الفهرس 
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Abstract
SUMMARY
Surgery in a patient with liver disease, especially end-stage liver disease with cirrhosis and portal hypertension, poses a formidable challenge for all physicians involved. Targeted interventions before surgery may help to prevent complications and improve outcomes.
The cornerstones of perioperative management are medical treatment of the complications of liver disease, including coagulopathy, ascites, encephalopathy, and malnutrition. Attention must also be paid to risk factors for infection and renal dysfunction after surgery. Sepsis, coagulopathy, and emergency surgery are most strongly correlated with postoperative mortality. (Rizvon MK, et al 2003)
Evolving knowledge of the effects of anesthesia, improving surgical techniques, and use of improved diagnostic tests will help reduce perioperative complications. Established risk stratification systems such as the CTP score, the MELD score, and the ASA physical status class should also be used when evaluating a patient with liver disease for potential surgery. Therefore, a multidisciplinary approach to postoperative care is imperative and should include input from anesthesiologists, surgeons, internists, and hepatologists. (Rizvon MK, et al 2003)
Acute liver failure, is a rare liver disorder that often leads to devastating consequences. It is one of the most challenging gastrointestinal emergencies encountered in clinical practice and encompasses a pattern of clinical symptoms and pathophysiological responses associated with the rapid arrest of normal hepatic function. The syndrome is defined by the sudden onset of hepatic encephalopathy in an otherwise healthy individual, often in association with coagulopathy, jaundice and multisystem organ failure. Until recently, FHF carried a very high mortality rate (widely reported to be in excess of 80%)1; however, with an improved understanding and recognition of the syndrome, more aggressive medical therapy, intensive care monitoring. and the advent of orthotopic liver transplantation (OLT) as a treatment option, survival rates have improved considerably.( (Sass and Shakil et al 2005)
Although resulting from a primary liver insult, is essentially a multiorgan disease with a myriad of systemic complications. It usually begins as jaundice with. a rapid onset of encephalopathy. Early recognition of the disease and an expeditious transfer to a transplantation center is critical as a multidisciplinary approach and intense monitoring is required if a successful outcome is to be achieved. The mortality of patients with advanced FHF is high and the availability of liver transplantation has provided a means to rescue such patients. Survival prediction models, whether mathematic, serologic, or physiologic, have garnered much of the recent attention in the FHF literature. These prognostication tools are being designed to facilitate rapid clinical decision- making, which would allow transplant surgeons and hepatologists to make best use of the scarcely available.donor livers. Patients with ALF who fail to recover spontaneously require liver transplantation. Once selected for liver transplantation, the focus is on maintaining extrahepatic organ function, especially brain integrity, and to prevent and treat infection. After transplantation, a smooth transition of care between the operating room and ICU requires close communication between the anesthesiologist and intensivist. With well coordinated, meticulous care, patients with ALF can experience posttransplant survival rates comparable with those of patients with endstage liver disease. (Randolph H. et al 2010).
In surgical patients with underlying chronic liver disease, surgical outcomes correlate with hepatocellular function. The risk of surgery in such patients should be assessed preoperatively using Child-Pugh or Model for End Stage Liver Disease (MELD) severity scoring system. Patients with severe liver disease (eg, Child-Pugh C ) should not undergo any elective surgery and should be evaluated for liver transplantation. In patients who can proceed with surgery, coagulopathy should be corrected preoperatively and careful fluid management is required intraoperatively to avoid hypotention. Renal insufficiency (as evidence by elevated creatinine) may indicate that hepatorenal syndrome has developed and carries a poor prognosis. (Paul Martin et al., 2009).
Anesthesiologists are keenly aware of the hepatic effects of anesthesia and that they must carefully choose anesthetics for patients with liver disease. There are a number of at least theoretical concerns about using particular anesthetics: Inhaled anesthetics, such as isoflurane, cause systemic vasodilation and depress cardiac output. These effects are of concern since many patients with advanced liver disease already have a hyperdynamic circulation because of peripheral vasodilation. Spinal or epidural anesthetics may reduce mean arterial pressure, which is of concern for similar reasons. Nitrous oxide has less of a depressive effect unless the patient has concomitant hypercapnia.
Another consideration is the hepatic metabolism of anesthetic agents. Use of halothane, which is 20% metabolized by the liver, is now uncommon, particularly if there is any concern about liver disease. In contrast, enflurane is only 4% metabolized by the liver. Numerous other anesthetics—including isoflurane, desflurane, and sevoflurane—have only minimal hepatic metabolism (< 0.2%), which makes them, along with nitrous oxide, the best anesthetic choices for patients with liver disease. (Paul Martin et al., 2009).
The more important issue in the consultation for our patient is the degree of operative risk associated with his underlying liver disease. A number of factors are pertinent, including the etiology and severity of the liver disease and the type of surgery planned. Literature dating back 40 years has associated acute viral and alcoholic hepatitis with poor outcomes in surgical patients. Major elective surgery for a patient with suspected acute hepatitis A, for example, should be deferred until the patient has recovered, barring some compelling reason for greater urgency, such as a perforated viscus. For patients with chronic liver disease, outcomes correlate with underlying hepatocellular function. chronic liver disease tends to run a predictable course. Patients with well-compensated cirrhosis may enjoy good health for many years. But once an index complication—such as variceal hemorrhage, ascites, hepatic encephalopathy, or jaundice—develops, prognosis rapidly worsens. (Ginés P et al., 1987)
When a patient with liver disease is evaluated for surgery, evidence should be sought to determine whether an index complication has already occurred. It is also important to determine whether portal hypertension is present. For a patient with liver disease, otherwise unexplained thrombocytopenia is a useful indicator of portal hypertension. (Poggio JL et al., 2000).
The study by Ziser 1999 also underscored the cumulative effect of risk factors, as the probability of developing a perioperative complication increased dramatically with the number of risk factors.
In conclusion, surgical recipients have considerable medical, physiological, and pharmacological problems; therefore, a clear understanding of the physiology of the disease process, the pharmacology of the immunosuppressive drugs, and the underlying surgical conditions is essential for these patients to safely undergo anesthesia and surgery. Local, regional, or general anesthesia can be safely delivered and a successful anesthetic and perioperative management can be provided. A registry for the perioperative problems of previously patients requiring other elective or emergency surgery is needed to formulate appropriate management and follow-up guidelines. (Kostopanagiotou et al., 1999).