LA Sx Exam #2: Colic Flashcards
(114 cards)
1
Q
Colic vs. true colic vs. false colic
A
> Colic = broad category of ABDOMINAL PAIN
- True colic = pain originating from the GI tract
- False colic = diseases of other non-GI systems that manifest as apparent abdominal pain, Ex: pleuritis or pneumonia, granulosa cell tumor (rupture and bleed), urolith, pellet in urethral diverticulum, testicular torsion, tetanus, pre-pubic tendon rupture
2
Q
Prevalence of colics and the need for surgical intervention
A
- Colics = 7% of practitioners calls
- 1% of colics = surgical
- Vast majority respond to initial medical tx or heal on their own
3
Q
Questions to ask, as a practitioner, when presented with a colic case (4)
A
1) Does the horse require surgery for dx or tx?
2) Doesn’t need sx - what is the appropriate tx?
3) Does need sx - should it occur or should the animal be euthanized?
4) Does need sx - what should be done to prepare it for referral
4
Q
Common cause of colic in 8 hour foal
A
Meconium impaction
5
Q
Common cause of colic in a broodmare that foaled 4 weeks previously
A
Colonic displacement or volvuli
6
Q
Common cause of colic in a 25 yo pony with mild/persistent signs of colic, with a serosanguineous abdominocentesis
A
Strangulating lipoma
7
Q
Sedation recommended for colic cases
A
> Alpha-2 agonists = xylazine (shortest acting, less Ileus) or detomidine
+/- Butorphanol for additional analgesia
- NSAID’s
- Anti-spasmodics, Ex: buscopan
8
Q
What sedative is not recommended for colic cases?
A
Acepromazine = provides minimal analgesia, will vasodilate and cause hypotension in already shocky/dehydrated animals
9
Q
What emergency treatment might you need to use in a horse with colic (should really perform in any colic patient)? What can it tell you?
A
> Nasogastric tube (esp if there’s evidence of gastric reflux, Ex: ingesta coming out of nose, reverse esophageal peristalsis)
- Can’t eructate or regurgitate, prevents gastric rupture
- Reflux of 1-2 L is normal
- Gives you an idea of the nature and quantity of gastric contents
- Use a large tube = decreases chance of blockage
- Use the siphon effect
- DO NOT add large volumes of liquid to the already distended stomach
- Normal pH = 3.0 (more basic = indicative of SI reflex with bicarb)
- See reflux of medications already given? May indicate ileus
More rare = trocharize the flank
10
Q
Questions to ask about in your history of a colic patient
A
1) Duration of clinical signs? How long?
2) Severity of colic signs? Stead, improving, worsening?
3) Passage and nature of feces? Small, hard, covered in mucus (impaction, prolonged time to excretion)? Diarrhea?
4) Feeding? Last meal? Off feed? Escaped and consumed highly fermentable apple or fresh grass?
5) Management changes? Exercise, stabling, transportation, fresh water availability
6) Age
7) Deworming history - ascarids, tapeworm, cyathostomiasis?
8) Vax history - rabies?
9) Previous strangles? Bastard strangles?
10) Regular dental care?
11) Recent injury or infection - hernia, edema, hemorrhage?
12) Breeding? - injury in mare during breeding, inguinal hernia in males
13) Recent colic or abdominal sx - aneurysms or adhesions, palpate ventral midline for scar
14) Pregnancy and uterine torsion
15) Color? Grey horses and melanomas
16) Medications - has anything been given (mask clinical signs?)
