Hepatic Flashcards
What is the portal triad?
Hepatic artery, portal vein & bile duct
What is the portal triad?
Hepatic artery, portal vein & bile duct
Albumin level indicative of liver failure?
Pentothal dose with liver failure
Reduced
Acute liver disease & PT
> 14
Steps involved in coagulation?
Adhesion of platelets to vascular wall (requires Factor VIII:vWF), activation of platelets (requires thrombin - IIa), aggregation of platelets (requires ADP & TXA2), & production of fibrin (requires extrinsic, intrinsic & final common pathway)
What produces VIII:vWF
Endothelial cells
Cryoprecipitate contains what factors?
VIII, I & XIII - harvested from FFP
What medications render COX nonfunctional?
NSAIDS/ASA
What medications prevent ADP induced platelet aggregation?
Ticlid, PLAVIX, integrilin, reapro, aggrastat
What coagulation factors are not made in the liver?
III (tissue factor), IV (calcium), & VIII:vWF
What factors are vitamin k dependent?
2, 7, 9 & 10
What is platelet dysfunction from with liver disease?
Elevated pressure from portal hypertension sequesters platelets in spleen rendering them inactive & elevated fibrin degradation products
What is platelet dysfunction from with liver disease?
Elevated pressure from portal hypertension sequesters platelets in spleen rendering them inactive & elevated fibrin degredation products
Hepatic blood flow
Liver receives 25% of cardiac output – hepatic artery supplies 25-30% of blood & 45-50% of oxygen, portal vein supplies 70-75% of blood & 50-55% of oxygen
Pentothal dose with liver failure
Reduced
Acute liver disease & PT
> 14
Steps involved in coagulation?
Adhesion of platelets to vascular wall (requires Factor VIII:vWF), activation of platelets (requires thrombin - IIa), aggregation of platelets (requires ADP & TXA2), & production of fibrin (requires extrinsic, intrinsic & final common pathway)
What produces VIII:vWF
Endothelial cells
Cryoprecipitate contains what factors?
VIII, I & XIII - harvested from FFP
Post-hepatic dysfunction tests
High bili & increased alk phos – bile duct obstruction
What medications prevent ADP induced platelet aggregation?
Ticlid, PLAVIX, integrilin, reapro, aggrastat
Cholestatic Disease
Gall bladder disease - gall stone pancreatitis, rarely progresses to MODS
What factors are vitamin k dependent?
2, 7, 9 & 10
Coagulation cascade
Extrinsic: 3&7 (PT/INR), Intrinsic: VIII, IX, XI, XII (PTT), Common: X, V, II, I, XIII
What is platelet dysfunction from with liver disease?
Elevated pressure from portal hypertension sequesters platelets in spleen rendering them inactive & elevated fibrin degredation products
Drug metabolism & hepatic disease
Inability to metabolize drugs from decreased blood flow and inactivation of P450 increases half life, decreased cholinesterase will prolong succ, mivacurium & ester locals,
Hepatic blood flow
Liver receives 25% of cardiac output – hepatic artery supplies 25-30% of blood & 45-50% of oxygen, portal vein supplies 70-75% of blood & 50-55% of oxygen
Venous system of liver depends on what?
Cardiac output - flow is pressure dependent
Reciprocal flow of hepatic system
If venous system decreases flow, arterial system can compensate, volatiles may decrease this & result in ischemia
Things in anesthesia that may effect hepatic blood flow
Positive pressure ventilation decreases flow by increasing intrathoracic pressure, alpha stimulation causes constriction, regional >T10 decreases perfusion pressure
Pre-Hepatic dysfunction tests
Bilirubin- elevated from hemolysis, reabsorption of hematoma, PRBC admin & surgery
Intra-hepatic dysfunction tests
Reflects direct hepatocellular damage, results of toxic effects - aminotransferase spills into blood stream & AST/ALT will be elevated (though these can also be indicative of other organ function), use other tests with
Post-hepatic dysfunction tests
High bili & increased alk phos – bile duct obstruction
Parenchymal liver disease
Results in MODS, varices, etc (high pressure)- cirrhosis, will have high CO, low SVR, decreased FRC & renal perfusion, e-lyte issues, ascites, coagulopathies
Cholestatic Disease
Gall bladder disease - gall stone pancreatitis, rarely progresses to MODS
Coagulation issues & liver failure - treatment
Vitamin K, if unresponsive use FFP
MAC for ETOH acute vs chronic
Acute intoxication - require less anesthesia (additive depressant), RSI. Chronic intoxication requires more anesthesia - cross tolerance and P450 system enhanced
