Impactions

Question 1

Types of caecal impactions

Answer 1

Primary: acc of solid

Secondary: acc of liquid

May be combo of the 2

* may be no clinical or colic signs, if it also ivolves ileum is more of a surgical problem!!

Rupture is possible- often with no signif abd pain or systemic signs therefore monitoring is NB

Question 2

Pathogenesis of primary caecal impaction

Answer 2

Gradual development

Decr motility, the aboral movement slows or stops

Content: firm and dry (because the water reabs is still normal)

Normal defecation for some time as large colon was full and still functioning

Question 3

Primary caecal impaction: clinical signs

Answer 3

Repeats of mild colic

Decr appetite

Decr defecation

Variable manure

Decr peristaltic sounds on R

Normal CV

Rectal palpation: base is full! palpate on R in front of the pelvis

Question 4

Primary caecal impaction: treatment

Answer 4

Fasting

Fluid therapy: give water and salts every 2-3 hours orally and if reflux develops change to IV

Spasmoanalgetics

Epsom salts (magnesium sulfate) and other salt mixtures: principle: salt draws water into the lumen so horse can easily excrete

Surgery

Question 5

Secondary caecal impaction

Answer 5

Usually in sport horses when undergoing box rest from eg ortho surgery

Postop pain makes more difficult to recognise

Can be close to rupture by the time colic signs develop

Increased risk:

• <3 manure piles a day
• >1hr ortho surgery and a high dose of phenylbut

Question 6

Secondary caecal impaction clinical signs and options

Answer 6

Clinical signs similar to primary

Rectal palp: distened/ wall of caecum v tight, semi-liquid content

SURGERY

prognosis good if early and proper treatment

success rate similar for both types

Question 7

Caecal impaction differentials

Answer 7

Large colon impaction

R dors displacement of large colon

Caecal tympany

Mesenteric abscess- usually more cran, near the mesenteric route

Question 8

Large colon impaction aetiology

Answer 8

Frequent!

Feeding: poor quality hay and large amnt of straw

Dental: can’t chew the roughage

Decr water- esp in winter when water is cold

Obesity, lack of exercise

Old

*Rocking horse posture*

Question 9

Large colon impaction pathogenesis

Answer 9

Decr peristalsis

Normal H20 abs

Distended, full colon

Pain

Secondary tympany

Compression atrophy

Endotox, peritonitis (because the bact rich fluid is not going anywhere)

Rupture

Predilection sites: PELVIC FLEXURE

Ampulla at end of right dorsal colon

Question 10

Large colon impaction clinical signs

Answer 10

Mild to moderate colic signs

Rocking horse posture

Decr appetite

Approx normal vitals: PCV and TPP especially

Dehydration

Small, dark and firm faecal balls

Reduced sounds

Question 11

Large colon impaction diagnosis

Answer 11

Rectal palp: Pelvic flexure (I think btw the right ventral and dorsal colon?) localize in midline or slightly to the R, can even go into the pelvis

90degree torsion: when the dors and vetral colon are on the same level

Question 12

Large colon impaction differentials

Answer 12

Caecal impaction or tympany- diagnose by rectal palp and remember gas acc can be secondary to a primary obstruction or impaction

Large colon tympany

Enterolithiasis, bezoars

Mesenteric abscess

Eq grass sickness: innerv is lost, no peristalsis- content is normal just not moving- becomes dry and firm

Question 13

Large colon impaction treatment

Answer 13

Spasmolytics,analgesics, sedatives

Laxatives

Fluids via NG tube or IV

Fasting

Controlled exercise

Surgery

Question 14

Spasmolytics, analgesics and sedatives

Answer 14

Butylscopalamine

Flunixin, phenylbutazone

Xylazine, detomidine and but

Question 15

Laxatives (same as for primary caecal impaction)

Answer 15

Magnesium sulphate (epsom salts)

Salt mixtures e.g NaCl and Kcl in 4/5L of water throughout the day

Liquid paraffin- thought to decrease H2O abs from gut lumen, makes mucosa more slippery

Question 16

Fluid therapy

Answer 16

Start with NG tube!!

4-5 L of water + salt mixture every2-3 hrs

IV: increases water secretion into gut lumen by decreasing oncotic P

Question 17

Large colon impaction prognosis

Answer 17

good to excellent

Fair with surgery

Some possibel complication:

• Postop Dx
• Thrombophlebitis
• Incisional infection
• Peritonitis

Question 18

Small colon impaction

Answer 18

2 forms: simple and following Dx

How to tell if small colon? white taenia and haustra

*faecal balls covered by very thick yellowish mucus is very characteristic to small colon inf

Question 19

Small colon impaction types

Answer 19

Simple is very similar to L colon impaction

Following Dx:

• if Dx caused by inflamm- edema
• Large amnt of ingest enters small quickly
  
  • Initially Dx quickly switching to impaction

Question 20

Small colon impaction clinical signs

Answer 20

Mild colic

Good generally

Variable appetite

Reduced/no defecation

Very firm, dark, triangular or rectangular faecal balls

Reduced borborygmy

Distended abdomen: tympany in large colon

Question 21

Small colon impaction diagnosis

Answer 21

In mild to moderate cases only an arm-sized part of the small colon is affected, large amount of really firm faecal balls

Severe cases: just one very hard mass of faeces

Question 22

Small colon impaction Differentials

Answer 22

Complete small colon obstruction e.g enterolith or bezoar

Large colon impaction

Caecal impaction

Question 23

Small colon impaction treatment

Answer 23

Spasmoanalgetics

Salts

Rectal enema

Fluid therapy: oral or IV

Surgery