11
Q
Main clinical sign we use to determine the need for surgery
A
PAIN and the response to treatment (medication)
- Related to rapidness of distension development, degree of intestinal compromise
- Ex: pelvic flexure obstrurction = mild, low grade discomfort as ventral colon distends
- Ex: large colon torsion w/ rapid distension and ischemia = severe and unrelenting pain
- Consider the age/breed and horse
- Ex: younger horses and smaller horses/ponies are far less stoic than older or draft breed hores
- Foals = difficult, progress from intense pain to becoming depressed and dull
12
Q
Clinical signs of a mild colic
A
+ Yawning
+ Extended neck, stretch lip with Flehmen response
+ Teeth grinding
+ Anxiety
+ Looking at or biting at the flank w/ ears pinned back
+ Pawing at ground or abdomen
+ Groaning
+ Muscle tremors, esp in warm-blooded horses
+ Patchy sweating
+ Frequent posturing to urinate but only passing small amounts
+ Want to lean against a wall or lie on ground and frequently rise
+ Rolling
+ Resting in abnormal positions, Ex: dorsal recumbency, dog sitting (takes pressure off cranial abdomen)
+ Mild or intermittent signs of pain
+ Abnormal feces = diarrhea, foul smelling, hard, dry
13
Q
Clinical signs of severe colic
A
\+ Continuous pain \+ Violent rolling, kicking at belly \+ Total disregard for handler or self \+ Self trauma - excoriations of legs (thrashing), supraorbital processes above the eye \+ Generalized and profuse sweating \+ Distended abdomen \+ Protrusion of perineum from straining \+ Profuse diarrhea \+ Dyspnea \+ Reverse peristalsis or nasal reflux
14
Q
Reasons for pain in true colics (3)
A
1) Tension on hollow organs (distension)
2) Tension on the mesentery
3) Stretching of the parietal peritoneum
15
Q
Should we allow horses to roll with colics?
A
- If they’re willing to just sit dorsal, may be ok (should probably get them up to walk)
- Risks = twisting GI tract, rupture internal organ, fracture spinous processes of withers
- DO NOT walk to the horse to the point of exhaustion
16
Q
What may abatement of pain, accompanied by depression and deteriorating cardiovascular status suggest?
A
Non-viable intestine, no longer painful due to the destruction of its nerve supply
*Common causes = hypovolemia (sequestration of fluid in a 3rd space), endotoxic shock
17
Q
What does the duration of the response to analgesia indicate?
A
- Low grade pain that is easily relieved with small doses of alpha-2 agonists = medical colic
- Short term or complete lack of response to analgesia = surgical lesion
18
Q
Things to tell the owner/client to do before you get there
A
1) Remove all feed and water
2) Do not administer any home remedies (may mask clinical signs), with the possible exception phenylbutazone
3) Walk the horse WITHIN REASON (too much = exhaustion = poor anesthetic candidate)
4) DON’T GET HURT
19
Q
Parameters that help you evaluate the cardiovascular status of the patient
A
- Heart rate and rhythm = HR will rise with more serious conditions
- Pulse quality
- Color of mucus membrane - icteric (off feed, liver), brick red (endotoxemic), pale (internal hemorrhage), blue/grey
- Capillary refill time
- Hydration status (>70% = poor prognosis) = skin tent, PCV or TP
- CBC = PCV, WBC counts (increased with infectious, increases late in spasmodics, impactions, compromised bowel)
*Thrashing around of the head may make the mucous membranes (conjunctiva) look hyperemic
20
Q
Normal and abnormal heart rates for various colics, prognosis?
A
> > NORMAL = 36 bpm
- 40-60 bpm = likely a medical problem
- Nephro-splenic entrapment or colonic volvulus can be < 40 min (still serious)
- 60-80 bpm = consider laparotomy
- 80-100 bpm = almost certainly surgical
- > 100 bpm = very serious (indicative of endotemic shock)
21
Q
Minimal blood work recommended to perform with colic patients (4)
A
- PCV (>70% = poor prognosis)
- TP (plasma total solids)
- Blood gas
- Electrolytes
22
Q
True or false? Pain alone can increase heart rate and PCV?
A
True - splenic contraction = increased PCV (w/o dehydration)
23
Q
True or false? Stronger the pulse = better prognosis
A
True - weaker pulses indicate a failing heart
24
Q
Things to consider with abdominal auscultation and percussion
A
> 4 sections = dorsal, ventral, left, right
- Dorsal L = referred sounds from stomach and SI (often quiet in fasted horses)
- Ventral L & R = large colon, should have constant motility
- Borborygmi?
- Hypo or hypermotility?
- “Sand sounds” - like waves on a beach (absence is not exclusion)
- Tympany for distended sections of bowel
- Hypomotile = indicate ileus or obstruction
- Hypermotile = impending diarrhea, plus gas sounds
25
Things to consider with thoracic auscultation
- Abnormal sounds + fever - considered pleuritis or pneumonia?
- Recent trauma - diaphragmatic hernia?
26
What should you suspect if you're getting large amounts of fluid (> 1-2 normal liters) out of the nasogastric tube?
