A cannula is a tube that can be inserted into the body, often for the delivery or removal of fluid or for the gathering of samples. In simple terms, a cannula can surround the inner or outer surfaces of a trocar needle thus extending the effective needle length by at least half the length of the original needle.

What is a cannula in medical terms?

Cannula: A hollow tube with a sharp, retractable inner core that can be inserted into a vein, an artery, or another body cavity.

Why is a cannula used?

A cannula is a thin tube that doctors insert into a person's body cavity, such as their nose, or into a vein. Doctors use them to drain fluid, administer medication, or provide oxygen.