Surgery Of The Colon Flashcards by Chloe Tredinnick

3 divisions of the colon?

Ascending
Transverse
Descending

How well did you know this?

Not at all

Perfectly

Which side of the abdo is the ascending colon found?

RHS

How well did you know this?

Not at all

Perfectly

What does the ascending colon run cranial to?

Right colic flexure

How well did you know this?

Not at all

Perfectly

Which direction does the transverse colon run?

R –> L

How well did you know this?

Not at all

Perfectly

Where does the transverse colon run to on the LHS?

Left colic flexure

How well did you know this?

Not at all

Perfectly

What is the arterial supply of the colon?

Cranial abdominal branches of the aorta

How well did you know this?

Not at all

Perfectly

What branch supplies the ascending colon?

ileocolic

How well did you know this?

Not at all

Perfectly

What branch supplies the transverse colon?

Right colic

How well did you know this?

Not at all

Perfectly

What branch supplies the proximal descending colon?

Middle colic

How well did you know this?

Not at all

Perfectly

What do the colon supply arteries then divide and branch into?

Short irregular vasa recta

How well did you know this?

Not at all

Perfectly

Which border do the arteries enter?

Mesenteric

How well did you know this?

Not at all

Perfectly

The distal portion of the descending colon is supplied initially by the A) branch of the caudal abdominal branches of the aorta and then more distally by the B) artery which run similarly along the mesenteric border.

A) left colic
B) cranial rectal

How well did you know this?

Not at all

Perfectly

Due to the particular longitudinal course of the blood simply to the colon, when considering a segmental resection of the colon - where should this be done?

Level of the vasa recta

How well did you know this?

Not at all

Perfectly

What is the ascending colon attached to? (2)

Mesocolon
Mesoduodenum

How well did you know this?

Not at all

Perfectly

Why is the ascending colon difficult to visualise/exteriorise in surgery?

Attachments are short - 2-3cm

How well did you know this?

Not at all

Perfectly

What is revealed in the colonic manoeuvre?

L sublumbar fossa

How well did you know this?

Not at all

Perfectly

What is lifts in the colonic manoeurve?

Descending colon

How well did you know this?

Not at all

Perfectly

What are reabsorbed in the colon? (4)

Water
Sodium
Chloride
Short chain fatty acid

How well did you know this?

Not at all

Perfectly

What is secreted in the colon? (2)

Bicarbonate
Mucous

How well did you know this?

Not at all

Perfectly

What are the reasons for increased complications for colon surgery? (5)

High bacterial load
Short mesenteric attachments
Damage to mesenteric blood supply
Infect
Surgeon familiarity

How well did you know this?

Not at all

Perfectly

Peri-operative natibacterial prophylaxis for colon surgery?

Cefuroxime (20 mg/kg q90m from induction to abdominal closure) and metronidazole (10 mg/kg q8h) are often used in combination.

How well did you know this?

Not at all

Perfectly

Use of post op antibiotics in colon surgery?

However, following uncomplicated colonic surgery there is no indication for postoperative use of antibiotics and with an increasing risk of bacterial resistance, veterinary surgeons have responsibilities to limit the use of antibacterial medication.

How well did you know this?

Not at all

Perfectly

What is the term for caecal resection?

Thyhlectomy

How well did you know this?

Not at all

Perfectly

When is a typhlectomy indicated? (6)

Perforation
Caecal inversion
Impaction
Inversion
Severe thyphlitits
Neoplasia

How well did you know this?

Not at all

Perfectly

What should try to be preserved in a thyplectomy?

Ileo-colic junction

Prior to resection, what needs to be done with the caecal when inverted?

Evert it!

What suturing is done for a typhlectomy? Include material?

Following resection between two sets of clamps, a Parker-Kerr suture pattern can be used to oversew the remaining clamp, inverting the edges of the incision. An inverting Lembert pattern can then be used to reinforce the incision. 1.5-2 metric synthetic monofilament absorbable suture material is appropriate

If using a stapler, what stapler height should be used for typhlectomy?

2mm

What is done during a typhlectomy?

Following dissection of the ileocaecal fold, atraumatic clamps such as Doyen bowl forceps are placed across the base of the caecum

What type of biopsy if preferred for colon?

Excisional

Colotomy: How to SURGICALLY prepare the area? (2)

- Isolate with lap swabs or sponges - The contents of the identified section should be moved proximally and distally to further minimise risk of contamination

Where is the colotomy incision made?

Antimesenteric border

How to facilitate minimal handling with colotomy?

A full thickness monofilament stay suture can be placed through the colon at the proposed site of biopsy with an elliptical incision then made around this stay suture.

How to suture colotomy site: - Prep/ - Material - Pattern

- cleaned before being sutured - monofilament absorbable material (polydioxanone or polyglyconate are good choices) -simple continuous or simple interrupted pattern. It is possible to add an inverting layer (Lembert suture).

Following colon suture; what is done before abdo closure? (2)

- Clean colon site - Abdo flush (can omentalise - not not needed)

Indications for colectomy (5)

Neoplasia Megacolon Perforation Trauma Chronic Intussusception.

Most common condition + species for colon surgery?

megacolon - cat

What is a subtotal colectomy?

Colon resection WITHOUT the removal of ileocaecal valvce

What is a total colectomy?

Removal of colon AND ileocecal valve

Which part of the colon remains with a total colectomy?

Distal - unless pelvic approach made

Where is the colectomy started with subtotal colectomy?

