GIT Flashcards
expected elevated pulse of a colicky foal <1month old
80-100bpm
expected elevated pulse of a colicky foal < 2month old
70bpm
expected elevated pulse of a colicky foal < 3month old
60bpm
why is PCV/TP not as reliable in foals as adults?
foals always have quite a low protein, but still okay indicator of hydration
what does lactate concentration indicate?
perfusion
is peritoneal fluid analysis routinely performed in foals?
no - dt increased complication rates vs. adults
what is US useful for when investigating a colicking foal?
GIT: intestinal motility, intestinal wall thickness, stomach size, peritoneal fluid
Umbilical structures
DDx for obstructive causes of colic in foals
- Non-strangulating:
- meconium impaction
- LI impaction
- intussusception - Strangulating
- intestinal volvulus
- herniation
DDx for congenital causes of colic in foals
- intestinal atresia
- ileocolonic aganlionosis
ddx for misc. causes of colic in goals
- gastroduodenal ulceration
- peritonitis
- uroperitonuem
- umbilica/abdominal abscess
- enterocolitis
what is normal foal USG
1.005-1.010
when should passage of meconium be completed by?
48hrs
lab data indicative of IVFT in foals
USG >1.020
Lactate >2mmol/L
analgesia options in colicky foal
- NSAIDs (if hydrated): flunixin, meloxiam, ketoprofen
- Opioids: butorphanol (can cause profound sedation)
- Alpha-2 agonists: xylazine (in older foals)
initial tx of meconium impaction
- warm soapy water
- foal standing/lateral
- lubricate soft tubing (Foley cath)
- 50-100mls for a 50kg foal - administered by gravity flow
- can rpt several times (beware rectal irritation)
MOA of retention enema using acetylcysteine
4% acetylcysteine
MOA: cleaves disulphide bonds and decreases the viscosity of meconium
- keep in place for 30-45mins
non-infectious causes of foal diarrhoea
- foal heat (assoc. w/ change in gut flora/copraphagy and starting to eat mare’s feed)
- nutritional (ie. large quantities of milk w/ premies)
- systemic dz (ie. dummy foals w/ impaired GIT perfusion)
DDx nutritional causes of foal diarrhoea
- commonly in foals not able to handle large quantities of milk ie. premature/sick foals
- milk replacers
- lactose intolerance
- perinatal asphyxia-assoc. D+
- sand ingestion - typically older foals
parasitic causes of foal D+
- Nematodes
- strongyloides westeri
- parascaris equorum
- small/large strongyles - Cryptosporidium
viral causes of foal D+
- rotavirus (most common)
- coronavirus
- adenovirus
pathogen of rotavirus in foal D+
- High contagious - transmitted by faecal-oral route
- Short incubation period 18-24hs
- Dz severity determined by: immune status, inoculation dose, age
- Small intestine only - denudes SI microvilli: brush border enzyme deficiency leading to inadequate digestion and osmotic D+ in the colon, compensatory crypt cell proliferation (increased secretion), production of an enterotoxin
- Age-related colonic compensation: worse if <30d
dx of rotavirus
faecal antigen tests
tx of rotavirus in foals
- supportive: IV and enteral fluids
- bismuth subsalicylate
- ABs not indicated unless foal <2wks
explain protocol for maternal vaccination to prevent rotavirus
1st preg vaccinate in gestational months 8,9 and 10
thereafter booster during last month of preg
w/ DuvaxynR
list bacterial causes of foal D+
- Cl.perfringens biotype A and C
- Cl.difficile
- Salmonella
- Bacteroides fragilis
- Rhodococcus equi
- Lawsonia intracellularis
- E.coli (rare)
compare CS of C.perfringens biotype C and A in foals
- biotype C: haemorrhagic D+, abdo distension, colic, circulatory shock, high mortality
- biotype A: signs more variable, variable mortality, include transient bloody stool, colic and fever
Diagnosis of clostridial D+ in foals
- Enterotoxin in C.perfringens
- Toxin A/B C.difficile
- PCR
- Culture
tx of clostridial D+ in foals
- Supportive
- crystalloids + colloids
- blood gas –> acid/base + lytes
- anti-inflam/analgesia
- nutrition - enteral/parenteral - ABs: metronidazole +/- penicillin
- Biosponge
clinicopath findings assoc. w/ salmonella D+
- initial degenerative neutropaenia and evidence of toxicity
- rebound neutrophilia
- elevated fibrinogen
- severe hypoproteinaemia
- lyte disturbances
diagnosis of salmonella in foals
- Blood culture: foals <1mo freq. bacteraemic
- Faecal culture: five samples spread out
- Faecal PCR
ABs to tx. salmonella D+
gentamicin, fluoroquinolones
when is parenteral nutrition required in foals?