- Obstruction of the small intestine
| - Can be present with large colon distension (Ex: nephrosplenic displacement with pressure on descending duodenum)
27
How much fluid does the pancreas secrete with ileus?
4 L per hour - can produce gastric distension if not relieved (deflate every 2 hours)
28
Main diagnostic that helps us determine if the patient is surgical or not
Rectal palpation - assess bowel distension (tight taenial bands), thickness, position
* Only if it's safe for you or the horse (small sized, fractious animals, animals in severe pain)
* Only permits you to examine 25-30% of the abdomen (relying on the fact that distension will push things caudally)
29
Pros and cons of using xylazine
+ Short acting
+ Less likely to cause ileus
- Not the most effective sedative = may want to use detomidine for more profound sedation
30
Things you should be palpating via rectum in colic patients
- Bladder = commonly full because horses don't want to posture to urinate, check for wall thickening associated with cystitis or uroliths
- Vaginal ring in males = normal slits, ensure there's no inguinal herniation of bowel
- Uterus = pregnant? rupture of middle uterine artery?
- Ovary - granulosa cell tumor
- Intestine character = thickness (mural edema?), more persistent indentation with impaction
- Spleen = caudal border for blunting with engorgement from entrapments, space between splenic base and kidney
- Peritoneum - gritty with adherent plant material following rupture or with peritonitis
- Scrotum in males for hernia or torsion
31
Medical or surgical? Distended small intestines that feels large/firm, or large colon pushing into the pelvic canal
Surgical - if unsure, re-rectal later
32
Other diagnostics, besides history, clinical signs, CBC, chem, or rectal palpation (3)
1) Abdominal U/S - amotile loops of bowel, increased wall thickness (> 3 mm), fluid pockets for centesis
- Ileum is thicker than normal duodenum/jejunum
- Abnormal viscera = distends, becomes heavy, and falls ventrally
- SI intussception = "bulls-eye" appearance
2) Abdominocentesis - for patients not responding to medical treatment (not recommended for every colic, often inconclusive)
- Use teat cannula or 18-g needle
* Reflects changes within the peritoneum
- TP increases within 1 hour
- RBC's appear in 3-4 hours
- WBC's appear in 6 hours
* False negatives can occur (no fluid)
* Tap at least 3 sites
- Not getting fluid? = rock horse, hold off nostrils (take a large breath)
- Use in conjunction with U/S
3) Abdominal radiograph = maybe in small horses or foals (see enterolithiasis, sand impactions, diaphragmatic hernias)
- Requires a powerful mounted unit with grid
33
Risks of abdominocentesis (3)
1) Enterocentesis = hitting a loop of bowel, common with distended ischemic bowel (less common with teat cannulas), see green plant material (not necessarily ruptured bowel)
2) Leakage from bowel
3) Amniocentesis of the mare is pregnant
34
Interpretation of normal and abnormal abdominocentesis fluids
- Normal = straw colored clear
- Normal cell count (WBC's) = < 5 x 10^9 per L in an adult (less in foal)
- Normal total protein < 25 g/L
- Normal postpartum mares = WBC counts in normal ranges (may be higher in dystocias, fetotomies, assisted vaginal deliveries with NORMAL TP)
- Cloudy = WBC's, not increases in TP
- Clot due to fibrinogen
- Small amount of RBC's = secondary to centesis
- Large amount of RBC's = intraperitoneal hemorrhage, splenic puncture, hitting a skin vessel
* Splenic rupture = higher PBC than venous blood with no phagocytosis
- Brown/bloody fluid, degenerative neutrophils = late stage necrosis
- High WBC's and ingesta = ruptured viscous
- Enterocentesis > 450 x 10^9
35
Signs of ruptured bowel? Do you euthanize?
+ Degenerate neutrophils and bacterial presence from release of intestinal contents
+/- Plant material (may be walled off by omentum)
*Plant material on tap - may have performed an enterocentesis - REPEAT more caudally
*Requires other signs for euthanasia (not just green digesta)
36
Do we trocharize large bowel?
