Equine colic Flashcards
The most common equine emergency.
Colic is one of the most common causes for mortality and morbidity in the horse.
Colic is
a collection of clinical signs consistent with abdominal pain. It’s an umbrella syndrome, not a specific disease.
The same signs can be caused by extra abdominal sources
‒ Pleural cavity
‒ Urinary and reproductive tracts
“ähky”
Risk factors for developing colic. (6)
- Feeding
– quantity, feed type, frequency of feeding
– changes of food
– no regular watering (dry or cold seasons) - Parasitism and deworming
- Previous history of colic
- Medical treatment
- Housing (indoor stalling, changes in housing)
- Activity (exercise, changes in activity)
Clinical Signs of mild colic pain. (6)
The horse with mild pain may demonstrate one or more of the following signs:
* Inappetence
* Occasional pawing
* Turning the head to the flank (looking at the flank)
* Stretching out
* Lying down for longer than usual
* Quivering the upper lip
Clinical Signs of moderate colic pain. (5)
- Restlessness
- Pawing
- Kicking at the abdomen
- Rolling
- Turning the head to the flank
Clinical Signs of severe colic pain. (4)
- Sweating
- Violent rolling
- Dropping to the ground
- Extreme restlessness
Advanced intestinal necrosis and endotoxemia produce a state of indolence. The more severe the disease, the greater severity of pain.
How should you advise a colic-horse’s owner over the phone? (4)
- Withhold horse from feed and water
- Walk the horse (but no lunging, running or jumping)
- Give no drugs. They will mask the problem for 12h (flunixin). Needs to be examined before being given flunixin.
- Referral to the clinic if sending a vet out is unlikely or not possible.
Clinical examination in field, exception:
Exceptions are very painful horses! These are too emergent.
- Difficult to get heart rate anyway
- If very bad/painful just sedate immedaitely and place nasogastric tube immediately in that case!
If a horse is very acute - consider whether a clinical exam (including rectal) is even worth it. Potentially just sedate and send on way to referral center.
Euthanasia otherwise.
Case history in colic cases, should include: (9)
- Age, breed and use
- Duration of clinical signs
- The time when the horse was last observed normal
- Any medications (owners often just give flunixin they have lying aorund)
- Manure production, volume, character
- Previous problems
- Deworming historry
- Dental care history
- Access to sand?
Colic horse Clinical examination should include: (5+6)
Evaluate quickly from a distance:
* The type and severity of the pain
* General condition
* Abdomen distended or not
* Mentation
* Presence of wounds or lacerations (can indicate that the horse has been violently painful at some point)
HR, RR,
rectal temperature,
mucous membranes, CRT,
gut sounds
Describe Heart rate in horses with colic.
HR is a Very good indicator of severity of pain in horses.
The normal heart rate is 28 – 40 bpm.
- HR < 60 mild colic and usually respond to treatment.
- HR 60– 80 moderate to severe colic. Probably requires further care.
- HR >80 is severe pain colic and immediately life threatening. Place a nasogastric tube asap.
HR Elevations in horses with colic are result of anxiety, pain and hypovolemia.
NB Cardiac murmurs are common in colic horses.
The normal equine heart rate is
28 – 40 bpm
Describe Rectal temperature in horses.
Should be determined prior to rectal examination! Because a pneumorectum can lead to reduced temperature.
Causes of increased temp.:
* Colitis
* Enteritis
* Peritonitis
* Extra abdominal causes (pleuritis)
Decreased temperature and tachycardia are indicative of the development of circulatory
compromise and potential shock.
Describe Mucous membrane examination in colic horses.
The character and color of mucous membranes can reflect the circulatory status of the patient.
- Normal MM are pink and moist
- CRT 1,5 seconds or less
- Dry and tacky indicates dehydration.
- Dark or with a toxic rim indicates septic or endotoxic shock.
- Pale can indicate hemorrhage, severe pain, hypovolemia.
- Yellowish indicates jaundice and in horses that means its been fasting (not the same in small animals).
Yellowish mucous membranes in horses can indicate:
that the horse has been fasting
Horses have a unique metabolism where fasting (or anorexia) can reduce the liver’s ability to take up and conjugate bilirubin efficiently. This leads to an accumulation of unconjugated bilirubin, which gives the mucous membranes a yellowish tint.
Unlike other species, horses naturally have higher baseline bilirubin levels, and their bilirubin can rise quickly with fasting, even without significant liver disease.
Decribe Gastrointestinal Sounds on clinical examination of horses.
Can be:
* Normal sounds
* Absent – over a prolonged period absence of sounds can indicate ileus or obstructive disease.
