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Fulminant Liver Failure Stevo’s AHD April 3rd, 2008 Introduction Sue, a 28 year old previously healthy 80 kg woman, is brought to the emerg department with progressive obtundation. Her ALT is 7,200 U/L, AST is 11,300 U/L, INR is 3.6 and a total bilirubin of 5.3 mg/dL. As the ICU fellow on, you are consulted to figure out what is going on and how to manage her. Take it away Dave…. 1. 2. 3. 4. 5. 6. 7. What are some of the overarching themes of managing ALF? How is acute liver failure defined? How is fulminant liver failure defined? What is the differential for the etiologies of ALF? How would you differentiate between these etiologies? What is the most common cause of ALF in North America and what it is pathophysiology? What is the most common cause in the developing world? Why? What are the specific therapies for each of these identified etiologies of ALF? Please give names, doses and frequency. Describe the grades of hepatic encephalopathy. What is her grade? Presumed agents of idiosyncratic drug induced hepatic failure Alcoholic hepatitis ----Pentoxifylline (400 mg PO TID), looked at in one single centre randomized study and showed a benefit where short-term survival was significantly better with active therapy (25 versus 46 percent, respectively). Norfloxacin in FHF A randomized trial reported significant benefits with the oral administration of norfloxacin at 400 mg/day to 68 patients with; cirrhosis with ascites with a total serum protein <1.5 g/L And impaired renal function (serum creatinine >106 micromol/L & BUN >25 mg/dL, serum sodium <130 meq/L) Or severe liver disease (Child-Pugh score >9 points with serum bilirubin >3 mg/dL). Benefits include a significantly decreased one-year probability of SBP (7 versus 61 percent) and hepatorenal syndrome (28 versus 41 percent), and improved survival at three months (94 versus 62 percent) and one year (60 percent versus 48 percent, p = 0.05). Grades of hepatic encephalopathy Now onto NNNNNNaisan 8. Can we prognosticate at all for Sue right now (ie lactate values vs other values)? What is her MELD score? What is the MELD score anyway? What is the Child-Pugh score? MELD score It is calculated according to the following formula: 3.8 x log (e) (bilirubin mg/dL) + 11.2 x log (e) (INR) + 9.6 log (e) (creatinine mg/dL) MELD score interpretation In interpeting the MELD Score in hospitalized patients, the 3 month mortality is: 40 or more - 100% mortality 30-39 - 83% mortality 20-29 - 76% mortality 10-19 - 27% mortality <10 - 4% mortality Child-Turcotte-Pugh score Gordo and interventions for FHF 9. What interventions would you like to start now? Specifically discuss the rationale and evidence for the following; Lactulose Oral non-absorbable antibiotics Prophylactic systemic antibiotics Agents of sedation and analgesia Correction of coalopathy (FFP, Vitamin K, Platelets, cryoprecipitate, aminocaproic acid, factor VIIIa). Routine vs procedure specific Routine albumin administration Gastric acid suppression Nutrition Glycemic control Onto Yoan and infections and ascites 10. What is her risk for infection? How about from fungal pathogens? She has significant ascites. With a large right sided pleural effusion that is making it moderately difficult to ventilate her. 11. How do you manage her ascites? 12. What indicates SBP? How is it managed? Hepatic encephalopthy and crazy Yoan Her CNS status continues to deteriorate and now she is unresponsive to pain. 13. What etiologies should you consider at this point? What investigations/history do you want to get specifically? 14. What is the pathophysiology of cerebral edema in ALF? What’s the pathophysiology of multiple organ failure in ALF? 15. What is the evidence for ICP monitoring? What can be done in cases of high ICP? Take it away Scotto… Things are not going so well for Sue. A GI keener says that we should just give up and send her to MARS. 16. What is MARS? Is there any evidence for it? How does it work? 17. What other similar technologies are out there for ALF? Evidence for MARS; •Initial Phase I trials •Subsequent randomized trial in acute on chronic hepatic failure, which was stopped early •MARS registry paper and effects in encephalopathy •Meta-analysis of 4 randomized and 2 non-randomized trials •Evidence in hepato-renal syndrome Scot redux She is now going into progressive renal failure. 18. What is the pathophysiology of hepato-renal syndrome? 19. How can you differentiate hepato-renal syndrome from other causes of renal failure commonly found in the ICU? What are the diagnostic criteria for hepatorenal failure? 