Horse Colic - Diagnosis Flashcards
What is the annual % of horses developing colic?
10%
What % of horses with colic respond to medical therapy after 1-2 treatments?
75% and 89% respectively
What % of horses with colic require referral/surgery?
Anywhere from 2-10%
What is “simple colic”? What proportion of colics fall into this category?
Simple distension - spasmodic or gas colic
Majority of colics seen in practice fall into this category
What is the clinical presentation of “simple colic” ie. spasmodic and gas colic - give brief causes, clinical signs, treatment
Spasmodic - gut spasms, not sure what causes it, respond well to 1-2 doses of analgesics
Gas colic - flatulence, too much rich grass, no other clinical signs
What are the 2 causes of simple obstruction in the horse?
Intraluminal obstruction
Non-strangulating displacements or entrapments
Define simple obstruction
Mechanical obstruction of SI or LI that results in obstruction of food or gas moving through gut
Results in distension and subsequent pain
What is an intraluminal obstruction? How common is this presentation? How are these cases usually managed?
Impaction within the lumen of the intestine
Common medical condition in horses
Horse presents as cardiovascularly stable and can be managed in the field
What is a non-strangulating displacement? How are these cases usually managed?
Entrapment of intestine due to proximal part of the intestine being gas/fluid/ingesta filled
Can usually be managed medically
What can happen if a simple obstruction is not managed well medically?
Can become more severe and decrease perfusion to mucosa, which can compromise patient cardiovascularly (more serious case)
What is a strangulating obstruction?
Infarction - cut off blood supply to a portion of the intestine
Compromised blood flow to intestine as a result of twist/entrapment = ischemic necrosis
What kind of intervention is required for strangulating obstruction?
Surgical intervention required
Very painful - needs analgesia
How does a patient with strangulating obstruction typically present?
cardiovascularly compromised due to toxins in the blood - emergency situation
What kind of test should you perform to determine the severity of infarction in the horse?
Abdominocentesis of abdominal fluid
What are the top differentials for a horse with inflammatory/toxic colic (Hint - give LI and SI causes)?
SI - enteritis, strangulation
LI - acute colitis, diarrhea
What are the 5 main causes of colic?
Simple distension
Simple obstruction (impaction)
Strangulating obstruction (infarction)
Inflammatory/Toxic
Non-GIT (false) colic
What is the diagnostic approach for a colic work-up?
What are the 2 immediate assessments you must make when arriving on a farm to treat a horse with colic (immediate needs of the horse)?
Rapid assessment of cardiovascular status
Degree of pain
Heart rate is an important indicator of WHAT in the sick patient?
Cardiovascular system status
HR over ___ is associated with mortality rate of 38-55%
HR over ___ is associated with mortality rate of 83%
> 80/min
90/min
Abnormal color of ____ and altered ____ associated with 23-40% risk of post operative death (Hint - another important indicator of CVS status)
Severity of pain is associated with increased WHAT in the colicing patient?
higher risk of mortality
Pain is a very important indicator for the need for WHAT kind of intervention for the colicing patient?
Surgical intervention
What are the typical pain signs in the horse?
Recumbency, Restlessness
Flank Watching, Flehmen
Stretching, Kicking at abdomen
Pawing
Trying to go down
Rolling, Sweating
When seeing a colicing patient: What is step 2 after assessing the patient’s immediate needs?
Obtain a very thorough history
What is SHED-C (history)?
Signalment
Medical history
Environment
Diet
Complaint
What are some important questions to ask about a colicing patient’s history?
Age
Time of colic onset
Degree of colic shown
Any treatments given
Previous colic
Last passed feces
Management
Worming regime
What GI issue can increase the likelihood of colic? Why?
Intestinal parasites
Impaction in the intestine
You should always complete a thorough physical exam in a colicing patient, but you should especially focus on what?
Demeanor, signs of pain
Behavior, abrasions
TPR
CV status (MM, pulses, skin turgor)
GI borborygmi
Abdominal distension
Abrasions around the head suggest what kind of behavior in a colicing patient?
