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Critical Care Aspects of Chronic Critical Care Aspects of Chronic Hepatic FailureHepatic Failure
Aditya N. Dubey, MDAditya N. Dubey, MD
Peter K. Linden, MDPeter K. Linden, MDUniversity of Pittsburgh Medical Center
Department Critical Care Medicine
Learning ObjectivesLearning Objectives
Be familiar with the complications of chronic liver failure requiring critical care support
Pathophysiology and clinical sequelae of portal hypertension
Urgent treatments for variceal hemorrhage
Strategies to treat diuretic refractory ascites
Diagnosis, treatment, and prevention of SBP
Management of hepatorenal syndrome
Causes and treatment of hepatic encephalopathy
Indications for referral for liver transplantation
Hepatic FailureHepatic Failure
Major Reasons for ICU Admission
Variceal hemorrhage
Encephalopathy
Refractory ascites
Spontaneous bacterial peritonitis
Hepatorenal syndrome
Portal HypertensionPortal Hypertension
Terminology
Portal pressure = PV inflow x outflow resistance
The trans-hepatic gradient (THG) can be measured by the difference between the free hepatic vein to a wedge pressure in the hepatic vein (estimated PV pressure)
THG = free HVP – wedged HVP
Normal gradient < 5 mm Hg
Increased risk of bleeding > 12 mm Hg
Portal hypertension may be elevated without intrinsic liver disease due to pre- and post-sinusoidal pathology (see next slide).
Causes of Portal HypertensionCauses of Portal Hypertension
LIVER
Pre-sinusoidal PV thrombosis PV extrinsic comp. Schistosomiasis Sarcoidosis PBC
Sinusoidal Cirrhosis Alcoholic hepatitis
Post Sinusoidal Budd – Chiari Veno-occlusive dis. Severe CHF Restrictive heart dis.
BLOOD FLOW
Variceal HemorrhageVariceal Hemorrhage
Incidence and Outcome
Gastroesophageal varices in 40 - 60% cirrhotics
Variceal hemorrhage occurs in 25 - 35% cirrhotics
30% of the initial bleeding episodes are fatal
70% have recurrent bleeding with a one-year survival ranging from 30 - 80%
Non-variceal pathology (ulcers, gastritis, mucosal tear) may cause bleeding in patients with known liver disease and portal hypertension.
Sharara and Rockey. N Engl J Med. 2001;345 (9); 669.
Variceal HemorrhageVariceal Hemorrhage
Initial evaluation and stabilization
Assessment of intravascular volume status• Blood pressure is unreliable indicator of volume status• Hematocrit does not reflect acute blood losses
Fluid resuscitation• Place twp large bore i.v.’s and/or a central venous catheter• Colloid or crystalloid titrated to parameters of perfusion• Cross-matched or O negative blood can be used
Endotracheal intubation prior to endoscopy for: • Uncontrolled bleeding• Altered mental status, severe agitation• Respiratory distress or depression
Hierarchal Treatment for Hierarchal Treatment for Variceal Bleeding Variceal Bleeding
Pharmacologic
Endoscopic
Radiologic shuntTIPSS
Surgical Shunt
Balloon Tamponade
Pharmacologic and endoscopic therapyare the usual 1st and
2nd interventions
Acute Variceal Hemorrhage: Acute Variceal Hemorrhage: PharmacotherapyPharmacotherapy
Octreotide• Synthetic analogue of somatostatin
• Decreases portal pressure and azygos blood flow
• Stops variceal bleed in 80% of the cases
• Efficacy is similar to endoscopic sclerotherapy and better than vasopressin
• 5-day course reduces bleeding after endoscopic therapy
• Can cause mild hyperglycemia and abdominal cramping
Vasopressin• Reduces portal pressure but causes myocardial and mesenteric ischemia
Terlipressin• Efficacy similar to endoscopic sclerotherapy and as effective as balloon
tamponade when used with nitroglycerin
• Not approved for use in U.S.
