Lecture 3: Introduction to Equine Colic Flashcards
what is colic
Abdominal pain, GI origin
What is the most common cause of equine mortality
Colic
What are some things that can cause false colic
Myopathy, urinary obstruction, uterine torsion/contraction, peritonitis, pleuritis
What are some signs of colic
Pawing, lying down, rolling, backing up, stretching out, looking around at abdomen, rolling lips (flehmen)
What is the number one problem with colic
Pain- sympathetic discharge leads to ileus, bowel shutdown, gas distention, displacement and strangulation
Any bowel compromise can lead to ___, ____, ___ with or without rupture bowel
Endotoxemia, shock, and death
How can colic lead to endotoxemia, shock and death
Normally the mucosal barrier is preventing the endotoxins from entering but a compromised bowel they can become absorbed
What are the origins of pain in colic
- Spasm
- Distention (Gas, visceral pain)
- Ischemia/hypoxia
- Inflammation
- Peritonitis-parietal pain
What can cause distention (gas, visceral pain)
Primary flatulence, proximal to obstruction, ileus
What is one of the most painful conditions in colic
Gas distention
What happened
strangulation obstruction
What happened
Strangulation obstruction—> epithelium is gone so endotoxins can rush in and blood also rushes in but venous outflow is blocked
What wrong
Ischemic strangulation obstruction- no blood but epithelium/villi gone
What are some specific questions to ask for colic history
- Degree and change in pain
- Last defecation
- Sweating
- Signs of pain
- Response to treatment
- Previous colic or abdominal surgery
- Duration of colic
- Last time fed-food and water
- Changes to food/water, medication, housing, travel, exercise, other horses
- Exposure to foreign bodies
- Pregnancy
- Recent worming
- Recent trauma, injury, or illness
What should you be evaluating related to pain in PE
Severity, continuous/intermittent, response/duration to pain control medication
What are some attitude behaviors in horses with colic
Depressed, anxious, intangible
Normal or abnormal MM?
normal
Normal or abnormal MM?
pale- beginning of shock, decreased BF, or so distended can’t breath
Normal or abnormal MM?
cyanotic rim- vasoconstriction
Normal or abnormal MM?
Vasodilatory stage of septic shock
On PE temperature in increased what does that tell you
Enteritis, rarely surgical
On PE temperature is decreased, what does that tell you
Shock
If pulse is bounding what does that tell you
Vasodilation
If pulse is weak what does that tell you
Shock
What are some reasons that respiration effort can increase
Abdominal gas distention and diaphragmatic hernia—> suffocating
You auscultate the abdomen during a colic, what are you likely to hear
Decreased/absent gut sounds due to pain resulting in sympathetic discharge—> decrease GI motility
Spasms- short not long and productive
Tympany- gas distention
What is ballottement
Percussion test where you poke abdomen and can sometimes see a fluid wave
When is it common to see a fluid wave
Foals with uroperitoneum
How can you assess parietal pain
Secession-depress and release abdomen by pushing fist into flank
Where do you listen for sand accumulation
Near xiphoid, ventral abdomen
What is the point of passing NG tube
Reflux- assessing for accumulated fluid in stomach
How do you perform NG tube for reflux purposes
Pump in water and then lower to create a siphon
In a normal rectal exam where is pelvic flexure
Left side
In normal rectal exam how should dorsal and ventral colon feel
Dorsal colon: smooth
Ventral colon: haustrae
T of F: SI is easy to find on normal rectal exam
False!
In normal rectal exam where should cecum be
On the right
In a normal rectal exam what should cecum feel like
Haustrae present, slight distention, presence of medial band
Where should spleen be in normal rectal exam
Against left abdominal wall
What quadrant would you check for nephrosplenic
Left dorsal quadrant
If there is fluid in abdomen what does it feel like
Arm floats in space
What part of intestines can occupy nephrosplenic space
Colon
What are some SI rectal exam abnormalities
The fact that you can feel them, mild distention (proximal enteritis), thicker bowel wall, taut distention is serious finding
What are the heart rate ranges for good, guarded and poor prognosis
Good: 40-59
Guarded: 60-100
Poor: >100
What are the MM colors for good, guarded and poor prognosis
Good: pink
Guarded: red
Poor: cyanotic
What is the MM refill time for good, guarded and poor prognosis
Good: 1-2 sec
Guarded: 3-4 seconds
Poor: > 4 seconds
What is PCV for good, guarded and poor prognosis
Good: 35-45%
Guarded: 45%-65%
Poor: >65%
What is peritoneal total protein in good, guarded and poor prognosis
Good: <2.5g/dl
Guarded: 2.5-4.5g/dl
Poor: >4.5g/dl
What does PCV measure
Hydration/metabolic status
What does an increase WBC tell you
Infection, stress, rarely colitis
What does decrease WBC tell you
Endotoxemia-enteritis
What does a normal CBC on horse with colic tell you
Displacement, strangulation
What values do you want to correct on chemistry to improve bowel function
