Laparoscopic trocar types, sizes and selection for hospital buyers

Trocar laparoscopy types: parts of a trocar

A laparoscopic trocar has two main parts: the obturator, which creates the passage, and the cannula or sleeve, which stays in the wound and holds the port. A valve at the head keeps the gas in, and a stopcock allows insufflation. The sleeve guides instruments in and out without losing the pneumoperitoneum created by the insufflator settings.

After the obturator is withdrawn, the sleeve remains as the working port. The seal, the length and the grip on the abdominal wall all influence handling, so ask surgeons to try samples.

Reusable and disposable trocars

A reusable trocar can be cleaned, inspected and sterilised many times; a disposable one is discarded after a single use. Reusable systems lower the cost per case when volumes are steady but require reprocessing capacity, inspection of seals and valves and a process for retiring worn parts. Disposable trocars cut reprocessing work and are always sharp and sealed, but add recurring cost and waste.

The reda laparoscopy range lists reusable trocar sleeves from 3.5 mm for paediatric use up to 20 mm, safety trocars with automatic locking and reducers, alongside autoclavable laparoscopes and modular instruments; see reda laparoscopy instruments for details.

Bladed, bladeless and optical trocars

Bladed trocars have a sharp cutting tip, and some include a shield that deploys after entry. Bladeless or dilating trocars separate the muscle fibres instead of cutting them, and their wound can be smaller. Optical trocars have a transparent tip that allows the telescope to be placed inside the obturator so the surgeon sees the abdominal wall layers during entry.

Surgical societies discuss the safest entry technique, and the choice depends on the patient and surgeon. Equipment buyers should offer a range, keep an inventory of each type and ensure that the telescopes in use fit the optical obturators.

• Bladed: sharp tip, often with a safety shield.
• Bladeless: dilating tip designed for less tissue cutting.
• Optical: transparent tip, allows visual entry.

The Hasson open technique and special trocars

The Hasson, or open, technique places the first port through a small incision under direct vision, using a blunt-tipped cannula that is anchored with stay sutures. It is common in patients with previous abdominal surgery and in many paediatric cases. A Hasson cannula is usually reusable and has a cone that seals the incision.

Other special items include trocars with a balloon or screw collar for fixation, reducers that allow a smaller instrument through a larger port and long bariatric versions. List them in your instrument sets so they are available when needed, using the guidance in our laparoscopic instruments list and names.

Trocar sizes and how to choose

Trocar sizes are given by the outer diameter, commonly from 3.5 or 5 mm up to 12, 15 and 20 mm. The 5 and 10 or 12 mm ports serve most standard instruments and telescopes; larger ports serve staplers, morcellators or specimen retrieval. Check the instrument diameter against the trocar size, because a mismatch leaks gas.

For a full instrument purchase checklist see the laparoscopic instruments buying guide. Beckfinity can prepare quotations for reda trocar and instrument sets; contact us through the contact page.