Corley DA. Gastroenterology. 2001;120(4):946-54; Harry R. Curr Opin Crit Care. 2002;8:164-170; Sharara and Rockey. N Engl J
Med. 2001;345(9):669.
Possible Targets for Therapeutic Possible Targets for Therapeutic Intervention in Variceal HemorrhageIntervention in Variceal Hemorrhage
1. Reduction of cardiac output by beta-1 blockade to prevent bleeding (NOT for acute bleeding!!)
2. Reduction of splanchnic blood flow by beta-2 blockade or vasoconstrictors such as alpha-adrenergic agonists or vasopressin analogues
3. Reduction of intrahepatic resistance by vasodilators
4. Reduction of variceal or collateral flow by beta-2 blockade, balloon tamponade, or endoscopic therapy
Esophageal vs. Gastric VaricesEsophageal vs. Gastric Varices
Esophageal varices• Primary approach is endoscopic
banding or sclerotherapy
• TIPSS, surgical shunts are
alternatives
Gastric varices• Diffuse, deep submucosal
anatomy
• Endoscopic tx difficult, dangerous
• Primary approach are TIPSS or surgery
Variceal Hemorrhage: Endoscopic TherapyVariceal Hemorrhage: Endoscopic Therapy
Endoscopic Band Ligation (see next slide)• Controls bleeding in 80 - 90% of cases
• Lower complication rates than sclerotherapy
Endoscopic Sclerotherapy• Intravariceal or paravariceal injection of a sclerosing agent
• Stops bleeding in 80 to 90% of the cases
• Complications include perforation, ulceration and stricture
Cyanoacrylate Injection• Used to control bleeding from gastric varices
• Superior to EBL for treatment of bleeding gastric varices
• Not available in U.S.
Laine L. Ann Intern Med. 1995;123(4):280-7.
Lo GH. Hepatology. 2001;33:421-427.
Banding of Esophageal VarixBanding of Esophageal Varix
Post endoscopy problems include…Post endoscopy problems include…
Abdominal distension: From endoscopic air insufflation, retained luminal blood, and increased ascites from resuscitation. This can even progress to abdominal compartment syndrome with associated respiratory compromise, hypotension, oliguria, and acidosis. Nasogastric decompression may partially
alleviate this problem.
Worsening encephalopathy: This may occur due to gastrointestinal passage of blood, hepatic hypoperfusion (“shock liver), and accumulation of sedative medication.
Recurrent bleeding: More likely to recur in advanced cirrhosis. Incidence can be reduced with a 5-day course of octreotide post banding and long term use of a
non-selective beta blocker (propanol, naldolol).
Infection: Spontaneous bacterial peritonitis is 3-5x higher following variceal hemorrhage due to occult bacteremia and ascites seeding. Antimicrobial
prophylaxis (quinolone, beta-lactam) reduces the incidence of SBP significantly.
Acute Variceal HemorrhageAcute Variceal HemorrhageBalloon TamponadeBalloon Tamponade
Effectively controls bleeding in 90% of the patients but is only a temporizing measure in massive uncontrolled variceal hemorrhage when initial endoscopic treatment is delayed or unsuccessful. • Can cause aspiration, esophageal ulceration, perforation with
mediastinitis
• Balloon-related mortality is 3 - 5%
• Gastric balloon inflation is usually sufficient
• Esophageal balloon inflation should only be used when gastric balloon is unsuccessful as it is associated with higher morbidity.
