Rectal tear and Prolapse HORSE Flashcards Preview

EXAM 3 FINAL > Rectal tear and Prolapse HORSE > Flashcards

Flashcards in Rectal tear and Prolapse HORSE Deck (54)
Loading flashcards...
1
Q

Where do rectal tears in horses most commonly appear? WHY?

A
  • Dorsal aspect of the rectum and longitudinally
  • right at the peritoneal reflection

*that is where the circular muscle layer becomes thinner

2
Q

If related to dystocia, where are rectal tears most commonly seen in horses?

A

-Ventrally

1-30 cm long

3
Q

What are the predisposing factors for rectal tears in horses?

A
  • Arabian and Miniature horses
  • Mares
  • older >9yo
  • other: Fractious horses and previous tears
4
Q

What is the most common cause for rectal tears in horses?

A

Transrectal palpation

For:

  • colic
  • reproductive purposes

Tears as wall contrast around hand

5
Q

T/F: the increasing use of US has decreased the incidence of rectal tears

A

TRUE

6
Q

How can you prevent rectal tears?

A
  • Copious lubrication
  • cleaning out rectum of all feces
  • relax arm when horse strains/peristalsis
  • sedation and antispasmodic
7
Q

What can be used to chemical and physically restrain a horses for a rectal exam?

A
  • xylazine

- butorphanol

8
Q

What drug can be used to decrease rectal pressure in a horse?

A

BUSCOPAN
(N-butylscopolammonium bromide)

  • 0.3mg/kg IV
  • decreases rectal pressure by 70%
9
Q

T/F: lidocaine enemas can decrease rectal pressure

A

False they cannot

10
Q

Why should a parasympatholytic drug not be given before doing a PE?
-example

A

It can increase HR

BUSCOPAN
-decreases rectal pressure

11
Q

How are Rectal tears classified?

A

Grade 1 (mucosa and sub mucosa torn)

Grade 2. (Muscle layer torn)

  • mucosa and sub mucosa intact
  • rare/incidental finding/impaction
Grade 3 (Mucosa, submucosa, muscularis torn)
-serosa intact

Grade 4 (complete tear)

12
Q

How do you distinguish between grade 3A and grade 3B rectal tears?

A

3A - only serosa intact

3B - mesorectum invovled, more dorsal (12oclock),

13
Q

What are the clinical signs or a horse with a rectal tear?

A

1) On palpation:
- sudden release of resistance
- FRESH blood (except grade 2)
- direct palpation of viscera (grade 4)

2) Straining to deficate

3) Peritonitis
-grade 3 and 4
-abdominocentesis
——-WBC >50 000 within 30 min
-Retroperitoneal abscess if caudal to reflection

14
Q

Why do you not see blood on palpation of a grade 2 rectal tear?

A

Because MUCOSA and SUBMUCSA are still intact

Only the muscularis is torn!!!!

15
Q

Why would you get peritonitis with grade 3 rectal tear?

A

You only have the serosa

16
Q

What is the normal value for WBC within the peritoneal cavity?

A

between 5 and 10 000 WBC

17
Q

Why do some horses get depressed with rectal tears?

A

Endotoxemia (within 2 hours)

-Horses are extremely sensitive to LPS in the blood stream

18
Q

What are the clinical signs of endotoxemia?

A
  • lucopenia
  • increased HR
  • toxic line
19
Q

T/F: Endotoxemia will happen with all rectal tears except grade 2

A

True

  • all rectal tears that bleed
  • grade 2 doesn’t bleed because only the muscularis is torn
20
Q

Why do you not get endotoxemia with grade 2 rectal tears?

A

Because grade 2 have an INTACT mucosal barrier

21
Q

T/F: wait and see may be deemed as negligence?

A

TRUE

22
Q

What can be used to STOP straining in a horse rectal tear case?

A
  • assess severity (1,3,4 grade)
  • Xylazine (0.17mg/kg) + lidocaine (0.2mg/kg)
  • Onset 5’ duration 5 hrs
  • epidural (between c1 and c2)
  • Hanging drop technique
23
Q

What can diagnostic tools can be done to assess the Severeity of a rectal tear in a horse?

A
  • speculum
  • endoscopy
  • ABDOMINOCENTESIS (for presence of peritonitis)
  • CBC (ET)
  • CHEM (ET)
24
Q

What first aid measures should be taken for a horse with a rectal tear?

A
  • sedation and severity examination
  • Braod spectrum Abx + NSAIDs
  • Fluid therapy (ET)
  • Rectal tampon
  • Prompt referral**
25
Q

How far oral should a rectal tampon be placed?

A

At least 10cm oral to the lesion
-insert partially filled and then fill the rest once inside

*refer with purse string or towel clamp

26
Q

how would you treat a rectal tear in a horse CONSERVATIVELY?

A

1) Antibiotics + NSAIDs
2) Fluid replacement (PO,IV) as needed

3) Laxatives + low bulk Diet (pellets/ mash etc..)
—-Oral fluids + MgSO4 (1g/kg)
—-Mineral oil

4) Daily removal of feces from rectum
—Q1-2hrs for 5 days
—Q6 then until healed (9-21 days)

PREVENT impaction of feces onto the tear!!!!

27
Q

What broad spectrum antibiotics would you consider for treating a rectal tear conservatively?