if milk with-held for
>6hr in neonates
>24hrs in older foals
when is “GIT rest” indicated in foals?
rest for 12-24hrs if
colic, abdo distention, haemorrhagic D+, rotaviral or clostridial infection
describe parenteral nutrition protocol in colicky foal
Dextrose 4-8mg/kg/min IV for up to 48hrs
components of parenteral fluid plan in foal w/ D+
Deficit (% dehydrated x BW) to correct over 6hrs
Ongoing losses + maintenance = the rest
3 electrolyte abnormalities assoc. w/ foal D+
- hyponatraemia
- hypokalaemia
- hypochloraemia
what blood gas parameters indicated tx. for metabolic acidosis
low CO2 + low bicarb
pH <7.25 and base deficit >10mEq
how do you calculate bicarb deficit?
Deficit = Base deficit (mEq/L) X BW (kg) x 0.5 (bicarb space)
–> replace half rapidly, then over 6hrs
indications for colloids IVFT in foals
- severe hypovol shock
- hypoproteinaemia
- FPT
common CS of endotoxaemia in adults
- fever
- tachypnoea, tachycardia
- dark MM
- toxic gingival line
- increased CRT
less common CS of endotox in adults
- D+
- haemorrhage
- colic
- ileus
- fasciculations
sequelae of edotoxaemia in adults
- DIC
- laminitis
- renal failure
criteria for isolation of adult horses
D+
+ fever OR leukopaenia
ddx infectious causes of adult D+
- salmonella
- clostridium difficile/perfringens
- Coronavirus
- Larval cyathostomiasis
- Exotic: Neorickettsia risticii
ddx non-infectious causes of adult D+
- dietary
- AB induced
- heavy metals (arsenic)
- cantharidin (blister beetle –> leads to hypoCa)
- NSAIDs
- CHO-overload
- intestinal anaphylaxis
- acorns
lab findings assoc. w/ adult D+
- Acidaemia: bicarb loss in D+, lactic acidosis
- Lytes; Hypo Na, Cl, K (loss), hypoCa (incr. loss of protein-bound calcium, decreased intake)
- Hypoproteinaemia (hypoalbumin)
- Neutropaenia w/ toxicity and left shift
- Inc. PCV/Lactate
- Eleavted liver enzymes + pre-renal azotaemia
salmonella risk factors in adult D+
- transportation
- dietary change
- recent ABs
- recent sx
- other GIT dz
- wet, dark conditions
- common use of nasogastric tubes
describe dx of salmonella through faecal cultures
- five faecal cultures/samples no closer than 12 hours apart
- not sensitive dt intermittent shedding + dilution of bacteria in D+
risk factors for clostridial D+
- neonates
- hospitalisation
- AB use
tx of larval cyathostomiasis in adults
- larvicidal doses of fenbendazole
- moxidectin
what can cause sudden emergence of hypobiotic larvae to cause larval cyathostomiasis D+ in adults?
- stress: sx, hot weather, handling
NSAID tox is associated with?
