acute-liver-failure.ppt

,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,Acute Liver Failure,Dr.Eduardo Martinez,Foie gras,(pronounced,/fwr/,in English;,French,for fat liver)is a,food product,made of the,liver,of a,duck,or,goose,that has been specially fattened.,Foie Gras,Metabolic,Carb metabolism,Protein and lipoprotein metabolism,Fatty acid metabolism,Biotransformation of drugs,Storage,Glycogen,Vitamins A,D,E,and K,Iron and copper,Functions of the Liver,ALF,Syndrome that leads to MOF and death,Previously normal liver may fail within days,High grade encephalopathy,survival is 50%necrosis assoc.with poor prognosis,Need to reverse coagulopathy before doing it,Pathophysiology,Decreased intravascular volume,Kidneys try to“compensate”and retain Na+and water making oedema worse,Also,Gut-derived toxins reach the liver,Ammonia levels are often high,Correlation between ammonia and symptoms is poor,Clinical Features,Depend on the severity,which depends on:,Etiology,Speed of onset of symptoms,Non-specific,N&V,abdo pain,Neurological,Confusion,agitation,coma,Clinical Features,Mortality is higher for Grade III/IV,Mostly due to cerebral oedema,Occurs in 80%of pts.w/ALF,Due to lack of equilibration of osmotic gradient,30%of those have cerebellar tonsil and/or temporal lobe herniation causing death,Were now better at treating cerebral oedema,Clinical Features,Elevated ICP,HTN,bradycardia,blown pupils:occur late,CTB wont tell you,ICP monitor is best way of knowing,CVS changes,Similar to sepsis,Might be due to infection,Clinical Features,Renal failure,Oliguric,Poor prognosis,Except with paracetamol overdose where it has a good prognosis,Impaired immunity,Decreased complement synthesis,Kupffer cell dysfunction,poor neutrophil adhesion and superoxide production,Clinical Features,Increased susceptibility to infection,80%of pts.have bacteriologically proven infections,Major sepsis is contributor to death in 20%of cases,Staph.aureus 70%of gram(+),E.Coli most common gram(-),C.albicans in 30%of pts.,Monitoring,Pts.need HDU/ICU,Need CVC and continuous IBP monitoring and IDC,Baseline ABG and lactate,Lactate 3mmo/L after adequate resus has same sensi.and speci.for death as The Kings College Hospital criteria,KCH Criteria,Patients with paracetamol toxicity,pH 100s,Serum creatininelevel 300 mol/l,Grade III or IVencephalopathy,Other patients,Prothrombin time 100 seconds or,Three of the following variables,:,Age 40 yr,Jaundice 7 days before encephalopathy,PT 50s,Bilirubin 300mmol/L,Positive predictive value for ICU death without transplantation of 0.98,Negative predictive value of 0.82,KCH Criteria,Treatment,Adult U.S.Acute Liver Failure Study Group,Data from,23 liver transplant centers,1,110 pts.,In 2005 convened to,review literature on management,Care of pts.w/high ICPs,Compare practices of different centers,General Management,Admit to hospital and HDU/ICU,When evidence of ALF,E.g.:INR1.5,D/W:,Physician,Intensivist,Nearest transplant center,Regarding best time to refer,General Management,NAC,150mg/kg IV in 200ml NS over 15-60mins,50mg/kg IV over 4hrs,100mg/kg IV over 16hrs,Total dose:300mg/kg over 20hrs,Infusion recommended until there is evidence of improved hepatic function rather than time or paracetamol levels,Management of Complications,Hepatic encephalopathy and hyperammonaemia,Infections,Sedation and analgesia,Bleeding diathesis,Nutrition,Seizures,Circulatory dysfunction,Encephalopathy,Standard treatment:,Lactulose,Watch for:,Abdo distension,Oesophageal varices will need a scope,Avoid intravascular depletion,Non-absorbable ATBs,Neomycin,not recommended by ALFSG because of nephrotoxicity,Infection prophylaxis and surveillance,Infection is one of main causes of death in ALF,Most common sites:,Lung,Urinary tract,Blood,Most common M.O.,Gram(+)cocci:Staph aureus,Gram(-)rods:E.coli,Fungi:candida,Infection prophylaxis and surveillance,Empirical ATBs are recommended by ALFSG when:,Surveillance cultures reveal significant