Sengstaken – Blakemore TubeSengstaken – Blakemore Tube
Gastric balloon
Esophageal balloon
Gastric aspiration port
Minnesota TubeMinnesota Tube
Gastric balloon
Esophageal balloon
Gastric aspiration port
Esophageal aspirationport
Tube Positioning and Gastric Balloon InflationTube Positioning and Gastric Balloon Inflation
1. Tube inserted to 50 cm
2. Auscultate in stomach
3. Inflate gastric balloon with 50 cc
4. Stat portable film
1. Re-confirm proximal position
2. Inflate GB 300-400 cc air
3. Pull to insure anchorage
4. Recheck film
5. 1-2 lbs of pully traction
Gastric and Esophageal Balloon InflationGastric and Esophageal Balloon Inflation
Esophageal Balloon inflated to 30 mmHg
1. Last resort
2. Deflate periodically
3. Use minimum effective pressure
4. Complication
- ulcer
- perforation
- stricture
Malposition of the Gastric Balloon of a Malposition of the Gastric Balloon of a Minnesota Tube Retroverted in the Distal Minnesota Tube Retroverted in the Distal
EsophagusEsophagus
Transjugular Intrahepatic Portosystemic Transjugular Intrahepatic Portosystemic Shunt (TIPSS)Shunt (TIPSS)
Major Indications
• Refractory variceal bleeding
• Refractory ascites, hydrothorax
• Radiologic insertion of a metallic shunt (8 -
12 mm diameter) which joins the hepatic and portal veins
• Target gradient (HV-PV) < 12 mmHg
• Restores hepatopedal flow
• Decompression of varices
Summary of Trials Comparing TIPSS to Summary of Trials Comparing TIPSS to Endoscopic Therapy for Variceal BleedingEndoscopic Therapy for Variceal Bleeding
Stanley. Lancet. 1997;350(9086):1235-1239.
Generally, higher rates of rebleeding were more common after Endoscopy treatment, while encephalopathy rates were higher in the
TIPSS groups
Complications of TIPSSComplications of TIPSS
Peri-procedure mortality of 1 - 2%• Intraperitoneal bleeding due to perforation of the hepatic capsule, hepatic,
or portal veins
• TIPSS embolization
• Acute right heart failure due to increased venous return to right heart
Later complications include recurrent bleeding due to TIPSS stenosis or thrombosis, infection, and hepatic encephalopathy.
Conditions Which May Contraindicate TIPSSConditions Which May Contraindicate TIPSS
This venogram shows an occlusive thrombus of the portal vein, which may make safe TIPSS placement
impossible.
This abdominal CT demonstrates a large hypodense hepatic lesion due to hepatocellular carcinoma in a very shrunken cirrhotic liver. Other contraindications include hepatic vein occlusion, heart failure or pulmonary hypertension, biliary obstruction, and
poorly controlled systemic infection.
TIPSS Thrombosis/StenosisTIPSS Thrombosis/Stenosis
Incidence 12 - 74%
Most likely within the first month
Symptoms - recurrent bleeding, ascites
Detection - Doppler ultrasound angiography (shows velocity gradient)
Treatment • Balloon dilatation
• Placement of TIPS shunt
Trans-TIPSS Embolization of Persistent VaricesTrans-TIPSS Embolization of Persistent Varices
Persistent variceal bleeding due to high flow collaterals despite a patent TIPS shunt may be coil-embolized radiologically via the TIPS shunt itself.
Acute Variceal Hemorrhage: SurgeryAcute Variceal Hemorrhage: Surgery
The distal splenorenal shunt (Warren shunt) procedure is generally reserved for Child’s A or B cirrhotics.
Consider in patients with bleeding refractory to pharmacologic, endoscopic, and radiologic treatment.
Complications include shunt thrombosis, infection, and worsening encephalopathy.
30-day mortality is close to 80% in Child’s C patients requiring emergency shunt surgery.
Relative Effectiveness of Available Therapies for Relative Effectiveness of Available Therapies for
the Prevention of Recurrent Variceal Bleedingthe Prevention of Recurrent Variceal Bleeding
Beta-blockers are the single most effective and safest strategy to prevent the recurrence of variceal Bleeding.
More aggressive strategies such as banding, TIPSS, or shunt surgery may decrease bleeding but are associatedwith higher risks and costs.
Sharara A, et al. N Engl J Med. 2001.
