Liver 4

sihirlifil's version from 2018-04-11 23:51

Vascular diseases

Question Answer
How does patient presentation differ?NOT ICTERIC!
(acute or chronic/asymptomatic, hepatic encephalopathy, GI signs (esp melena), ascites)
What are the vascular liver diseases?PSS (congenital or acquired)
Arteriovenous malformations
Microvascular dysplasia/portal vein hypoplasia
(Ductal plate anomalies)
Congenital PSS can be…? (2)Extrahepatic (some vessels to liver, others bypass) or intrahepatic
Acquired PSS happens how?2ry to other liver disease --> cirrhosis --> blood flow backed up, portal hypertension
Special about congenital/developmental vascular diseases?There is overlap of these as syndromes! 1 patient may have multiple diseases
Are there breed dispositions for PSS?(remember small vs large breed)
Dx Congenital/Developmental: what are liver enzymes like for microvascular dysplasia (MVD) or portal vein hypoplasia (PVH)? what about PSS?Decreased fxn
MVD/PVH: mild ALT elevation (2x upper RR at most)
cPSS: no enzyme elevations!
Dx Congenital/Developmental: CBC? UA?CBC: microcytosis due to iron handling
UA: ammonium biurate crystals!!!
What’s this?
Ammonium biurate crystals! From UA
What happens with ammonia w/ a PSS?Some protein converted to ammonia by bacteria. Normally taken to liver by portal vein, but instead goes right into circulation if the vessel is bypassing it
Dx Congenital/Developmental: what do you see on abdominal rads?Microhepatica, renomegaly (kidneys can do 20% gluconeogenesis), cystoliths
Dx Congenital/Developmental: what do NORMAL bile acids tell you?100% sensitivity! so if normal = NO PSS!
Dx Congenital/Developmental: if bile acids are high, what do?Means they are in circulation & not getting recucled. So need to go further. Congenital intrahepatic vs. extrahepatic PSS or AV malformation; MVD/PVH; acquired shunts
Dx Congenital/Developmental: what if ammonia is HIGH? normal?HIGH: HE is due to shunting
Normal: does not rule out HE! (not helpful until already narrowed down dx)
Dx Congenital/Developmental: what does Protein C tell you?Does not dx PSS or MVD, but can help tell them apart when it’s down to PSS vs. MVD.
Dx Congenital/Developmental: If Protein C is low =PSS
Dx Congenital/Developmental: If Protein C is normal =MVD
Dx Congenital/Developmental: which advanced imaging tools can be used?US (can dx!
MRI~ ((gold std if availabile)

Exploratory laparotomy (for extrahepatic, since you can fix while you’re in there)

How do acquired shunts develop?Primary shunt --> liver development is abnormal --> progressive portal hypertension --> development of acquired shunts (adult dx of congenital dz)
How does hepatic encephalopathy develop?Protein metab + bacterial byproducts --> portal vein, then liver, then heart ---> BRAIN!
Neurotransmission & cerebral edema effects --> ANY brain neuro signs
ER Tx of HE: goal? how? (3)Decrease lvl of neurotoxins (ammonia + others) with lactulose, antibx, flumenazil
ER Tx of HE: How does lactulose work?Remove gut bacteria & decrease ammonia absorption
Give enema if patient not conscious
ER Tx of HE: How do antibx help?Reduce # of bacteria that are turning byproducts into ammonia
ER Tx of HE: which antibx?Metronidazole
Ampicillin or amoxacillin
Neomycin (NEPHROTOX so not for longterm!)
ER Tx of HE: How does flumazenil work?Reverse effects of endogenous benzodiazepines
ER Tx of HE: how to treat seizures?R/o hypoglycemia (if yes --> dextrose IV)
Low dose midazolam
Long-term Tx of HE: components (5)Lactulose, antibx, diet, proton pump inhibitor, nutraceuticals
Long-term Tx of HE: dose of lactulose? effects?Adjust dose (diff from emergency tx). Loose stool more frequent, but not D+
Long-term Tx of HE: same antibx as emergency?Yep! (but didn’t list ampicillin) but reduced dose of metronidazole
Long-term Tx of HE: what kind of diet?Low protein
Long-term Tx of HE: what’s the proton pump inhibitor for?Prevents gastric ulceration
Long-term Tx of HE: which nutraceuticals?Denemarin, ursodiol
Long-term Tx of HE: what should owners monitor for?CS of HE: circling, head-pressing, acting blind, seizures, abnormal behavior, extreme lethargy (esp after eating)
Melena (dark tarry stool)
Lower urinary tract signs
Congenital PSS: Pros & Cons of surgical correction?
Congenital PSS: Pros & Cons of medical management?
Congenital PSS: overall is sx or medical management recommended?(multiple studies, conflicting info) Surgery! Prognosis may not be that different, sx has better QOL
Congenital PSS: complications of surgerySeizures, portal hypertension; HE signs continue afterwards & still need meds
Congenical PSS: complications of medical management aloneProgressive cirrhosis, portal hypertension

End-stage liver disease

Question Answer
Treatment: IcterusUrsodiol
Treatment: Hepatic encephalopathyDiet, lactulose, antibx, proton pump inhibitor
Treatment: GI signs (esp melena)Proton pump inhibitor, anti-emetics
Treatment: AscitesSpironolactone (best for abdominal, as opposed to Furosemide for lungs), +/- therapeutic abdominocentesis
Treatment: CoagulopathyPlasma for clinical bleeding, Vit K supplement (don’t do pre-emptive!)
Prognosis of end stage liver disease?If ascites: 2 month median
No ascites: 6m-2y
Is this stage reversible?Nope! can’t reverse fibrosis & cirrhosis that’s already there. That’s why catching the asymptomatic patient is GOOD!