Equine Surgical Treatment Of Colic

Front 1

What are indications for colic surgery?

Back 1

- Severe continuous pain showing no or only short duration of improvement with analgesia.

- Pulse >60 bpm, progressively rising and weakening

- Progressive CVS collapse- mm injected- cyanotic.

- Increased abdominal distension.

- Rectal findings positive with acute abdominal disease.

- Progressive reduction in intestinal motility or continuous gastric reflux.

-Serosanguinous peritoneal fluid with protein >2.5 g/l and WBC over 10x109/l

Front 2

How is the horse positioned for colic surgery and what approach is used?

Back 2

Dorsal recumbency.

Generally a ventral midline laparotomy through the linea alba.

Front 3

Capacity of the equine stomach and can we exteriorise it? Indications for surgery of the stomach?

Back 3

15 litres and we cannot exteriorise it.

Impactions in adults like ingesting unsuitable dry feed, a motility issue or secondary to liver disease.

Pyloric stenosis in foals- acquired secondary to gastroduodenal ulcers or congenital.

Front 4

How can we treat a foal with pyloric stenosis?

Back 4

Pyloromyotomy- cut the muscle to release tension.

Bypass pylorus gastrojejunostomy.

Front 5

Where is the duodenum located? How long is it and can we exteriorise it?

Back 5

Attached to the right dorsal body wall by a short mesoduodenum preventing exteriorisation.

1m long.

Front 6

How long is the jejunum and can it be exteriorised?

Back 6

Jejunum is 15-30 m long with a long 50cm mesojejunum.

It can be exteriorised.

Front 7

How large is the ileum and what are features of it to tell it apart from other parts of the small intestines? Can we exteriorise it?

Back 7

70-80 cm ileum with a slightly thicker wall and distinctive antimesenteric bands, ileocaecal fold--> dorsal taenia of caecum.

Cannot exteriorise the distal ileum and ileocaecal junction.

Front 8

What is common complication after small intestinal surgery? How can we prevent this from happening?

Back 8

Ileus.

Prevent this from happening by gentle tissue handling.

Front 9

What types of small intestinal lesion do not require surgical resection? Which ones need resection?

Back 9

Non strangulating lesions of the small intestine.

Strangulation lesions require transection.

Front 10

Aetiology of a non strangulating small intestinal lesion leading to colic?

Back 10

Ascarids in young animals.

Tapeworm in the ileocaecal orifice.

Unsuitable feed.

Primary motility problem.

Muscular hypertrophy.

Front 11

Treatment for a non strangulating small intestinal lesion causing a surgical colic? Prognosis?

Back 11

Decompress at surgery and enterotomy only if necessary.

Prognosis: very good.

Front 12

Signs of tumors leading to non strangulating SI colic? Name the most common SI tumor other symptoms that occur with it? Treat? Prognosis?

Back 12

Thickening of intestinal wall leads to partial/ complete obstruction of gut wall leading to altered motility.

Lymphosarcoma accompanied by signs of weight loss.

Treatment: Resection but often multifocal leaving this impossible.

Prognosis: poor.

Front 13

Aetiology of anterior enteritis? Signs? Treament?Prognosis?

Back 13

Unknown: clostridia/salmonella/diet.

Get mark distension of the proximal SI and stomach which resembles a surgical colic.

Treatment: Medical- repeated nasogastric intubation.

Surgery: decompression.

Prognosis: 50-70% survival.

Front 14

What is the general approach to a strangulating SI lesion?

Back 14

1) Identify the cause of the strangulation such as pedunculated lipoma, intussusception, SI volvulus.

2) Reduce strangulation.

3) Assess gut viability.

4) Decompress, resect and anastomose if gut non viable.

Front 15

How do we assess the viability of a portion of gut?

Back 15

Viable gut has active haemorrhage when nicked, peristalsis and pulses.

Compromised: Avulsed vessels, haemorrhagic, red.

Non viable: thin walled, black, grey or green colour.

Front 16

Prognosis for SI strangulating lesion depends on?

Back 16

Length of gut affected, duration of obstruction and consequence of CVS/endotoxaemic status of horse.

60-85%

Front 17

What is the most common cause of SI strangulation and what animals does it usually occur in?

Back 17

Pedunculated lipoma which mainly occurs in mature/obese animals.

Front 18

Treatment of a pedunculated lipoma SI strangulation?

Back 18

Resect the lipoma, pedicle and non viable gut.

Front 19

Aetiology of SI volvulus?Signs? Prognosis?

Back 19

Jejunum rotates about its attachment in dorsal abdomen at cranial mesenteric arterial root.

Signs SEVERE PAIN.

Prognosis poor.

Front 20

Aetiology of intussuception? Treatment?

Back 20

Young animals more common jejuno-jejunal area.

Proximal intussusceptum into distal intusscuscipiens leading to obstruction. then strangulation as more gut entrapped and artery supply drawn in.

