The Choking Horse

predispositions to choking

-bolting→ rapid ingestion

-improper chewing

-FB

-inadequate water intake

-heavy sedation and eating

-oesophageal disease and other probs

diet causing drooling/ hypersalivation

-consume legumes with fungus (rizoctonia leguminicola)

-oral PBTZ with clenbuterol

dental causes of drooling/ hypersalivation

-caries or cavities → so do full oral exam to assess this

obstructive abnormality causing drooling/ hypersalivation

-retropharyngeal lymphadenopathy

-malformation, injury, oedema

-pharyngeal disorders

-palate disorder

-guttural pouch disorder

-oesophageal problems

painful causes of drooling/ hypersalivation

-teeth issues

-trauma to mandible

-stomatitis/ glositits

temporohyoid OA

temporo mandibular osteopathy

causes of stomatitis/ glossitis

• fb most common (glossitis)

  • plant material, metal

• ulcerative stomatitis

  • phenylbutazone toxicity

  • blester beetle

• vesicular stomatitis

  • viral

• bacterial

  • actinobacillus lignieresi

complete neuro exam causes of choke

-rabies

-viral encephalitis

-veminous encephalitis and EPM

-botulism and tetanus

-meningitis

-cerebral oedema

-brainstem haemorrhage

-CNS masses

muscular causes of choke

-HYPP

-NMD

-PSSM

-masseter myositis

-hypocalcaemic tetany/eclampsia

-myotonia

-rectus capitis ventralis rupture

-white snake root toxicity

-megaoesophagus

clinical presentation of choke

-regurgitation food, water, and saliva

-ptyalism

-hysphagia

-coughing

-repeated head extensions or retching

-anxiety

Distention

Crepitus

Ptyalism

Clinical signs of complications

where see distention

left jugular furrow (right side some horses)

crepitus over the oes area?

oesophageal rupture

ptyalism

drooling

clinical signs of complications

-dehydration→ bc salva lost

-RR/abnormal pattern

-fever

-other

clinical exam for choke

-GPE

-palpate neck and thoracic inlet

-oral exam

-thoracic auscultation (aspiration pneumonia)

-NG intubation

clinical pathology findings

-hydration status (PCV/TP, urea/creatinine)

-CBC (inflam?)

-electrolytes

-acid base status

sedation for endoscopy

-xylazine

-detomidine

-topical lidocaine

how long must endoscope be to view length of oesophagus

200cm

endoscopy used to do

-irrigation and insufflation

-mucosal defects

-changes in lumen size

normal looking oesophagus on endoscope

pale pink to whute grey and longitudinal folds

contrasts for radiography

-barium (iodinated for rupture)

-double contrasts

barium as contrast admin

-barium paste PO

-liquid barium by cuffed NG tube

double contrast for radiology admin

-liquid barium by cuffed NG tube under pressure

-best definition

spontaneous resolution of choke (medical management)

-remove feed and water

-iv fluids

-NSAID or analgesic to manage fever and pain

-store without bedding

-sedation (xylazine, detom, butorph, acp)

-oxytocin for proximal obstruction

why sedate

relax oes

assisted resolution

-oesophageal lavage and drainage

-aggressive oesophageal lavage

how to oesophageal lavage and drainage

-sedate with detomidine

-head below thoracic inlet→ lets it come through nose

-repeated attempts at 8-12 hour intervals with supportive care

how to aggressive oesophageal lavage

-cuffed nasotracheal and nasosophageal tube

-decreased likelihood of aspiration

-greater mechanical advantage

-standing or under GA

if GA for assisted resolution, how is that helpful

-minimise aspiration

-aid relaxation

once obstruction relieved, how to prevent re obstruction

-repeat endoscopy to assess mucosal damage

-fusiform dilation predisposes to reobstruction

-leave without feed then small quantity soft feed 48hrs post

-give electrolytes and water

-anti inflams (nsaids)

-broad spec antibiotics

why broad spec antibiotics to prevent re obstruction

aspiration pneumonia likely if long time obstruction

surgical treatment for choke

oesophagotomy

oesophagostomy

Longitudinal Esophagotomy with primary closure

-stand with tube in place

-approach based on lesion

-incise 5cm distal to lesion

-indwelling tube

-pelleted slurry then leave to 2nd intention healing

common complication of oesophagostomy

laryngeal hemiplegia

complications of obstructions

-aspiration pneumonia

-oesophageal ulcer

-oesophageal stricture

-megaoesophagus

-diverticula

-oesophageal rupture

what is in pic

stricture

what is in pic

megaoesophagus

what is in pic

diverticula

-small pouch that protrudes from organs wall

what is in pic

oesophageal rupture