A

1) Penicillin for:
—Gram +
—Anaerobes

2) Gentamycin:
—GRAM -

3)Metronidozole:
—anaerobes (betalactamase producing/resistant)
-apparently not good for Cali horses (raging colitis)

28
Q

How would you treat a Grade 1 rectal tear in a HORSe?

A

CONSERVATIVE management

  • rarely require Sx
  • heals from remaining SM (~10days)
  • Good prognosis with CM 90% survival
29
Q

How would you treat a grade 2 rectal tear in a horse?

A

CONSERVATIVE management

  • incidental finding
  • dietary changes aimed to soften feces

Unless there is chronic impaction in diverticulum, these horses need to be euthanized

30
Q

How would you treat a grade 3 rectal tear in a horse?

A

1) Conservative management (40-70% survival rate)
- labor intensive (epidural catheter, regular manual evacuation, abdominal lavage)

PREVENT progression to grade 4

31
Q

When do you consider surgical management for rectal tears in horses?

A

GRADE 3/4
-combine with abdominal lavage and drain (standing, ventral and midline celiotomy)

  • Different techniques depending on:
    1) tear location
    2) settings and finances
    3) Case-based
32
Q

What is the survival rate of a horse with peritonitis?

A

50%

33
Q

What surgical technique would you use for a rectal tear that is close to the anus ?

A

Direct suture repair
-epidural—>Pneumorectum—>+ room
-clean lumen and tear with moistened gauze
-debride
-Externl anal sphincter can be incised @ dorsal comminuted
-retraction with stay sutures
—@12,3,6,9 o’clock

Not reachable through midline
-EASY and INEXPENSIVE

  • close in direction of less tension (TRANSVERSLY)
  • bites <1.5cm
  • sutures placed subserosally
34
Q

How would you close a direct suture repair of a rectal tear (close to anus)?

A
Close in direction of LESS tension
-usually TRANSVERSLY
-suture bites <1.5cm 
(To avoid lumen reduction
-Subserosal suture placement
35
Q

What are the 3 ways to repair a rectal tear close to the anus?

A

1) speculum + long handle instrubments
2) Non-visual direct suturing
3) Prolapse tear through anus

Any of these can be combined with bypass procedure

36
Q

T/F: in a direct suture repair of a rectal tear near the anus, you want to use gloves

A

FaLSE

-want to have bear hand for better feeling

37
Q

What surgical repair would you recommend for a post foaling mare with a rectal tear?

A

PRolapse tear through the anus

-due to laxity of perirectal tissues

38
Q

When should you use a Prolapse tear through the anus repair for a rectal tear in horses?

A

1) Post partuirent mares

2) Grade 4 tears
- pneumoperitoneum

39
Q

What stapler can be used to prolapse a rectal tear through the anus?

A

TA 90 or SI

-overseen

40
Q

What surgical approach would you use for a rectal tear that is not accessible through the anus?

A

1) Laparoscopy
- hand assisted per rectum

2) Ventral midline celiotomy
- more commonly done if grade 4 with eviservation (to assess blood supply)

41
Q

You have a grade 4 rectal tear with evisceration what surgical approach is best?

Why?

A

VENTRAL midline celiotomy

*We need to assess the viability of the intestine

42
Q

T/F: most rectal tears occur 15-20cm cranial to the anus

A

TRUE

43
Q

How many bypass rectal tear procedures are there and what are they?

A

1) Temporary indwelling rectal liner (TIRIL)

2) Colostomy

44
Q

How do bypass rectal tear procedures work?

A

Divert feces away from tear

  • with/without direct repair of tear
  • prevent progression of 3 to 4 grade
  • protect suture line
  • prevents impaction of feces in tear
  • decreases fecal contamination
45
Q

For the TIRIL (temporary indwelling rectal liner) repair, what surgical approach should be taken?
-describe the positioning of the TIRIL

A

CAUDAL midline celiotomy + assistant per rectum

TIRIL is positioned:
10cm cranial from tear
10cm protruding from rectum

46
Q

T/F: Loop colostomy is preferred over End colostomy?

A

TRUE

-easier to perform and to revert

47
Q

T/F: Colostomy should be performed in lateral recumbancy

A

FALSE
It should be done standing
-shifting of muscle layers —>inaccurate placement
-risk of traumatizing stoma upon recovery

48
Q

What are the advantages of colostomy over TIRIL?

A
  • Better control of feces diversion for longer time
  • better for large tears or those too far cranial

*TIRIL only lasts 9-12 days

49
Q

Why are 2 incisions required for the loop colostomy?

A

High flank incision
-to find and prepare colon loop

Low flank incision (~10cm)
-Stoma placement

50
Q

What are the land marks for stoma placement (low flank incision) of a loop colostomy?

A

1) midway betweeen flank fold and last rib
2) @ level of flank fold
3) parallel to last rib

51
Q

T/F: Ventral edema develops and resolves spontaneously with loop colostomy

A

TRUE

52
Q

How long do you have to wait to reverse colostomy?

A

6 weeks or more usually

53
Q

What does the colostomy reversal involve?

A

1) lateral recumbency

2) “en bloc” resection of stoma
- flank laparotomy

3) small colon anastomoses
- SC + Lemberg

54
Q

T/F: Initial management of rectal tears affects survival and liability

A

TRUE