Chapter 38 - Transverse and small colon Flashcards
The transverse colon is a continuation of the right dorsal colon where is situated? What is the vessel connected?
Begins at 17th 18th thoracic vertebra, passes from right to left, cranial to cranial mesenteric artery
The small colon is situated where in the abdomen and how long is it?
- Left CdD quadrant
- 3,5 m long, 710 cm diameter
-Suspended by descending mesocolon (mesentery to mesocolon), fat
SC It is connected dorsally to __ name organ and by ______ name the structure?
Connected dorsally to pancreas and dorsal abdo cavity and by short transverse mesocolon to root of mesentery –> prohibits exteriorization
The transverse colon is connected by which fold?
Duodenocolic fold that connects transverse and small colon to duodenum
What is the blood supply of the small colon?
a - arcuate artery
b - marginal artery
c - secondary arcade
d - long artery
e - small branch supplying mesenteric tenia
f - small branch to mesocolon
Which breeds are predisposed to small colon disease? is there a predisposition of sex?
Arabian horse, ponies, american miniature
Yes, females > 15 years
What are the surgical small colon disease?
84% simple obstructions
16% vascular or strangulating lesions
What are the clinical signs in case of small colon lesions? what are the key indicators for surgery?
Slow, unspecific clinical signs (also tenesmus,abdo dist , ↓ fecal production)and deterioration systemic status –> delayed intervention
- Reflux rare (up to 30% in cases of small colon strangulation)
- Key indicators surgery : abdo dist ++, ↑ peritoneal fluid, ↑ total prot and TNCC
What is the prognosis?
good to excellent short-term and long term prongosis
What are the simple obstructions?
- fecal impaction
- enterolithiasis
- fecaliths, phytobezoars, trichobezoars
- foreign body
- meconimum impaction
Fecal impaction what are the predisposing risk factors?
-poor dentition, poorquality hay, lack of water, parasite damage, lack ofexercise, submucosal edema, motility problems
- ! Horses with diarhea –> check small colon obstruction
- Fall and winter →↓ water consumption, change feed
- > 15y, American miniature horse, pony
What are the clinical anomalies when fecal impaction occurs?
CE: Abdo pain, ↓ manure, abdo dist, diarrhea, anorexia, fever, straining todefecate, depresion, leukopenia
- Abdominocenthesis: normal
- TRP impaction palpated (7587%), distention colon/caecum, edematousrectal mucosa, blood on manure
- SNG: occasionally reflux
Could you perform medical treatment in fecal impaction? what is the medical tx?
-Aggressive oral fluids (4L/46h),
gastrocolic reflex will increment colon motility
- Mineral oil (5- 10 ml/kg)
- Dioctyl sodium sulfosuccinate (50 mg/kg in 6L water)
- Magnesium sulfate (1g/Kg in 6L water) SID for 23 d
- IV fluids (23x maint)
- Flunixine meglumine (0,25 mg/kg IV TID or 1,1 BID)
- If sepsis, leukopenia, diarrhea: antibiotics, Polymixin B (20006000 IU/kg IV),endotoxin antiserum
- Enema: soap + hot water, sedation, buscopan (0,3 mg/kg IV),gravity flow!
When should go for surgery with fecal impaction?
↑ abdo pain, dist, changes in abdo fluid
What does the surgery consist for fecal impaction?
Small colon enema and extraluminal massage
What is the considerations of postop and prognosis for fecal impaction?
Low residue pelleted diet or grass and prognosis for medical and surgical is excellent
What is the major complication in small colon fecal impaction surgical procedure?
Salmonella spp in 43% and postop antibiotics may increase the risk
what is the % of small colon diseases encoutered due to enteroliths?
The small colon is the site of obstruction in 45% to 57% ofhorses with enteroliths, accounting for up to 35% of all smallcolon diseases
How do you perform the diagnosis enteroliths? what are the clinical signs?
CE: multiple episodes of mild colic < intermittent obstruction in large colon, then whenblocked in small colon: severe colic, abdo distention, leukopenia, worsening peritonealfluid →
! Pressure necrosis -> slight elevation in TP perit fluid –> surgery
Radiographs can be taken but the sensitivity is less good in small colon than transverse colon
What is the treatment enteroliths? describe
- Antimesenteric small colon enterotomy
- Retropulsion and removal through PF enterotomy: hose inserted via rectum or PF enterotomy
- water distention and massage
- Parainguinal incision: if located aborally and not possible to exteriorise via ventral midline
- Modified teniotomy: if not exteriorizable and located orally
Where else should you check for enteroliths?
large colon! ! 50% horses with small colon enteroliths have also enteroliths in large colon
Figure 38-2. Small colon enterolithiasis. Rupture through the mesenteric tenia at the site of obstruction with accumulation of feces in the small mesocolon.