From Alice Springs ICU 2009 Chronic liver disease: The clinical signs of decompensation include jaundice, ascites and encephalopathy. These are often precipitated by insults such as gastrointestinal bleeding, sepsis, dehydration, alcohol binge, new or reactivation of viral hepatitis. The patient requires supportive care of the liver dysfunction until the cause of acute deterioration is reversed. Management of the complications of liver failure: Ascites is almost invariable in patients with advanced chronic liver disease. The pathogenesis is a combination of portal hypertension, hypoalbuminaemia, excessive hepatic lymph formation and abnormalities in sodium and water balance. If patient is hypotensive with low albumin consider fluid resuscitation with albumin based solutions rather crystalloid solutions. If the patient has raised intrabdominal pressures consider paracentesis. Usually remove 3-5 litres of ascites and cover with albumin. Use 20% Albumin 100mls/2l ascites (if patient is hypovolaemic use 500mls 4% Albumin instead.) In patients who are not haemodynamically compromised control of ascites with salt and water restriction and use of diuretics is appropriate. Complications of diuretic Rx include -hypoNa (definitely stop when <120), -hypo or hyper -kalaemia -renal impairment (usually reversible), -hepatic encephalopathy, and -muscle cramps (can try quinine). Bleeding from the gastrointestinal tract due to oesophageal varices or gastric mucosal erosions. If active bleeding correct coagulopathy often have low platelets, low factors 2, 7, 9 and 10 and low fibrinogen levels. All patients should be place on omeprazole. Consider the use of octreotide to reduce portal pressures. Endoscopy should be done early if persistent bleeding despite pharmacological control. Encephalopathy is very rarely associated with raised intra cranial pressure in chronic liver disease. Prevent with the use of lactulose usual dose is 30 mls QID. Avoid sedative drugs particularly the benzodiazepines. Diazepam or lorazepam has to be used for alcohol withdrawal. Intubate and ventilate the patient if requires airway protection. Nutrition: These patients are often under nourished so feeds should be established early. Avoid high protein load as this may precipitate encephalopathy. Hepatamine may be added to feeds. This has little efficacy. Hypoglycaemia is common and results from impaired gluconeogensis, reduced glycogen stores and increased circulating insulin concentrations. Monitor BSL every 4 hours, and hourly if rapid changes, hypoglycemia or change in mental state. Support with dextrose solutions if low. Sepsis is the common cause of decompensation so consider the risk of spontaneous bacterial peritonitis and fungal infections. Subacute bacterial peritonitis Diagnosed by a ascitic polymorphonuclear count of >250/mm3 Albumin rehydration prevents renal failure and improves survival Albumin given at 1.5g/kg within 6 hours of diagnosis of SBP followed by 1g/kg on day 3 day reduces incidence of hepatorenal syndrome and mortality (one limited study) Consider prophylactic third generation cephalosporin. If becomes septic once on antibiotics or sick for more than one week consider fluconazole for candida infection. Renal failure is usually due to hypo perfusion or hepatorenal syndrome. Hepatorenal syndrome is either type 1 with acute deterioration or type 2 with rising serum creatinine over weeks or months. The criteria for diagnosis of hepatorenal syndrome are: 1)Chronic or acute liver disease with advanced hepatic failure and portal hypertension. 