20. What treatment options are there for hepatorenal syndrome? What are the prognostic implications of hepato-renal syndrome? Pathophysiology of HRS splanchnic vasodilation, possibly due to nitric oxide (pathogenesis of ascites), leads to reduced GFR, reduced Na+ excretion. increase in the ratio of vasoconstrictor thromboxanes to vasodilator prostaglandins may lead to renal ischemia. Other potential, although unproven, mediating factors in the renal vasoconstriction include endotoxemia (due, at least in part, to lack of hepatic removal), endothelin, the release of false neurotransmitters, and increased renal sympathetic tone (induced in part by an hepatorenal reflex that is activated by elevated hepatic sinusoidal pressure) Diagnostic criteria for HRS 1. 2. 3. 4. 5. Chronic or acute hepatic disease with advanced hepatic failure and portal hypertension A plasma creatinine concentration above 133 µmol/L that progresses over days to weeks. As noted above, the rise in plasma creatinine with reductions in glomerular filtration rate may be minimized by the marked reduction in creatinine production. The absence of any other apparent cause for the renal disease, including shock, ongoing bacterial infection, current or recent treatment with nephrotoxic drugs, and the absence of ultrasonographic evidence of obstruction or parenchymal renal disease. It is particularly important to exclude spontaneous bacterial peritonitis, which is complicated by acute renal failure that may be reversible in 30 to 40 percent of patients. Urine red cell excretion of less than 50 cells per high power field (when no urinary catheter is in place) and protein excretion less than 500 mg/day. Lack of improvement in renal function after volume expansion with intravenous albumin (1 g/kg of body weight per day up to 100 g/day) for at least two days and withdrawal of diuretics. Treatment: Prevention: SBP – dose of IV albumin (1.5 g/kg) at time of diagnosis, and another dose on third day of abx may reduce mortality. Alcoholic hepatitis – pentoxifylline may improve survival. Severe liver disease with cirrhosis and impaired renal function – norfloxacin. Active treatment: Correct underlying hepatic disease – eg. abstinence from EtOH in cirrhosis, or tx with lamivudine in Hep B. Liver transplant Midodrine and octreotide titrated to increase MAP by 15 mmHg – reduces endogenous vasodilator release, and causes systemic vasoconstriction. Multiple studies show survival benefit. IV albumin at approximately 50 g/day for three or more days. Pentoxifylline is a tri-substituted xanthine unlike theophylline, is a hemorrheologic agent, i.e. an agent that affects blood viscosity. It’s used commonly for claudication sympotoms. In one four-week study, 101 patients with severe alcoholic hepatitis were randomly assigned to pentoxifylline (400 mg orally three times daily) or placebo. Short-term survival was significantly better with active therapy (25 versus 46 percent, respectively). Naisans baaack.. You successfully initiate CVVHD. Your annoying GI keener suggests talking to the transplant team? 21. What are the indications for liver transplant in ALF? What are the contra-indications? Transplant criteria The critical criteria include; a) age >18 yrs b) a life expectancy without a liver transplant of <7 days c) onset of hepatic encephalopathy within 8 wks of the first symptoms of liver disease d) the absence of preexisting liver disease e) residence in an intensive care unit f) at least one of the following: Ventilator dependence, Requiring renal replacement therapy, An INR >2.0. Transplant contra-indications Active drug or alcohol abuse, Active suicidal ideation, or history of a previous suicide attempt Specific exclusion criteria for liver transplantation have not been formally established, although it is generally agreed that active sepsis and extrahepatic malignancy are absolute contraindications. Still controversial are conditions such as HIV infection in the absence of acquired immunodeficiency syndrome, large-size hepatocellular cancer (>5 cm), or cholangiocarcinoma Liver transplant (con’t) Sue goes onto transplantation and successfully undergoes orthotropic liver transplantation. 22. What are the complications that you can expect in the post op liver transplant patient? 23. What are some of the overarching themes of management of the fresh posttransplant liver? 24. Is there any evidence for using albumin as the resuscitation fluid post liver transplant? Post op liver transplant complications Primary Nonfunction Intra-abdominal Bleeding Vascular Thrombosis Biliary Leak Infections Acute Rejection