RARELY in general practice, but may do so prior to surgery
Locate distended viscous with percussion (commonly cecum in right paralumbar fossa)
Risk = leakage on ingesta, laceration of bowel
37
Criteria used for deciding when to perform abdominal surgery (8)
* PROMPT ID AND REFERRAL ARE CRUCIAL
1) Intractable pain not relieved by analgesics
2) Tympanitis that is not relieved medically
3) Abnormal rectal palpation (SI distension, colonic displacement)
4) Abnormal bowel on U/S (dilated, amotile)
5) Persistent nasogastric reflux
6) Abnormal abdominal fluid
7) Worsening clinical picture, Ex: markedly elevated HR, elevated PCV or TP
8) Impactions that don't respond medically
38
Things, as a practitioner, to do before referring a colic
- Fluids - ideally hypertonic with water/saline afterwards
- Broad spectrum antibitoics, Ex: gentamicin or penicillin
- NSAID's
- Nasogastric tube with gastric distension
- Sedation (degree depends on travel duration)
- Contact owner, WARN OF POTENTIAL COST
- Contact referral center
- Contact the insurance company
39
Can you see gastric distension?
No, enclosed in ribs
40
All about the small intestine (duodenum, jejunum)
- Duodenum = RIGHT SIDE, pass caudally near the right lobe of liver, right dorsal colon, right kidney
* Duodenum = short mesoduodenum, mostly fixed
* Jejunum = coiled and suspected by a LONG mesentery (trap in umbilical, inguinal, or epiploic foramens)
41
What helps us ID the ileum?
Terminal ilieum = anti-mesenteric band
| *Only ID along the mesenteric portion of the SI
42
Sequence of viscera in the GI tract
Esophagus > stomach > duodenum > jejunum > ileum (cecum) > right ventral colon > sternal flexure, left ventral colon > pelvic flexure > left dorsal colon > diaphragmatic flexure > LARGE right dorsal colon > small colon > rectum
43
Which portion of the cecum is attached?
Base of the cecum - connective tissue to peritoneum, etc.
44
Common cause and sites of impactions (4)
> Occurs where we see changes in direction or diameter
- RIGHT = Terminal ileum to base of cecum
- RIGHT = Cecum = NOT DUE TO change in direction/diameter
- LEFT = Pelvic flexure (sharp turn) = MOST COMMONLY
- Right dorsal colon = narrows into small colon
- Transverse small colon
45
Difference between torsion and volvulus
- Torsion = twist along the longitudinal axis
| - Volvulus = occurs along the root/longitudinal axis of the mesentery
46
Which is the only portion of the large colon that is attached?
Right dorsal colon
47
of taenia in various parts of the GI tract (cecum to caudal)
- Cecum = 4
- RVC = 4
- LVC = 4
- Pelvic flexure = 1 (can't feel, mesenteric)
- LDC = 3 (can't feel at all)
- RDC - 3 (can't feel it)
- Small colon = 2, can only feel one
48
Palpation of pelvic flexure
- One taenial band you can't feel (on mesenteric side)
- SMOOTH
- Similar size and shape of your knee
- Present in the LEFT VENTRAL abdomen
49
Palpation of the left dorsal colon
3 taenial bands = CAN'T FEEL, too cranial
50
Palpation of the left ventral colon
4 taenial bands = CAN'T normally feel, too ventral
51
If you palpate a large, distended viscous with taught taenial bands, which structure are you most likely palpating?
Left ventral colon - displaced or twisted (not normally palpated, too ventral)
52
How do you differentiate between distended small intestine and small colon?
- Presence of fecal balls? - Small colon
| - Presence of one anti-mesenteric taenia? - Small colon
53
True or false? You should not repeatedly dose a horse with flunixin without thoroughly re-evaluating the condition
True
54
Is phenylbutazone effective for treating colic pain?
Not really (maybe in mild cases)
Efficacy for NSAID analgesia = flunixin > ketoprofen > phenylbutazone
55
Anti-spasmodic we use and its effects
> Buscopan
- Relieve GI spasms
- Relax smooth muscle
- Anticholinergic = will raise the HR
* DOESN'T disguise worsening colic signs like flunixin
* Useful for relaxing the rectum to permit palpation
56
How quickly should mineral oil move through the GI tract?
> 4L should normally move through ~24 hours
| - Hypermotile GI tract = 12-18 hours
57
What is the most common form of colic?
