hepatobiliary pt 5: portosystemic shunt cont. & review Qs Flashcards
Portosystemic Shunt: less common clinical signs / findings - size? kidneys? eyes? testicles?
- Small for age and breed
- Can have prominent kidneys
- Copper coloured irises in cats
- Intact males can be cryptorchid
Portosystemic Shunt: Diagnosis - CBC findings
- Microcytosis
Portosystemic Shunt: Diagnosis - urinalysis findings
- Low USG
- Ammonium biurate crystals
Portosystemic Shunt: Diagnosis - serum biochem findings
- Decreased albumin / total protein
- Decreased urea
- Decreased cholesterol
- Decreased glucose
- Mild elevation in ALP and/or ALT
Portosystemic Shunt: Diagnosis - bile acids? ammonia?
- Elevated pre and post-prandial bile acids (often marked), majority
- Elevated NH3 (not widely available)
Portosystemic Shunt: radiograph findings
- Small liver, enlarged kidneys
- Lack of portal perfusion, insulin, glucagon, and other trophic factors
- Urate calculi often radiolucent
Portosystemic Shunt: abdominal ultrasound findings
- Identification of abnormal blood vessel
- Assessment for urate calculi
- Other ‘footprints’ can include small liver, renomegaly
Portosystemic Shunt - when can we use CT angiography for Dx? what is its use?
- Helpful when ultrasound does not identify PSS despite clinical suspicion
- Outlines shunt anatomy which can increase surgical success
Portosystemic Shunt: Treatment options overview
- Initial stabilization for dogs with hepatic encephalopathy
- Long-term treatment of PSS:
> Surgical correction
> Medical management
Hepatic Encephalopathy: Treatment - 3 goals
- Alleviate neurologic signs
- Reduce incidence of predisposing factors
- Identify underlying hepatic condition for specific management
hepatic encephalopathy diet therapy considerations, esp protein and fiber
- Most dogs can have normal protein levels
- Feeding smaller, more frequent meals helps decrease protein load at once,
maintains appropriate calorie/protein nutrition - Mild and temporary protein restriction might be required – only in severe cases
- Avoid protein malnutrition
> Body protein breakdown will cause elevation in NH3
> Monitor BCS and MCS carefully - Fibre in diet helps trap ammonia, other toxins in feces for evacuation, decreases contact time of feces & bacteria
> Decrease ammonia / other toxin production and absorption
HE: Medical Therapy options
- Lactulose
- Antibiotic therapy
- Reduce triggers of HE
> Inflammation, infection
what is lactulose and what is its use in treating HE?
- Soluble fibre
- Acidifies colonic contents and traps ammonium ion in colon
- Promotes ammonia incorporation into bacteria
- Hastens colonic transit time (reduced time/ability for toxin absorption)
() - 2.5 to 5ml (cat); 2.5 to 15 ml (dog) every 8 hours
- Titrate dose to produce 2-3 soft stools per day
antibiotic therapy for HE? purpose?
- Amoxicillin, or metronidazole
- Decrease bacterial populations
- Decreases amount of toxin production in the intestinal tract
preferred treatment option for HE due to shunt?
- Surgical attenuation of the shunt is the preferred treatment option (referral surgery)
- Medical management
> Treatment for hepatic encephalopathy