1-2cm distal to ileocolic junction

Where is total colectomy started?

1-2cm proximal to ileocolic junction

How to approach colectomy?

The appropriate area of colon is identified and isolated from the abdomen using moistened laparotomy swabs or sponges. The contents are milked proximally and distally before Doyen bowel clamps are placed across the colon about 3 cm away from each of the proposed incision sites.

What forceps can be placed across the portion of colon to be resected and the transection incision made adjacent to these before the portion of resected colon is removed?

Rochester-Carmalt

What is ligated with colectomy?

INDIVIDUAL vasa recta

When is segmental colectomy performed?

Intra or extra luminal mass present

Suture material for colectomy?

Monofilament (PDS or polyglyconate) 1.5-2m

If an approach to the pelvic colon is needed; what needs to be performed?

pelvic flap

How to suture colectomy?

- Simple interrupted sutures = initially laced 180° apart at mesenteric and antimesenteric borders Side: sutured using either a simple continuous or simple interrupted appositional suture pattern.

What layer has to be included in colectomy closure?

Submucosa

After leak testing colectomy; what needs to be applied?

Omental patch - interrupted sutures

How can staples be used for colectomy? (2)

Transrectal Transcaecal

What is used in colopexy?

Descending colon to left abdo wall

When might colopexy be used? (2)

Rectal prolapse Perineal hernia

What is the only acceptable technique of colopexy?

Appositional technique

How is an appositional colopexy performed?

Interrupted or simple continuous monofilament sutures (polypropylene, polydioxanone and polyglyconate are suitable materials) are placed through the wall of the descending colon (including the submucosa) and then through the left lateral abdominal wall musculature.

Why is incisional colopexy not used?

RISK - colonic perforation

What should be given post op from a colopexy?

Stool softener - reduce straining/risk of breakdown

What is megacolon? (2)

- Hypomotility - Increase colon diameter

What are the 4 underlying types of megacolon?

Idiopathic Mechanical Neuropathic Endocrine

What does congenital megacolon occur as a result of?

Failure or abnormality in the development of the neural plexuses that supply the distal colon

How common is congenital megacolon?

Very rare

What is a common identified prequel to megacolon in cats?

Stenosis of the pelvic canal, secondary to pelvic fracture malunion

With Stenosis of the pelvic canal, secondary to pelvic fracture malunion. When is surgery advised?

Narrowing <45%

What surgery has been shown to cause acquired megacolon?

OVH

What can cause mechanical obstruction causing acquired megacolon? (4)

- Neoplasia - Stenosis of pelvic canal - Prostatomegaly - Stricture

What can cause functional obstruction causing acquired megacolon? (4)

HypoT4 HypoK Dysautonomia Ileus Sacral spinal cord defmormities

Define obstipation

Inability to pass faeces

What % of megacolon is cats are idiopathic?

Signs of megacolon? (7)

- Constipation - Obstipation - anorexia - V+ - weight loss - dehydration - Urinary obstruct (2ry to space occupying)

Diagnosis of megacolon is made how (3)

- CE - Rectal exam - Lateral x ray

What is an enlagred colon on lateral xray?

If the colonic diameter exceeds 1.5 times the length of the seventh lumbar vertebra, megacolon is confirmed.

When can megacolon be treated medically? What can be used? (3)

Early cases - Soften/laxative, dietary fibre, prokinetic e.g. cisapride

What is the issue of using partial colectomy for megacolon?(3)

Leaves damaged, atonic, albeit narrowed colon in situ

What % of intestinal tumours in dogs are colonic?

Most common tumour of colon in dogs?

Addenocarcinoma

Most common neoplasia of colon in cats? (2)

Lymphoma Adenocarcinoma

colonic tumours in dogs? (8)

Adenocarcinoma Lymphosarcoma GI stromal tumour Leiomyocarcoma Plasmacytoma MCT Neuroendocrine tumour Lymphoma

Clinical sings of colon neoplasia? (5)

- D+ - V+ - An/hyporexia - Constipation + haematochezia - Tenesmus

Surgical resection margins for colon tumour?

5-8cm

Which tumour cannot be surgically removed?

Lymphoma

The mean survival time for dogs following resection of a colorectal adenocarcinoma is reported to be between?

6-22mo

In cats, the mean survival time is between 9 and 20 weeks with colon tumours. But how many were found to be metastatic at surgery?

75%+

How common are colon torsions?

Rare

Breeds for colon torsion?

Medium - large breed

T or F Most cases of colon torsion include the ileocecocolic junction

True

Following volvulus, the what artery is occluded or restricted leading to a reduction in perfusion and potential ischemia of the small intestines, caecum and colon.

cranial mesenteric

Colon Torsion & Colonic/Caecocolic Volvulus Clinical signs? (6)

Dehydration Abdo distension Tenesmuc Poor peripheral pulse Tachycardia Low temp

What is seen on xray with Colon Torsion & Colonic/Caecocolic Volvulus?

Large gas filled distended bowel loops (esp in caudal abdo)

Treatment of Colon Torsion & Colonic/Caecocolic Volvulus?

- Ex lap (Stabilise first!)

It is sometimes necessary to deflate the distended section of colon with a torsion; how is this done? (2)

This can be done using a 16- or 18-gauge needle and suction.

What does prognosis of colonic torsion depend on?

Ischaemic damage

Mortality with colonic torsion?

50%

What is done during ex alp with colonic torsion? (2)

Colectomy Colopexy

Surgery Of The Colon Flashcards

(94 cards)