Gastrointestinal Disease of the Horse Part I

Question 1

what are the primary obstructions that cause choke?

Answer 1

foreign bodies
usually roughage
pelleted feed

Question 2

what are the risk factors for choke?

Answer 2

prior esophageal trauma
poor dentition
wolfing or gulping food

Question 3

when should you give antimicrobials in choke?

Answer 3

if risk for aspiration pneumonia is higher: longer duration or more proximal

Question 4

what is buscopan?

Answer 4

anticholinergic spasmolytic agent (smooth muscle relaxant)

Question 5

what is the breakdown of muscle in the esophagus?

Answer 5

cranial 2/3 is skeletal muscle
caudal 1/3 is smooth muscle

Question 6

what can a double contrast esophageal study help with?

Answer 6

esophageal wall abnormalities or ulcerations

Question 7

what are the sequela of esophageal choke?

Answer 7

esophageal erosions
esophageal rupture
aspiration pneumonia
esophageal stricture
esophageal diverticula
megaesophagus

Question 8

how can recurrent choke be prevented?

Answer 8

routine dental management
feed management

Question 9

why should you look at the mucous membranes and CRT of a horse with colic?

Answer 9

determine degree of cardiovascular collapse

Question 10

what should you normally palpate in a rectal examination?

Answer 10

pelvis
bladder
uterus if female
inguinal rings
spleen
caudal left kidney
aorta
iliac arteries
ligament of cecum

Question 11

how many bands does the cecum have?

Answer 11

4
palpate ventral band

Question 12

where should you perform abdominocentesis?

Answer 12

right of midline at most dependent part of ventral abdomen
hand width caudal to xiphoid, hand width lateral to midline

Question 13

what color should abdominocentesis be?

Answer 13

clear yellow

Question 14

what should thee ratio of abdominal lactate to serum lactate be?

Answer 14

<2

Question 15

what is anterior enteritis also called?

Answer 15

duodenitis/proximal jejunitis

Question 16

how is metoclopramide a prokinetic?

Answer 16

enhances release of acetylcholine

Question 17

what does erythromycin do?

Answer 17

works on motilin receptors
enhances gastric emptying in normal horses

Question 18

what are the causes of secondary impactions?

Answer 18

intramural obstructions: tumors, strictures, diverticula, cysts
mediastinal masses: may cause extramural obstructions

Question 19

what are the risk factors for choke?

Answer 19

prior esophageal trauma
poor dentition: main
wolfing or gulping of food

Question 20

for what patients can you use cuffed naso-tracheal intubation?

Answer 20

smaller patients: limitations in length of ET tube

Question 21

what can cause secondary impactions?

Answer 21

intramural obstructions
mediastinal masses may cause extramural

Question 22

what is buscopan/butylscopolammonium?

Answer 22

anticholinergic spasmolytic agent: smooth muscle

Question 23

what is oxytocin/peptide hypothalamic hormone?

Answer 23

smooth muscle relaxant at high doses
neuromodulator of centrally mediated proximal esophageal motility?

Question 24

what are the effects of detomidinee/xylazine?

Answer 24

inhibitory effects on proximal esophageal motility in vivo
no effect skeletal muscle
pain/anxiety relief, decreased spontaneous swallows

Question 25

how can you manage feed for prevention of recurrent choke?

Answer 25

avoid competition
use wet feeds in horses that do not chew well
feed smaller quantities frequently
ensure water access
complete feeds for horses with strictures

Question 26

what should you look for in signalment and history?

Answer 26

age and breed
duration of signs
fecal output
observed degree of pain
prior administration of analgesia

Question 27

which gastrointestinal organs can you palpate on rectal examination in which you can feel no bands?

Answer 27

small intestine
pelvic flexure: has one but not palpable

Question 28

which gastrointestinal organs have 4 bands?

Answer 28

cecum: palpate ventral band
right ventral colon: cannot reach
left ventral colon

Question 29

how many bands does the dorsal colon have?

Answer 29

left dorsal: 1
right dorsal: 3, cannot reach

Question 30

what are the common abnormal findings in horses with colic?

Answer 30

abnormal amount free fluid
dilation of the stomach
visualization of left kidney
duodenum
other small intestine abnormalities
colon abnormalities
presence free thoracic fluid

Question 31

what values in abdominocentesis are normal?

Answer 31

clear yellow
WBC <5,000/ul
total protein <2g/L
ratio of abdominal lactate to serum lactate <2

Question 32

what are the clinical signs of anterior enteritis?

Answer 32

moderate to severe abdominal pain- gastric distension
moderate to severe gastric reflux
dehydration: tachycardia, prolonged CRT
may be associated with fever

Question 33

how can you treat anterior enteritis?

Answer 33

gastric decompression- every 2 hours
NPO
antibiotics?
manage endotoxemia
motility stimulants
intravenous fluids

Question 34

what are the effects of lidocaine?

Answer 34

may suppress primary afferent neurons
anti-inflammatory properties
direct stimulatory properties on smooth muscle

Question 35

where might the primary sites of action for erythromycin be in horses?

Answer 35

cecum
large colon

Question 36

how does neostigmine work?

Answer 36

increases receptor levels of acetylcholine by inhibiting enzyme acetylcholine esterase

Question 37

what does bethanecol/acetylcholine receptor agonist do?

Answer 37

works throughout GI tract
improves gastric emptying
enhances cecal emptying