acute hepatic failure
TRANSCRIPT
![Page 1: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/1.jpg)
Acute hepatic failure
PB Sherren ST7 ICM
![Page 2: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/2.jpg)
Learning Objective
• Understand the different types of Acute hepatic failure (AHF)• Acute Liver Failure (ALF)• Acute-on-Chronic Liver Failure (AoCLF)• Post-hepatectomy liver failure
• Appropriate therapies and support of the liver
• Role of transplantation and other advanced support
![Page 3: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/3.jpg)
ALF definition
Development of severe hepatic dysfunction within 6 months of the onset of symptoms in the absence of chronic liver disease• Acute Hepatitis with elevation AST/ALT• INR>1.5• Encephalopathy
Hyperacute, Acute or Subacute
![Page 4: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/4.jpg)
ALF
![Page 5: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/5.jpg)
Common causes of ALF
![Page 6: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/6.jpg)
AoCLF
Acute hepatic insult manifesting as jaundice and coagulopathy, complicated within 4 weeks by ascites +/- encephalopathy in a patient with previously chronic liver disease
Bil >85 μmol/L and INR >1.5 mandatory
AoCLF vs end stage CLF
![Page 7: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/7.jpg)
AoCLF
![Page 8: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/8.jpg)
Precipitants of AoCLF
![Page 9: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/9.jpg)
Post hepatectomy liver failure
Impaired ability of the liver to maintain its synthetic, excretory and detoxifying functions characterised by impaired coagulation and hyperbilirubinaemia on or after postoperative day 5.
50/50 definition - PT >50% and Bilirubin >50μmol/L
Grade A, B and C
![Page 10: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/10.jpg)
Caring for the liver patient
![Page 11: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/11.jpg)
Don’t forget the basics!
History and Examination
![Page 12: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/12.jpg)
Send bloods ++• FBC• Coag, fibrinogen, TEG/ROTEM• Biochemistry• LFTs and GGT• Paracetamol/salicylate level• Arterial ammonia• Blood gases (Lact/glucose)• β-HCG• Viral hepatitis serology• Autoimmune screen, copper and caeruloplasmin• AFP• HIV test
![Page 13: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/13.jpg)
Other investigations
• Liver US and doppler ASAP
• +/- CT/MRI
• Liver Bx?
![Page 14: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/14.jpg)
Management
![Page 15: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/15.jpg)
Good ICU Housekeeping• Stop hepatotoxic drugs• Optimise haemodynamics for oxygen delivery• Steriods?• CVC/Vascath/arterial line early with US. PAC?• Invasive ventilation +/- neuroprotection?• 30o head up• Early enteral nutrition (protein 1-1.5g/kg/day)• Stress ulcer prophylaxis (PPI)• Aperients• Antimicrobials• Glycaemic control
![Page 16: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/16.jpg)
Specific Rx
• Paracetamol – NAC• Budd Chiarri – Anticoagulation/TIPS• Autoimmune – Steroids• Acute Fatty Liver of pregnancy – Delivery
baby•Wilsons – Chelating agents• Lamivudine and Aciclovir
![Page 17: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/17.jpg)
Paracetamol OD• Common poisoning
• <1% cases of OD result in significant hepatotoxicty
• CYP450 convert paracetamol to NAPQI
• NAPQI EXTREMELY hepatotoxic
• Usually conjugated with hepatic glutathione
![Page 18: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/18.jpg)
Paracetamol OD
• Bad• Malnutrition, ETOH abuse, enzyme inducing drugs• Large staggered OD• Delayed presentation and initiation of NAC
• N-acetylcysteine augments glutathione levels
• NAC highly effective if delivered within 8-12hrs
• Prescott normogram used to determine risk
![Page 19: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/19.jpg)
Cardiovascular• Hyperdynamic and hypervolaemic
•Moderate incidence adrenal dysfunction
• CO monitoring and fluid responsiveness
• PAC • Right ventricular cardiomyopathy• Hepatopulmonary shunt and pulm Ht
• Noradrenaline
![Page 20: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/20.jpg)
Variceal bleed• Restore Blood volume• Correction of coagulopathy• Reduce portal vascular resistance• Terlipressin/octreotide• 5/7 Abx (Tazcoin/cephalosporin)
