Atlas of General Surgical Techniques (Courtney M. Townsend Jr., B. Mark Evers)

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3. CLOSING

Close the abdomen in a standard manner. We favor Smead-Jones closure with heavy-gauge absorbable suture.

STEP 4: POSTOPERATIVE CARE

In the first 24 hours after surgery, the primary concern is hemorrhage and the related measure of coagulation status. These should be monitored by serial measurement of hemoglobin and coagulation factors.

In all major resections, particularly in patients with cirrhosis, one must be vigilant for any signs of hepatic failure. A particularly ominous finding is the progressive rise in bilirubin level with an enzyme pattern that supports neither obstruction nor parenchymal cell death, such as transaminase elevations. The most ominous finding is a plummeting serum glucose level, which reflects the loss of glycogen stores in the liver and by inference the loss of viable liver. Unfortunately, there is little one can do to reverse this pattern of failure. One possible cause is inadequate remaining liver after resection. This can resolve over time as the liver regenerates, which it will do to some degree.

One possible remediable cause of this progressive demise is thrombus formation in the portal vein. This would seem to be unlikely, because coagulation is typically inadequate in these patients, but we have seen this phenomenon. It is possible that lysis of this clot may restore vital flow.

Sepsis is particularly metabolically taxing to the liver. In the compromised postoperative liver, sepsis can be catastrophic, and one should monitor and obtain cultures if necessary to prevent infectious processes from progressing.

Ascites may form, and one must be aware when this phenomenon has occurred and treat as one would normally treat this entity with careful and judicious use of salt-containing intravenous fluids and with diuresis.

Remove drains if no bile is seen in the effluent.

One preoperative option, which was originally developed for cirrhotic patients with what appeared to be inadequate functional reserve but later applied to all candidates, is embolization of the portal vein. In this manner some degree of the regeneration of lost liver takes place before the stress of surgery is added.

STEP 5: PEARLS AND PITFALLS

As with all major operative procedures, one must be extremely careful with patient selection.

If hemorrhage occurs at any time during the procedure, the liver can be compressed into the spine or into the right flank to gain control, and another capable surgeon can be called for assistance.

Before dividing any of the major vascular structures, stop and reconfirm that the proper structure is being divided.

If ascites forms and the drains are still in place, excessive electrolyte and fluid loss can occur through actively draining liters of fluid per day. In this setting, the drains (assuming they are not bile tinged) should be removed, and the skin overlying the drain tract should be sutured.

SELECTED REFERENCES

1. Blumgart LH, Belghiti J: Liver resection for benign disease and for liver and biliary tumors. In Blumgart LH (ed): Surgery of the Liver, Biliary Tract and Pancreas, 4th ed. Philadelphia, Saunders Elsevier, 2007, pp 1341-1388.

2. Liu CL, Fan, ST, Cheung ST, et al: Anterior approach versus conventional approach right hepatic resection for large hepatocellular carcinoma: A prospective randomized controlled study. Ann Surg 2006;244: 194-203.

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Lymphovascular and biliary structures enter the liver through the hepatoduodenal ligament that courses between the duodenum into the base of segments IV and V, which is termed the porta hepatis. The portal triad of microanatomy is matched by the gross anatomic orientation in the hepatoduodenal ligament—composed of hepatic artery, portal vein, and bile duct. Each structure divides into a left and right branch and then arborizes within the liver in a pattern defined by the segments (see Figures 46-1 and 46-2).

Venous drainage of the liver is primarily located at the superior aspect of the liver in the midline in short structures between the vena cava and the liver. The left, middle, and right hepatic veins each enter the vena cava within 2 to 4 cm of one another in a coronal orientation. One or all of these venous elements may be intrahepatic or may have exceedingly short extrahepatic components. This anatomic feature raises considerably the risk of uncontrolled hemorrhage during dissection and resection (see Figure 46-2). In addition to these three venous structures, there are between 2 and 20 tiny tributaries between the posterior surface of the liver and the contiguous vena cava. These must be divided to fully mobilize the right liver.

INDICATIONS

Left hepatic lobectomy is performed primarily for the treatment of malignant disease, which includes hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and a variety of metastatic lesions—most commonly of abdominal origin. The best outcomes are achieved in patients with metastatic lesions from carcinoma of the colon and rectum.

However, the procedure is also performed for benign diseases, such as cystadenoma of the liver, giant hemangioma of the liver, and intrahepatic biliary strictures existing primarily on the left side of the biliary tree, and at times for lesions such as either hepatic adenoma or focal nodular hyperplasia determined to be clinically significant, perhaps because of increasing size.

