kanüül

Kanül, or cannula, is a small-diameter tube designed to be inserted into a body cavity, vessel, or duct to provide access for administration, drainage, or measurement. The term derives from Latin and is used in many languages, including Turkish, to describe a range of tubular medical instruments.

In medicine, cannulas serve diverse roles. Intravenous cannulas are inserted into veins to deliver fluids, medications, or blood products and to obtain venous access for sampling. Arterial cannulas allow continuous blood pressure monitoring and frequent blood gas analysis. Nasal cannulas deliver supplemental oxygen through the nostrils. Cannulas are also used in surgical settings, such as laparoscopic cannulas that create access ports for instruments, or chest drainage cannulas that remove air or fluid from the pleural space.

Design and materials vary by application. Cannulas can be soft and flexible or relatively rigid, and they are made from plastics such as silicone, polyurethane, or polyvinyl chloride. They may have different tip shapes, including blunt tips for gentle access and sharp tips for initial puncture in certain procedures. Sizes are standardized by gauge or French units, reflecting the intended use and patient age.

Safety and care are important considerations. Cannulas require sterile handling and proper placement by trained personnel to minimize infection, bleeding, or tissue damage. After use, disposables are typically discarded according to medical waste guidelines. While commonly associated with hospital care, cannulas also appear in home health, veterinary medicine, and various surgical disciplines.