Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Eq ACVS Phase 1 > Ch.39 Rectum and Anus > Flashcards

Ch.39 Rectum and Anus Flashcards

1
Q

How long is the rectum in the adult horse?

A

30cm (12inches)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How long is the anal canal in adult horses?

A

5cm (2inches)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The internal anal sphincter is what sort of muscle?

A

Smooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The external anal sphincter is what sort of muscle?

A

Striated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The levator ani muscle arises from where?

A

Ischiatic spine and sacrotuberal ligament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What overcomes the tendency of the anus to prolapse during defecation?

A

Levator ani muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the minimal measures required to prevent anal tears

A

Copious lubrication, sedation, adequate restraint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Most rectal tears caused by rectal palpation occur due to what?

A

Rupture of the rectal wall as it contracts around the examiner’s hand not finger tips

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What horses are most prone to rectal tears?

A

Arabian, American miniature, mares, horses >9yo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In what direction are IDIOPATHIC rectal tears orientated?

A

Transversely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Grade 1 rectal tear

A

Only mucosa and submucosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Grade 2 rectal tear

A

Muscular layer only - Rare (2/89)

Causes mucosa and submucosa to prolapse through the muscle defect - creates site for fecal impaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Grade 3a rectal tear

A

All layers except serosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Grade 3b rectal tear

A

All layers except mesorectum and retroperitoneal tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Grade 4 rectal tear

A

All layers (mucosa, submucosa, muscular, serosal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Most rectal tears occur where

A

Dorsally, 4-60cm from the anus and orientated parallel to the longitudinal axis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The only cause which influences size of rectal tear is what?

A

Dystocia (25cm median)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How long following a rectal tear will a horse show sings of shock and peritonitis

A

2 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Initial first aid in tx of rectal tear

A

1 - Reduce activity of rectum - sedation/buscopan/epidural

2 - Gentle removal of feces

3 - Tx septic shock/peritonitis - flunixin, gent, k-pen, metro, IV fluids

4 - Epidural and pack rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is used to pack a rectum with a grade 3 rectal tear?

A

3inch stockinette filled with 0.25kg of moistened rolled cotton sprayed with povidone - iodine and lubricated with surgical gel. Should fill the rectum without distention to a point 10cm cranial to the tear.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How can a TIRL (Temporary Indwelling Rectal Liner) be fashioned?

A

Palpation sleeve minus hand glued to a 5cm diameter 7.5cm long rectal prolapse ring with holes through with Dacron loops are laced

22
Q

After how long will the TIRL (Temporary Indwelling Rectal Liner) be passed in faces

A

9-12 days

23
Q

Maintenance of a horse with a TIRL (Temporary Indwelling Rectal Liner)

A

Cross tie, oil, laxatives, soft feed

24
Q

Where can a loop colostomy be positioned on the abdomen?

A
  1. High left flank
  2. Low left flank
  3. Ventral midline
25
Q

Reasons for a celiotomy to be performed to treat a rectal tear?

A
  1. If colic preceded the tear
  2. If intra-abdominal repair of the tear in considered feasible
  3. To empty the large and small colons to reduce stress on the tear
26
Q

Why should a colostomy not be performed under GA

A
  1. Muscle layers shift making accurate placement challenging
  2. Expensive
  3. Dehisence in rough recovery
27
Q

Where is the low flank colostomy placed

A

Left flank, at level of stifle fold - midway btw fold and costal arch

28
Q

What size and angle should the low flank incision be for a colostomy

A

8-10cm
20-30 degrees dorsad from cranial to caudal

29
Q

When performing a loop colostomy, the segment for the stoma must be how far from the rectum?

A

1 meter

30
Q

When performing a loop colostomy which end must most ventral

A

Orad

31
Q

What size incision should be made in the anti-mesenteric tenia of the colon to perform the stoma?

A

8cm - allowing the opening formed to be the same diameter as the small colon lumen

32
Q

In an end colostomy the aboard section os closed using what method

A

Parker-Kerr

33
Q

Complication of end colostomy

A

Aborad end may atrophy reducing its length and diameter by 50%

34
Q

How to avoid aborad atrophy in loop colostomy?

A

High volume water lavage starting 5-7 days post tear

35
Q

How long typically before a loop colostomy is reversed

A

6 weeks

36
Q

What is the main concern of a staples side to side anastomosis of the small colon post colostomy

A

It transects all the circular muscle fibres along the length of the stoma by necessity - with no circular mm contraction intestinal contents cannot be expelled into the narrow lumen - increase risk of impaction

37
Q

Preferred suture for transrectal closure of rectal tear

A

5 Dacron w 6-8cm half circle cutting needle in the middle of the suture

38
Q

How long are rectal sutures typically left in place after a transrectal recta tear repair

A

12-14 days

39
Q

Prognosis for Grade 1 rectal tears w conservative management

A

93%

40
Q

Prognosis for Grade 3a/3b rectal tears w conservative management

A

70%/69%

41
Q

Type 1 rectal prolapse

A

Only the rectal mucosa and submucosa project through the anus

42
Q

Type 2 rectal prolapse

A

Complete prolapse of the full thickness of all or part of the rectal ampulla

43
Q

Type 3 rectal prolapse

A

Small colon intussuscept into the rectum in addition to Type 2 (complete full thickness of all or part of the rectal ampulla)

44
Q

Type 4 rectal prolapse

A

The peritoneal rectum and variable lengths of small colon form an intussusception through the anus.

45
Q

Most common type of rectal prolapse?

A

1 and 2

46
Q

Treating types 1 and 2 rectal prolapses

A

Decrease edema/irritation - glycerine, sugar, lidocaine jelly, lidocaine enema
Epidural
Umbilical tape - purse string - open every 2-4 hours (2 days)
Hold off feed 24hrs
Then laxative diet - 10 days

47
Q

When might a submucosal resection be indicated regarding rectal prolapse.

A

If prolapsed tissue is devitalised
Recurring prolapse after conservative tx
Horse continues to strain

48
Q

Why is the mucosa apposed in a submucosal resection when tx a rectal prolapse

A

Cover all denuded areas
Prevent extensive granulation tissue
Prevent scarring and stricture formation

49
Q

Prognosis for atresia ani

A

Good with sx intervention

50
Q

Prognosis for atresia coli

A

Poor

51
Q

What % of grey horses have melanoma

A

80% of grey horses over 15 years

Eq ACVS Phase 1 (72 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions