急性肝衰竭指南 AASLD 2011(英文）

AASLD POSITION PAPER Introduction to the Revised American Association for the Study of Liver Diseases Position Paper on Acute Liver Failure 2011 William M. Lee, R. Todd Stravitz, and Anne M. Larson The full text of the position paper is available at: www.aasld.org/ practiceguidelines/Documents/AcuteLiverFailureUpdate2011.pdf. Preamble The present version of the American Association for the Study of Liver Diseases (AASLD) Position Paper represents a thorough overhaul from the previous version of 2005. In addition to two new additional authors, the revision includes updated expert opinion regarding (1) etiologies and diagnosis, (2) therapies and intensive care management, and (3) prognosis and transplantation. Because acute liver failure (ALF) is an orphan disease, large clinical trials are impossible and much of its management is based on clinical experi- ence only. Nonetheless, there are certain issues that continue to recur in this setting as well as growing consensus (amidst innovation) regarding how to maximize the ALF patient’s chance of recovery. The changes in ALF management are not global in nature, but are more consistent with incremental experience and improvements in diagnosis and intensive care unit management. Introduction The diagnosis of ALF hinges on identifying that the patient has an acute insult and is encephalopathic. Imaging in recent years has suggested ‘‘cirrhosis,’’ but this is often an overcall by radiology, because a regener- ating massively necrotic liver will give the same nodular profile as cirrhosis.1 It is vital to promptly get viral hep- atitis serologies, including A-E as well as autoimmune serologies, because these often seem to be neglected at the initial presentation. Fulminant Wilson’s disease can be diagnosed most effectively not by waiting for copper levels (too slow to obtain) or by obtaining ceruloplas- min levels (low in half of all ALF patients, regardless of etiology), but by simply looking for the more readily available bilirubin level (very high) and alkaline phos- phatase (ALP; very low), such that the bilirubin/ALP ra- tio exceeds 2.0.2 The availability of an assay that meas- ures acetaminophen adducts has been used for several years as a research tool and has improved our clinical recognition of acetaminophen cases when the diagnosis is obscured by patient denial or encephalopathy.3 Any patient with very high aminotransferases and low biliru- bin on admission with ALF very likely has acetamino- phen overdose, with the one possible exception being those patients who enter with ischemic injury. Obtain- ing autoantibodies should be routine and a low thresh- old for biopsy in patients with indeterminate ALF should be standard, given that autoimmune hepatitis may be the largest category of indeterminate, after unrecognized acetaminophen poisoning.4 Advances in Management of ALF The medical management of ALF has not been extensively studied and remains poorly defined. In the absence of evidence-based clinical trials, experts from 23 centers in the United States have proposed detailed management guidelines by consensus.5 Since the last AASLD Position Paper, several noteworthy advances have been made in assessing the risk of developing, and managing, specific complications of ALF. All AASLD Practice Guidelines are updated annually. If you are viewing a Practice Guideline that is more than 12 months old, please visit www.aasld.org for an update in the material. Abbreviations: AASLD, the American Association for the Study of Liver Diseases; ALF, acute liver failure; ALP, alkaline phosphatase; CPP, cerebral perfusion pressure; ICH, intracranial hypertension; ICP, intracranial pressure; INR, international normalized ratio; MAP, mean arterial pressure; MELD, model for end-stage liver disease. From the University of Texas Southwestern Medical Center, Dallas, TX. Received December 2, 2011; accepted December 2, 2011. Address reprint requests to: William Lee, M.D., University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390. E-mail: william.lee@utsouthwestern.edu; fax: 214-648-8955. Copyright VC 2011 by the American Association for the Study of Liver Diseases. View this online at wileyonlinelibrary.com. DOI 10.1002/hep.25551 Potential conflicts of interest: Dr. Lee received grants from Gilead, Genentech, and Bristol-Myers Squibb. Dr. Larson received royalties from UpToDate. 965 A detailed analysis of serum ammonia in patients with ALF identified a concentration of 75 lM as an important threshold below which patients rarely de- velop intracranial hypertension (ICH).6 Conversely, ar- terial ammonia levels of >100 lM on admission rep- resent an independent risk factor for the development of high-grade hepatic encephalopathy, and a level of >200 lM predicts ICH. The risk of developing ICH is decreased by raising the serum sodium to 145-155 mEq/L with hypertonic saline.7 Once established, how- ever, the medical treatment of ICH must bridge patients to liver transplantation, because no treatment permanently reverses cerebral edema. In cases of ICH refractory to osmotic agents (e.g., mannitol and hyper- tonic saline), therapeutic hypothermia (cooling to a core temperature of 32�C-34�C) has been shown to bridge patients to transplantation,8 but is associated with a theoretical risk of impairing liver regeneration. To optimize neurological recovery after ALF, mean arterial pressure (MAP) and cerebral perfusion pressure (CPP) must be raised to avoid cerebral underperfusion and anoxia. In hypotensive patients with ALF, intravas- cular volume should be repleted first with normal sa- line, and vasopressors should be administered subse- quently to titrate the MAP to >75 mmHg and CPP to 60-80 mmHg. Vasopressin, or its analog, terlipres- sin, is often added to norepinephrine in critically ill patients who remain hypotensive on norepinephrine, but was reported to increase intracranial pressure (ICP) in patients with ALF.9 More recent data suggest, however, that vasopressin and analogs increase cerebral perfusion without increasing ICP and may be used safely as an adjunct to norepinephrine.10 It is generally accepted that patients with ALF have a bleeding diathesis based upon elevation of the inter- national normalized ratio (INR). Concern about the safety of inserting ICP monitors and other invasive devices has prompted the use of recombinant factor VIIa,11 although the practice has been associated with thrombotic complications in patients with ALF.12 However, a recent study has suggested that global hemostasis assessed by thromboelastography usually remains normal, suggesting that the perceived bleeding risk based upon INR may be overstated.13 Prognosis and Transplantation To date, it often remains difficult to predict which ALF patients will ultimately require transplantation. Newer models, including the model for end-stage liver disease (MELD) score, have not improved our accu- racy. In fact, the discriminative power of the MELD was not found to be superior to that of the INR or the King’s College Hospital criteria.14 In addition, equating transplantation with death, in many models, inflates the positive predictive value of a particular sys- tem. The King’s College Criteria remain the most clin- ically useful, with a sensitivity of 68%-69% and a specificity of 82%-92%.15 However, reliance entirely upon any set of guidelines cannot be recommended. Despite great early interest in liver support systems, the field has had little forward movement since our last publication. Both artificial (i.e., sorbent-based) and bio- artificial (i.e., cell-based) systems have been tested. There has been no good evidence that any artificial sup- port system reliably reduces mortality in the setting of ALF.16,17 Thus, the currently available liver support sys- tems cannot be recommended outside of clinical trials. Liver transplantation remains the only definitive treatment for patients who fail to demonstrate recovery. The 1-year survival after cadaveric liver transplant for ALF is less than that observed in patients transplanted for chronic liver failure.18 However, after the first year, this trend had reversed and ALF patients have a better long-term survival. The use of live donor liver trans- plantation and auxiliary liver transplant remain contro- versial.19 Urgent cadaveric liver transplantation remains the standard of care in the setting of ALF. Developing effective methods of liver support or other alternatives to transplantation and better prog- nostic scoring systems remain key goals to further improve overall survival rates and avoid unnecessary transplants. References 1. Poff JA, Coakley FV, Qayyum A, Yeh BM, Browne LW, Merriman RB, et al. Frequency and histopathologic basis of hepatic surface nodularity in patients with fulminant hepatic failure. Radiology 2008;249: 518-523. 2. Korman JD, Volenberg I, Balko J, Webster J, Schiodt FV, Squires RH, Jr., et al. Screening for Wilson disease in acute liver failure: a compari- son of currently available diagnostic tests. HEPATOLOGY 2008;48: 1167-1174. 3. Khandelwal N, James LP, Sanders C, Larson AM, Lee WM; and the Acute Liver Failure Study Group. Unrecognized acetaminophen toxicity as a cause of indeterminate acute liver failure. HEPATOLOGY 2011;53: 567-576. 4. Stravitz RT, Lefkowitch JH, Fontana RJ, Gershwin ME, Leung PSC, Sterling RK, et al. Autoimmune acute liver failure: proposed clinical and histological criteria. HEPATOLOGY 2011;53:517-526. 5. Stravitz RT, Kramer AH, Davern T, Shaikh AOS, Caldwell SH, Mehta RL, et al. Intensive care of patients with acute liver failure: recommen- dations of the Acute Liver Failure Study Group. Crit Care Med 2007; 35:2498-2508. 6. Bernal W, Hall C, Karvellas CJ, Auzinger G, Sizer E, Wendon J. Arte- rial ammonia and clinical risk factors for encephalopathy and intracra- nial hypertension in acute liver failure. HEPATOLOGY 2007;46: 1844-1852. 966 LEE, STRAVITZ, AND LARSON HEPATOLOGY, March 2012 7. Murphy N, Auzinger G, Bernal W, Wendon J. The effect of hypertonic sodium chloride on intracranial pressure in patients with acute liver failure. HEPATOLOGY 2002;39:464-470. 8. Jalan R, Olde Damink SW, Deutz NE, Hayes PC, Lee A. Moderate hypothermia in patients with acute liver failure and uncontrolled intra- cranial hypertension. Gastroenterology 2004;127:1338-1346. 9. Shawcross DL, Davies NA, Mookerjee RP, Hayes PC, Williams R, Lee A, et al. Worsening of cerebral hyperemia by the administration of ter- lipressin in acute liver failure with severe encephalopathy. HEPATOLOGY 2004;39:471-475. 10. Eefsen M, Dethloff T, Frederiksen HJ, Hauerberg J, Hansen BA, Larsen FS. Comparison of terlipressin and noradrenalin on cerebral perfusion, intracranial pressure, and cerebral extracellular concentrations of lactate and pyruvate in patients with acute liver failure in need of inotropic support. J Hepatol 2007;47:381-386. 11. Shami VM, Caldwell SH, Hespenheide EE, Arseneau KO, Bickston SJ, Macik BG. Recombinant activated factor VII for coagulopathy in ful- minant hepatic failure compared with conventional therapy. Liver Transpl 2003;9:138-143. 12. Pavese P, Bonadona A, Beaubien J, Labrecque P, Pernod G, Letoublon C, Barnoud D. FVIIa corrects the coagulopathy of fulminant hepatic failure but may be associated with thrombosis: a report of four cases. Can J Anesth 2005;52:26-29. 13. Stravitz RT, Lisman T, Luketic VA, Sterling RK, Puri P, Fuchs M, et al. Minimal effects of acute liver injury/acute liver failure on hemostasis as assessed by thromboelastography. J Hepatol 2011;56: 129-136. 14. Schmidt LE, Larsen FS. MELD score as a predictor of liver failure and death in patients with acetaminophen-induced liver injury. HEPATOLOGY 2007;45:789-796. 15. McPhail MJ, Wendon JA, Bernal W. Meta-analysis of performance of King’s College Hospital Criteria in prediction of outcome in nonparacetamol-induced acute liver failure. J Hepatol 2010;53: 492-499. 16. McKenzie TJ, Lillegard JB, Nyberg SL. Artificial and bioartificial liver support. Semin Liver Dis 2008;28:210-217. 17. Kjaergard LL, Liu J, Als-Nielsen B, Gluud C. Artificial and bioartificial support systems for acute and acute-on-chronic liver failure: a system- atic review. JAMA 2003;289:217-222. 18. Freeman RB, Jr., Steffick DE, Guidinger MK, Farmer DG, Berg CL, Merion RM. Liver and intestine transplantation in the United States, 1997-2006. Am J Transplant 2008;8:958-976. 19. Campsen J, Blei AT, Emond JC, Everhart JE, Freise CE, Lok AS, et al. Outcomes of living donor liver transplantation for acute liver failure: the adult-to-adult living donor liver transplantation cohort study. Liver Transpl 2008;14:1273-1280. HEPATOLOGY, Vol. 55, No. 3, 2012 LEE, STRAVITZ, AND LARSON 967 AASLD Position Paper Corrections to the AASLD Position Paper: The Management of Acute Liver Failure: Update 2011 William M. Lee, MD,1 Anne M. Larson, MD,2 and R. Todd Stravitz, MD3 * Corresponding author: William M. Lee From the 1University of Texas, Southwestern Medical Center at Dallas, 5959 Harry Hines Boulevard, HP4.420E, Dallas, TX 75390-8887;2Director, Swedish Liver Center, Swedish Health Systems, 1101 Madison Street #200, Seattle WA 98104-1321; 3Virginia Commonwealth University, Section of Hepatology, PO Box 980341, 1200 East Broad Street, Richmond, VA 23298 The electronic version of this article can be found online at: http://www.aasld.org/practiceguidelines/Documents/AcuteLiverFailureUpdate2011.pdf Published November 5, 2011 at www.aasld.org Copyright © 2011 by the American Association for the Study of Liver Diseases Correction December 2, 2011 Upon publication of the AASLD Position Paper on the Management of Acute Liver Failure: Update 2011, we noticed that the end of paragraph three on page 14 was omitted. The complete paragraph can be found below.     In patients who do not respond to a volume challenge and norepinephrine, vasopressin and its analogues may potentiate the effects of norepinephrine and allow a decrease in its infusion rate, which in turn may avoid intense vasoconstriction in peripheral tissues which can lead to ischemia. However, the use of vasopressin/terlipressin was discouraged by a study reporting cerebral vasodilation and increased ICH in severely encephalopathic patients.1 A more recent study, however, has shown that terlipressin increased CPP and cerebral perfusion without increasing ICP, and concluded that vasopressin and analogues might be useful with norepinephrine to ensure adequate brain perfusion.2 In the US where terlipressin is not yet available, the addition of vasopressin should be considered in hypotensive patients requiring escalating doses of norepinephrine, but should be administered with caution in patients with ICH. Finally, persistence of hypotension despite volume repletion and vasopressors should prompt a trial of hydrocortisone.3, 4 References 1. Shawcross DL, Davies NA, Mookerjee RP, Hayes PC, Williams R, Lee A, et al. Worsening of cerebral hyperemia by the administration of terlipressin in acute liver failure with severe encephalopathy. Hepatology 2004;39:471-475. 2. Eefsen M, Dethloff T, Frederiksen HJ, Hauerberg J, Hansen BA, Larsen FS. Comparison of terlipressin and noradrenalin on cerebral perfusion, intracranial pressure and cerebral extracellular concentrations of lactate and pyruvate in patients with acute liver failure in need of inotropic support. J Hepatol 2007;47:381-6. 3. Harry R, Auzinger G, Wendon J. The effects of supraphysiological doses of corticosteroids in hypotensive liver failure. Liver Internat 2003;23:71-7. 4. Harry R, Auzinger G, Wendon J. The clinical importance of adrenal insufficiency in acute hepatic dysfunction. Hepatology 2002;36:395-402. POSITION PAPER AASLD Position Paper: The Management of Acute Liver Failure: Update 2011 William M. Lee, MD,1 Anne M. Larson, MD,2 and R. Todd Stravitz, MD3 Preamble These recommendations provide a data-supported approach. They are based on the following: 1) Formal review and analysis of recently-published world litera- ture on the topic [Medline search]; 2) American Col- lege of Physicians Manual for Assessing Health Prac- tices and Designing Practice Guidelines;1 3) guideline policies, including the AASLD Policy on the Develop- ment and Use of Practice Guidelines and the AGA Policy Statement on Guidelines;2; and 4) the experi- ence of the authors in the specified topic. Intended for use by physicians, the recommenda- tions in this document suggest preferred approaches to the diagnostic, therapeutic and preventive aspects of care. They are intended to be flexible, in contrast to standards of care, which are inflexible policies to be followed in every case. Specific recommendations are based on relevant published information. This docu- ment has been designated as a Position Paper, since the topic contains more data based on expert opinion than on randomized controlled trials and is thus not considered to have the emphasis and certainty of a Practice Guideline. Nevertheless, it serves an important purpose of facilitating proper and high level patient care and we have characterized the quality of evidence supporting each recommendation, in accordance with the Practice Guidelines Committee of the AASLD recommendations used for full Practice Guidelines (Table 1)3 These recommendations are fully endorsed by the AASLD. Introduction Acute liver failure (ALF) is a rare condition in which rapid deterioration of liver function results in altered mentation and coagulopathy in individuals without known pre-existing liver disease. U.S. esti- mates are placed at approximately 2,000 cases per year.4,5 A recent estimate from the United Kingdom was 1-8 per million population.6 The most promi- nent causes include drug-induced liver injury, viral hepatitis, autoimmune liver disease and shock or hy- poperfusion; many cases (�15%) have no discernible cause.7 Acute liver failure often affects young persons and carries a high morbidity and mortality. Prior to transplantation, most series suggested less than 15% survival. Currently, overall short-term survival (one year) including those undergoing transplantation is greater than 65%.7 Because of its rarity, ALF has been difficult to study in depth and very few con- trolled therapy trials have been performed. As a result, standards of intensive care for this condition have not been established although a recent guideline provides some general directions.8 Definition The most widely accepted definition of ALF includes evidence of coagulation abnormality, usually an International Normalized Ratio (INR) �1.5, and any degree of mental alteration (encephalopathy) in a patient without preexisting cirrhosis and with an illness of <26 weeks’ duration.9 Patients with Wilson disease, vertically-acquired hepatitis B virus (HBV), or autoim- mune hepatitis may be included in spite of the possi- bility of cirrhosis if their disease has only been recog- nized for <26 weeks. A number of other terms have Abbreviations: ALF, acute liver failure; NAC, N-acetylcysteine; HELLP, Hemolysis, Elevated Liver Enzymes, Low Platelets syndrome; gm/day, grams per day; gm/kg, grams per kilogram; ICH, intracranial hypertension; ICP, intracranial pressure; INR, international normalized ratio; CT, computerized tomography; US ALFSG, United States Acute Liver Failure Study Group; CPP, cerebral perfusion pressure; MAP, mean arterial pressure; mg/dL, milligrams per deciliter, SIRS, systemic inflammatory response syndrome; FFP, fresh frozen plasma; rFVIIa, recombinant activated factor; GI, gastrointestinal; H2, histamine-2; PPI, proton pump inhibitors; CVVHD, continuous venovenous hemodialysis; AFP, alpha fetoprotein; MELD, Model for End-stage Liver Disease; mg/kg, milligrams per kilogram; IU/L, international units per liter; From the 1University of Texas, Southwestern Medical Cente