how many lobes does the liver have and where is it?
6 lobes, cr abdomen mostly under ribs, 2:3 left:right side
which part of the liver is easier to access? why?
deeply fissured on left side so easier to access this part (right is more attached an with more vascular involvement)
4 important things to consider about the sx anatomy of the liver
(1) Friable tissue (2) Requires different techniques compared to the ones used in other parenchymatous organs (3) Difficult hemostasis (4) 4.“Biliary leaks”
what is the blood supply like to the liver? (super general)
2 afferent supplies and one efferent (afferent is what comes to the liver)
what are the two afferent blood supplies to the liver? what is their pressure like and how much of the liver's blood supply is contributed by them?
(1) Portal system!! low pressure, 80% of the blood volume that enters the liver (50% of the oxygenation) (2) Arterial system, high pressure 20% (2 to 5 arteries), branches from hepatic artery (50% oxygenation)
what is the artery that supplies the gall bladder?
cystic artery for the GB (little branch of the hepatic artery)
where does the liver's nutrition come from?
how does blood exit the liver?
through the central veins--> hepatic vein--> Ca vena cava
what are some of the major liver functions?
Synthesis of plasma proteins, Maintenance of carbohydrates and lipid metabolism, Bile production, Coagulation factors (many coag factors need vit K-- and K is lipid soluble (need bile for fat to get K) ), Clearance organ (drugs and toxins), Hormone production (gastrin), Storage (vitamins, fat , glycogen, minerals)
what are some Liver characteristics?
Difficult to palpate, No signals of disease till an advanced stage, Hepatic failure affect many other systems: CNS, kidney, intestines, heart, coagulation, wound healing
can you live without the liver?
no, but can lose up to 70% of it and be fine
how do you know on a radiograph if the liver is small or big?
axis of the stomach- the axis of the stomach should be PARALLEL to the ribs
(1) DRUGS: talk to anesthesia. need drugs not going to specifically affect the liver (2) Coagulation profile, Blood type (hge common, have blood products avail, try to blood type) **Biliary obstruction alters vitamin K absorption (so might need some vit K on hand) (3) Antibiotics (most circulation to liver from portal vein, which came from intestines, so higher chance of contamination)
Abx--> what is a normal flora of the liver? how should you pick your abx based on this?
anaerobic flora normal inhabitant (Clostridium sp)--> Broad spectrum preferred
what approach will you use for liver sx?
(wide clipping, up to even part of thorax, wont know if you need to do paracostal incision or thoracotomy) ventral midline incision
what happens if there is Hge EVERYWHERE during liver sx-- what do you do?
Pringle Maneuver (more on other cards)
what is the Pringle Maneuver and how do you do it? what does it result in? how long can you do this for?
do for tx hge of liver during sx. This manuver occludes the portal triad put tip of finger into the epiploic foramen to occlude the portal triad- portal vein, hepatic artery, and common bile duct. You can do this for 20 minutes!!! (MAX!)
what are some different ways to obtain liver bx? (4)
take dermal punch tool, "punch" out pieces of the liver (affected lobs AND OTHER lobes) and then you have gel foam clotting foam and insert it into the dermal punch hole you've left behind (you can use dermal punch tool to pre-cut the foam you want to use) and then you can leave it there.
how do you do a wedge biopsy of the liveR?
cut a triangle from the edge of the lobe you are interested in, and then HORIZONTAL MATTRESS suture (*careful- dont crush parynchyma, it dehisses easily- just get to the point where you are apposing the edges)
how do you do a partial lobectomy?
first transect the liver capsule, then fracture the parynchyma with your fingers, then before we cut, ligate all the large BVs and bile ducts, and electrocauterize the small ones.
which lobes, if you are going to have to do a total lobectomy, which lobes must you handle very carefully, and why?
right lateral and caudal lobes require dissection around vena cava
how do you do a total lobectomy?
