CHOLECYSTECTOMY

Open Cholecystectomy

EMBRYOLOGY

The liver diverticulum is derived from the distal end of the foregut and grows into the septum transversum. The connection between the hepatic diverticulum and the foregut (which develops into duodenum) elongates and narrows to form the bile ducts. The gallbladder and the cystic duct develop from a ventral outgrowth that emerges from the bile duct. The biliary tree passes through a solid stage that is followed by recanalization. The gallbladder initially is a hollow organ but becomes solid due to proliferation of epithelial cells. Later, recanalization occurs, and failure of this process leads to atresia of the gallbladder.

RELEVANT SURGICAL ANATOMY

The gallbladder is a pear-shaped organ about 7.5 to 10 cm in length. It lies within a fossa on the inferior aspect of the right lobe of the liver. Anatomically it can be divided into a fundus, body, infundibulum, and neck. The fundus extends beyond the edge of the liver and comes in contact with the anterior abdominal wall at the level of the tip of the ninth rib. The infundibulum sags down toward the duodenum at Hartmann’s pouch, where gallstones often become impacted. Originating from the neck of the gallbladder is the cystic duct, which joins the common hepatic duct in a variable fashion. The surgically important triangle of Calot is formed by the common hepatic duct on the left, the cystic duct on the right, and the liver above.

The common hepatic duct is formed by the union of the right and the left main bile ducts outside the confines of the liver. It is 2 to 3 cm long and lies entirely within the portal fissure. The common bile duct (CBD) is formed by the union of the common hepatic duct and the cystic duct. It measures approximately 8 cm in length (range, 5–15 cm), and its course is as follows:

Behind the head of the pancreas the CBD is joined by the main pancreatic duct to form a common channel known as the ampulla of Vater. The ampulla opens on the posteromedial aspect of the second part of the duodenum. This opening, known as the duodenal papilla, is located approximately 10 cm from the pylorus. This papilla will normally allow passage of a 3-mm dilator. On cholangiography the normal diameter of the CBD ranges from 8 mm to 1 cm, whereas on ultrasonography it is 6 cm.

The blood supply of the gallbladder is derived from the cystic artery, which is most commonly a branch of the right hepatic artery, and lies within the triangle of Calot. The cystic artery tethers the gallbladder and can be felt as a taut string when the gallbladder is retracted laterally. The blood supply of the extrahepatic bile ducts originates from the superior pancreaticoduodenal artery, hepatic artery, and cystic artery. The veins from the gallbladder drain directly into the liver or into the hepatic vein via the pericholedochal plexus.

The foramen of Winslow is an important anatomic landmark for performing the Pringle maneuver. Its relations are as follows: (1) anteriorly, the free border of the lesser omentum; (2) posteriorly, the inferior vena cava and the right adrenal gland; (3) superiorly, the caudate process of the liver; and (4) inferiorly, the horizontal part of the hepatic artery and below it the second part of the duodenum.

PREOPERATIVE PREPARATION

Apart from assessment of the cardiopulmonary systems to evaluate the patient’s ability to withstand open cholecystectomy, special circumstances should be addressed. If the patient is jaundiced, in addition to the baseline laboratory investigations, liver function tests, hepatitis profile, and a coagulation profile should be obtained. If there is a history of fluctuating jaundice in male patients, Gilbert disease must be excluded. If endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography has been performed, the results should be reviewed.

Prophylactic antibiotics should be administered, especially for high-risk patients with the following parameters: age older than 70 years and a history of diabetes mellitus, jaundice, CBD stones/stricture, biliary tree malignancy, or steroid usage.

Operative Procedure

POSITION

The patient undergoes general anesthesia with endotracheal intubation. A nasogastric tube is inserted. The patient is placed in a supine position on an x-ray operative table and arranged for ultra-operative fluoroscopy. The patient is prepped and draped. The surgeon should stand on the right side of the table.

INCISIONS

If it is an elective procedure and no other pathology is suspected, it would be appropriate to use a Kocher (oblique right upper quadrant) incision. If on laparotomy other pathology is discovered, a Kocher incision can be extended into a bilateral subcostal incision.

