Bovine abdominal surgery 4

Question 1

small intestinal lesions
* Right flank approach
- standing vs GA?

Answer 1

• Standing vs GA depends on degree of pain cow is in & whether able to stand
• In addition, intra-operative pain from manipulation of mesentery may cause cow to go down
• If doing recumbent, GA is preferable to sedation to prevent aspiration pneumonia

Question 2

Small intestinal accidents
- types?
- is it easy to ddx pre-operatively?

Answer 2

o Non strangulating (simple and functional) vs strangulating
> Simple obstruction: enterolith or accumulation of hair and debris
> Functional: ileus, often associated with inflammation and infection
o Difficult to ddx an obstruction pre-operatively vs functional disorder eg enteritis

Question 3

Clinical signs of strangulating obstruction
- what parts of intestines affected? consequence?

Answer 3

o Commonly distal jejunum and ileum affected, so fluid sequestrates in proximal intestine
o Results in dehydration, and because outflow of abomasal fluid rich in HCl is impeded,
hypochloremic metabolic alkalosis normally ensues
* Also hypokalemic from lack of dietary intake

Question 4

Clinical signs of strangulating obstruction
- pain and signs?
- tension on what structure?
- bowel / abdominal distension?

Answer 4

• Severe abdominal pain – stretching out, treading, kicking at abdomen, recumbency
• Tension on mesentery
• Bowel distension proximal to lesion, low and bilateral abdominal distension, succussion shows fluid wave

Question 5

Clinical signs of strangulating obstruction
- fecal signs? what to measure in abdominal fluid?
- important diagnostic exams?

Answer 5

o Scant manure, maybe melena from sloughing of devitalized intestine
o Abdominal fluid analysis if can be obtained – measure cells and lactate
* Ultrasound and rectal examination

Question 6

Duodenal outflow obstruction
- causes? does presentation differ with cause?

Answer 6

• Foreign bodies, intraluminal or extraluminal masses, adhesions in sigmoid flexure, duodenal sigmoid flexure volvulus
• Similiarities between cases regardless of cause

Question 7

Duodenal outflow obstruction
- common clinical signs

Answer 7

o Common clinical signs: anorexia, decreased milk and fecal production, tachycardia, varying degrees of depression, decreased ruminal contractions
o Also, abdominal distension, colic, scant feces, ruminal distension

Question 8

Duodenal outflow obstruction
- fluid & electrolyte disturbances?

Answer 8

• More severe fluid & electrolyte disturbances than cows with abomasal volvulus
• Dehydration, hyponatremia, hypokalemia, hypochloremia, hyperphosphatemia, hyperglycemia, hyperproteinemia, metabolic alkalosis, elevated anion gap

Question 9

Duodenal outflow obstruction
- characteristic distension pattern? effect on abomasum?

Answer 9

• Characteristic is distension of the cranial portion of the duodenum with a flaccid descending duodenum
• Abomasum may be dilated and dorsally displaced

Question 10

Duodenal outflow obstruction
- treatment

Answer 10

o Treatment: removal of any obstruction
o Duodenal bypass if necessary – cranial part anastomosed to descending duodenum in side to side manner

Question 11

Duodenal outflow obstruction
- should be considered if what type of DA? what should we do?

Answer 11

o Should be considered if RDA found without volvulus
> Reexplore cow for definitive treatment if the signs were treated with omentopexy and fluid and electrolyte disturbances progress

Question 12

Intussusception
- wut dis
- anatomic location where most common
- untreated cattle outcome?

Answer 12

• Invagination of a portion of intestine into the lumen of adjacent bowel
• Drags mesentery and blood vessels with it, creating strangulating obstruction
• Most commonly small intestinal, also cecocolic or ileocolic
• Untreated cattle die 5-8 days after onset of clinical signs

Question 13

Intussusception clinical signs, U/S signs

Answer 13

• Cattle exhibit mild to moderate pain, anorexic, lethargic, tachycardic, melena
• Rectal and ultrasound show distended small intestine

Question 14

Intussusception - surgical approach - how to find location

Answer 14

• Right paralumbar fossa celiotomy, more thorough if GA
• Cecum identified, exteriorized & traced to ileum, leads to jejunum

Question 15

Intussusception
- how to correct surgically? prognosis?

