Hepatic surgery Flashcards
How does the liver get its blood supply?
Hepatic artery, hepatic portal vein, hepatic vein
What is the function of the liver?
Synthesis proteins (albumin) Synthesis and activation of clotting factors Storage of fats, viatmins, glycogen, copper Degradation of toxins, ammonia, drugs Lipid metabolism Gastrointestinal function Carbohydrate metabolism (glucose) Reticuloendothelial function
What conditions take place if a patient has hepatic insufficiency?
Hypoproteinaemia
Hypoglycemia
Coagulopathy
Hepatic encephalopathy
How should you assess the haemotological system in liver disease and how do you treat before surgery?
Assess clotting times APTT PT
Consider pre-treatment with vitamin K or fresh frozen plasma
Are antibiotics indicated for liver surgery?
Yes
Anaerobic bacteria within the liver, give peri-operative intra-venous antibiotics
Sample areas of the liver for culture
How do you take samples of the liver?
Ultrasound guided FNA, tru-cut biopsy Surgical biopsy (more accurate, potentially safer, laproscopic)
What are the indications for a liver lobectomy?
Neoplasm- benign, malignant
Biopsy/removal of lesion
Liver lobe torsion
abscess
What are the risks of a liver lobectomy and how much of the liver can you remove?
Haemorrhage blood type!
70% of the liver
What are the indications for biliary tract surgery?
Extrahepatic biliary obstruction -choleithiasis (gall stones) -gall bladder mucocele -pancreatits -neoplasia Biliary tract rupture and bile peritonits -trauma -disease process (cholecystitis, inflammation of the gall bladder)
What are the clinical signs of liver disease?
Non-specific Vomiting Icterus annorexia Abdominal pain Hypovolaemia shock (severe EHBO or bile peritonitis)
What parameters show up on haemotology and biochemistry as abnormal in liver disease?
ALT and ALP raised Decreased albumin Increased cholesterol and bilirubin Bile facilitates the absorption of vitamin k Coagulation abnormalities (DIC)
A patient has severe liver dysfunction leading to coagulation abnormalities what can you give to treat this?
Vitamin k-three doses at 0.5-1.5mg/kg s/c or im
Frozen plasma in emergencies 10ml/kg
What can cause bile peritonitis and how is it treated?
Trauma vs biliary tract disease
sterile vs septic
manage peritonitis
treat underlying cause
What are the two types of biliary surgery and what is important to consider?
Cholecystectomy-Surgical removal of the gall bladder
Cholecystoeneterostomy- Gall bladder is joined to the small intestine
Better to preserve the common bile duct rather than the gall bladder
What is the outcome for patients undergoing biliary surgery?
Systemically unwell
intensive post-op care monitor bile leakage, sepsis, SIRS
Significant mortality
cats poor prognosis for neoplasia
What should you include in the post-operative care of a patient undergoing biliary surgery?
Analgesia Keep close eye on clotting times Temperature Blood pressure signs of haemorrhage (PCV, TS, MM, CRT) Signs of bile leakage (peritonitis) Sepsis SIRS
What is a congenital portosystemic shunt?
Persistence of a vein travelling between the hepatic portal vein before it has reached the liver to the vena cava
What are the affected breeds of a porto-systemic shunt
Extrahepatic -westies -cairns -yorkshire Intraheptaic -labs -irish wolfhounds -Australian cattle dogs
What are the clinical signs of a portosystemic shunt?
Shunted growth Obtunded Seizures Hepatic encephalopathy high ammonia Urinary tract signs Gastrointestinal signs Drug intolerance
What investigations should be completed to look for a portosystemic shunt?
Signalment and history
Blood tests
imaging
What haemotology parameters may be abnormal for a portosystemic shunt?
non-specific
anaemia
microsytosis
What biochemistry parameters may be abnormal in a portosystemic shunt case?
Decreased urea Decreased albumin Decreased cholesterol Hypoglycemia increased ALT and ALP
What urinalysis parameters may be abnormal for a portosystemic shunt?
USG decreased
ammonium biurate crystalluria
What liver specific tests can you carry out to assess for a portosystemic shunt?
Ammonia-converted to urea in the liver, abnormal 80% portosystemic shunt cases
Bile acids
most useful test 100% sensitive
What imaging is useful to observe for a portosystemic shunt?
Ultrasound
Portovenography
-intraoperative under fluroscope guidance
-provides information on shunt configuration
-information of intra-hepatic vascularture
-confirms diagnosis
What is the medical management of a portosystemic shunt?
Retaining lactulose enema (removes ammonia)
Restricted protein diet
antibiotics
seizure medication
Is surgery recommended vs medical management in the portosystemic shunt?
Yes
Much better survival rates
medically manage 2-3 weeks before surgery
What are the goals of portosystemic shunt surgery?
To ligate the shunt
Restore normal portal blood flow
resolve hepatic insufficiency and clinical signs
What is the concern with complete ligation of the portosystemic shunt and how may it be avoided?
Liver hypertension
Partial ligation is an option
Gradual attenuation devices available
-ameroid constrictor, cellophane band, intravascular coil
How is portovenography carried out?
Contrast is injected into the jejunal vessel during surgery under fluoroscopic guidance
What are the complications with portosystemic shunt surgery?
portal hypertension haemorrhage GI bleeding neurological complications (don't arise straight away take a few days) Hypoglycemia mortality
What are the outcomes for portosystemic shunt surgery?
Better prognosis for extrahepatic
84-94% good
Intrahepatic 50-100%
Complete attenuation better clinical outcome