Hepatic EncephalopathyHepatic Encephalopathy
Hepatic encephalopathy reflects a spectrum of neuropsychiatric abnormalities seen in patients with liver dysfunction after exclusion of other known brain disease.
Hepatic Encephalopathy – West Haven Hepatic Encephalopathy – West Haven Criteria for Grading Mental StateCriteria for Grading Mental State
Grade 1• Trivial lack of awareness• Euphoria or anxiety• Shortened attention span• Impaired performance of addition
Grade 2• Lethargy or apathy• Minimal disorientation for time or place• Subtle personality change• Inappropriate behavior• Impaired performance of subtraction
Grade 3• Somnolence to semi-stupor but responsive to verbal stimuli• Confusion • Gross disorientation
Grade 4• Coma, unresponsive to verbal or noxious stimuli
Hepatic Encephalopathy: Differential Hepatic Encephalopathy: Differential DiagnosisDiagnosis
Metabolic encephalopathies• Hypoglycemia• Hypoxia• Uremia• Electrolyte abnormalities
Toxic encephalopathies• Alcohol• Barbiturates, other CNS depressants• Heavy metals
Intracranial lesions• Subarachnoid, subdural, or intracerebral hemorrhage• Stroke• Intracranial tumor• Intracranial abscess• Epilepsy
Neuropsychiatric disorders
Hepatic Encephalopathy: Hepatic Encephalopathy: Precipitating FactorsPrecipitating Factors
Increased ammonia production• Gastrointestinal hemorrhage• Excess dietary protein• Azotemia• Infection including SBP• Blood transfusion• Hypokalemia• Systemic alkalosis• Constipation
Reduced metabolism of toxins because of hepatic hypoxia• Dehydration• Arterial hypotension• Anemia
Portosystemic shunts• Spontaneous
• TIPSS
• Surgical
Progressive hepatic
parenchymal damage
Hepatoma
Use of benzodiazepines or other psychoactive drugs
Riordan. N Engl J Med. 1997; 337(7):473-479.
Why does the ammonia level correlate Why does the ammonia level correlate poorly with encephalopathy?poorly with encephalopathy?
Venous ammonia levels < arterial
Time lag from ↑NH3 and CNS
Blood-brain permeability is variable
Balance of NH3 / NH4+
Processing (must be on ice, < 20 min)
Management of Hepatic EncephalopathyManagement of Hepatic Encephalopathy
First and foremost control the underlying precipitant(s).
Medical therapy - optimal agent is controversial (see meta-analysis)
Lactulose - has multiple actions including cathartic, acidification of the colon to
“ion-trap” ammonia as NH4+, and reduces inoculum of urea-splitting bacteria.
Drawbacks include osmotic diarrhea with hypernatremia due to free water loss
and gaseous bowel distension.
Neomycin - non-absorbed aminoglycoside which reduces colon bacterial
burden. Dosed at 2-6 grams orally per day. Small incidence of ototoxicity and
nephrotoxicity with prolonged usage.
Metronidazole - oral dosing at 800 mg/day. No large scale reported
experience. Is associated with neurotoxicity in hepatic failure due to
accumulation.
Flumazenil - benzodiazepine receptor (GABA) antagonist.
Flumazenil in Hepatic EncephalopathyFlumazenil in Hepatic Encephalopathy
In this double-blind, placebo-controlled, randomized trial,
flumazenil showed transient benefit in higher grades of
encephalopathy. The role of flumazenil for all degrees of encephalopathy or as a longer term agent in critically ill patients has not been determined.
Flumazenil
N = 265
Placebo
N = 262
Neurologic
improvement17.5% (Gr3)
14.7% (Gr4)
3.8% (Gr3)
2.7% (Gr4)
EEG
improvement27.8% (Gr3)
21.5% (Gr4)
5.0% (Gr3)
3.3% (Gr4)
Barbaro G, et al. Hepatology. 1998
Ascites - Critical Care AspectsAscites - Critical Care Aspects
Complicated ascites may be the principal reason for care admission but is frequently co-associated with intensive hemorrhage, renal failure, and/or hepatic encephalopathy.