Answer 15

• Intussusceptum identified but unsafe to reduce
• Resection and anastomosis: one layer inverting
  continuous pattern, such as Lembert
• End – to – end anastomosis
  > Ligate vessels close to bowel
  > No serosa at mesentery Þ rotate bowel 30o
  > 2.0 absorbable suture
  > Close mesenteric defect
  > Lavage
• Post op survival of 40%

Question 16

Intestinal volvulus
- whats this? where is common?

Answer 16

• Twisting of a segment of bowel upon itself
• Long mesentery of distal jejunum and ileum makes this more prone to volvulus

Question 17

Intestinal volvulus
- surgical approach? position? how do we find it? prognosis?

Answer 17

• Right paralumbar fossa celiotomy
• Standing or recumbent
• In situ feel for tight bands or masses
• Proximal intestine gas distended
• Bowel is untwisted & brought to incision
• Run hand straight up to root of mesentery
• Prognosis depends on duration of obstruction and viability of intestine
• Resection and anastomosis if necessary

Question 18

Torsion of the mesenteric root
- what is this? signs? what should we do?

Answer 18

• Volvulus of the entire small intestinal tract
• Profound pain
• Bilateral abdominal distension, tachycardic, and tachypneic
• Tight bands and distended viscera on palpation per rectum
• Prompt surgical intervention

Question 19

Torsion of the mesenteric root
- how to correct? surgical position? careful about what during surgery? prognosis?

Answer 19

• By following the mesenteric root the twist is identified and corrected
• Standing or lateral recumbency – surgeons preference
• Untwisting such a large amount of intestine can lead to endotoxic shock
• Rapid progression of signs makes the prognosis grave

Question 20

Herniation
- common tissues involved? clinical signs? how to correct?

Answer 20

• Herniation – omental bursa, mesenteric rents, persistent entrapping umbilical structures, epiploic foramen entrapment, scrotum
• Clinical signs similar to those of cow with intussusception with moderate abdominal pain
• Right paralumbar fossa celiotomy – if entrapping band, should be transected blindly with scissors

Question 21

Jejunal hemorrhage syndrome
- another name
- when do we see it?
- sometimes what serious outcome?
- consistnet finding?
- case fatality?

Answer 21

o Also called hemorrhagic bowel syndrome
o Presents in early lactation
o Sometimes acute death
o Consistent finding of intraluminal blood clot
o Case fatality rate of 85%

Question 22

Jejunal hemorrhage syndrome
- can cows be saved?
- treatments?
- what makes prognosis worse?
- likely pathogen?

Answer 22

o Early diagnosis and immediate intervention may save some cows
o Medical therapy, blood transfusion, fluid therapy, anti-inflammatory and analgesic,
antimicrobials
o Manual clot breakdown in surgery
o Multiple affected segments worsens prognosis o Likely from Clostridium perfringens Type A

Question 23

Cecal Dilation & Volvulus
- etiology

Answer 23

• Unclear ~ abomasal problem
• Decreased exercise
• High concentrate/low fiber rations
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  o Causes are not clear: hypocalcemia, diets rich in starch, abrupt increase in concentration of volatile fatty acids

Question 24

cecal dilation vs dislocation vs torsion vs volvulus

Answer 24

o Cecal dilation is distension of cecum without a twist
o Rotation along its long axis is a torsion, rotation in the area of the ileocecocolic junction is a volvulus. The term dislocation encompasses torsion, volvulus, twist or retroflexion

Question 25

what is cecal volvulus?

