Liver Flashcards
What is the acinus
Microvascular unit of the liver. Hepatic arteriole, portal venule, bile ductile, and lymph vessels and nerves
Zone 1: ___ zone. Cells are closest to what, receive what, and major site of what
Periportal. Portal axis. Rich in oxygen. Oxidative metabolism and conversion of ammonia to urea
Zone 2: ____ ____. What it is
Midzonal region. Transition zone, anatomic reserve
Zone 3: ___ cells, at ___, receive blood that has what. Least what. Major site of
Pericentral. Margin of acinus. Has exchanged gases and metabolites w cells in zones 1 and 2. Least resistant to metabolic and anoxic damage. Cyp450 and anaerobic metab
SNS stim of liver __-__ does what
T3-11, inc hepatic vascular resistance (less blood vol), inc glycogenolysis and gluconeogenesis
PNS stim of liver does what
Increases glucose uptake and glycogen synthesis
Hepatic arterioles have a myogenic response that does what
Keeps local bf constant despite bp changes
What is the hepatic arterial buffer response
Portal venous flow dec- adenosine builds up- arteriolar res dec and arterial flow inc. portal venous flow inc- adenosine washed out- arteriolar res inc and hepatic arterial flow dec
Changes in __ or ___ of portal blood associated with inc in hepatic arterial flow
Ph or pa02
___ ___ increases hepatic arterial and portal venous flow
Postprandial hyperosmolarity
What does the IVC do that can lead to ascites
Pressures of 10-15 inc hepatic lymph flow, leads to sweating free fluid from liver to abd cavity
Anesthetics and liver disease impair what response
Ability of liver to decrease bf/vol in response to sns stim
Coag factors formed by liver
All except vwfIII, III, and IV
Vitamin k dependent factors made in liver
PT/factor II, VII, IX, X, proteins c and s
Opioid effects on sphincter of oddi antagonized by 5.
VAs, narcan, nitro, atropine, glucagon
Which zone of liver most vulnerable to toxic metabolites of tyelenol
Zone 3
What is intrinsic clearance
Fraction of delivered drug load that’s metabolized during a single pass thru liver
High clearance means what, which drugs 3
Hepatic clearance approaches the rates at which they transverse the liver. Lido, benadryl, metoprolol
Low clearance (IC) means what, ex of drugs 3
Hepatic clearance rel independent of hepatic bf. Diazepam, tyelenol, warfarin
4 tests of hepatocellular damage
AST, alt, ldh, gst
Assessments of bile flow (4)
Alk phos, 5 nucleotides, ggt, bilirubin
Assessment of hepatic synthetic function 2
Albumin, pt/inr
Idiosyncratic rxns leading to hepatitis 4
Nsaids, va, anti htn, anticonvulsants
Risk factors to halothane depatitis
Prior exposure, >40 y/o, obesity, female, Mexican, mult brief exposures with short duration, enzyme induction
% metabolism of volatile agents
Halothane 46%, enflurane 6%, sevo 3%, iso 1%, des .02%
Most to least: hepatic bf and oxygenation decrease w GA and VA
Hal, enf, des, iso, sevo
How nitrous effects liver
Inc sns- vasoconstrict sphlanchnic/portal flow. B12 deficiency (methionine synthase)
Alcoholic liver disease: 3 forms
Steatosis, alcoholic hepatitis, cirrhosis
Hallmark of end stage cirrhosis
Portal htn
Hyperdynamic circ in cirrhosis: ___ CO, ___ SVR, ___ BP, ___ filling pressures, ____ hr
Hi CO, low SVR, low/nml BP, nml/inc SV, nml filling pressures, hi/nml hr
Hepatopulm syndrome: intrapulm _____, type I v II
Shunting. I precapillary II arteriovenous
Hepatopulm syndrome: 0xyhgb curve shifts where. VQ mismatch leads to what
Right (inc 2,3 dpg). Imp HPV, pleural effusions, ascites, diaphragm dysfunction
Treatment of cirrhosis w portal htn and suites 5
Na and fluid restriction, diuretics (spironolactone or amigo ride), paracentesis
Cirrhosis renal abn: reduction in __ and __ excretion
Sodium and water
Hepatorenal synd: ____renal failure, ___ gfr, ___ renal tubular func and ___ renal histology
Pre, low, preserved, nml
Type 1 hepatorenal syndrome
Progressive oliguria, rapid creat rise, poor prognosis
