Brendan J. Boland
Andrew S. Klein
Presentation
A 55-year-old man with a history of chronic hepatitis C infection is brought into the emergency department after several bouts of hematemesis at home. His family says that he repeatedly vomited a large amount of dark red blood and had not been feeling ill before the hematemesis. His blood pressure is 80/40 mm Hg, and his heart rate is 108 beats per minute. He is awake and responsive but appears confused. Physical examination reveals slight scleral icterus, a mildly distended but soft abdomen, and splenomegaly.
Differential Diagnosis
Gastroesophageal varices should be the first consideration in the patient with an upper gastrointestinal bleed and a documented history of liver disease. About half of patients with cirrhosis have varices, and the risk of developing varices increases with evidence of hepatic decompensation. Varices are a direct consequence of portal hypertension. They can develop throughout the length of the gastrointestinal tract but most commonly are detected at or just proximal or distal to the gastroesophageal junction. Variceal bleeding is a particularly lethal complication of portal hypertension. The 6-week mortality after an episode of bleeding exceeds 20%.
Bleeding from gastroesophageal varices typically is brisk and classically presents with effortless, recurrent hematemesis, melena, or both. Varices should be strongly suspected as a source in any patient with history or stigmata of liver disease. Clinical exam signs may include jaundice, spider angiomata, palmar erythema, caput medusae, splenomegaly, and/or ascites. A Mallory Weiss tear or severe esophagitis can present similarly, and both are common in patients with heavy alcohol use; however, the bleeding is usually less severe and self-limited. Peptic ulcer of the duodenum or stomach is the single most common cause of severe upper gastrointestinal bleeding and needs to be a consideration even in the patient with liver disease. A history of dyspepsia, infection with Helicobacter pylori, or nonsteroidal anti-inflammatory drug use are risk factors for ulcers. Regardless of the cause of bleeding, the initial goals are the same—resuscitation and endoscopy for diagnosis and treatment.
Soon after arrival in the emergency room, the patient becomes increasingly confused. His disorientation progresses rapidly to somnolence and he is difficult to arouse with verbal stimulation.
Workup
Securing the patient’s airway is particularly important in the setting of the moderate-to-severe encephalopathy that should be suspected clinically. Endotracheal intubation prevents aspiration of blood and gastric contents and ensures a stable airway for endoscopy. Resuscitation should begin concurrently with placement of multiple large caliber venous catheters either peripherally or centrally. Blood tests should include a complete blood count, serum electrolytes, a liver profile, and a prothrombin time to rule out the presence of thrombocytopenia, coagulopathy, electrolyte abnormalities, or renal dysfunction that frequently occur in cirrhotic patients in the setting of acute hemorrhage. Blood and blood products (fresh frozen plasma and platelets) are transfused as indicated, but over transfusion should be avoided as elevated systemic venous pressure increases the risk of variceal bleeding. A hemoglobin level of approximately 8 to 10 g/dL is ideal.
Endoscopy
The cornerstone of the initial workup is endoscopy and should be done within 12 hours of admission. When varices are identified, endoscopic ligation (banding) is the preferred treatment. The varix is suctioned into a channel in the endoscope and a band is deployed, strangulating the varix and causing thrombosis. If banding cannot be performed for technical reasons, endoscopic sclerotherapy with a chemical sclerosant such as sodium tetradecyl sulfate, sodium morrhuate, ethanolamine oleate, or absolute alcohol can be attempted.
Presentation Continued
The patient is stabilized hemodynamically and undergoes esophagogastric endoscopy. He is found to have actively bleeding grade III esophageal varices that are successfully banded. There is evidence of moderate portal hypertensive gastropathy. His hemoglobin is 8 g/dL and his INR is 1.8.
Diagnosis and Treatment
Pharmacologic Treatment
Pharmacologic therapy with a splanchnic vasoconstrictor is initiated during the initial resuscitation. Vasopressin is a potent vasoconstrictor and effectively lowers portal pressure but is associated with multiple side effects including peripheral, cardiac, and mesenteric ischemia. Terlipressin is a synthetic analogue of vasopressin that has been shown to reduce mortality in acute variceal bleeding with significantly fewer side effects, but is not currently available in the United States. Octreotide, a somatostatin analogue, is safe and widely available and is currently considered the pharmacologic treatment of choice for most cases of acute variceal bleeding (Table 1).
TABLE 1. Pharmacologic Treatment of Bleeding Gastroesophageal Varices
Prophylactic antibiotics have been shown to lower mortality and should be administered. Norfloxacin given orally is the first-line recommendation, but oral intake is usually impractical in the acute setting, and ciprofloxacin or levofloxacin can be given intravenously. Ceftriaxone has been shown to be superior to norfloxacin at preventing bacterial infection in patients with more advanced cirrhosis.
