Blood cultures are considered a complementary means of diagnosis for healthcare associated infections and are therefore the gold standard for diagnosing bacteremia. There are high contamination rates of blood cultures, especially in emergency departments, leading to risks for patients and hospital impacts. This study aims to analyze the effectiveness of the vacuum system with detour of the initial sample through the blood collection tube in reducing the contamination rate of blood cultures. This randomized clinical trial will target population will be patients from whom blood cultures are taken (at least 2 pairs) in all areas of the emergency department, except paediatrics. Two pairs of blood cultures will be taken, one using the traditional collection method and the other using the test method over a period of 3 months. The results will then be analyzed and the contamination rate of both methods extracted. The study aims to highlight an innovative system that is easy to apply technically, has a high cost-benefit potential and could have a significant impact on the quality of care, reducing healthcare-associated infections, increasing patient safety and reducing hospital costs.