2)Low GFR defined by serum creatinine>130mmol/l or creatinine clearance <40ml/min 3)Absence of shock, bacterial infection and recent treatment with nephrotoxic drugs 4)No sustained improvement of renal function after volume expansion of 1.5l Normal Saline (this may be inappropriate if cerebral oedema is likely) 5)Proteinuria<0.5g/day, and no ultrasonographic evidence of renal tract disease. Additional criteria: a)Urine volume < 500ml/day b)Urine sodium <10mmol/l c)Urine osmolality >plasma osmolality d)Serum sodium < 130mmol/l The additional factors are what normally occurs but not required for diagnosis. Treatment of hepatorenal syndrome is with Terlipressin 0.5-2mg q4h i.v.(appendix 2) and albumin 1g/kg the first day then 20-40g/kg thereafter. Hepatorenal syndrome carries a poor prognosis and reversibility of the acute precipitant must be considered. Cardiovascular disturbances are common typically they have a low systemic vascular resistance and a high cardiac index. Respiratory problems include hyperventilation, ARDS and those associated with poor conscious state (atelectasis and aspiration.) Alcohol withdrawal: Patients with a heavy alcohol history must have thiamine 100mg daily and an alcohol withdrawal scale written up. Portal Hypertension Explanation: Portal hypertension is the main consequence of cirrhosis of the liver, and is responsible for its most common complications, the development of which mark the transition from compensated to decompensated liver disease. The most common complication is the development of ascites. The 2nd most common is hepatic encephalopathy. The 3rd most common is variceal bleeding, however variceal bleeding is the major cause of death in patients with chronic liver disease. Preventable complications include variceal bleeding, Spontaneous Bacterial Peritonitis (SBP), and Hepatorenal Syndrome (HRS). The severity of cirrhosis correlates strongly with overall patient survival. Child-Pugh classification of severity of liver disease (3) Variable Score 1 Score 2 Score 3 Ascites Absent Mild Mod/severe Encephalopathy Absent Stage I/II Stage III/IV Albumin (g/L) >35 28-35 <28 Br (mcmol/L) <34 34-51 >51 INR <1.7 1.7-2.3 >2.3 Child-Pugh A: 5-6 points, B: 7-9 points, C:10-15 points PATHOPHYSIOLOGY The portal v: is formed by the union of the superior mesenteric and splenic veins. It drains blood from the abdominal GIT, spleen, and pancreatic bed. A key consequence of increased portal pressure is the development of portosystemic collateral circulation that allows blood from the hypertensive portal system to return to the systemic circulation. These are varices. Portal pressure initially increases as a result of increased intrahepatic resistance, but once collaterals have formed, high portal pressure is maintained by an increased splanchnic blood inflow secondary to vasodilation from locally produced factors such as nitric oxide. In advanced cirrhosis, this vasodilation is so pronounced, that effective arterial blood volume decreases markedly, and arterial BP falls. As a consequence, arterial BP is maintained by by homeostatic activation of vasoconstrictive and natriuretic factors, resulting in Na and fluid retention. The combination of portal hypertension and splanchnic vasodilation alters intestinal capillary pressure and permeability, facilitating the accumulation of ascites. As the disease progresses, there is marked impairment of renal excretion of free water and renal vasoconstriction, which leads to dilutional hypoNa and the hepatorenal syndrome. Although it is the increased portal pressures that initially cause the formation of varices, it is the increased flow through them from hyperdynamic splanchnic circulation that causes their enlargement and then rupture. Normal pressures in the human portal venous system range from 3-6 mmHg. Portal hypertension is defined by an increase to >10 -12 mm Hg. Appendix 1 Liver Failure and Drug Doses Drugs requiring dosage alteration and/or monitoring in severe hepatic dysfunction: ACE Inhibitors Acitretin Allopurinol Aminophylline Amlodipine Amprenavir Amsacrine Antidepressants, SSRIs Azathioprine Azithromycin Benzodiazepines Bicalutamide Bisoprolol Bupivacaine Bupropion