Transjugular Intrahepatic Portosystemic Shunts
Combination endoscopic and pharmacologic therapy controls bleeding in 80% to 90% of patients. Nonresponders may be treated with portosystemic shunts. These procedures create a connection between the portal and the systemic venous circulations, thereby decompressing the hypertensive portal circulation. Transjugular intrahepatic portosystemic shunt (TIPSS) is an interventional radiologic procedure that creates an intrahepatic fistula between a branch of the portal vein and a hepatic vein. A stent graft is then deployed, maintaining the connection. It successfully controls bleeding in over 90% of patients that fail first-line therapy but has a high rate of stenosis that requires frequent monitoring and reintervention (up to 80%). The use of covered stent grafts shows promise in significantly reducing the rate of stenosis. As TIPSS lowers the portal–systemic venous pressure gradient, it also can control refractory ascites and is often used in the elective setting for this purpose.
Balloon Tamponade
Balloon tamponade is an important temporizing tool in the refractory case or as a bridge to definitive therapy, but its use is associated with potentially fatal complications including esophageal/gastric necrosis or perforation, particularly when inserted by inexperienced personnel.
Surgical Approach
With the advent of TIPSS, the use of surgical shunts in the setting of acute bleeding has diminished. However, surgical shunts continue to have a role when lack of local expertise or technical issues make TIPSS impossible. Since long-term surgical shunt patency surpasses that of TIPSS, the former may be preferable when continuing follow-up is problematic. Liver transplantation is the preferred therapy for patients suffering from the complications of portal hypertension who also have decompensated hepatic function. In this instance TIPSS, not surgical shunt, is generally preferred to control the portal hypertension as a bridge to ultimate liver transplantation.
Portocaval Shunts
There are two types of surgical shunts: selective, which preserve prograde flow through the portal vein to the liver, and nonselective, which divert all portal flow to the systemic circulation. The prototypical nonselective shunt is the side-to-side portocaval shunt. Because they completely bypass the liver, nonselective shunts have the drawback of possibly worsening or causing encephalopathy. They are, however, a good treatment for ascites as they decompress the portal vein and the hepatic sinusoids. Portocaval shunts may create significant technical challenges for patients who ultimately require liver transplantation. The porta hepatis becomes a reoperative field at the time of transplantation, and dismantling the portocaval shunt can be problematic for even the most experienced surgeon. In patients who may eventually undergo liver transplantation, who fail TIPPS, the mesocaval shunt using an interposition graft is preferred (see below). The only truly selective shunt is the distal splenorenal shunt. It maintains antegrade flow through the portal vein and decompresses gastroesophageal varices through the short gastric, left gastroepiploic and splenic veins into the systemic venous drainage of the left renal vein. As no portal blood is diverted to the systemic circulation, encephalopathy is not a consequence. It has no effect on ascites and therefore is a poor choice in patients where this is an issue.
Preoperatively, detailed anatomic information regarding the anatomy of the portal circulation needs to be obtained through a CT scan with a portal venous phase, an MRI with contrast, or the venous phase of a superior mesenteric angiogram. If a selective shunt is being considered, ultrasound or mesenteric angiography should be done to confirm that there still is prograde flow to the liver. Surgery in any patient with portal hypertension is challenging. The surgeon and the anesthesiologist must be prepared for potential massive blood loss.
Mesocaval Interposition Shunt
The mesocaval shunt is considered the easiest and safest of the mesenteric decompressive operations, and therefore a good choice in the emergency setting (see Table 2). It avoids dissection in the porta hepatis, and therefore does not complicate later liver transplantation. It can be performed through a midline or subcostal incision. The superior mesenteric vein (SMV) is found by opening the root of the transverse mesocolon to the right of the superior mesenteric artery. The SMV is cleared and mobilized from the neck of the pancreas inferiorly, small braches ligated, while larger branches can be controlled with vessel loops. The infrarenal inferior vena cava (IVC) is identified by mobilizing the second and third portions of the duodenum. The IVC is cleared anteriorly and laterally to allow for placement of a side-biting clamp without tension. An anterior venotomy is made and a narrow ellipse of IVC is excised. An interposition graft of 12- to 18-mm ringed polytetrafluoroethylene (PTFE) is anastomosed first to the IVC and then to the anterior aspect of the SMV, using fine monofilament nonabsorable suture. In order to place the anastomosis anteriorly on the SMV, above its main branch points, the graft should assume a “C”-shaped configuration. From the IVC, the graft travels inferiorly in relation to the duodenum, then anteriorly across its third portion and the uncinate process of the pancreas. It is important to recognize that the IVC and the SMV are not parallel structures, and the end of the PTFE graft must be cut on a bias to accommodate this discrepancy. The SMV is often thin walled, and tearing this vein can be minimized by placing stay sutures at the toe and heal of the anastomosis; performing the right side of the anastomosis from inside the vessel, rostral to caudal, while the assistant coapts the SMV and the PTFE graft assuring that there is no tension; and then finally running the left or outside portion of the anastomosis. The surgeon should avoid the tendency to take large bites of the SMV wall as this will “flatten” the back wall of the SMV and diminish the patency of the anastomosis or even occlude the SMV. The length of the graft is particularly important—too long and it may bend on itself; too short and it may distort or kink the SMV. At the conclusion of the procedure, the effectiveness of the shunt in decompressing the portal circulation should be confirmed by obliquely inserting a 25-gauge needle attached to IV extension tubing into the PTFE graft and measuring the pressure gradient with and without a vascular clamp occluding the graft on the IVC side. If effective, the pressure in the shunt with the clamp off should be within several mm Hg of the patient’s central venous pressure.
