Equine Colic Flashcards Preview

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Flashcards in Equine Colic Deck (52)

What is the #1 predisposing factor for colic in horses?

improper management


What are the most common locations for impaction in the horse?

  • Pelvic flexure
  • Right dorsal colon
  • Transverse colon
  • Small colon
  • Stomach


Where are sand impactions most commonly observed in horses?

Right dorsal colon

  • Diagnosis:
    • ​Auscultation (sounds like a beach!)
    • Fecal float/sink
    • Abdominocentesis - sand


Type II cecal impactions in horses are typically the result of:

cecal dysfunction


T/F: Abdominal ultrasound is a routine part of the colic exam


Can confirm LDD, SI distention, bowel thickening, free fluid. Excellent tool for evaluating the GI in real time


What are the 7 locations on the horse that are examined using the fast localized abdominal sonography of horses (FLASH) ultrasound technique?

  • Left side:
    • 1 - Ventral abdomen
    • 2 - Gastric window
    • 3 - Nephrosplenic window
    • 4 - Left middle 1/3 of abdomen
  • Right side:
    • 5 - Duodenal window
    • 6 - Right middle 1/3 of abdomen
    • 7 - Cranial ventral thorax


Where is an abdominocentesis performed on a horse?

On or to the RIGHT of ventral midline & caudal to the xiphoid


Normal lactate level in peritoneal fluid of a horse should be _____ 



Normal WBC in peritoneal fluid in an adult horse should be _____



T/F: Normal fluid on an abdominocentesis should be serosanguinous and turbid


It should not be that.


What is the minimum pre-op bloodwork prior to colic surgery?

  • PCV/TP
  • Lactate
  • CBC with differential
  • Fibrinogen
  • Glucose
  • BUN/Creatinine

Helps assess prognosis and help determine likelihood of intra/post-op complications


What is the best overall surgical approach for colic surgery?

Ventral midline approach

  • Can exteriorize 75% of GI tract
  • Minimal hemorrhage, strong closure
  • Unable to exteriorize stomach, duodenum. distal ileum, base of cecum, distal RDC, transverse colon, terminal small colon


Abdominal exploration in the horse should start at the __________



When exploring the abdomen in the horse, you begin at the cecum. If you follow the lateral band to the cecocolic band, you will reach the ________

Right ventral colon


When exploring the abdomen in the horse, you begin at the cecum. If you follow the dorsal band to the ileocolic fold, you will reach the ________

antimesenteric band of the ileum


The duodenum is fixed to the dorsal body wall and transverse colon by the __________ ligament

duodenocolic ligament


What is the gold standard for assessing tissue viability?


Not very practical though unfortunately, so we rely on gross clinical assessment, which is only ~54% accurate


 This 14 year old QH gelding was normal this morning and at lunch, but was severely painful this afternoon.

Rope horse, eats grass/alfalfa mix, and pellets. Up to date on vaccines and deworming. No history of previous colic and no meds

Physical Exam: Temp: 100.8, HR: 80, RR: unable d/t pain, mm: “muddy”, CRT: 3, GI neg all quadrants. Evidence of self induced trauma over head/eyes

Based on the PE findings, what is your next step?

  • Rectal exam
  • Sedation/pain management
  • NG tube
  • Bloodwork

Sedation/pain management

Then NG tube


An owner found her 8 year old Warmblood mare violently colicky. The mare has a foal and the owner is concerned for the foal's safety. The mare foaled 8 weeks ago and the foal is doing great (this is her 3rd foal). Current on vaccines and deworming. On spring pasture. The owner gave 10 mL Banamine PO prior to calling.

Based on this information, what is your top differential?

Colon Torsion

Other differentials include mesocolon tear, LC displacement, or other intestinal accident.


Which of the following would be a likely pre-op drug protocol for colic surgeries?

  • K+ Pen
  • Gentocin
  • Banamine
  • Tetanus toxoid
  • IV Fluid (LRS)

All of the above


What structure is Justin Beiber pointing to?

Pelvic Flexure


What is the daily maintenance fluid rate for post-op colic horses?

50 mL/kg/day

Don't forget to add losses to maintenance


After colic surgery if your patient has hypocalcemia that is refractory to therapy, this may indicate __________


  • High prevalence of hypomagnesemia post-op due to increased requirements of critically ill patients
  • Can add 150mg/kg/day of MgSO4 in fluids for maintenance supplement


When supplementing potassium in a horse, it is important not to give more than ____ mEq/kg/hr

0.5 mEq/kg/hr

Usually add 80mEq to a 5L bag


When do you discontinue meds after colic surgery?

