The 16-Gauge Needle: Size Matters

Donors often look at the needle and gasp. "It's so thick!" (It's a 16-gauge). Why can't we use a thin injection needle?

The Physics of flow

1. Speed: We need to collect 450ml in less than 10-12 minutes. Any slower, and the blood starts clotting in the tube.
2. Shear Stress: Red blood cells are delicate. Squeezing them through a tiny needle at high speed would crush them (Hemolysis).

Don't worry, the medical staff at **Sarva Jeevanseva Foundation** are experts at making the pinch minimal.