Cabergoline Carbamazepine Caspofungin Chloramphenicol Clindamycin Cyclophosphamide Cyclosporin Cytarabine Dacarbazine Danaparoid Daunorubicin Demeclocycline Didanosine Diltiazem Disopyramide Doxorubicin Efavirenz Epirubicin Erythromycin Felodipine Flecainide Fluorouracil Fusidic acid Gemcitabine Heparin Histamine H2 antagonists Hydralazine Idarubicin Indinavir Isotretinoin Itraconazole Lamotrigine Levetiracetam Lignocaine LMW Heparins Mercaptopurine Methoxsalen Metoclopramide Metoprolol Metronidazole Mexiletine Mirtazapine Mivacurium Moclobemide Modafinil Nelfinavir Nifedipine Nimodipine Olanzapine Ondansetron Opioid analgesics Paracetamol Phenobarbitone Phenytoin Procainamide Propylthiouracil Proton pump inhibitors Praziquantel Prazosin Propranolol Quetiapine Quinidine Reboxetine Repaglinide Rifabutin Rifampicin Risperidone Rocuronium Ropivacaine Roxithromycin Saquinavir Sirolimus Sodium nitroprusside Sulfamethoxazole Sulfonyurea hypoglycaemics Tacrolimus Tadalafil TetracyclineTheophyline Thiopentone Tramadol Tretinoin Verapamil Venlafaxine Vinca alkaloids Voriconazole Zidovudine Zoledronic acid Zolmitriptan Zolpidem Zopiclone Drugs that should be avoided in severe hepatic dysfunction: Abacavir Abciximab Acamprosate Amifostine Anastrozole Androgens Angiotensin II receptor antagonists Antidepressants, irreversible MAOIs Antidepressants, tricyclic Antihistamines (sedating) Antipsychotics (typical) Auranofin Bosentan Buspirone Capecitabine Carvedilol Cetrorelix Chlorpromazine Clomifene Clopidogrel Clozapine Cotrimoxazole COX-2 inhibitors Dantrolene Docetaxel Drotrecogin alfa (activated) Entacapone Ergot alkaloids Etoposide Ezetimibe Fenofibrate Flutamide Gallantamine Ganirelix Gemfibrozil Gestrinone Griseofulvin Ifosfamide Interferons Irinotecan Iron (parenteral) Isoniazid Ketoconazole Labetalol Lercanidipine Methotrexate Methyldopa Mianserin Mitoxantrone Nandrolone Nevirapine Nilutamide NSAIDS Oestrogens Leflunomide Lopinavir Mefloquine Methysergide Moxifloxacin Naratriptan Paclitaxel Pioglitazone Procarbazine Progestogens Pyrazinamide Quinupristin/dalfopristin Raloxifene Raltitrexed Riluzole Ritonavir Rivastigmine Rosiglitazone Sibutramine Sildenafil Sodium aurothiomalate Statins Sumatriptan Tamsulosin Terbinafine Tiagabine Tibolone Tirofiban Topotecan Toremifene Valproic acid Vardenafil Verteporfin Warfarin Zafirlukast Zalcitabine References: Sanford Guide to Antimicrobial Therapy 2002; Drug Data Handbook, 3rd Edn, 1998 BNF Edn 46, Sept 2003 MIMS Prepared by: Vanessa Simpson, Drug Information Pharmacist Date: 3rd revision, January 2004 Appendix 2 DRUG NAME TERLIPRESSIN ACETATE (GLYPRESSIN) ACTION Vasoconstriction Reduction of portal venous pressure INDICATIONS For the treatment of acute oesophageal variceal haemorrhage For the treatment of hepatorenal syndrome PREPARATION & ADMINISTRATION 1mg vial with 5ml diluent Reconstitute by introducing the sterile diluents into the vial Reconstituted solution should be used immediately Given as a bolus injection ROUTE Strict intravenous to avoid local tissue necrosis. Central venous administration is preferred. PRECAUTIONS Patients with hypertension and heart disease Contraindicated in pregnancy COMPATIBILITIES n/a DOSAGE For the treatment of acute esophageal vertical hemorrhage: 1-2mg q4h iv For the treatment of hepatorenal syndrome: 2-12 mg/day iv in 2-6 divided doses. Often administered concurrently with albumin. ADVERSE REACTIONS Hypertension Abdominal pain, nausea & diarrhoea Headache Bradycardia Local necrosis Hyponatraemia due to antidiuretic effect OBSERVATIONS Heart Rate Blood Pressure Fluid Balance REFERENCES Product Information 2004 Ioannou G, Doust J, Rockey DC. Terlipressin for acute esophageal variceal hemorrhage (Cochrane Review). In: The Cochrane Library, Issue 2, 2004. Chichester, UK: John Wiley & Sons, Ltd. Solanki P et al. J Gastroenterol Hepatol 2003; 18(2): 152-6. |
