LA Vomiting and Regurgitation Flashcards
describe vomiting in large animals
- pathophysiology:
-chemoreceptor trigger zone stimulation
-visceral afferent stimulation - clinical signs:
-before: inappetence (nausea), increased salivation, retching - horses:
-poorly developed reflex
-high pressure esophagus/high tone lower esophageal sphincter
describe vomiting in ruminants/camelids
toxicities:
1. causes:
-cardiac glycosides!!!!!: azalea, rhododendron, mountain laurel, foxglove, oleander
-some organophosphates
-sneezeweed
- diagnosis:
-history of exposure
-other clinical signs of toxicity
intestinal causes: more RARE
1. causes:
-diaphragmatic hernia of reticulum
-actinobacillus rumenoreticulitis
-around ororumen tube when have GI disease
describe pathophysiology of regurgitation
3 origins
- esophagus:
-mechanical obstruction
-functional obstruction: hypomotility - reticuloruminal:
-normal in cows (some is normal)
-increased:
–outflow obstruction; relatively uncommon - gastric:
-foals: gastric outflow/duodenal obstruction
describe clinical signs of regurgitation
- frothy saliva and food
- from nose:
-horse and camelid
-soft palate conformation
-bilateral discharge - from mouth and/or nose:
-ruminants
describe differentials for regurgitation
- dysphagia!!! need to rule out!!
-pain in oral cavity and pharynx
-obstruction in pharynx, larynx
-neurological dysfunction of pharynx (central or peripheral); guttural pouch!! - other causes of nasal discharge
-URT
-LRT
ANY NEURO SIGNS CAN BE RABIES; GLOVES BEFORE STICKING HANDS IN MOUTH
describe esophageal obstruction (4)
- primary:
-intraluminal
-food or other foreign material: bedding, stones, wood, etc. - secondary:
-intra or extra luminal
-masses: neoplasia or abscess, intraluminal or extraluminal mediastrinal/cervical
-other: structure, diverticulum, cysts, vascular ring abnormalities - common in horses and cows
- uncommon in camelids and small ruminants
describe physical exam for esophageal obstruction?
- clinical signs:
-horses: anxious, neck extended, gagging, retching (esp proximal), coughing, odynophagia (painful swallowing), ptyalism, sweating
-cow: anxious, ptyalorrhea (hypersalivation), swinging head (violent), staggering
- external palpation
- secondary problems:
-dehydration
-bloat
-aspiration pneumonia - NGT/NRT/ORT:
-inability to pass is diagnostic for obstruction
-can get an idea on where based on where tube stops
-does NOT give info on what obstruction is unless get some out
describe clin path for esophageal obstruction
related to saliva loss and what not able to get through food/water
horses:
1. especially for when >24hr
2. dehydration
3. saliva is high in bicarb, Cl, Na, and K: acidosis initially then alkalosis due to hypochloremia, hypoNa, hypoK (also not getting from food)
cows:
1. esp when longstanding
2. dehydration
3. saliva high in bicarb, Na, later K so acidosis, hypoNa, hypoK
describe ultrasound for esophageal obstruction
- esophagus:
-cervical: can tell where, extent, wall thickness and integrity - thorax:
-aspiration pneumonia
-mediastinal leakage potentially can detect
describe radiographs for esophageal obstruction
- plain:
-cervical or thoracic
-FB, periesophageal gas - contrast:
-positive: diameter
-double contrast: mucosal detail
-false positives swallow, sedation, recent NGT, repeatable=defect more likely instead of just due to contrast
describe endoscopy for esophageal obstruction
- definitive dx!
- visualize:
-obstruction: material, size
-mucosa - insufflation for diameter: can be difficult to interpret
describe choke locations
at areas of narrowing
- cervical:
cows: cranial cervical especially - thoracic inlet
- base of heart
- nearing cardia: horse
describe choke in horses
- obstructing material:
-usually roughage: hay, alfalfa cubes, dry beet pulp
-FB less common: apple, carrot, wood, stone - history/risk factors:
-dentition: poor mastication
-prior esophageal trauma
-wolfing/gulping/food competition
-feed changes
-sedation
-dehydration - treatment: resolve obstruction
-sedation, anxiolysis: head down
-muscle relaxation: oxytocin, buscopan, intraluminal lidocaine
-lavage: standing, gen anesth, cuffed tube
-supportive care, time, repeat: most common!
-surgery: rarely done, complicated!
