Cannula
（重定向自Cannulae）
![Intravenous cannula](/Images/godic/202501/03/Venflon_intravenous_cannula_20147.jpeg")
![Drawing of a nasal cannula](/Images/godic/202501/03/Nasal_cannula0147.png")
![Air sensitive cannula used in synthetic chemistry.](/Images/godic/202501/03/Air_sensitive_cannula_-_syringe_valve_10147.png")
A cannula (from Latin "little reed"; plural cannulae or cannulas) is a tube that can be inserted into the body, often for the delivery or removal of fluid or for the gathering of data. 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.