STEP 2: PREOPERATIVE CONSIDERATIONS

Due to the magnitude of hepatic surgery, one first consideration is the medical status of the patient and likely risk of surgery. Thus one must exclude significant coronary, pulmonary, or renal disease or age and frailty. Of particular concern in relation to hepatic surgery is the underlying hepatic function. Because hepatocellular carcinoma is associated with prior hepatitis and cirrhosis, one must determine first whether cirrhosis exists and second what level of function is apparent. Historically, this was measured by examining synthetic and excretory functions and measures of portal hypertension (serum albumin level, coagulation profile, serum bilirubin level, ascites, and mental status/serum ammonia). More recently, the Model for End-Stage Liver Disease (MELD) score was developed as a means of segregating candidates for liver transplant. This system incorporates prior variables but has added and places considerable significance to renal function. Particularly when one anticipates a major resection one must establish that sufficient liver will remain to support life. Unfortunately, this estimate of “hepatic reserve” is even today an inexact science.

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2. DISSECTION

Divide the falciform ligament and leave a 2-0 silk suture as a stay suture, and then place a hemostat on the silk suture. Carefully incise the avascular plane extending from the falciform ligament back toward the diaphragm using electrocautery after placing the right hand beneath the left lobe of the liver (Figure 46-4). In a similar manner under direct vision, incise the left triangular ligament using electrocautery by first cauterizing the anterior leaflet of the left triangular ligament. Second, take the posterior leaflet of the left triangular ligament over toward the vena cava. Anticipate, possibly visualizing, the left hepatic vein as the dissection carries close to the vena cava and carefully monitor to prevent any injury to the left hepatic vein. Carefully divide some of the fiber attachments between the diaphragm and the superior border of the liver, where the falciform ligament has inserted, and begin to visualize the vena cava and possibly visualize the middle and left hepatic veins (Figure 46-5).

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Place a Rummel loop surrounding the portal triad by incising the peritoneum just medial to the hepatoduodenal ligament. By passing the left hand into the foramen of Winslow, you pass an umbilical tape. This tape is grasped and placed in the hook device, and the umbilical tape is passed through a section of rubber tubing (Figure 46-6). Use this step in the event that uncontrolled hemorrhage is encountered during the resection. At this point it is occasionally necessary to use ultrasound for two reasons:

To establish that the anticipated line of resection includes the lesion you want to resect

To visualize intrahepatic vascular structures, particularly hepatic venous and intrahepatic portions of the portal venous system (see Figure 46-6)

Next, direct attention to the hepatoduodenal ligament where you must separately identify each of the three major components of the ligament, which include the following:

Common bile duct

Proper hepatic artery

Portal vein

Encircle the common bile duct with a 1⁄4-inch Penrose drain. Then encircle the proper

hepatic artery using vessel loops. By placing lateral traction on the bile duct and medial traction on the artery, you will expose the portal vein, which is situated between these two structures in a slightly deeper plane. By gently teasing the tissues toward the hilum following a horizontal plane along the base of segment IV, you will lower the falciform plate. This provides visualization of the left structures of the portal, arterial, and biliary systems (Figure 46-7).

Establish an acceptable length on each of these structures to ensure careful and safe division.

Divide the left hilar structures sequentially. Divide the left hepatic duct. You must use nonabsorbable suture, either 3-0 or 4-0 Vicryl or polydioxanone (PDS). Divide the left hepatic artery between clamps and suture ligate using 3-0 silk suture ligature. Divide the portal vein between clamps. Sew the stump of the left portal vein with a continuous running 4-0 Prolene suture (see Figure 46-7).

After division of all of the left hilar structures, a clear line of demarcation will be seen with purple discoloration of the anatomic left liver. The demarcation crosses the gallbladder bed from anterior to posterior.

In patients who still have a gallbladder, perform a cholecystectomy in the normal fashion.

Encircle the left hepatic vein with a vessel loop. It is important to note that at times, with varying sizes of the liver, the left hepatic vein may be situated in a more lateral and inferior location than you might anticipate, and it is vital to establish whether the vein that is first seen in the dissection along the diaphragm is not the middle hepatic vein. It is also vital that you not sacrifice the middle hepatic vein if it is not necessary to do so. Do not divide the hepatic veins until you complete the dissection. However, establish some control of the vein by encircling it.