Type 2 hepatorenal syndrome
Moderate, more stable impairment, in pts w refractory ascites
Hepatorenal treatment: aimed at what, 4 options
Reversing patho cause= sphlanchnic arterial vasodilation. AVP, octreotide, albumin, transplant
4 cirrhosis heme/coag abn
Anemia, dec vit k dep factors (long PT), thrombocytopenia and thrombopathy, dysfibrinogenemia
Endocrine disorders in cirrhosis
Dec ability of muscle to uptake insulin, inc GH and glucagon, hypoglycemia, feminization males/amenorrhea females
Factors assoc w hepatic encephalopathy 4
Inc ammonia produc, fluid/lyte/acid base imbalance generates ammonia, alt liver/brain func, reduced hepatic metabolism
3 overall fx of cirrhosis cholestatic disease
Cv dysfunction, coag disorders (vit k def), renal vulnerability
Cv effects of cholestatic disease
Imp contractility, less resp to NE/Isuprel/ang II, dec SVR, inc CO
MELD: what it is, how to calc
Non subjective factor risk score. Creatinine (adults w dialysis biweekly value=4) bilirubin, INR
Child Pugh score: what makes it up. What c means
Albumin, pt, inr, bilirubin, ascites, encephalopathy. Elective sx contraindicated
Ways to optimize liver pt preop
Correct etoh dependency, coagulopathy, ph, lyte abn (esp K), malnutrition, anemia, varicies, hepatic encephalopathy
How to correct PT/INR in liver pt, when. What for emergency
Few days prior. Vit k IV, factor VII, FFP in emergency
How benzos metab differently
Inc cerebral uptake, dec clearance, longer e 1/2
How precedex diff
Dec clearance, longer e 1/2
How propofol response dif, DOC w what
Single dose response similar, recovery may be longer post gtt. Encephalopathy
Morphine: e 1/2, PB, sedative and resp fx
Prolonged, decreased, exaggerated
Demerol: clearance, half life, SE
50% dec clearance, double e 1/2, neuro toxic
Fentanyl: clearance, effect of gtt
Decreased. Exaggerated fx
Sufentanil: kinetics, e 1/2
Similar. Infusions and repeat doses may prolong effect
Alfentanil: e 1/2, DOA, effects
Doubled, prolonged, enhanced
NMB: ____ Vd, ____ initial dose. Advanced disease reduces elim of: 4= inc DOA
Inc, higher. Vec, roc, panc, miva
2 NMB not dep on hepatic elim
Atra and cis
NMB fx prolonged in liver/why. ___ vd, ___ initial dose.
Sux. Dec cholinesterase levels. Inc, higher
Intra op: ____ response to catecholamines, why
Decreased. Circulating vasodilators (bile acid, glucagon)
Intra op: consider ___ dose of catecholamines or add ____ to support bp
Increased, vaso
Patients with biliary obstruction are intolerant of ___ ____
Blood loss
Assess what 4 things when deciding if CVP or PA placement for liver pt
Hypovolemia, abd compartment syndrome, distributive shock, CHF
Local/mac case: what is necessary to avoid which SE
Adequate sedation. Minimize SNS stim which could lead to dec hepatic bf/02
GA in liver pt: airway and gas options
RSI or awake ett. Sevo, iso doc. N20 ok
Which symptoms defined as fulminant hepatic failure
Encephalopathy within 2-8 weeks of symptoms w surgery
Hepatocellular causes of post op jaundice
Drugs (anesthetics), ischemia (shock, hypotension, sx retraction), viral hepatitis
What TIPS does on a basic level
Used for end stage liver pts to dec portal pressure and dec portal htn SE. connects PBF into hepatic vein
TIPS: anesthesia types, what if variceal bleed, pts typically have what
MAC unless long sx/sick then general. Resusc w fluid and blood. Severe coagulopathy
Concerns of what could happen in TIPS procedure
Ptx, neck vessel injury, cardiac dysrhythmias from catheter, hemorrhage, pulm edema and CHF w low cardiac reserve
Techniques other than fluid and blood to dec blood loss in hepatic resection
Pressers, intermittent portal triad clamp, ischemic pre conditioning
Hepatic resection: which position in OR and why
Modest t-berg, reduce intrahepatic venous p, inc preload and CO, reduce VAE risk
Hepatic resection postop: fluid type and why
IVF w phosphates to help liver regeneration and avoid hypophosphatemia
