When performing intravenous injections, why is it important to apply pressure to distend the vessel?

Applying pressure to distend the vessel is primarily important for making the vein more visible and easier to puncture. When pressure is applied, it causes the veins to fill with blood, leading to increased vascularization in the area. This increased visibility allows the technician to more easily identify the appropriate vein for injection, reducing the likelihood of multiple attempts and potential discomfort for the animal.

The process of distending the vein makes the anatomy clearer and allows for more precise needle placement, which can enhance the success rate of the procedure. In laboratory animal handling, minimizing stress and discomfort is crucial, and ensuring that the technician can consistently find and puncture veins effectively contributes to better overall outcomes in intravenous injections.