Westminster hepatic

hepatic lobule (50,000-100,000) (hepatocytes envelop central vein)

hepatic artery and portal vein, combined blood joins in hepatic sinusoidal channels. Endothelial cells and Kupffer's cells line the sinusoids.

from hepatic veins to IVF.

1500ml blood per minute, 25-30% from hepatic artery and 70-75% from portal vein. (25-30% of CO).

filter. 99% of bacterial load cleansed by Kupffer cells (macrophages)

Large (350ml) reservoir for systemic blood.

liver, gallbladder, omentum, spleen and pancreas

innervated b splanchnic nerves derived from spinal nerves T3-T11.

portal circulation; only alpha receptors,

hepatic arterial circulation: both alpha/beta.

Adequate liver oxygenation not an issue because of large percent of CO perfusion, great permeability of hepatic sinuses and the close proximity of hepatic cells to sinuses.

bacteria

kupffer cells(macrophages) line the hepatic sinuses

endothelial cells that line the hepatic sinuses allow diffusion of large plasma protiens and other substances into the extravascular spaces of the liver

protien

the low resistance of hepatic sinusoids

metabolic demand, i.e oxygen consumption


portal flow dependent on the combined venous outflow from the spleen and GI tract.

a decrease in one or the other affects a compensatory increase in the other.

sympathetic outflow from hypotension, hypovolemia, hypercarbia, hypoxia and light anesthesia.

abdominal surgery

ALL, especially halothane (25%) (abolishes vasocontrictor response to hypercarbia)

d/t decreased SBP...

30% drop in flow with sympathectomy with SAB, epidural

bile production
protein synthesis
glycogen storage
protein metabolism
insulin clearance
lactate conversion into glucose
drug metabolism/transformation

gluconeogenesis from lactate

and from AA's(alanine) and glycerol

glycogenolysis

poor insulin clearance, a decrease in glycogen capacities and impairment of gluconeogenesis

Bile

1 liter/day

from hepatocytes in liver

contains phospholipids, cholesterol conjugated bilirubin (the end product of hemoglobin metabolism), bile salts, and other substances.

stored and concentrated in the gallbladder

CCK, presence of fat and protien in the duodunem

assists in absorption of fat soluble vitamins (AEDK)

steattorhea, vik K deficiency and delayed removal of active drug metabolites

coagulopathy (2,7,9,10)

all factors made in liver except 8.

50% factor activity needed for normal clotting

a perturbation in bile production ultimately manifests as impaired production o f vit K dependent factors.

portal HTN

leads to splenomegaly

thrombocytopenia from plt sequestration

immunoglobulins

liver disease causes a decrease in plasma oncotic pressure and a decrease in drug binding(exaggeration of effects, esp with barbs)

larger non-depolarizer dose d/t increased VD

decreased plasma cholinesterase (esters, sux, miv)

synthesis of lipoprotiens
deamination of AA's into carbs and fats for ATP production though citric acid cycle oxidation
productin of urea for the removal of ammonia (formed by deaminiation and gut bacteria)

production of clotting factors (fibrinogen, prothrombin and others)