contaminated samples were analysed by three different blood gas and electrolyte analysers for assessing interference on measured whole blood sodium and potassium concentrations. Results There were significant analytical interferences caused by hand hygiene product contamination that varied depending on the combination of disinfectant and analyser. Small amounts of Microshield Antibacterial Hand Gel contamination caused large increases in measured sodium concentration. Such effect was much greater compared with the other five products tested, and started to occur at much lower levels of contamination. There was a trend towards lower sodium results in blood samples contaminated with Hexol Antiseptic Lotion (Hexol), the hand hygiene product that we used initially. Apart from AiE Hand Sanitizer, all the other hand disinfectants, especially Hexol, significantly elevated the measured potassium concentration, particularly when a direct ion-selective electrode method was used for measurement. Conclusion Hand disinfectant products can significantly interfere with blood electrolyte analysis. Proper precautions must be taken against contamination since the resultant errors can adversely affect the clinical management of patients.