Spasmodic
58
Dx? Sudden abdominal pain that subsides and recurs, borborygmi is present (often loud), vital signs (HR, RR) are only slightly elevated, normal MM, feces = normal to loose, normal rectal palpation (may feel abnormal small intestine)
Spasmodic colic
59
Cause or pre-disposing factors of a spasmodic colic
> Primarily due to poor management
* Intestinal parasites = tapeworms (not covered by ivermectin), small and large strongyles, cyathostomes
* Human error
- Rapid feed changes
- Large amounts of fermentable feed
- Drinking large amounts of cold water
- Changes in weather
- Poor teeth
- Hemorrhage = ileus induced by hypovolemia
- Sedation with alpha-2 romifidine
- Cribbing and ingestion of air
60
What is occurring pathologically with spasmodic colics?
Smooth muscle spasms = segments of distended bowel --> increased peristalsis and segmentation stretches autonomic nerve-R's = pain
61
Treatment of spasmodic colics
* Many will subside w/o treatment
* Treat if not showing clinical signs when you arrive, may relapse
- Analgesia = control the pain
- Laxative = aid in passage of ingesta (mineral oil via nasogastric, may mix with DSS surfactant)
- Antispasmodic = Buscopain
- NSAID's = Banamine
62
Should you purchase horse that has a history or recurrent colic?
No - may indicate unsoundness, may horses will go on to have an intestinal accident (tympany, colonic displacements)
63
Dx? Mild signs but increase with pain over time, (frequently) abdominal distension, feces are scant, dry, hard
Impaction
64
Can you feel the right dorsal colon on rectal palpation
No
65
Predisposing factors for impaction colics
- Cold and wet weather = common in FALL or winter
- Dry feed and poor water intake (long transport, shows with unfamiliar surroundings)
- Poor quality feed or fibrous food
- Poor teeth
- Foreign bodies = wood shavings, black rubber fencing, baler twine
- Sand ingestion
- Intestinal parasites
- Mares in late gestation = fetus impedes passage of feces (esp in small colon)
- Coastal Bermuda grass hay = cause ileal impactions
66
Pathogenesis of impaction colics
Coarse dry feed = irritating to muscoa > produce a spasm > fluid is resorbed, bowel distension produces pain
* Motile proximal with relaxation distal
* Abnormal peritoneal fluid later with release of protein and WBC's (or with necrosis and leakage)
* Can progress to peritonitis and endotoxemia
67
Causes and clinical signs of cecal impactions
> Primary and secondary to routine sx
- May be associated with Banamine administration
+ Primary = chronic, mild attacks for up to 3 weeks
+ Secondary = recover from anesthesia, but is anorexic and has reduced fecal output
+ May be defecating or have diarrhea (occurring caudal to the impaction)
- Less common = sudden and acute motility disorder = distension and rupture
68
Dx and tx of cecal impactions
> Dx = rectal palpation, right sided distension with a taught medial taenial band
> Tx: controversial, can be medical or surgical based on degree of distension
- Medical = only if distension is mild and ingesta is easily indented = withhold food, laxatives (DSS, oil) until the cecum palpates normal
- Sx = typhlotomy to empty, +/- bypass
69
Causes and clinical signs of ileal impaction
> Primary = SE US with costal Berumda grass ingestion
+ Primary = acute signs, consistent with complete blockage
> Secondary = due to muscular hypertrophy of the ileum = IDIOPATHIC, causing luminal constriction
+ Secondary = chronic, low grade colic
70
Dx and tx of ileal impactions
- Dx = rectal palpation or exploratory laparotomy
- Medical therapy (laxatives, withhold feed) may be tried
> Secondary = caused by hypertrophy of muscular layers
- Secondary Tx = surgically bypass the area
71
Dx? Neonate foal (24-48 hrs), more common in males, straining, arched back, partial anorexia
Meconium retention
72
Who do we see meconium impactions in more often - colts or fillies?