• PPI?• OGD• Banding• Glue• Stenting
• Sengstaken• TIPS
![Page 21: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/21.jpg)
Coagulopathy• Coagulation• Low fibrinogen• Low levels of II, V, VII, IX, X, APC, Protein C/S• Mixed fibrinolytic/antifibrinolytic effects
• ‘Auto-anticoagulation’ vs prothrombotic• NO routine correction of INR (incl for lines)• Thromboelastometry helpful (TEG vs ROTEM) • Everything changes if bleeding • Generally platelets/fib 1st• FFP/cyro vs PCC/FCC• TXA and Calcium
![Page 22: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/22.jpg)
Ventilation
• Hepatopulmonary syndrome and shunting• Pulmonary hypertension may need ↓PVR• IAH/IACS
• Early intubation for Grade III/IV HE• Neuroprotection vs standard ARDsnet• LRTI/VAP common, low threshold for Abx• Consider paracentesis in IACS
![Page 23: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/23.jpg)
Encephalopathy and cerebral oedema
• Common in ALF and grade III/IV HE and NH4 >150• Cytotoxic and vasogenic/hyperaemic in origin• Poor autoregulation• ICP>25mmHg and CPP<50mmHg bad prognosis• Sepsis/SIRS detrimental• Reverse Jugular venous oximetry • ICP bolt risk vs benefit• TBI like ICP management• NO evidence for neuromonitoring• CRRT/plasma exchange
![Page 24: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/24.jpg)
Hepatorenal Syndrome• Not the commonest cause of AKI in AHF• ATN/nephrotoxic drugs/glomerulonephritis/IACS
• HRS diagnosis of exclusion• Type 1 vs Type 2• Results from reduced perfusion• Splanchnic vasodilation• Poor autoregulation • ↓ renal prostaglandin synthesis and other vasoactive mediators
• HAS/terlipressin• Early CRRT
![Page 25: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/25.jpg)
Renal Replacement Therapy• Haemofiltration vs HD/HDF?
• Some low level evidence for NH4+ clearance
• Start early
• Esp if Grade III/IV HE and NH4+>150
• Aim for dose of 35ml/kg/hr (Calculated vs actual dose received?)
• No evidence for high volume haemofiltration
![Page 26: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/26.jpg)
Microbiology• Highly susceptible to infection (LRTI/SBP/urinary/lines/wounds)
• SIRS/hyperdynamic/endotoxin translocation vs Bacteraemia
• Proven rates of 80% bacterial and 30% fungal
• Gram +ve in 1st 3-4 days followed by gram –ve and fungal infections
• Prophylaxis offers no mortality benefit
• Maintain high vigilance
• Refer to local guidelines and micro team
![Page 27: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/27.jpg)
ALF transplant Criteria• Paracemol vs non paracetamol• King’s college criteria
• Paracetamol• pH <7.3 >24hrs post overdose• Grade III/IV HE + Creat >300 + PT >100s
• Non Paracetamol• pH <7.3 or PT >100s• HE III/IV with any 3 of the following
• Age <10 or >40• Bil >300• Jaundice to HE time <7 days• PT >50s• Seronegative hepatitis or drug induced
![Page 28: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/28.jpg)
Transplant• Multidisciplinary decision
• Specialised service managed at supraregional centres
• If in doubt=refer/discuss
• Outcomes from transplant depend on ALF vs AoCLF vs CLF
• Live donor vs DBD vs DCD. Orthotopic and Domino Tx
• Complex anaesthetic+++
• Protocolised ICU post op management • TEM guided coagulation (balance bleeding vs HA/anastomosis flow)• Antibiotics• Immunomodulation• Early US and dopplers• MDT approach
![Page 29: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/29.jpg)
Artificial Liver Support• Bridge to transplant or recovery?
• Evidence?
• Detoxifying systems• Albumin dialysis• MARS (albumin dialysis/detoxifying and de-ionising columns)• Plasmaphoresis with FFP promising in ALF
• Bioartificial Systems• Extracorporeal liver perfusion old technology• Other systems using hepatocytes• ELAD study pending publication
![Page 30: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/30.jpg)
Questions?
![Page 31: Acute hepatic failure](https://reader035.vdocuments.net/reader035/viewer/2022062319/554af586b4c905fc0e8b48ad/html5/thumbnails/31.jpg)
Conclusion
• Don’t forget the basics• Resuscitate the patient • Good ICU house keeping• ALF vs AoCLF vs CLF• Antidotes/Specific Rx where appropriate• Complex/systemic disease with multi-organ
effects • EARLY referral/discussion with a liver unit