Electrolytes (K, Na, Ca, Mg)
What should normal lactate value be
<2.5mmol/l
What are the normal electrolyte values for Na+, K+, Cl-, and HC03
Na+: 135-145 meq/l
K+ 3.5-5.5meq/l
Chloride: 98-108 meq/l
HCO3 22-30meq/l
What is lactate value for 90% survival
<7.5mmol/l
What is lactate value for 60-70% survival
<7.5
What is lactate value for 20-50% survival
7.5-10
What is lactate value for <10% survival
> 10
What is PCV for 90% survival
30
What is PCV for 60-70% survival
40
What is PCV for 20-50% survival
60
What is PCV for <10% survival
> 65
When collecting peritoneal fluid you should be cautious if bowel is ___ or ___
Heavy or distended
What is the result of puncturing colon during peritoneal fluid collection
Punctured colon will be fine but WBC will go up so information is useful
T or F: foals punctured colon seals right up so no worries if you puncture
Does not seal up so be careful
What are two possibilities if you get frank blood in peritoneal fluid tap
- Splenic tap
- Hemoperitoneum
Tap more than one site to determine splenic vs hemoperitoneum
How should normal peritoneal fluid appear
Clear yellow
If peritoneal fluid is cloudy/turbid what does that tell you
Increased WBC
If peritoneal fluid is serosanguinous what does that tell you
Bowel wall leaking
Is peritoneal fluid has feed and bacteria in it what does that tell you
Intestinal tap or perforation
What should total protein be from peritoneal tap
2g/dl or less
If total protein is increased in peritoneal fluid what does that tell you
Bowel wall is leaking or peritoneal inflammation
What is normal WBC in peritoneal fluid
300
What is normal lactate value in peritoneal fluid and if it is abnormal what does that mean
Normal: 2mmol/l
Abnormal: dying bowel
How can ultrasounds be useful in colic or colic like situation/what can you visualize
- Small bowel distention
- Thoracic contents
What can you visualize with radiographs in colic situations
- Thoracic contents
- Enteroliths
- Foals-meconium- small intestinal distention
What is gastroscopy used to visualize
Gastric ulcers
Identify which one is normal vs abnormal and what is wrong
Top: normal, spleen (white), intestines (black)
Bottom: abnormal- colon in nephrosplenic space
What does this show
free fluid- black area
What do 1-3 show
- Distended SI
- Thickened SI
- Sand in colon
What is this
enterolith
what is the sand test
Mix manure with water in bag or rectal glove- sand will settle to bottom- test is positive
Sand can erode the colonic mucosa leading to ___
Endotoxemia
T of F: you can perform a rectal exam on foal
False
T or F: foals are more likely to have WBC in peritoneal fluid without infection
True
What are the main objectives of medical management of colic
- Pain control- most important- stop sympathetic discharge so bowel can start working
- Hydration
- Electrolyte and acid-base balance
- Endotoxemia and sepsis
- Regulation of intestinal motility and transit
What are some short duration pain relievers for colic
Alpha 2 agonists:
1. Xylazine
2. Dormosedan
What is dose for xylazine in pain control for colic
0.5-1mg/kg IV
What is dose for dormosedan in pain control for colic
0.01-0.02 mg/kg IV
What drugs can be used to reduce pain in colic and also have anti-endotoxin effect
NSAIDS
1. Banamine
What is the dose for bananime in pain control for colic
1.1mg/kg IV
What is a short acting anti-spasmodic agent for colic
Buscopan/N-butylscopolammonium bromide
What is dose for Buscopan to tx spasmodic colic
0.3mg/kg IV
What drugs can be used to control pain in colic but caution because they inhibit motility
Opioids
1. Butorphanol
What is dose for butorphanol when treating colic
0.02-0.03mg/kg IV
What drugs do you want to avoid or use educated caution in colic
- Opioids- butorphanol- inhibit motility
- Acepromazine- vasodilator- potentiates shock- can collapse
- Motility stimulants- increase spasm/pain, potentiate rupture
- Dioctyl sodium succinctness (DSS)- enhances Mg absoprtion
What oral treatments can be passed through NG tube in colic
- Mineral oil- lubrication, prevents water absorption, transient marker
- Laxatives: magnesium sulfate, psyllium
- Rehydration- water and electrolytes
- Absorbents- charcoal, biosponge- for endotoxemia
How can mineral oil be used to indicate functioning GI
Can pass through NG tube and if it shows up in feces bowel is working and can go back on feed
What laxative is good to prevent Sand colic
Psyllium
What is the maintenance IV fluids for colic
50-60 ml/kg/day
How do you determine amount of liters needed to correct hypovolemia
= % dehydration (BW in kg)
How much calcium should horses receive in IV fluids
5-20mL of 23% calcium gluconate per 1L of fluids
T or F: if a horse is refluxing then you should pass mineral oils and laxatives through NG tube
False!
When do you put your horse back on feed after colic
If nothing is coming out, don’t put anything in
Oil is good marker in feces
What are some indications for surgery in colic
- Persistent intractable pain
- Incriminating rectal findings
- Metabolic status
- Peritoneal fluid findings
- Duration of above