Colts - thought to be due to their more narrow pelvis
73
Dx of meconium impaction
Digital palpation of rectum
If not, consider using radiography
74
Tx of meconium impactions
- Warm, soapy water enemas
- Acetylcysteine = breaks down mucoid component of meconium (EXPENSIVE) for more problematic cases
+/- Mineral oil supplementation if not responding
- RARE surgical laparotomies
75
General tx of impactions
- Analgesia with NSAID's
- Water and laxatives by NG tube (+/- DSS with oil)
- Parenteral or nasogastric over hydration with balanced electrolytes
- Withhold feed until impaction is cleared, then begin with a laxative/soft diet
*Signs of increasing pain, abdominal distension, or changes in peritoneal fluid = SURGERY
76
Dx of sand impactions
- Sand "wave crashing" sound on auscultation
- Gritty feel on rectal palpation
- Feces + water in glove = sand will separate out
- Sand on abdominocentesis
- Abdominal rads
77
Most common sites of sand impaction
RDC > transverse colon > LDC > pelvic flexure > sternal flexure > LVC > RVC
78
Dx? Anorexia, depression, DIARRHEA, depression, mild to moderate abdominal pain, weight loss
Sand impaction (sand is abrasive to mucosa = diarrhea)
79
Prevention of sand impactions
- Do not feed from the ground
- Restrict pasture access
+/- Pysillium (Metamucil) = absorb water in intestines, form a gel-like substance = increases intestinal bulk = stimulate motility (MAY NOT REALLY BE EFFECTIVE)
- Analgesia
- Soften obstruction with mineral oil +/- DSS, salt or other osmotics, fluids systemically or orally to overhydrate
* Mineral oil doesn't really break it up, but lubricates the impaction
* Surgery = severe pain, bowel blockage, changes in peritoneal fluid
80
Complications of impactions
- Recurrence
- Peritonitis
- Diarrhea/endotoxemia if the colon is badly abraded
81
Where do fecoliths and foreign bodies commonly block in the GI tract? Signalment? Tx?
>> Transverse or small colon
- Common in young horses, ponies, mini horses
- Tx = surgical removal
82
Composition and common site of obstruction of enteroliths
> Mg, struvite (ammonium phosphate)
* Common in SW US
- Frequently impact the RIGHT DORSAL COLON
83
Cause and clinical signs of enteroliths
- Commonly form around a nidus (foreign body)
- Pathogenesis is unclear (maybe high Mg and NH4 in diet)
*Common in older animals (majority = 5-10 yrs)
+ Intermittent colic as the roll in/out of blockage
84
Dx and treatment of enteroliths
- Dx: rads in young horses, exploratory laparotomy
* Difficult to palpate
* Peritoneal fluid normal unless necrosis
- Tx: enterotomy and removal
85
Common age of ascarid infection
< 1 year of age (seem to develop resistance > 1 yo old)
86
True or false - finding ascarids in the gastric reflux or feces are diagnostic of ascarid colic and impaction
FALSE - highly prevalent in animals
87
Pathology of ascarid impaction
Young horse, infected early in life (common in jejunum or terminal ileum) = common following deworming, worms die, embolize, and block GI tract
88
Dx? "Dog sitting", retching or gurgling sounds, reverse peristalsis of the esophagus, sour smell to breath, ingesta from the nose, spleen palpated per rectum (not normally that caudal)
Gastric distension and/or rupture
89
Causes of stomach rupture (3)
> Primary = gas production from eating highly fermentable feeds (grass, apples, finely ground grain, etc)., following hard work
> Idiopathic
> Secondary to small intestinal obstruction
90
Dx? Colic was violent and sudden became very quiet (2)
1) Got better
2) Gastric distension was relieved by rupture, animal will die of endotoxemia if not treated
+ Rectal palpation = floating feeling (ingesta separating out ingesta), grittiness due to ingesta/fibrin adhered to tissues
91
Tx of gastric distension
- Pass nasogastric tube (leave for several hours)
- Gastric lavage with a small amount of DSS and warm water may help relieve ingesta
* DO NOT OVERFILL THE DISTENDED STOMACH
92
Dx? Abdominal distension, dyspneic, tachycardia, inability to rectal palpate (can't get hand in), ping on percussion of abdomen
Tympanitic colic
*Can be shocky due to decreased venous return or dyspneic due to diaphragm compression
93
Causes of tympanitic colic (3)
1) Physical obstruction
2) Ileus
3) Error or sudden changes in feed, Ex: highly fermentable feeds
94
Tx of tympanitic colic
* ANALGESIA
- Trocharization if there is marked distension or absent peristalsis
- Exploratory celiotomy
95
Dx? Acute onset of mild to severe abdominal pain, depressed/absent borborygmi, injected MM, prolonged CT, moderate to severe SI intestinal distension (may be able to palpate it rectally), gastric reflux (reddish brown, fowl smelling, basic pH)
CAUSE?
