American Medical Technologist (AMT) Practice Exam

What antiseptic is recommended for collecting a blood culture?

1. Alcohol swab

2. Iodine solution

3. Chlorhexidine gluconate

4. Hydrogen peroxide

The correct answer is: Chlorhexidine gluconate

Chlorhexidine gluconate is the recommended antiseptic for collecting blood cultures due to its broad-spectrum antimicrobial activity and residual effect. It is effective against a variety of bacteria, including both gram-positive and gram-negative organisms, and has some activity against viruses and fungi. This makes it a preferred choice for preventing contamination during blood culture collection. Chlorhexidine has a rapid action and remains effective for several hours after application, which is critical in the context of blood culture, where contamination can lead to false-positive results. Proper skin antisepsis using chlorhexidine can significantly reduce skin flora and the risk of introducing contaminants into the blood culture, ensuring that the results are accurate and reliable. Other antiseptics, while they may have some efficacy, do not provide the same level of effectiveness or residual activity. For example, alcohol swabs may not be as effective in killing certain bacteria and can evaporate quickly without leaving a long-lasting effect. Iodine solutions, while historically used, can also cause staining and may have some limitations regarding broad-spectrum efficacy. Hydrogen peroxide, while a strong antiseptic, can be cytotoxic and is not typically recommended for blood culture procedures due to its potential harmful effects on blood cells and possible reactions when mixed with blood