Answer 25

Volvulus: cecum + proximal & spiral loops of ascending colon > twist

Question 26

Cecal Torsion - what is this, where does it occur?

Answer 26

• Rotation along the axis of the cecum > occurs right at the ileocecal fold

Question 27

cecal dilation clinical signs

Answer 27

• Mild signs:
  > decreased appetite,
  > decreased milk production,
  > decreased fecal output,
  > ± abdominal distension
• Ping in R paralumbar fossa
  o More caudal in abdomen than RDA
• Gas-distended tubular viscus in pelvis (apex)!
• Ketonuria, chronic case > metabolic alkalosis

Question 28

• Clinical signs – Cecal Volvulus

Answer 28

More severe signs
* Anorexia & sudden drop in milk
production
* abdominal pain & distention & no feces
* increased HR, dehydration
* ping in R paralumbar fossa & fluid on succussion

Question 29

Cecal Dilation & Volvulus
- what do we feel on palpation per rectum?

Answer 29

• SI distention
• Body of cecum palpated, apex rotated forward
  o On rectal examination, body of cecum not apex can be palpated

Question 30

Cecal Dilation & Volvulus
- blood work?

Answer 30

• Hemoconcentration
• Cl down, K down, metabolic alkalosis > metabolic acidosis > duodenal obstruction or back-up of abomasal contents

Question 31

cecal dilation medical treatment

Answer 31

• correction of ketosis & electrolytes imbalance
• diet modification
• increase exercise
• parasympatomimetics

Question 32

cecal volvulus medical treatment

Answer 32

• IV fluids prior SX

Question 33

surgical treatment for Cecal Dilation & Volvulus? when apropriate? what approach?

Answer 33

• For dilation if not responsive to medical Tx
• A must for volvulus/torsion
• R-flank celiotomy
  > cecal decompression
  => Gas: needle
  => Fluid: typhlotomy

Question 34

Cecal Dilation & Volvulus
- typhlotomy - how to perform?

Answer 34

o Right flank approach, ideally standing
o If simply dilated, cecal apex found in pelvic inlet
o Apex directed cranially if retroflexed
o Dislocations are carefully corrected intraabdominally
 Cecum and PLAC are exteriorised
 May need to do typhlotomy prior to untwisting
* Apex isolated, and typhlotomy performed at most ventral aspect
* Lavaged with saline and closed with double inverting 2-0 absorbale suture pattern
 Cecum returned to abdomen, and if refilled, a second typhlotomy is performed

Question 35

when is typhlotomy indicated?

Answer 35

• Recurrent dilation
• Cecum remains compromised
• Cecal infarction
• Ileocecocolic junction needs to be unaffected!
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  o Medical treatment if cecal dilation if normal or mildly affected general condition
  o If unsuccessful after 24 h, or condition is more profound, typhlotomy is indicated

Question 36

Cecal Dilation & Volvulus: Cecal amputation only indicated if

Answer 36

if recurrence or devitalization of cecal wall

Question 37

Typhlotomy post op care?

Answer 37

o Post-operatively, motility agents, such as bethanecol or neostigmine
o Antimicrobials due to contamination
o Analgesics
o IV or oral rehydration
o Restricted diet for 48 hours

Question 38

typhlotomy complications? recurrence? long term survival?

Answer 38

o Complications: septic peritonitis and persistent motility disorder
o Recurrence of 10-20%
o Long term survival of 70%

Question 39

Amputation of cecum - when is it appropriate? how to perform?

Answer 39

o If recurrence or devitalization of cecal wall
o Cecum exteriorised and emptied via typhlotomy
o Ileocecocolic ligament is blocked with lidocaine
o Cecal branches of cecal artery and vein are ligated close to attachment of ligament to cecum to preserve blood supply to ileum
o Intestinal clamps placed across cecum prior to transection
o Closure with 2 inverting seromuscular suture patterns with 2-0 absorbable suture material
o Complete typhlectomy has been reported with ileocolic anastomosis