Blood cultures

Emergency medicine, Hospital-wide, Internal medicine

Blood cultures

Emergency medicine, Hospital-wide, Internal medicine
Blood cultures are the golden standard to reveal the presence of bacteremia (bacteria in the bloodstream). In current practice, only 7.5% of blood cultures are positive, thus showing that there is great room for improvement.

Despite the little amount of evidence regarding its effectiveness, blood cultures are often taken when a rise in a patient’s temperature is observed. In a recent study, 3890 blood culture tests over a period of 7 months were analyzed. The analysis showed that only in 13.9% of the cases the blood culture tested positive for the presence of one or more micro-organisms. Almost half of the positive tests (46.4%) were contaminated, indicating that only 7.5% of the tests truly tested positive. The number of positive blood cultures was observed to be higher in the emergency department. The number of positive blood cultures also showed to be higher when these were taken within 24 hours of hospital admission of the patient. Based on this high negative percentage, we can conclude that the indication for blood cultures could be improved and the number of unnecessary blood cultures could be decreased. The method through which the blood culture is collected will also be targeted for improvement in an effort to prevent contamination. Contamination of blood cultures results in repetition of the procedure and thus unnecessary treatments with antibiotics and higher costs. The project aims to achieve a 10% reduction in the total number of blood cultures.

‘It predominantly revolves around doing that what’s good for the patient and leaving out what’s unnecessary’

                       (from interview with Marlou)


The project team will use several different strategies to reduce the number of blood cultures taken. These strategies will entail education, adjustment of protocols, feedback regarding progress, training employees regarding the prevention of contamination, and changes in the ordering system.


Planned duration: 1 year.

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Prof. Prabath Nanayakkara, MD, PhD

| Amsterdam Universitair Medische Centra, locatie VUmc