TABLE 2. Key Technical Steps and Potential Pitfalls
Distal Splenorenal Shunt
Technically, the distal splenorenal shunt is a challenging operation and is most appropriate for elective surgery and not for a patient who is actively hemorrhaging (see Table 2). It disconnects the portal system from the esophageal venous plexus and drains the varices onto the renal vein. The operation is performed through a left subcostal incision. The lesser sac is entered through the gastrocolic ligament, and mobilizing the inferior border of the pancreas cephalad identifies the splenic vein. The splenic vein is fully mobilized from the confluence with the SMV for a distance of 6 to 7 cm. This requires the ligation and division of numerous small splenic vein branches to the pancreas as well as the inferior mesenteric vein (IMV). To minimize bleeding or inadvertent tearing of these fragile branches, which can then retract into the pancreas, ligating the pancreatic side with very fine sutures should be performed before tying the splenic vein side. Care should also be taken to divide the coronary vein and the right gastroepiploic vein, as these are important communications with the perioesophageal venous plexus. The left renal vein is then identified, inferiorly and somewhat deeper to the splenic vein. The left adrenal and gonadal veins are ligated and divided. The splenic vein is divided close to the portal confluence, and the portal side is oversewn. The splenic vein is then swung down to the left renal vein and a side-to-side running anastomosis is performed.
Special Intraoperative Considerations
Patients who have been fluid-resuscitated after sustaining a major hemorrhage may develop significant retroperitoneal edema that in the setting of thickened mesentery that often accompanies portal hypertension may make the identification of the SMV difficult. Use of an oblique incision in the retroperitoneum (as opposed to a longitudinal one) just lateral to the palpated SMA often solves this dilemma. If not, the surgeon should remember that when the duodenum is Kocherized and the connective tissue inferior to the third portion of the duodenum is dissected from the patient’s right to left, the first major vascular structure encountered is the SMV.
Preoperative imaging of the splanchnic venous system is occasionally misleading. An SMV that appeared to be an appropriate target for placement of a mesocaval shunt may, upon actual inspection, prove to be sclerosed or recanalized from previous thrombosis. Keeping in mind the primary goal of the operation, which is to decompress the varices that are the source of life-threatening bleeding, when such unsuspected anatomic variations are encountered, the surgeon must be prepared to choose an alternate procedure such as a central or distal splenorenal shunt or portocaval shunt.
Postoperative Management
Patients must be monitored for signs of hepatic decompensation, coagulopathy, and encephalopathy postoperatively if a mesocaval shunt has been performed. Rarely, the shunt may need to be revised or ligated if these complications occur. Doppler ultrasound is useful to demonstrate patency. A comprehensive guide to the care of patients with cirrhosis and hepatic dysfunction is complex and beyond the scope of this chapter.
Case Conclusion
The patient is subsequently readmitted three times with recurrent variceal hemorrhage. Mesenteric angiography demonstrates hepatopetal flow in the portal vein. A distal splenorenal shunt is performed. At 12 months postoperatively the patient has not had recurrent hemorrhage.
TAKE HOME POINTS
· Gastroesophageal varices are the likely source of acute upper GI bleeding in patients who have a known history of cirrhosis or who have clinical stigmata of chronic liver disease.
· Early endoscopy is the key to accurate diagnosis.
· Endoscopic banding is first-line treatment for bleeding esophageal varices.
· Octreotide is the preferred pharmacologic treatment for bleeding gastroesophageal varices.
· TIPSS is effective in decompressing the portal venous system but has limited durability and is often best used as a bridge to transplantation.
· For patients who require a surgical shunt and who may be candidates for a liver transplant in the future, the mesocaval “C” shunt is the preferred surgical procedure.
SUGGESTED READINGS
Cameron JL, Sandone C. Shunts in Atlas of Gastrointestinal Surgery second edition. Hamilton 2007 BC Decker.
Elwood DR, Pomposelli JJ, Pomfret EA, et al. Distal splenorenal shunt: preferred treatment for recurrent variceal hemorrhage in the patient with well compensated cirrhosis. Arch Surg 2006;141:385–388.
Garcia - Tsao G, Bosch J. Management of Varices and Variceal Hemorrhage in Cirrhosis. N Eng J Med 2010 362;9:823–832.
Knechtle SJ. Portal Hypertension: From Eck’s fistula to TIPS. Ann Surgery 2003;238:S49–55.