Examination of the GI tract

Question 1

What are the only reasons for not doing a rectal exam in a colic workup?

Answer 1

Patients are too small or too fractious

Question 2

What is the minimum database in a colic workup?

Answer 2

History, physical exam, rectal exam, nasogastric intubation, response to therapy

Question 3

What clues can you get from observing the horse from afar in colic cases?

Answer 3

-evidence of rolling- displaced bedding- mud on back
-quality of hay
-mentation/general behavior of horse

Question 4

Describe the head to toe physical exam for a colic workup

Answer 4

-look at everything
-auscultate bilaterally (borborygmi or abnormal sounds)
-focus on problem area (TPR-tachypnea or tachycardia or fever, MM-color and CRT, gut sounds, feces)
-assess pain level (hard to assess especially since banamine is typically on board)
-look for abdominal distension (sign of ileus- more likely surgical)

Question 5

If a patient has a fever, is it more likely a medical or a surgical problem?

Answer 5

Medical- likely infectious

Question 6

What are the two types of obstructions?

Answer 6

Functional (physiologic) or physical (mechanical)

Question 7

If you ausculate what sounds like a high pitched rainstick, what may this indicate?

Answer 7

A gas fluid interface

Question 8

How do you best assess perfusion on a physical exam?

Answer 8

-mucous membranes (moisture, refull time and color)
-extremity temperatures
-pulse quality

Question 9

What should you look for on rectal exam for colic cases?

Answer 9

-distension, displacement, abnormal structures
-be able to recognize normal and describe abnormal

Question 10

What is normal reflux in a horse?

Answer 10

Less than 2 L
->4 indicates a greater severity of disease

Question 11

What is the first thing you should do if a horse has a high heart rate and they are painful?

Answer 11

Pass a NG tube prior to any diagnostics to prevent potential stomach rupture

Question 12

In what colic condition is it common for horses to get more painful with medical treatment?

Answer 12

Severe impactions
- as you rehydrate them intestines will distend further

Question 13

What are some of the main considerations for rectal palpation?

Answer 13

Safety- horses should be sedated or have adequate restraint (stocks are good)
-Buscopan is a great drug to use for rectals- antispasmoic, anticholinergic, parasympatholytic

Question 14

What is normally felt on palpation per rectum?

Answer 14

Spleen, left kidney, small colon, pelvic flexure, cecum, female repro tract, inguinal rings

Question 15

If a horse is breaking through sedation or analgesia, what does this indicate?

Answer 15

More severe lesion- likely surgical

Question 16

Can you perform CBC/chem in the field to help with colic workups?

Answer 16

Not really- will take a long time to get results back as has to be done in clinic in most cases

Question 17

What findings can be seen on transrectal and/or transabdominal ultrasound that can help you in a colic case?

Answer 17

-SI distension
-bowel wall thickening
-motility
-abdominal fluid volume/character
-intussusceptions
-nephrosplenic entrapment
-inguinal hernia
-sand
-masses/foreign bodies

Question 18

What is the FLASH ultrasound?

Answer 18

A very fast and simple way to quickly assess colic cases
- utilize 7 fields of view
- assesses for free abdominal fluid, the appearance of the small intestine, the contents of the large intestine and the contact of the spleen with the left kidney
- first look at ventral abdomen (looking for free fluid), then left cranial abdomen (looking for stomach), then move caudal to left flank region (kidney and spleen), then right paralumbar fossa (cecum and kidney and duodenum), move craniodorsal to find right dorsal colon (looking for right dorsal colitis), then move to right ventral thorax to look at heart

*Should only take 5-10 min

Question 19

What Lab data is important to get in colic cases if possible?

Answer 19

PCV- should be 32-45%
- if high could indicate dehydration, splenic contraction or SIRS
->60 associated with poor prognosis

TP (4.6-6.9)
- elevations could mean SIRS or altered mucosal function

Lactate- should be <2
- increases could mean anaerobic metabolism (could be due to dehydration) or reduced hepatic clearance
- >6.5 associated with poor prognosis
- good to determine prognosis if surgery is pursued

Glucose
- hyperglycemia if >135, likely due to stress and potential shock
- >180 is extreme- poor prognosis

Question 20

What can the CBC tell you in colic workups?

Answer 20

WBC count:
- if elevated likely inflammatory disease
- if decreased, likely endotoxemia or leukocyte margination

Fibrinogen (>400)
- indicates inflammation

Question 21

What can the chemistry help you with in a colic workup?

Answer 21

Azotemia: evidence of dehydration, renal disease or obstruction

Liver enzymes: GGT can be elevated in colic cases
- common with large impactions near liver

Electrolyte abnormalities

Question 22

Describe the technique of abdominocentesis

Answer 22

Not commonly done in field
- perform just to the right of midline
- can do ultrasound assisted
- should use sterile prep and sterile technique
- teat cannula recommended (but can also use needle- not great if theres no obvious fluid- more risk of puncturing organ)

Question 23

What does normal fluid on abdominocentesis look like? What are some risks associated with it?

Answer 23

-clear yellow, protein <2, WBC <5000, RBCs rare

Risks: enterocentesis, bowel laceration, hemoabdomen, omental herniation

Question 24

What is a concerning number for abdominal fluid lactate?

Answer 24

> 4 (aka greater than 2X serum concentration)
- increase in PFL over time is a significant predictor of a horse with a strangulating lesion

Question 25

What are some other diagnostics you can do if still unsure about course of action in colic case?

Answer 25

Gastroscopy, fecal exam, abdominal radiography, laparoscopy, exploratory laparotomy/celiotomy

Question 26

T/F: exploratory laparotomy is commonly a diagnostic procedure

Answer 26

True- it is not always therapeutic but it can be
- dont tell owners that you will definitely be able to fix the problem

Question 27

T/F: feeling any amount of small intestine on a rectal exam is abnormal

Answer 27

True

Question 28

If pain is reduced after passing of the NG tube, what does this indicate?

Answer 28

The problem is likely medical- due to ileus
- if still painful after, likely a worse problem

Question 29

What does tapping serosanguinous fluid tell you?

Answer 29

There is compromised/necrotic bowel somewhere