Right dorsal colitis
tx of Right dorsal colitis
- Reduce work of gut via diet mod
- Metronidazole
- PGs
- Corn oil
- Sucralfate
- Low dose psyllium
- AVOID NSAIDSSSS
arms of colitis management
- IVFT and lytes
- Preservation of colloid oncotic pressure
- Suppression of inflam
- Mucosal repair
- Maintain adequate calorific intake
- Minimise complications
- Nursing/supportive
maintenance fluids for adult/day vs neonate/day
adult = 60ml/kg/day neonate = 100ml/kg/day
initial fluid rates in L/hr for dehydration
- mild
- mod
- severe
mild 2-5L/hr
mod 5-10L/hr
severe >10L/hr
fluid deficit correction timeframe
half over 3-6hrs, rest over 24hs
parameters useful to assess IVFT
- HR
- mentation
- Urine production
- PCV/Ts
- Lactate
indicated fluid choice if horse in circulatory shock + hypoproteinaemic
- synthetic products at 10ml/kg (penta/hetastarch)
- plasma 2-8L
list 4 anti-endotoxic drugs to manage inflm
1 NSAIDs - flunixin
- Pentoxyfylline
- Polymyxin B
- Plasma
tx neorickettsia w/ what ABs?
tetracyclines
tx clostridial diseases w/ what ABs?
metronidazoles
ABs indicated w/
- severe neutropaenia
- immunocomp (foals)
- bacterial causes
actions of biosponge
absorbs clostridial and endotoxins
management of laminitis/DIC in colitis cases
- ice feet
- dalteparin
- plasma
ddx inflammatory causes of chronic D+
- chronic salmonellosis
- parasitism
- granulomatous enteritis/colitis
- neoplasia
- sand
- mycobacteria
- NSAID tx
- intra-abdominal abscessation
ddx non-inflammatory causes of chronic D+
- dysbiosis: NSAIDs, ABs, dietary stress
arms of management of chronic D+
- Diet: fibre, grass, lytes water
- ABs/Anti-protozoala: metronidazole
- Transfaunation
+/- corticosteroids?
causes of duodenitis/proximal jejunitis
- clostridium difficile
- salmonella
- mycotoxins
+/- feeding practices?
characteristics of duodenitis/prox. jejunitis
- non-strangulating functional obstruction
typical findings (Ps) of duodenitis/proximal jejunitis
- Pain: mod to severe, progressive, relieved by gastric decompression
- Paunch: minimal to none
- Pulse: usu HR >80, reduced by gastric decompression
- Perfusion: dry, dark mm, > CRT
- Peristalsis: absent
- Percussion: none
- Pass a tube: large volume reflux +/- blood tinged
- Palpation: dilated, compressible SI
9 .PCV/TS/Lactate: all increased, responds to IVFT - Peritoneal fluid: elevated WBS and TS, but not RBCs
- Pictures: US - dilated, thick walled SI
ABs for duodenitis
penicillin (IM)
metronidazole (per rectum)
– targets clostridials + some gram -ves
ddx causes for septic peritonitis
- urine
- bile
- lymph/chyle
- neoplastic
- FB
pathogen assoc. w/ primary peritonitis
Actinobacillus equuli
peritoneal fluid characteristics w/ septic peritonitis
Increased: WBCs, protein, lactate, % neuts
Decreased: pH, glucose
tx of primary peritonitis
- ABs: pen, tetracyclines
2. NSAIDs
tx. of secondary peritonitis
- ABs: broad spec inc. anaerobes
- NSAIDs
- Tx underlying dz + endotozaemia
- Prevent complications
- Abdominal lavage and drainage
px of primary vs. secondary peritonitis
- Primary = good
2. Secondary = guarded
ddx for inflammatory bowel diseases
- malabsorptive, infiltrative dz
- idiopathic IBD
- MEED
- lymphosarcoma
- proliferative enteropathy
- mycobacterium
typical IBD presentation
- young, STBs
- weight loss w/ good appetite
- oedema dt hypoprotein.