- slow refeeding with soft food initially
describe complications of choke in horses
- increase with duration so resolve ASAP
- aspiration pneumonia
- ulceration:
-circumferential = increased risk of stricture - esophagitis
- dilation proximal to site
- rupture
describe recurrence, prognosis, and prevention of choke in horses
recurrence: up to 37%
-highest in the first 24-48 hours
prognosis:
-survival 78% = good
-potential for chronic/recurrent choke: dietary modifications
prevention:
-dental care
-diet modification/avoidance
-feed alone, large rocks in feed tub to slow down
describe choke in cows
- obstructing material
-often large chunks: apple, potato, beet tops, corn cob - secondary bloat:
-can be acute, severe with complete obstructions: life threatening; need trocharization
-or slowly develop with incomplete obstructions
describe treatment of choke in cows; include aftercare, complications, and prognosis
- sedation: head low like for horses
- retrieve through mouth
-massage retrograde
-hand
-corkscrew/pincher attachment probang
-REMEMBER RABIES IS A DDX SO CAREFUL WITH HANDS IN MOUTH - ORT/NGT and time if feed material as for horse (temporary rumen fistula)
- rumenotomy and snare, lavage
aftercare:
1. soft diet, feeding through tube or rumen fistula to allow esophagus to heal
-complications similar to horse
-prognosis: good for longterm unless mucosal damaga
describe stricture pathogenesis, treatment, and prognosis
- most often secondary to circumferential mucosal damage after choke
-30d maximal reduction/minimum diameter
-remodeling to 60 days, don’t rush to more aggressive treatment before 60d - can also be caused by corrosive meds, trauma, congenital
- treatment:
-bougenage: metal balloon to dilate; takes many tries and horses hate (shocker)
-surgery: high rate of complications and recurrence of stricture - prognosis:
-5/7 resolve by 60d
-give it time, diet mod longterm
describe esophageal diverticulum
uncommon in LA
2 kinds
- traction:
-wound (spontaneous or surgical) with subsequent contraction of periesophageal tissue causes tenting
-usually asymptomatic, described treatment for stricture - pulsion:
-mucosa protrudes through muscular defect
-if fill with feed can obstruct lumen
-can resect or invert (if small)
describe pathogenesis, clinical signs, and treatment of esophageal rupture
pathogenesis:
1. longstanding choke
2. FB, NGT penetration
3. external trauma
4. extension of infection
clinical signs:
1. depend on location
2. cervical: swelling, emphysema, drainage, URT obstruction
3. thoracic/abdominal: mediastinal/pleural/abdominal sepsis, colic, FUO
treatment:
1. drain and lavage
2. feeding tube
3. long and complicated treatment with not super great prognosis
describe hypomotility
- acquired:
-cattle: pharyngeal trauma: vagal disturbance, hiatal hernia
-horses: proximal dilation post-choke, esophagitis in foals with gastric/duodenal obstruction, extraluminal obstructions
- congenital/idiopathic in young horses
- neurologic/neuromuscular, muscular:
-cattle: rabies, botulism, tetanus (may mimic signs or cause dysfunction)
-horses: pleuropneumonia: causes vagal disruption, EPM, EHV myelitis, dysautonomia, botulism
describe diagnosis and treatment of hypomotility
diagnosis:
1. transit study
2. endoscopy
3. neuro exam
treatment:
1. underlying cause
2. dietary modification
3. feed from height
describe esophagitis pathogenesis
- reflux esophagitis most common!
-exposure to acid (worse with bile salts) - gastric ulcer disease, motility disorder, gastric outflow obstruction, lower esophageal sphincter dysfunction
- other: trauma (NG tube, choke), infection, chemical injury (medications, cantharidin)
describe clinical signs and treatment of esophagitis
clinical signs:
1. overlap with gastric ulcer disease and esophageal obstruction
2. hypersalivation and bruxism signs of esophageal pain
treatment:
1. underlying disease
2. acid reduction, prokinetics
describe reticuloruminal disease-ruminal indigestion
- group of diseases associated with dysfunction of reticulorumen
- digestion in forestomach reliant on microbial fermentation
-requires coordinated eructation, mixing, rumination, remastication, and emptying aborally
-requires appropriate microbial composition, feed, water, buffering, temperature, electrolyte, and VFA exchange
-functions are highly inter-related: abnormalities of any component can cause indigestion
describe classification of ruminant indigestion
adult:
-primary: motor dysfunction, fermentation dysfunction
-secondary
young:
-disturbances in developmental mechanisms
describe primary ruminant indigestion
motor disorders and ruminal wall disease ddx
- traumatic reticuloperitonitis
- bloat: free gas or frothy
- vagal indigestions: failure of omasal transport
- reticulitis, rumenitis, paraleratosis
- obstruction of cardia, reticuloomasal orifice
- diaphragmatic hernia