Common complications of ascites include: • Diuretic-refractory ascites - defined as unresponsiveness to sodium
restriction and high-dose diuretics (400 mg/day spironolactone and 160 mg/day furosemide) OR rapid recurrence after therapeutic paracentesis
• Tense ascites - this may result in the development of:- Abdominal compartment syndrome with impaired venous return causing
hypotension, impaired renal perfusion causing oliguria and reduced hepatosplanchic perfusion
- Respiratory compromise may occur due to impaired diagphagmatic contractility and/or hydrothorax due to the passage of ascites into the pleural space
• Infection - (spontaneous bacterial peritonitis)
Runyon BA. Hepatology March 2004
ParacentesisParacentesis
Abdominal paracentesis is the most rapid and cost-effective technique to diagnose the cause of ascites. • An area of percussion dullness in the left lower quadrant (2 cm cephalad
and anterior to the anterior superior iliac spine) has a greater likelihood of ascites present than the midline.
• Ultrasound guidance should be utilized if ascites is difficult to localize and to avoid venous collaterals, intestine.
• Since bleeding is sufficiently uncommon, the prophylactic use of plasma or platelets before paracentesis is not recommended.
• An indwelling drainage catheter can be left for 3 - 5 days if therapeutic drainage is required.
Runyon BA. Hepatology. 2004.
Ascites - ClassificationAscites - Classification
High SAAG 1.1g/dl
Cirrhosis (75% cases)
Alcoholic hepatitis
Portal vein thrombosis
Budd-Chiari syndrome
Cardiac failure
Veno-occlusive disease
Low SAAG Low SAAG 1.1g/dl 1.1g/dl
Peritoneal carcinomatosis
Pancreatic ascites
Biliary ascites
Nephrotic syndrome
Tuberculous peritonitis
Krige J, et al. BMJ. 2001;322.
Spontaneous Bacterial PeritonitisSpontaneous Bacterial Peritonitis
Spontaneous infection of ascitic fluid in the absence of a secondary intra-abdominal source of infection
Translocation of intestinal bacteria or hematogenous seeding of ascites
Mainly a complication of cirrhotic ascites
Incidence is 15 - 20% of cirrhotics with the highest incidence in Child’s Class C cirrhosis and following upper gastrointestinal bleeding
E. coli, Klebsiella sp., S. pneumoniae most common
Clinical manifestations include fever, abdominal pain, unexplained encephalopathy, although asymptomatic presentations are not uncommon
Mortality per episode = 20 - 30%
One year follow-up mortality = 50%
Spontaneous Bacterial PeritonitisSpontaneous Bacterial PeritonitisDiagnosisDiagnosis
Ascites should be processed for the following:• Total cell count and differential
• Bacterial cultures in blood culture bottles
• Other tests (protein, albumin, LDH, glucose, special cultures) may be indicated based upon clinical judgment
A diagnosis of SBP is established by any one of the following:• > 250 polymorphonuclear cells per cubic mm of ascitic fluid and a
positive ascitic fluid culture is diagnostic.
• Patients with 250 PMN’s/mm3 but negative cultures (neutrocytic ascites)
• Positive ascites cultures and < 250 PMNs/mm3 (monomicrobial non-neutrocytic ascites)
Runyon BA. Hepatology. 2004.
Spontaneous Bacterial PeritonitisSpontaneous Bacterial PeritonitisTreatmentTreatment
Intravenous albumin 1.5g/kg at the time of diagnosis followed by 1g/kg on day 3 helps in preventing hepatorenal syndrome and decreases mortality (Sort P, et al. N Engl J Med. 1999;341:403-409)
Secondary bacterial peritonitis• PMN count 250 cells/mm3
• Multiple organisms on Gram’s stain and culture
• Two of the following ascites criteria:- Total protein > 1g/dl
- LDH > upper limit of normal for serum
- Glucose < 50mg/dl
• Treatment – Third generation cephalosporin and laparotomy
Spontaneous Bacterial PeritonitisSpontaneous Bacterial PeritonitisAASLD GuidelinesAASLD Guidelines
Patients with ascitic fliud PMN 250/mm should receive empiric antibiotic therapy e.g., cefotaxime, 2 g every 8 hours (I).