* Increased GI sounds can indicate enteritis, spasmodic colic.
* Decreased
Are Caused by the sound of Gas.
Any changes are important.
Describe the 4 abdominal quadrants for listening to gut sounds.
Upper left: small intestine
Lower left: colon
Upper right: base of the cecum
Lower right: large intestine
Describe rectal examination of horses.
For Your own safety you must use Restraint (twitch) or sedation.
Only 40% of the abdomen can be explored by examination per rectum. Needs lots of practice!
You can tell:
* Normal vs abnormal
* Large bowels vs small bowel
* Gas
* Impactions
Be careful! Relaxation can take up to 30 seconds.
Use muscle relaxant Bysimin/Buscopan (hyoscine butylbromide, same as butylscopolamine) 20 mg/ml can be used for relaxation at a dose of 0,2 mg/kg/iv it makes 1ml/100 kg BW.
If fresh blood is present at the end of the rectal examination, a rectal abrasion or rectal tear should be suspected.
* Inform the owner
* TMS AB
Most common site for impaction in horse GI tract.
Pelvic flexure impactions occur frequently because this is a narrow, hairpin turn where ingesta must move from the left ventral colon to the left dorsal colon, often leading to feed material accumulating and causing obstruction.
is usually on the left side but when impacted can move and be felt centrally on rectal palpation.
Describe Nasogastric intubation in horses.
A nasogastric tube should always be passed in colic horses. Follow the ventral meatus. Purpose to Check for reflux and to give meds and fluids.
Reflux is when fluid stays “standing” in the stomach rather than moving forward like it should. GI contents can also come backwards along the tract - this is reflux. It can’t come all the way out cause horses can’t vomit. It counts as reflux when volume 2L+ comes out (ca 20L is maximum).
Reflux occurs in
- Enteritis
- Small intestine obstruction
- When the small intestine is compressed by the large intestinal obstruction or displacement.
It is NOT possible to completely flush the abdo cavity of a horse after GI rupture - always euthanasia.
biochemical changes elevated CK and LAC =
rhabdomyolysis
Routine biochemistry in colic horses?
Lactate!
Especially Important if fever persists.
FLASH is
Fast Localised Abdominal Sonography of Horses a scanning technique for colic patients.
Use of a low frequency probe.
Meant To aid decision making in horses with colic.
May be more accurate for detecting lesions requiring colic surgery versus rectal palpation.
Apply alcohol +/- gel to the hair coat.
Evaluate for:
◦ Intestinal position
◦ Contents
◦ Wall thickness
◦ Distension
◦ Motility
◦ Presence of free fluid
Left flank FLASH windows? (4)
Fast Localised Abdominal Sonography of Horses a scanning technique for colic patients.
Left:
1 - ventrum, probe caudal to sternum on ventral midline
2 - gastrosplenic window, 10- 15th intercostal spaces
3 - nephrosplenic window, probe into 17th intercostal space dorsally (left paralumbar fossa)
4 - left-middle-third, lower than nephrosplenic window
Right:
5 - duodenal window, 14-15th intercostal space
6 - right-middle-third, cecum in right paralumbar fossa
7 - cranial-ventral-thorax, immediately caudal to right triceps ventrally
Right flank FLASH windows? (4)
Fast Localised Abdominal Sonography of Horses a scanning technique for colic patients.
Right:
5 - duodenal window, 14-15th intercostal space
6 - right-middle-third, cecum in right paralumbar fossa
7 - cranial-ventral-thorax, immediately caudal to right triceps ventrally
Left:
1 - ventrum, probe caudal to sternum on ventral midline
2 - gastrosplenic window, 10- 15th intercostal spaces
3 - nephrosplenic window, probe into 17th intercostal space dorsally (left paralumbar fossa)
4 - left-middle-third, lower than nephrosplenic window
Pain always causes what in horses?
reduced GI tract motility - ileus
doesn’t matter where the pain is from, even orthopedic pain causes ileus
Describe abdominocentesis fluid analysis in colic horses. (5)
- Observe Color, smell
- Proteins should be less than 20g/kg
- WBC
- Lactate – Marker of tissue oxygen delivery and utilization.
- Peritoneal fluid color has been shown to be useful in helping to distinguish between surgical and medical cases of colic.
Why should I perform abdominocentesis? (5)
It gives you info:
- Obstruction of bowel without vascular strangulation or necrosis results in no changes in peritoneal fluid.
- Displaced or strangulated bowel results in increased peritoneal fluid volume, increased protein content due to lymphatic or venous obstruction.
- Necrotic bowel results in increased red blood cells and hemoglobin in the fluid due to vascular occlusion.