+/- D+
3 types of IBD
- Granulomatous
- Lymphocytic- plasmacytic
- Eosinophilic
IBD investigation/tests
- CBC: mild anaemia
- Biochem; hypoalbuminaemia
- UA: rule out PL-nephropathy
- Document malabsorption: glucose/xylose absorption test
- Biopsies
management and px of IBD
- corticosteroids +/- other immunosuppresants
- sx if focal dz
- difficult management - poor px
what does MEED stand for?
multisystemic eosinophilic epitheliotropic disease
eosinophilic syndrome effects the GIT and….
the skin
tx and px for eosinophilic syndrome
- Immunosuppresive tx
2. Poor px
compare lymphoma type px
- Poor px in alimentary, mediastinal, multicentric
2. Good in cutaneous
causative agent of proliferative enteropathy in weanlings
Lawsonia intracellularis
tx and px of proliferative enteropathy
- Tetracyclines
2. Fair prognosis - may have growth restriction
pathogen of proliferative enteropathy
epithelial proliferation dt L.intracellularis –> thick wall SI –> malabsorption –> hypoalbuminaemia
+/- colic, fever, D+
dx of proliferative enteropathy
serology and faecal PCR
ddx for weight loss
- Decreased energy intake: limited access to feed/inappropriate feed, dysphagia, malabsorption/digestion, anorexia
- Increased energy requirements: physiologic, cachexia, sepsis/surgical/dz stress, ageing
top 3 causes of weight loss
- Dietary problems
- Dental disease
- Parasite burdens
CS of colic assoc. pain
recumbency, stretching, bruxism, Flehmen response, arching of neck, flank watching or biting, pawing, kicking at belly, rolling, posturing to lay down, sweating, posturing to urinate
considerations when assessing pain
- duration
- severity: response to analgesics
- persistance
- visceral or parietal
appropriate analgesic protocols to manage colic pain + facilitate exam
- Xylazine 0.4-0.6mg/kg IV
- Detomidine 0.01-0.02mg/kg +/- opioid
- Flunixin 1.1mg/kg
paunch locations + indications
- Dorsal: large colon/caecum
- Ventral: fluid - ascites/rupture/haemoperitoneum
- SI; only in neonates
- Cranioventral L - stomach
- Abdominal distention –> large intestinal
expected pulse with strangulating colic
> 80
ddx increased peristalsis
- spasmodic
- impending colitis
- early obstruction
ddx reduced peristalsis
anything that reduce GI function
- colics, sedatives, prolonged fasting
dorsal pings indicate
large intestinal obstruction
large volume reflux is assoc. w/
gastric or SI obstruction/lesion
what net reflex V is normal?
<2L
drugs to safely facilitate rectal palpation
- sedation
- intrarecal lidocaine
- IV scopolamine (muscarinic antagonist)
- IV buscopan - relax rectum but gets tachycardic
PCV/TS dissociation is a..
poor prognostic indicator
size needle to collect peritoneal fluid
18G
normal peritoneal fluid lactate
<2mmol/L
peritoneal lactate level indicative of strangulating lesion
> 6mmol/L
areas to assess via US
- Stomach: full of fluid –> pass a tube
- Small intestine - dilated/immotile?
- Left kidney/spleen - left dorsal displacement?
- Colon
- Chest - check for fluid build up
Ddx. small intestinal non-strangulating obstructions
- impactions
- intussusceptions
- idiopathic focal eosinophilic enteritis
tx of ileal impactions
- Analgesia; good response
- Gastric decompression: rpts
- NPO-IVFT
- Sx
ascarids assoc. w/ ileal impactions of weanlings
Parascaris equorum
presentation of ascarid assoc. ileal impactions
weanlings
- assoc. w/ deworming –> obstruction+/- rupture
ddx. large intestine non-strangulating obstructions
- impactions: caecal, colonic (sand)
- Displacements: RD/LD DLC, Pelvic flexure retroflexion, non-strang. volvulus
- Intussusceptions
- Enterolithiasis
what tape worm is assoc. w/ caecal intussusceptions?
