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

5 0 0 S E C T I O N V I • L I V E R

Once you establish safety, proceed with the resection. The Habib radio-frequency device may be used for division of parenchyma that is remote from major structures. During division of the parenchyma, you will visualize vascular and biliary structures. When size dictates, these may be divided between clamps and tied (Figure 46-8).

Along the line of demarcation, score the capsule of the liver anteriorly, using electrocautery. Then use a harmonic scalpel to carefully and sequentially divide the liver by layers. Do not permit yourself to establish a deep hole in the liver where control of hemorrhage will be greatly compromised.

During this dissection, divide major portal, arterial, and biliary structures between clamps and suture ligate using 3-0 silk suture ligatures. Slightly blunt clearing of surrounding flaky parenchyma may be achieved using a metal-tipped fine-tip suction apparatus, such as the Frazier tip instrument. As the dissection is carried toward the hilar structures, it is vital to recognize and avoid injury to the right hepatic vessels; failure to do so can result in ischemia of the right liver (see Figure 46-8).

At this point, no more than 0.5 to 2 cm depth of liver remains before you encounter the vena cava. Carry the dissection down to the vena cava, beginning in the inferior border of the liver. The left hepatic vein is typically situated at the diaphragmatic surface of the superior border of the left liver. Once again, note that at times the liver may be rotated, and what appears to be the left hepatic vein may be the middle hepatic vein. Do not divide the vein until all inflow has been reliably interrupted. Typically, the hepatic veins are not divided until the completion of the dissection. Thus stay alert for the identification of the left hepatic vein as the dissection is carried superiorly for the final 0.5 to 2 cm thickness of remaining left liver attached to the right liver (Figure 46-9).

Left hepatic vein

Harmonic

FIGURE 46–8

Left hepatic vein

Middle hepatic vein

Segment I

FIGURE 46–9

5 0 4 S E C T I O N V I • L I V E R

3. CLOSING

We close the fascia with an interrupted horizontal mattress suture (Smead-Jones) using heavy-gauge absorbable suture. The skin is reapproximated in the standard fashion.

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 means of 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 (alkaline phosphatase elevation) nor parenchymal cell death (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 of failure is inadequate liver remaining after resection. This can potentially resolve over time as the liver regenerates, which it will do to some degree. Support of the patient during this marginal period is vital.

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. 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.

STEP 5: PEARLS AND PITFALLS

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

If hemorrhage occurs during the procedure, one can compress the liver into the spine or into the right flank to gain control, and always call for assistance from another capable surgeon.

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 may occur from active draining of liters of fluid per day. In this setting, one must remove the drains (assuming they are not bile tinged) and suture the skin overlying the drain tract.

In recent years, there has been some enthusiasm for preoperative embolization of the portal vein on the side of the anticipated resection. This may offer some element of ischemia/ necrosis of the diseased liver and simultaneous regeneration of the opposite side.

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, 2007, pp 1341-1388.

2. Sugiyama M, Suzuki Y, Abe N, et al: Modified hanging maneuver with extraparenchymal isolation of the middle hepatic vein in left hepatectomy. J Hepatobiliary Pancreat Surg 2009;16:156-159.

3. Shirabe K, Shimada M, Gion T, et al: Postoperative liver failure after major hepatic resection for hepatocellular carcinoma in the modern era with special reference to remnant liver volume. J Am Coll Surg 1999;188:304-309.

C H A P T E R 47

DISTAL PANCREATECTOMY AND

SPLENECTOMY

William H. Nealon

STEP 1: SURGICAL ANATOMY

The term distal pancreatectomy and splenectomy typically refers to any resection beginning at approximately the level of the spine and moving toward the tail of the pancreas and the spleen. The associated anatomy includes the tail of the pancreas. This structure traverses the left lateral boundaries of the retroperitoneum and extends superiorly, finally ending toward the left hemidiaphragm. The tail fits into the concave area formed by the medial aspect of the spleen. The blood supply to the tail of the pancreas is provided by the splenic artery and vein.

The splenic artery (Figure 47-1) traverses the superior border of the body and tail of the pancreas. There are many small branches between the artery and the body and tail of the pancreas, which must be addressed should one choose to preserve the spleen after distal pancreatectomy.

The splenic vein is located on the posterior surface of the pancreas, and as it runs medially, it joins the superior mesenteric vein to form the portal vein. From the body of the pancreas out toward the tail, the splenic vein can be anticipated to maintain its position behind the body of the pancreas until it reaches the hilum of the spleen. Once again, very small tributaries will likely be encountered between the body and tail of the pancreas and splenic vein—these must be addressed should one choose to preserve the spleen during a distal pancreatectomy.

The spleen is attached on its lateral and superior borders to the retroperitoneum, connecting the peritoneal serosa to the visceral serosa. Posterior to the spleen and the tail of the pancreas is the left kidney and the left adrenal gland. These may be encountered during dissection. The stomach is situated anterior to the body and tail of the pancreas, and there are vascular branches between the fundus of the stomach and the spleen. These vessels are termed “short gastric vessels.” The transverse colon and, in particular, the transverse mesocolon may be apposed to these tissues, and the dissections of these structures away from the spleen and the body and tail of the pancreas are necessary to complete the resection. The splenic flexure of the colon typically will be mobilized during this dissection (see Figure 47-1).

508