Patients with ascitic fliud PMN < 250/mm with signs or symptoms of infection should receive empiric antibiotics pending culture results (II-B).
Oral ofloxacin can be considered in patients without vomiting, shock, grade 2 hepatic encephalopathy, or serum creatinine > 3mg/dl.
Prevention of SBP:• Short-term (7 days) inpatient norfloxacin or bactrim prophylaxis in patients
with gastrointestinal hemorrhage
• Patients with prior SBP should receive long term prophylaxis with daily norfloxacin or bactrim (SBP recurs in up to 70% of cases within one year).
Refractory Ascites: ManagementRefractory Ascites: Management
Serial paracentesis every 2 to 4 weeks and/or transjugular intrahepatic portosystemic shunts:• Post-paracentesis volume expansion is controversial but may be
considered when 5 l or more of fluid is removed. Albumin (6-8 g per l of fluid removed), dextran 70 or hemacecel may be used.
A recent meta-analyses comparing TIPS vs. Paracentesis showed: • 30-day mortality - no difference, OR 1.0 (CI 0.1-10.06)
• 24-month mortality - no difference, OR 1.17 (CI 0.52-2.66)
• 12-month ascitic fluid reaccumulation - less in TIPS, OR 0.14 (CI 0.06-0.28)
• Hepatic encephalopathy - more with TIPS, OR 2.11 (CI 1.22-3.66)
• No difference in the incidence of GI bleed, infections, or acute renal failure.
Sheagren JN, et al. J Clin Gast. 1996; Saab S. Cochrane Hepato-Biliary Group. 2005.
Tc Labeled Sulfur Colloid Showing Fluid Tc Labeled Sulfur Colloid Showing Fluid Passage From Peritoneal to Pleural SpacePassage From Peritoneal to Pleural Space
9999
Bhattacharya, et al.J Gastroenterol Hepatol. 2001.
Right Hydrothorax Managed with Plerual Right Hydrothorax Managed with Plerual Catheter DrainageCatheter Drainage
Before After
Hepatorenal SyndromeHepatorenal Syndrome
• Type 1 HRS:
Acute impairment in renal function defined by doubling of initial serum creatinine above 2.5 mg/dl or a 50% reduction of the initial 24-hour creatinine clearance to a level lower than 20 ml/min in less than two weeks. Mortality is as high as 90% after 2 - 4 weeks
• Type 2 HRS:
Stable or slowly progressive impairment in renal function not meeting the above criteria. Associated with better survival than Type 1 HRS.
Hepatorenal SyndromeHepatorenal Syndrome
Pere Ginès, et al. N Engl J Med. 2004;350:1646-1654.
Hepatorenal SyndromeHepatorenal Syndrome
Criteria for Diagnosis of HRS:• Serum creatinine >1.5 mg/dl or 24-hr creatinine clearance < 40ml/min
• Absence of shock, ongoing bacterial infection or fluid loss, and no current treatment with nephrotoxic drugs
• Absence of sustained improvement in renal function (decrease in serum creatinine to 1.5mg/dl) after discontinuation of diuretics and trial of plasma expansion
• Absence of proteinuria (< 500 mg/d) or hematuria (< 50 RBCs per HPF)
• Absence of ultrasonographic evidence of obstructive uropathy or parenchymal renal disease
• Urinary sodium concentration < 10 mmol/L
Hepatorenal Syndrome: TreatmentHepatorenal Syndrome: Treatment
Administration of one of the following drugs or drug combinations can be considered:• Norepinephrine 0.5 - 3.0mg/h intravenously
• Midodrine 7.5 mg three times daily increased to 12.5 mg three times daily if needed in combination with octreotride 100 g subcutaneously three times daily, increased to 200 g three times daily if needed
Concomitant adminstration of albumin 1 g/kg intravenously on day one, followed by 20 - 40 g daily
This treatment is given for 5 to 15 days.