Rolling, recumbency
What can a depressed, quiet horse with many abrasions indicate in terms of colic?
Horse has likely had colic for a long time (long term colic)
Generalized, dull discomfort, no longer in severe pain
Now just very depressed, needs to be worked up
When should you take a horse’s temperature on physical exam?
Before rectal
What are your top DDx for colic in a febrile patient?
Typhylocolitis (inflammation of cecum and colon)
Peritonitis
Enteritis
Potential rupture?
What kind of gut sounds would you expect to hear with a strangulating obstruction?
Quiet or absent
What does a high pitched ping suggest on auscultation/percussion of a horse with colic?
Gas distension of a viscus (large intestine)
If you notice abdominal distension on a colicing patient, what does this tell you about the location of the lesion?
Suggests a large colon problem
What % of the abdomen can you palpate on rectal exam?
20-40% of the abdomen
How often can you reach a diagnosis based on rectal palpation of a colicing patient?
Often you do not reach a diagnosis
You use it as a tool to provide more information regarding severity of the problem and inform the need for surgery
What are the aims of rectal palpation/examination of a patient with colic?
Identify normal structures
Identify distension (localize to LI/SI)
- Identify gas vs. ingesta
Identify displacements
Identify abnormal structures
- Masses, etc.
What are the important tools you need in order to perform a proper rectal examination?
TAKE CARE
Restraint - physical or chemical
Spasmolytic (Buscopan)
Lubrication
What are the normal structures that you can feel on rectal exam of a horse?
What are the rectal exam findings that may indicate the need for referral?
Tightly distended loops of SI (bicycle tires)
Tightly gas distended large colon
Tight or painful taenial bands
Palpable hard masses Ex. enteroliths
What should be done in all (or most) colicing horses (for stabilization)?
Passing NG tube
Why should NG tube be passed in all (or most) colicing patients?
Horses cannot vomit
Stomach will rupture if it becomes too full, which is fatal for the horse
Better to pass NG tube to relieve gastric distension, fluid/gas will pass up NG tube
Saves patient!
What should you NEVER do when passing NG tube?
NEVER force anything, must be done very gently
What does reflux from NG tube over 2L indicate in the colicing patient?
Abnormal - suggests SI dysfunction
Are you allowed to give anything via NG tube if patient has reflux coming out?
No - do not give anything via the tube if you get any reflux
If reflux from NG tube is not spontaneous, what can you do?
Set up siphon, not likely to be spontaneous
What are the indicators for the need to refer a colicing patient?
Unrelenting pain or poor response to analgesics
Progressive abdominal distension
Absent borborygmi
Gastric reflux
Abnormal peritoneal findings
Abnormal rectal findings
Systemic deterioration
What are your main aims when formulating a treatment plan for a colicing patient?
Restore GIT function if required
- Surgical decompression, enterotomy, resection/anastomosis, correction of displacements
Control visceral pain
Soften and facilitate passage of ingesta
Correct and maintain dehydration and electrolyte, acid/base abnormalities
Treat endotoxemia
Treat ileus
What is the best short-acting visceral analgesic for horses?
a-2 agonist Ex. xylazine, detomidine, romifidine
What should you evaluate when using ultrasound to assess a colicing patient?
Evaluate peritoneal fluid, size of viscus (SI), position of viscus (LI), liver, kidneys, spleen
What is the FLASH protocol for abdominal ultrasound of the horse?
What should you do if you notice fluid distension of the stomach on ultrasound of a horse with colic?
Pass NG tube IMMEDIATELY!
When the left kidney is no longer visible adjacent to the spleen on U/S what is this suggestive of?
Nephrosplenic entrapment
What is normal vs. abnormal fluid obtained on abdominocentesis?
What is this fluid obtained on abdominocentesis suggestive of? What does the lactate indicate?
What values on BW are useful indicators of hydration status?
TP and PCV
What is lactate a useful indicator of?
Lactate useful indicator of tissue perfusion and helpful in identifying horses with cardiovascular compromise that will likely require referral