Anoplocephela perfoliata (tx. w/ praziquantel)
CS of caecal impactions
- reduced faecal output + appetite
- reduced ileocaecal flush
sequelae of caecal impactions
propensity to spontaneously rupture
compare cause and prognosis for primary vs. secondary caecal impactions
- Primary: hard/ingesta filled –> fair px
2. Secondary: fluid-filled, assoc. post-GA, pain –> guarded px
when is sx intervention for caecal impactions indicated?
- 8-12hs after signs dt rupture risk
risk factors for large colon impaction
sand, parasites, dental disease, decreased water intake, inadequate exercise, poor quality fibre, recent changes in feed, recent changes in stabling
common sites of large colon impaction
pelvic flexure > dorsal colon
medical tx for large colon impactions
- Analgesia: xylazine to examine vs flunixin to tx
- Light exercise: hand walking
- W/hold feed
- Intestinal lube: mineral oil/osmotic agents (magnesium sulphate), sodium sulphate
- IVFT/enteral isotonic salt solution
psyllium tx protocol for sand enteropathy
- Psyllium 1g/kg daily by NGT for 3-14d in oil
2. Add MgSO4 for 4 days
signalment for enterolithiasis
arabians > 5yo
- intestinal calculi: magnesium ammonium struvite –> forms around nidus over years
- diet high in Mg and protein + alkaline –> lucerne/QLD
describe US supportive of LDDLC
skin –> spleen –> colon (no kidney)
action of LDDLC
left colon rotates on axis and moves dorsally to spleen
–> can become trapped in nephrosplenic space
risk for LDDLC
- crib biting
- changes in feed
conservative management of LDDLC
- conservative: fast + IVFT + analgesia
- shrink spleeN: phenylephrine, exercise
- rolling under GA…
US findings supportive of RDDLC
mesenteric vessels against body wall
what % of RDDLCs need sx intervention?
> 50%
what degree of torsion usu results in a non-strangulating volvulus and vasculature not compromised?
<180 degrees
ddx. small intestinal strangulating obstructions
- volvulus
- mesenteric rents (inc. gastrosplenic lig)
- epiploic foramen entrapment
- pendunculated lipoma
- mesodiverticular bands
- hernias
tx options for strangulating small intestinal obstructions
- sx or euthanasia
periparturient broodmares have a higher risk of…..
large intestinal volvulus
ddx for recurrent colic
- spasmodic
- lymphoma
- obstructions: ileal, colonic
- adhesions
- intussusceptions
- EGUS
- gastric impaction
- enterolithiasis
- inflam dz
- idiopathic
- others
define chronic colic
persistent colic > 3days (w/out analgesia)
ddx chronic colic
- colon impaction
- peritonitis
- enterocolitis
- colonic displacement
predisposing factors to choke
- poor dentition
- dry feed
- dehydration
- sedation
- bullying
- rapid/glutinous feeding behaviour
CS of choke
- head/neck extension
- retching
- ptyalism
- feed/saliva at nares
areas of narrowing assoc. w/ choke
- Caudal to larynx
- Thoracic inlet
- Heart base
- Diaphragmatic hiatus
management of choke
- Sedation
- Gentle lavage and pressure w/ head down
- Motility mod drugs: oxytocin (relaxes smooth muscle in oesophagus)
–> if unsuccessful: IVFT for 12-24hrs –> anaesthesia w/ cuffed nasogastric/ETT –> sx last resort
complications of choke
- Aspiration pneumonia
- Repeat choke
- Stricture/rupture
causes of recurrent choke
- strictures
- oesophageal dysmotility
- other mechanical problems: diverticula, cyst, tumour, abscess
neonatal cardiac gland disease CS
well foals –> sudden death
pathogenesis of gastroduodenal ulcer disease in weanlings/late suckling foals
initally diffuse duodenitis –> delayed gastric emptying –> acid erosion and reflux –> pyloric stenosis –> acute colic