End point of the treatment is reduction of serum creatinine to < 1.5 mg/dl
Vasoconstrictor Studies in HRSVasoconstrictor Studies in HRS
STUDY Treatment # Pts HRS Reversal Survival Liver Tx
Guevara Or + A 8 4 5 -
Uriz Te + A 9 7 5 3
Gulberg Or, D, A 7 4 4 2
Mulkay Te + A 12 7 4 2
Ortega Te ± A 13 10 9 5
Angeli Mi,Oc,A 5 4 4 2
Duvoux NE + A 12 10 6 3
Moreau Te ± A 99 58 36 13
TOTAL 165 104 (63%) 73 (44%) 30 (18%)Or – orlipressin NE – norepinephrineTe - terlipressin OC - octreotide Mi - midodrine A - albumin
These results, although encouraging, need to be validated by a large, prospective randomized trial.
Hepatorenal Syndrome: TreatmentHepatorenal Syndrome: Treatment
Hemodialysis or continuous venovenous hemofiltration may be required as a bridge to liver transplant.
Liver transplantation offers the best survival rate of 70% at two years.
Kidney function may return to normal post successful
liver transplant.
Other Pulmonary Complications of Chronic Other Pulmonary Complications of Chronic Liver DiseaseLiver Disease
Hoeper MM, et al. Lancet. 2004;363(9419):1461-8.
Hepatopulmonary syndrome• Incidence of 4 - 29%• Diagnosis requires demonstration of hypoexmia due to abnormal intrapulmonary vascular dilatations
causing shunting or severe ventilation:perfusion mismatching. • Vascular dilatations demonstrable by either agitated saline echocardiography or macro-aggregated albumin
scanning. • Orthodeoxia (desaturation with upright posture) and platypnea (dyspnea with upright posture) may be seen.• Management include supplemental oxygen to maintain SaO2.• Mortality rate of 41% at 2.5 years reported. • Severe HPS may slowly remit after successful liver transplantation although supplemental oxygen required.
Portopulmonary hypertension• Incidence of 2 - 10% (as high as 16% in those referred for liver transplant)• Mean PA pressure > 25 mmHg, PVR > 250 dyne s-1 cm-5, PA occlusion (wedge) < 15 mmHg• Pathogenesis unclear but may include pulmonary arterial plexopathy in medium pulmonary arteries due to
shear stress or high output state or humoral influences.• Suspect in patients with progressive dyspnea and signs of right heart failure.• Continuous prostacyclin (PGI2) infusion has shown benefit in non-randomized, open label experience but
may not improve long term survival without liver transplantation. • Severe cases (mean PA > 45) or poor right heart function contraindicates liver transplantation.
Pathophysiology of Hypoxemia in Pathophysiology of Hypoxemia in Hepatopulmonary SyndromeHepatopulmonary Syndrome
Hoeper MM, et al. Lancet.2004;363(9419):1461-8.
Considerations for Liver Transplantation in Considerations for Liver Transplantation in Critically IllCritically Ill
Liver transplantation is the most effective treatment for chronic liver failure with an overall, one-year, 88% patient survival.
Patients with cirrhosis should be referred for transplantation when evidence of hepatic dysfunction or major complications develop.
Patients with type I HRS should have an expedited referral for liver transplantation.
The prognostic model for end stage liver disease (MELD score) predicts liver-related mortality based upon the serum Cr, serum bilirubin, and INR.
Murray K, Carithers R. AASLD Practice Guidelines: evaluation of the patient for liver transplantation. Hepatology. 2005.
Liver Transplantation