(remember, easier to remove a L lobe than a R bc L more detached.) right lateral and caudal lobes require dissection around the vena cava!! Use a Rummel tourniquet to hold vena cava away. Then you can use a stapler to ligate and remove, OR, if you have a L lobe which is well separated you can put circumferential ligatures/ligasures etc on the smaller hiluses. *dont just put only one circumferential lig around the liver lobe that would be unsafe
what are the possible complications of a total lobectomy?
Unknown etiology and Formation mechanism: little known
what are some of the components of Cholelithiasis?
Cholesterol, bilirrubin, Ca, Mg, oxalates....will see Early bilirrubinuria
WHO is prone to getting Cholelithiasis?
female, adult, small breed dogs
Gallbladder mucocele--> etiology? clinical signs?
etiology unknown (can be result of cholecystitis), clinical signs are vague GI signs
who is prone to a gallbladder mycocele? (breeds)
Cocker Spaniel, Shetland, Miniature Schnauzer
what is going on to cause a gallbladder mucocele?
gallbladder epithelium starts producing mucus (Can be bc of irritation)
what is the pathognomonic sign which points to a GB mucocele?
"kiwi sign" on ultrasound.
what is this, what does it mean?
This is the KIWI SIGN on ultrasound, pathognomonic for GB mucocele
what approach might be needed to sx access the GB?
how can pancrease problems and GB problems be related? who is this more of a problem in?
pancreatitis--> leak of enzymes--> turn fat into soap--> soap can block bile ducts. Also tumors. *In cats pancreatic pathology is the main cause
what are some things which can cause Extrahepatic biliary obstruction?
pancreatic pathology (esp cats), intra or extraluminal / mural neoplasias, ascending infection, necrotizing colecystitis. (can then have peritonitis-->sepsis)
If there has been trauma to the bile duct, or there is a stone blocking it, what can we do?
can go into bile duct, fix it, stent it (could be a red rubber catheter)-- insert the stent through a duodenostomy, then suture into place with dissolveable sutures (gonna have to suture ducts with magnifying glasses and 5-0 suture material). Sometimes, if you have a sent in, you will want to insert a choletocotomy tube to outside to relive some pressure (so can still drain to duodenum but if there is too much pressure it has somewhere to go.)
what is Cholecystotomy?
go in gall bladder, open it up, do what you gotta do (take out stones, bx), then close it
what is Cholecystectomy?
remove gall blader (but not the plumbing!)
what is Choledochotomy?
make incision to fish stone out of DUCT
what is Cholecystoduodenostomy/Cholecystojejunostomy? what are you doing?
SALVAGE PROCEDURE! Cholecystoduodenostomy/Cholecystojejunostomy-- make stoma in GB, attach gall bladder to either duo or jejuno. This is when there is no patentcy of the common bile duct but GB is healthy- make sure stoma not any smaller than 2.5 - 3 cm. long
how do you do a Cholecystotomy?
place stay sutures, open it up, go inside, always get a wall bx, close it up. When looking for stones always check patentcy of common bile duct, can do this but normograde or retrograde(would need a duodenostomy if retrograde)
how do you do a cholecystectomy?
(usually do if there is cholecystitis, or GB mucocele, it's full of stones, not viable..). Lapsponges an balfour retractors should be used. Can have stay sutures on the stomach to retract it caudally to try to see better, then try to dissect the GB out from the hepatic fissure/lobes (can be very difficult to do...she said you can do hydrodissection where you use stay sutures to pull up, and then use a stream of water to help peel the GB off the liver) dont forget about cystic artery (branch of L hepatic artery) which you will need to ligate!! along with the common bile duct of course.
what are biliary salts?
(stuff in GB) mildly irritating but sterile unless associated to hepatic disease. If there is death due to biliary peritonitis, that's because there was bacteria
how to dx biliary peritonitis?
DPL (95% accurate)
pathognomonic sign that there was leakage of bile into the abdomen?
organs will be tinted with a organge/bronze color, and will probably see jaundice in the MM also
what do if biliary peritonitis?
LAVAGE LAVAGE LAVAGE! Then can do open peritoneal drainage where you lavage, C/S, then close caudal 1/3 of abdomen and then leave the most cranial aspect open, then do eyelet sutures and then bandage (change bandage as much as needed until pt stops draining).