Kocher Incision

A subcostal incision is made. The anterior rectus sheath is incised and the rectus muscle identified. A Rochester-Pean clamp is placed under the muscle, which is divided with electrocautery. The assistant should be ready to clamp epigastric vessels within the rectus muscle, and these vessles are ligated with 2-0 silk sutures. Next, the posterior sheath is incised, and the preperitoneal fat is separated digitally or with hemostats. The peritoneum is grasped with two hemostats and incised to open the peritoneal cavity. The falciform ligament can be spared if the exposure is adequate, but in most cases it is divided and ligated with 2-0 absorbable sutures.

Midline Incision

The linea alba, identifiable by the crisscrossing of the fascial fibers, is incised, and the preperitoneal fat is identified. The peritoneum is grasped up with two hemostats and incised after it has been ensured that no bowel has been inadvertently included with the peritoneal lining. The opening is extended with the use of electrocautery.

EXPOSURE AND OPERATIVE TECHNIQUE

First, a careful exploration is performed to exclude unrecognized pathology, with special reference to “Saint’s triad,” which is defined by the presence of gallstones, hiatus hernia, and diverticular disease. Other common causes of upper abdominal pain that should be excluded include peptic ulcer, carcinoma of the stomach, carcinoma of the pancreas, and chronic pancreatitis.

Exposure of the gallbladder is achieved through the following steps:

The above steps are extremely important in facilitating the remainder of the procedure.

Any adhesions present between the gallbladder and the adjacent structures are carefully and sharply divided. The cystic duct and the gallbladder are gently palpated to feel for any stones. The operator should avoid inadvertently dislodging any stones into the CBD. After Hartmann’s pouch has been identified, it is grasped with a Rochester-Pean clamp and retracted laterally to place the cystic duct on tension. An additional Rochester-Pean clamp is placed near the fundus to provide traction during dissection. The assistant should retract the duodenum downward to place the CBD on tension. This greatly facilitates the dissection that needs to be performed in Calot’s triangle. If there is evidence of intense inflammation or fibrosis in this area, inadvertent injury to the structures within the porta hepatis may occur. In this situation it is wise to first perform the cholecystectomy in the retrograde fashion, where the gallbladder is dissected from its bed, until the cystic duct is clearly identified. Dissection should be undertaken close to the gallbladder wall to avoid injury to the right hepatic artery, right hepatic duct, or CBD.

fig: The gallbladder is grasped with two clamps and retracted laterally to expose the triangle of Calot.

In the absence of such inflammation, the peritoneal reflection over Calot’s triangle is incised gently and reflected toward the liver. The peritoneum is bluntly dissected off the ducts in two opposing directions using a Kittner dissector. It is preferable not to use sharp dissection in this area. By using blunt dissection the cystic duct is identified and the junction between the cystic duct and the CBD is clearly displayed.

Next, the cystic artery is identified and traced down toward the gallbladder. Any vessel that is more than 2 mm in diameter may be the right hepatic artery and therefore should be clearly identified as the cystic artery before division. The cystic artery is dissected free with a right-angle Mixter clamp and doubly ligated with 2-0 absorbable sutures. Alternatively, if the access is difficult, hemoclips can be used. In the event of bleeding from the area of the porta hepatis, avoid blind clamping and instead perform the Pringle maneuver. This maneuver involves passing the forefinger and the middle finger of the left hand through the foramen of Winslow, with the thumb placed anteriorly to compress the hepatic artery within the free edge of the lesser omentum.

Next, an operative cholangiogram is performed. Using a right-angle Mixter clamp, two 2-0 silk ligatures are placed around the cystic duct. The proximal ligature is tied down and held with a hemostat for retraction. One throw of a knot is loosly placed on the distal ligature and held with a hemostat. With Metzenbaum scissors an oblique incision is made in the cystic duct. Patency of the cystic duct is checked with a lacrimal duct probe, which also assists in dilating the valves of Heister, if present. A sample of the bile is sent for culture. A small cholangiocatheter is placed through the aperture while flushing with saline to prevent entry of air bubbles. Now the previously placed distal silk ligature is tied down to secure the catheter. The syringe containing the contrast material is attached to the cholangiocatheter. To prevent entry of air bubbles, the tip of the cholangiocatheter should be below the level of the CBD, and in this position bile should be seen flowing out of the catheter. Next, all the instruments and sponges are removed from the operative field because these can obscure the cholangiogram. With the operating table tilted 10 degrees to the right side, two radiographs are obtained, one after 5 mL and the other after 10 mL of the dye is injected.

The features examined in an operative cholangiogram are