What is a primary risk of using a small gauge needle?

The primary risk of using a small gauge needle is that it can lead to hemolysis of the sample. Hemolysis occurs when red blood cells are damaged or destroyed, releasing hemoglobin into the plasma. This can happen with smaller gauge needles due to increased turbulence and shear stress as blood flows through a narrower lumen. The more limited diameter can create higher pressure and cause trauma to the fragile red blood cells as they pass through, especially if the blood is collected too forcefully. Hemolysis can adversely affect test results, potentially leading to misinterpretation of laboratory values.

In contrast, while it is sometimes thought that smaller needles might reduce the sensation of pain for the patient, the more significant concern in terms of sample integrity is the risk of hemolysis. The other provided options do not align with this increased risk and highlight different aspects of blood collection, but they do not address the critical impact on sample quality that hemolysis represents.