CS of gastroduodenal ulcer disease in weanlings/late suckling foals
early/missed signs: lethargy, D+, mild colic, reduced feed intake
later: post-prandial colic, ptyliasm, bruxism, posturing, lying on back
management of gastroduodenal ulcer disease in weanlings/late suckling foals
- PPI
- Sucralfate
- Bethanechol
- Nutrition/fluids
- Analgesia (not NSAIDs…)
risk factors assoc, w/ squamous disease
- high conc. feeds/ meal eating
- low forage
- isolation
- time in training
- crib biting/radio listening
risk factors assoc, w/ glandular disease
- WBs
- exercise >4d/wk
- multiple handlers/riders
squamous disease pathophys
inc. histamine + gastrin + acetylcholine + PGs to stim H+ secretion –> splash onto non-glandular epithelium
dx of EGUS
gastroscopy only definitive way to diagnose EGUS
squamous disease grades
1 - hyperkeratosis
2 - single, small ulcer
3- large, extensive, single ulcer
4 - extensive, deep, coalescing
glandular disease classification
- Severity
- Location
- Dist: focal/multifocal/diffuse
- Descriptors: flat/ raised/ depressed + erythematous/fibrinonecrotis/haemorrhagic
timing of omeprazole admin
- 8hours fasted - 30-60mins before feeding –> high plasma conc. when proton pump activation w/ feed
what breed of horse is predisposed to gastric rupture?
TBs
most common gastric neoplasia of geriatric horses
SCC
CS for chronic liver dz
- anorexia, decreased appetite, weight loss, lethargy
- change in demeanour
- photosensitive dermatitis
early signs of HE
yawning, aimless wandering, mild ataxia, decreased awareness
later signs of HE
head pressing, somnolence, aggressive, recumbency
clin path indicative of liver dz
- GGT and ALP –> biliary epithelium (inducible)
- Bilirubin indicative of liver function - not sensitive or specific - anorexia can increased 2-3x
- Hepatocellular enzymes: SDH, GLDH, AST
- Serum bile acids –> indicative of liver function
cause of HE
high levels of CSF ammonia in brain -> accum glutamine –> cytotoxic + oedema
ddx chronic liver dz
- pyrrolizidine alkaloid toxicosis
- neoplasia
- liver abscess
- chronic active hepatitis
- cholelithiasis
location to perform a liver biopsy
12-15ICS btwn lines formed from tubercoxae to shoulder + elbow
plants that cause pyrrolizidine alk tox
- paterson’s curse (Echium plantagineum)
- common heliotrope
- rattlepod (crotalaria sp)
- ragwort
- cotton fireweed (senecio spp.)
biopsy characteristics of pyrrolizidine alk. tox
- megalocytosis
- biliary hyperplasia
- periportal fibrosis
dietary modifications to manage chronic liver diz
- Limit protein
- Maintaine adequate calories
- Grass hay (not lucerne)
- Sorghum/cracked corn/beet pulp: high ratio of BCAAs: AAs
difference w/ tx of equine HE and small animals
in equine you do NOT use antimicrobial to decrease ammonia producing flora as you do with dogs/cats
- in horses still use lactulose (+ mineral oil) to decreased GI absorption of digested protein
ddx for acute liver disease
- Theilers
- Cholangiohepatitis (*E.coli)
- Bacterial: Clostridium piliformis (tyzzers), Cl.novyi B (Blacks dz)
- Viral: EIA, EVA, EVH-1 (neonates)
- Toxic: blue/green algae, mycotoxins
- Acute biliary obstruction: chronic right dorsal displacement vs. cholelithiasis
signalment of theilers dz
- often 4-10wks post tetanus antitoxin - assoc. w/ Flaviviridae
- summer, autumn
- > 2yo
- broodmares 1-3mth post foaling
Mortality % of theilers
90 - rapid hepatic failure over 2-7d
compare primary and secondary cholangiohepatitis causes
- Primary: ascending bacterial infection from SI (E.coli)
2. Secondary: sequelae to cholelithiasis, chronic active hepatitis, hepatic neoplasia