When the patient is eating, afebrile, normal CBC


What are the components of management for post-operative endotoxemia?

  • Flunixin Meglumine (low dose)
  • Meds to chelate endotoxins
    • ​Di-tri-octahedral (DTO) smectite (Biosponge)
    • Polymyxin B (binds endotoxin)
      • ​Binds lipid A, neutralizes endotoxin
    • Hyperimmune serum
    • Plasma
  • Heparin therapy (in cases of DIC)


What is the most common lesion in horses leading to post-operative ileus?

Strangulating SI lesion


T/F: Lidocaine CRI helps inhibit free radical production



For treatment of POI in horses, a Lidocaine bolus can be given to directly stimulate smooth muscle and inhibit free radical production


For treatment of POI in horses, a Lidocaine CRI can be given to directly stimulate smooth muscle and inhibit free radical production.

DO NOT BOLUS! This can lead to muscle fasciculations, ataxia, and seizures.


Metoclopramine stimulates smooth muscle in __________ and __________

Metoclopramine stimulates smooth muscle in stomach and small intestine

  • Increases ACH release via:
    • ​DA1 and DA2 antagonism
    • 5-HT4 agonism and 5-HT3 antagonism
  • Dose: 0.04mg/kg/hr CRI
  • Toxicity/Extrapyramidal effects:
    • ​Excitement, restlessness, sweating, seizure


The most common complication from incisional infection is:

incisional hernia

Do not repair for 3 months - give time for formation of fibrous ring to so you have tissue that can hold your suture. Otherwise you will have a failed repair


Abnormal abdominocentesis along with a serum-peritoneal glucose difference >___mg/dL is indicative of peritonitis

>50 mg/dL

Abnormal abdominocentesis along with a s​erum-peritoneal glucose difference >50mg/dL is indicative of peritonitis


Peritoneal pH <____ with peritoneal glucose diagnostic for peritonitis>

Peritoneal pH <7.2 with peritoneal glucose <30mg/dL is diagnostic for septic peritonitis


Age, gender, and signalment can rule in or out many differentials for colic. In newborn foals, what are your top differentials?

  • Meconium impaction
  • Gastric ulceration
  • Enteritis
  • Inguinal hernia with ruptured tunic
  • Sepsis


Age, gender, and signalment can rule in or out many differentials for colic. In 2-5 day old foals, what are your top differentials?

  • Ruptured bladder
  • Gastric ulcers
  • Enteritis


Age, gender, and signalment can rule in or out many differentials for colic. In older foals, what are your top differentials?

  • Gastroduodenal ulcers
  • Enteritis
  • SI volvulus
  • Intussusception
  • Gastric outflow obstruction
  • Impaction (Ascarid)


Certain breeds tend to have certain causes of colic. QH fillies often develop ________



Certain breeds tend to have certain causes of colic. TB colts tend to develop ________

ruptured bladder


Certain breeds tend to have certain causes of colic. Minis tend to develop ________

small colon obstruction


With regard to colic in foals, fillies are more predisposed to ________, whereas colts are more predisposed to ________

  • Colts:
    • Meconium impaction
    • Inguinal hernia
  • Fillies:
    • Ruptured bladder (at urachus)
    • Ureteral abnormalities


This type of grass hay has been associated with ileal impactions in the horse:

Coastal Bermuda


This procedure is performed during colic surgery for horses with surgical impactions:

pelvic flexure enterotomy


During a colic episode a NG tube is passed and positive net reflux is obtained. When this happens this treatment is often given via the NG tube:

no treatment


This lesion causes colic in horses and is often treated by jogging the horse after pharmaceutical administration:

nephrosplenic entrapment


In a colicking horse with a sand impaction, the majority of the sand is found in this specific portion of the GIT:

right dorsal colon​


This is a common complication after SI surgery in the horse:

Post-op ileus


This type of colon obstruction causes severe congestion and edema in the mesentery and affected colon:

hemorrhagic strangulating obstruction


Identify this structure:

small colon


These are potential predisposing factors for colon torsion in horses:

Recent parturition, recent access to lush green grass, and recent dietary changes


It is common to see decreased levels of this mineral post-operatively due to increased requirements in critically ill patients:



T/F: Cribbing predisposes horses to epiploic foramen entrapment



What major complication is associated with surgical correction of epiploic foramen entrapment (EFE)?

Portal vein tear

Portal vein tear leading to fatal hemorrhage. Prognosis with fatal hemorrhage is not good.

It's bad.