Duodenitis, proximal jejunitis
*Thought to be due to Clostridia or Salmonella
96
Tx of duodenitis and proximal jejunitis
> Difficult to differentiate from other SI obstructions
- IV fluids
- Gastric decompression via NG tube every 2 hrs until motility returns
- Analgesia
- Withhold food until gastric reflux ceases
- NSAID's
+/- Penicilin or aminoglycosides (for Clostridia)
- Sx = less success than medical tx = red/yellow streaking of bowel, surface mottled with petechiae or ecchymotic hemorhage, thickened wall
97
Difference between incarceration and strangulation? Associated pathology?
- Incarceration = bowel is trapped by STILL VIABLE
- Strangulation = bowel is trapped, partial or complete VASCULAR OCCLUSION
- Distension > fluid distension and increase in pressure = secrete more fluid, increase in intestinal motility (try to relieve obstruction) > eventually becomes ileus
* Strangulation = added component of vascular compromise = rupture
98
Do we commonly see gastric rupture with large bowel obstructions or strangulations?
No
99
Dx? Foal to yearling with acute and severe abdominal pain, gastric distension and distended coils of SI
Small intestinal obstruction or strangulation
100
Dx and tx of foal SI strangulation
- Dx = difficult, foals often progress through colic quickly to depression
- Tx = resection and anastomosis
101
Origin of strangulating lipomas? Who do we seem them in?
- Older horses ( > 12 yrs) and ponies
- Fatty tumors suspended from the mesentery
* Wraps around intestine = caught in mesentery = strangulation of bowel occurs in SI and small colon)
102
Are SI strangulation into umbilical hernias common in horses?
NO - may become trapped, non-reducible, adherent to wall, form an abscess = Rickter's hernia
103
Are diaphragmatic hernias common?
Not really - may present with dyspnea, dx w/ rads or exploratories (hard to hear on auscultation), small sized hernias are more problematic
104
Mesodiverticular bands
> Congenital vitelline abnormality
- Failure of the vitelline artery and associated mesentery to atrophy during early embryonic development (near yolk sac remnant)
- Usually distal jejunum from mesentery to anti-mesenteric border
>> Blind triangular pocket = entrap intesintes
105
Meckel's diverticulum
> Congenital vitelline abnormality
- Remnant of omphalomesenteric/vitelline duct that connects embryo GI tract to yolk
- Conal extension from bowel = can become impacted or inflamed
- Can rupture = peritonitis
- Can strangulate intestine
106
Most common site and age of intestinal intussception
- Most common = ileocecal intussception
- Common in foals and animals < 3 yrs old
*Common with enteritis or intestinal worms
+ "Bull's eye" on cross section on U/S
107
What should you do with every stallion who is exhibiting signs of colic?
Scrotal examination - palpate inguinal rings
108
Where is the large colon attached to places? Where do torsions commonly occur?
Base of cecum, where it ends at the small colon
Can occur (longitudinal torsion) at LDC, LVC, free portion of RDC and RVC
* Dx 180 degree rotation = palpate taenial band on LVC (not palpable on LDC)
* Can deteriortate quickly = death 4-24 hour, irreverisble bowel damage (mural edema, venous thrombosis, necrosis) in < 2 hrs
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Who is at greatest risk for large colon torsions?
Broodmares in late gestation and after parturition (up to 3 months) = stretched abdominal musculature allows for greater colonic movement
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Dx? Progressively worse colic signs, reduced/absent fecal output, normal to transudate (high protein) abdominal fluid, palpation = gaseous colon distension (tight taenial bands) in the left dorsal abdomen
Left dorsal displacement of the left colon, or nephrosplenic entrapment
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Pathology of nephrosplenic entrapment of left dorsal displacement of the left colon
Left large colon (LDC and LVC) slips between the spleen and body wall (may be due to gaseous distension and rising), left colon commonly rotates
*Palpated distension in the left dorsal abdomen - distended spleen, spleen displaced medially
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Is the heart normally high or low with nephrosplenic entrapments?
Usually unusually low
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What you can feel on rectal (SP no ML)
Left side = pelvic flexure, caudal left dorsal/ventral colon
| Right side = right dorsal (rarely), right ventral (unheard of), mainly cecum
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What you can feel on rectal (Dr. Peek)
Left side = pelvic flexure