isolates,Advanced stage(III/IV)encephalopathy,Refractory hypotension,SIRS,3rd gen.Cephalosporin or Timentin,Vancomycin,Fluconazole,Sedation and analgesia,Agitation contributes to raised ICP,Propofol vs.Benzos,Both increase GABA neurotransmission,therefore may exacerbate encephalopathy,Propofol decreases ICP and wears off quickly,Opioids,Shorter acting are preferable,When there is concommitant ARF,avoid morphine or pethidine due to metabolite accumulation,Correction of bleeding diathesis,Pts.with ALF are by definition coagulopathic,Low plts.and fibrinogen,Vit.K deficient,Spontaneous bleeding is rare,Very difficult to obtain complete correction,ALFSG recommends aiming for:,INR 1.5,Plts.50,000,Correction of bleeding diathesis,Prophylactic FFP not recommended,Obscures the trend of PT as prognostic marker,Cryo recommended when fibrinogen low,When FFP fails to correct PT/INR,then recombinant factor VIIa can be given,Should be given before planned procedures,Avoid in patients with risk of thrombotic complication,MI,DVTs,etc.,Correction of bleeding diathesis,UGI bleeding,reduced by H2 antagonists or PPIs,TEDS and Scuds,Nutrition,ALF is a catabolic state,Negative nitrogen balance,Immunodeficiency,Enteral nutrition when possible,Hi-cal,Avoid free water and hypo-osmolarity,TPN when:,Specific contraindication for enteral feeds,Seizure Prophylaxis and Surveillance,Nonconvulsive seizure activity is common,Prophylactic antiepileptics not recommended,EEG when:,Grade II/IV encephalopathy,Sudden neuro deterioration,Myoclonus,To titrate use of barbiturates,Tx.,Phenytoin,Propofol,midaz,barbiturates,CVS Dysfunction,Correct hypovolaemia before starting vasopressors,Pressors needed for hypotension and low CPP,Norad is first line,can give high dose dopamine,Adrenaline may compromise HBF,Vasopressin not recommended because directly causes cerebral vasodilation and high ICPs,Medium doses of steroid may improve pressor response,Mx.of Cerebral Oedema and Intracranial Hypertension,Raised ICP due to cerebral oedema is one of major causes of M&M,CTB for Grade III/IV,To rule out anything else,i.e.bleed,ICP monitor,Grade III/IV encephalopathy,To,optimize,CPP,Not routine,Raised ICP,Aim for,ICP25mmHg,CPP 50-80,General recommendations,Keep it quiet,minimize chest physio and ETT suctioning,head at 30o,Dont treat spontaneous hyperventilation,keep PaCO2 35-40mmHg,treat fever aggressively with physical measures,Raised ICP,Specific management,Manitol,:first line therapy,Hypertonic Saline,Induced hypothermia,Barbiturate coma,Indomethacin:25mg IV over 1min.,Mechanical Ventilation,When to intubate:,Respiratory failure,Airway protection in advanced encephalopathy,Agitation,Imminent ICP monitor placement,Mechanical Ventilation,Pts.w/ALF often develop ALI/ARDS,Follow ARDSNet protocol,Avoid high PEEP,Use the minimum needed,CRRT,Indicated for:,Renal failure,Fluid overload,Metabolic derangements,Need to create space for IV colloids,i.e.FFP,CRRT preferred over IRRT,HD instability common,CRRT,Use citrate over heparin,Monitor,ionized,calcium,Use bicarb buffer over lactate or citrate buffer,Liver wont be able to convert them to HCO3-,Avoid hyponatraemia,May exacerbate cerebral oedema,Orthotopic liver transplant is the definitive treatment for patients who meet the criteria,orthotopic,(rth-tpk),adj.,In the normal or usual position,1 yr.and 5 yr.survival of patients undergoing OLT for ALF is about 20%lower than elective cases for cirrhotic patients,Auxiliary liver transplantation is and alternative,Liver Transplant,Absolute contraindications,Overwhelming sepsis,Refractory hypotension,AIDS,Uncontrolled raised ICP with likely permanent damange,Liver Transplant,MARS:molecular absorption and recirculation system,Adaptation of haemodialysis,Blood is dialysed against 20%albumin,Shown to improve encephalopathy,renal function and haemodynamic parameters,The efficacy of this technique has not yet been studied,Hepatic assist devices,So,what have we learned?,Thank you!,