trocar

A trocar is a medical instrument consisting of a sharp-pointed obturator that fits inside a hollow tube called a cannula. It is used to puncture a body cavity and create a passage through which other instruments or drains can be introduced. After access is gained, the obturator is removed, leaving the cannula in place to maintain a working channel.

Trocar designs vary, including sharp-tipped and blunt-tipped types, single-use disposable trocars, and reusable variants. Some trocars incorporate safety features such as retractable tips, valves, or seals to reduce gas leakage and tissue injury. The size of a trocar is chosen to fit the intended procedure and instrumentation.

In modern surgery, trocars are most commonly used to gain access for laparoscopy and other minimally invasive procedures. A sequence typically involves creating an entry point in the abdominal wall and inserting a cannula to establish a working channel for a laparoscope and surgical instruments. The first access can be achieved with an open (Hasson) technique or with a Veress needle to insufflate the abdomen before trocar insertion.

Safety and technique are central considerations, as trocar use carries risks of injury to abdominal organs, blood vessels, or immerging structures. Careful technique, patient positioning, controlled entry, and consideration of alternative methods (such as blunt-tipped or shielded trocars) help mitigate complications. Proper post-entry checks are performed to confirm proper placement and adequate pneumoperitoneum or cavity access for the planned procedure.