Treat: Reduce.

Assess viability +/- resection and anastomosis.

Front 21

What is the cause of thromboembolic colic?

Back 21

Migration of Strongylus vulgaris larvae.

Front 22

Types of SI entrapment leading to colic surgery?

Back 22

Epiploic foramen entrapment.

Inguinal/scrotal hernia.

Herniation through a mesenteric rent.

Gastro-splenic ligament.

Umbilical hernia.

Diaphragmatic hernia.

Front 23

What part of the caecum is the only part we can exteriorise? What do we use the caecum to find?

Back 23

The apex.

Dorsal band--> ileocaecal fold.

Lateral band- ventral colon.

Front 24

Cause of primary caecal impaction? Secondary?

Back 24

Primary caecal impaction--> unsuitable food.

Secondary--> Motility disorder.

Hostipalized patient, repeated GA, sedation,painful condition, limited movement.

Front 25

How do we surgically resolve caecal impaction?

Back 25

Apical typholotomy +/- a caecal bypass.

Front 26

Types of caecal intussuception?

Back 26

Caecocaecal.

Caecocolic.

Front 27

Describe the course of the large colon from the caecum to the anus?

Back 27

Caecum--> RVC--> LVC --> LDC--> RDC--> Transverse colon--> small colon.

Front 28

What parts of the large colon can we not exteriorise?

Back 28

RVC, RDC and caecal base as attached to the body wall!!!

Front 29

Causes of large colon displacements?

Back 29

Gaseous distension.

Transient motility disorders.

Sudden diet changes.

Parturition.

Idiopathic.

Front 30

What happens with a left dorsal displacement of the large colon? Treat?

Back 30

Colon becomes entraped between dorsal aspect of spleen and nephrosplenic ligament adjacent to the left kidney.

Treat with surgery and reduction of displacement.

Front 31

What can we do prior to colonic surgery ?

Back 31

Relieve distension/impaction.

This aids manipulation, allows repositioning in abdomen, improves post operative motility.

Front 32

What occurs with a right dorsal displacement?

Back 32

The left colon migrates around the body of the caecum clockwise or anticlockwise.

Front 33

Indications for surgery with a RDD? Treat? Prognosis?

Back 33

Unremitting pain, increasing distension, deterioration in CV status.

Treat: reduce displacement, dump colon, replace.

Can do a colopexy to abdominal wall if colon displacement recurs eg in breeding mares.

Prognosis good.

Front 34

Complications of RDD?

Back 34

Progress to colonic volvulus/ torsion.

Front 35

Signs of colonic volvulus/torsion? Treat?

Back 35

180-360 torsion around caecolic junction.

Extremely painful, rapid deterioration due to massive endotoxaemia.

Treat QUICKLY.

Colonic resection.

Front 36

Where do enteroliths tend to lodge? Treatment?

Back 36

Narrow transverse colon.

Treat surgically remove via enterotomy.

Front 37

Aetiology of atresia coli? Diagnose? Treat?

Back 37

Heritable congenital condition of foals results in atresia of segment of colon and or atresia ani.

Diagnose by contrast radiography.

Treat: surgical correction if segment not to long.

Front 38

Causes of small colon impaction? Treatment?

Back 38

Focal enteroliths.

Primary motility issue.

Intramural haemorrhage.

Manual decompression or enterotomy.

Front 39

How do we grade rectal prolapses? Which carry worst prognosis? Treatment?

Back 39

1-4

3-4 guarded prognosis as mesorectum tears.

Treat: mild: clean, resect affected muscosa and replace providing seromuscular layer is intact.

25-30 prolapse more aggressive surgery.

Front 40

When do rectal tears usually occur and where? How do you diagnose?

Back 40

Occur during rectal.

Usually occur in the 10 and 2 o'clock position at the attachment of mesocolon.

Blood on rectal glove to diagnose.

Front 41

How do we grade rectal tears?

Back 41

1-4

1: Mucosa only involved.

Grade 2: Muscularis only

Grade 3: Mucosa and muscularis.

Grade 4 : all layers and life threatening.

Front 42

Most important steps to take if you get a rectal tear?

Back 42

1) ID early.

2) Tell owner.

3) Institute first aid.

4) Refer.

Front 43

First aid for a rectal tear?

Back 43

1) Sedate.

2) Epidural or large volume of local per rectum.

3) Careful evacuation.

4) Packing rectum with lubed noted tights etc.

5) Broad spectrum A/B

6) NSAID

7) Referral for surgery if severe- colostomy to bypass the rectum or an indwelling rectal liner.

Front 44

Prognosis for rectal tears?

Back 44

1-2: good to fair.

3: guarded.

4: POOR

Front 45

Complications of colic surgery?

Back 45

1) Repeat episodes of colic.

2) Continued endotoxaemia/dehydration.

3) Ileus.

4) Incisional drainage/ infection/ herniation.

5) Adhesions.