
Cannulas are most commonly used in hospitals to administer medication & contrast media or dyes, drain bodily fluid and supply oxygen to the body.
1. IV cannula: IV cannula is a flexible tube attached to a retractable needle inserted into the vein for administering medication.
2. Nasal cannula: The nasal cannula is used for oxygen supply through a thin hollow tube to the body via the nasal cavity.
Basic diagram of IV cannula

There are two types of IV cannulas
1. Peripheral IV cannula: Injected in a vein located at the extremities/limbs of the body
2. Central line IV cannula: Injected into major