- Bowel Strangulation results in increased rbc + wbc count in peritoneal fluid. Color from golden to orange or red.
- Ruptured bowel results in increased wbc count and protein, sometimes fecal material in the fluid.
Types of Colic (6)
- Gas colic
- Spasmodic
- Small intestinal obstruction
- Small intestine strangulation or volvulus
- Large bowel impaction
- Large bowel displacement/volvulus
How to cause splenic contraction pharmacologically and why would you want to do this?
ventral colon moves dorsally and becomes entrapped between spleen, renosplenic ligament and left kidney = left dorsal displacement of colon
administer Phenylephrine to cause splenic contraction to decrease spleen size to increase chances of colon coming loose and returning to natural position.
Describe right dorsal displacement of the colon in horses.
Right dorsal displacement occurs when the pelvic flexure slides between the horse’s cecum and the body wall.
Large colon volvulus occurs when the whole structure of the colon flips over on itself.
Tx of colic involves: (4)
- Pain management with:
– Decompression with nasogastric intubation and removal of stomach fluids every 2 hours.
– Analgesics - Management of dehydration:
– oral fluid therapy (not for intestinal stangulation cases)
– IV fluids - Softening of impactions
- Stimulation of motility (there are No specific drugs to increase motility in the horse; motility is stimulated with analgesia and gastric decompression)
NSAIDs for horses in colic (2)
- Flunixin meglumine 1,1 mg/kg PO/IV q12h. Excellent analgesic for GI pain.
- Ketoprofen if you dont have flunixin, 2,2 mg/kg IV or IM
Alpha2 agonists for horses with colic: (2)
- Detomidine 0.01- 0.02 μg/kg
- Xylazine 0.25 – 0.5 mg/kg
Onset in 2 – 3 minutes. Analgesia often outlasts sedation which only lasts up to 30 min.
NB Potentially deleterious effects on GI motility.
Describe Opioids for horses with colic: (1)
- Butorphanol 0,02 – 0,075 mg/kg SC/IM
- or Butorphanol as CRI
moderate analgesic sedative
Very short half life. Cleared within one hour. Rarely used alone! Combine with alfa2 agonist.
Depresses bowel motility. Very effective for additional restraint if horses kick or are aggressive.
Describe Lidocaine continuous rate infusion (CRI) for colic horses.
- Very good analgesic for visceral pain
- Anti-inflammatory
- Prokinetic
- 1,3 mg/kg IV for 15 minutes, continue 25 – 50 μg/kg/min
- Consentration: 10g Lidocaine in 3 liters NaCl.
How to Soften impactions in colic horses: (4)
Impactions are very common. Diagnose by Rectal examination.
Give:
* Enteral fluids (cheap, safe; add 45 cc of pansalt/6L H2O), give up to 6L at a time into the stomach, every 2 hours.
* Rectal fluids
* Mineral oil by mouth
* Magnesium sulphate 0.5 – 1 g/kg (NB +2g/kg can already kill the horse)
Describe the giving of IV fluids in colic horses.
- Monitor HR, mucous membranes, urination
- PCV, Creatinine
- Use Crystalloids usually
- Consider colloids if:
– Hypoalbuminemia
– Resuscitation - Consider calcium:
– Hypocalcaemia as its common in colic.
– Very important in smooth muscle contraction.
– Requires very careful administration.
Maintenanace fluid rate in horses: 65 ml/kg in 24h.
Withhold colic horses from feed until: (4)
– Until analgesia has worn off
– Horse is behaving normally
– Manure has been passed
– Recheck the horse before refeeding
Always offer water and reintroduce feed gradually.
After tx of acute colic, if the horse recovers - what type of follow up should be done?
Consider the reason for the initial colic.
- Parasites
– Encysted strongyles (pictured)
– Check for tapeworms, anoplocephala perfoliata. Measure antibodies froom saliva or blood. - Teeth
- Sand potentially eaten?
- EGUS (equine gastric ulcer syndrome)
How to asses whether its a surgical colic?
- Pain
– Severity
– Response to pain medication - Pulse
- Reflux
- Peritoneal punctate color, opacity and Lactate.
- Rectal examination
- Distended or not
Referral
– Inform the owner about cost and possible complications of the colic surgery
– Prepare the horse with Medication and NG tubing.
– Call the referral hospital
Euthanasia? – Do not wait too long
Normal amount of fecal piles from a horse in a day?
10-12 piles
Prognosis after colic surgery?
Survival 50 – 90 %
Chronic problems – 5 %
Return to use 4 – 6 months
When flunixin is given orally, where is it absorbed?
through the oral mucosa
how to tell dorsal colon from ventral?
ventral always have the haustra
