How can dehydration affect blood sample collection?

Dehydration significantly impacts blood sample collection by causing veins to become less prominent and blood to become more viscous. When a person is dehydrated, the overall volume of blood decreases as the body loses fluid, which can result in the collapsing or narrowing of veins. This makes it more challenging for healthcare professionals to locate veins for venipuncture and may require multiple attempts to collect a sample.

Additionally, the viscosity of blood increases when someone is dehydrated. Thicker blood can lead to slower flow rates during collection, potentially making the process more difficult. This heightened viscosity can complicate not only the collection but also subsequent analyses, as it can affect the accuracy of certain tests that rely on blood fluidity.

These factors illustrate why proper hydration is essential prior to blood sample collection, influencing both the ease of the procedure and the quality of the sample obtained.