Basic Principles Of Laparascopic Surgery

The creation of a pneumoperitoneum is the first step in any abdominal laparascopic surgery. This can either be done using a veress needle or a subumbilical incision. The former uses a small needle-loaded needle which is pushed through the skin and subcutaneous tissue. Once the needle pierces the peritoneum, there is no longer any resistance thus the spring activates and retracts the needle automatically. This in theory avoids damage to intra-abdominal organs. CO2 is the pumped into the peritoneal space and a camera is inserted. The rest of the ports can be inserted under direct vision. The second approach involves the use of a small subumbilical incision and blunt dissection to gain entry into the peritoneum. A 5mm or 10mm port is then inserted. Through the port CO2 is placed into the peritoneum which causes it to lift up like a dome above the organs. This creates a space so that the organs can be seen and manipulated. The images from the camera are then projected onto a 2-D camera. More ports are usually needed for instruments and these are now inserted under direct vision.

There are many technical challenges involved in laparascopic surgery. One of these is overcoming the fulcrum effect. This phenomena means that the deeper your instrument is into the abdominal cavity (i.e. further away from your port), the greater the magnification of small movements and vice versa. The surgeon must always be aware of the fulcrum effect as accuracy is reduced by it and inadvertent large movements at depth may result in accidental damage to organs. Another challenge is the difficulty in depth perception. This is due to the fact the images are beamed onto a 2-D display. The surgeon can use a number of ways to judge depth this including light and shade, size of objects in relation to each other and distance away from the tip of his/her instruments. Lack of tactile perception and the fact that the visual field is dependent on the assistant manipulating the camera are two important drawbacks to laparascopic surgery.

Instruments

Ports

These come in various lengths and sizes. The camera port also has a pipe to connect gas to in order to insufflate the abdomen.

Camera

Again these come in various sizes and needs to be inserted into the correct size port or if the port is larger, then a convertor can be used. The assistant manipulates the camera and must aim to have the surgeons working field centred at all times. Being the camera operator is not a passive job and needs a lot of focus as well as anticipation. The camera also contains buttons to allow image capture.

Graspers

Maryland and Johanne are most commonly used. These allow the surgeon to grasp the organ in question and manipulate it. In lap chole they can also be used to dissect the adhesions around the gall bladder and Calot’s triangle. They may also be connected to diathermy.

Scissors

Many different types are available. These are used in lap chole to cut the cystic duct and artery after the clips are applied.

Diathermy

These can be connected to the ends of scissors or graspers or it maybe used in isolated form such as the hook diathermy.

Clips

These may be plastic or metallic and are used to ligate the cystic artery and duct to avoid bleeding & bile leak.

Suction

If any bile has leaked or some bleeding occurred then washout and suction are used.

Bag

These include EndoCatch™ and are small bags that open inside the peritoneum and enclose the gallbladder. They are then removed with the contents through the camera port under camera vision.

 

 

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