Gastrointestinal Disease of the Horse Part II Flashcards
what percent of dehydration is clinically detectable?
only 5% and above
what can you use to evaluate hypoperfusion in laboratory tests?
lactate
creatinine
PCV/TS
urine specific gravity
cardiac filling pressure
blood pressure
what is elevated lactate?
> 2 mmol/L
what can cause marked hyperlactatemia (>4mmol/L)?
hypoperfusion
severe hypoxemia
severe anemia
can happen in absence of tissue hypoxia
in whom is PCV/TS potentially a poor indicator of circulatory status?
foals
what is the range of urine specific gravity in adult horses?
1.020-1.050
what can cause spurious hypercreatinemia?
placental dysfunction
perinatal asphyxia
what is perinatal asphyxia?
swallowing of fetal fluids
happens if under fetal distress
in whom is central venous or cardiac filling pressure useful for?
most for neonates
need a central line
a central venous pressure < ___________ may indicate a need for increased fluid therapy
2 cmH2O
what is the goal for central venous pressure of resuscitation?
8-12 cmH2O
what fluid rate is used for adults after resuscitation?
50-75 ml/kg/day
when are oral fluids better than intravenous fluids?
treatment of large colon disease
following water deprivation
does glucose and temperature of gastrointestinal fluid absorption matter?
minimal effect
are chronic colics commonly cardiovascularly stable?
yes
how common is equine gastric ulcer syndrome in adults?
80-90% active racehorses
up to 60% other performance horses
how long should you fast a horse before gastroscopy?
12-18 hours
what might a gastroscopy for equine gastric ulcer syndrome underestimate?
extent of gastric ulcers
severity or depth of squamous ulcers
may miss glandular or duodenal gastric ulcers
how does sucralfate work?
reacts with HCl: acid buffer
binds to proteins: protective barrier
absorbs bile acids
increases prostaglandin E
why are fresians thought to present with progressive dilation of the stomach?
primary neurological or structural dysfunction suspected
how can stomach impaction be diagnosed?
ultrasound
endoscopy
surgery potentially
what can be found on physical exam with peritonitis?
fever
what are the causes of peritonitis?
diagnostic complications
surgical complications
primary gastrointestinal disorders
how can you treat peritonitis?
eliminate cause
antimicrobials
analgesia
supportive care
what indicates moderate/8-10% dehydration?
weak pulses, CRT>3s
poor jugular distention
moderately increased heart rate
what can cause increased lactate in the absence of tissue hypoxia?
increased primary lactate production
cytokine inhibition of pyruvate dehydrogenase
relative thiamine deficiency
decreased utilization/clearance of lactate by liver
what should you put PCV/TS into context with?
urine output and USG
what is normal USG in foals?
first 2 samples postpartum: 1.035-1.025
within 24 hours: <1.008
what can cause elevated creatinine?
hypovolemia/dehydration
renal disease
reduced renal clearance in premature foals
spurious hypercreatinemia
how much can you bolus?
20 ml/kg over 30-60 mins
what fluid rate is used for post-resuscitation in adults?
50-75 ml/kg/day
what are the endpoints to resuscitation?
CVP 8-12 cmH2O
blood lactate <2mmol/L
normal acid-base
urine output >0.5-1 ml/kg/hr
improvement of clinical variables
what has significant effects on GI fluid absorption?
tonicity: hypertonic slow
where can ulceration occur?
terminal esophagus
proximal/squamous stomach
distal/glandular stomach
proximal duodenum
what are the signs of ulcers in adults?
poor appetite, recurrent colic, poor BCS
change in attitude, dullness, poor performance, stiffness
asymptomatic
what blood test can you use for ulcers?
succeed equine fecal blood test
what parts of the stomach should you examine in gastroscopy?
squamous
margo plicatus
glandular
pyloric antrum
what is a grade IV for equine gastric ulcer syndrome?
extensive lesions with areas of deep ulceration
what is the mucosal protection like in the squamous and glandular portions of the stomach?
squamous: minimal intrinsic resistance to peptic injury
glandular: mucous/bicarbonate layer, prostaglandins, nitric oxide regulates mucosal blood flow
how can you treat equine gastric ulcer syndrome?
proton pump inhibitors: omeprazole
histamine type-2 receptor antagonists
antacids
protectants
what are the risk factors for stomach impactions?
excessive dry, fibrous ingesta
feeds that tend to swell after ingestion
dental disease
friesian breed
what are the clinical signs with stomach impaction?
acute and severe to chronic and mild
anorexia
uncontrollable colic unresponsive to therapy
where can you image the greater curvature of the stomach with ultrasound?
left side
9-12th ICS
what is abdominocentesis like with peritonitis?
elevated WBC
elevated protein
elevated lactate
