The Commonest Hernias Flashcards
1
Q
What is a hiatal hernia?
A
protrusion of abdominal contents, most commonly the abdominal oesophagus, cardia and part of the stomach through the oesophageal hiatus into the caudal mediastinum
2
Q
How many types of hiatal hernia are there?
A
4
3
Q
Define type I hiatal hernia
A
Known as a sliding hiatal hernia, the gastro-oesophageal junction herniates.
4
Q
Define type II hiatal hernia
A
Part of the stomach herniates but the gastro-oesophageal junction remains.
5
Q
Define type III hiatal hernia
A
The gastro-oesophageal junction and part of the stomach herniates.
6
Q
Define type IV hiatal hernia
A
Other abdominal organs in addition to the stomach herniate.
7
Q
Which type of hiatal hernia is most common?
A
Type I
8
Q
Are hiatal hernias typically congenital or acquired?
A
Congenital
9
Q
Congenital hiatal hernias have been well recognised in what breed?
A
Shar Pei
10
Q
Young dog breeds that have been recognised as having hiatal hernia? (2)
A
English bulldog
French dog
11
Q
How obstruction of the upper airway could contribute to development of a hiatal hernia?
A
An upper airway obstruction a greater negative pressure must be generated to move air from the atmosphere into the thorax.
The resulting pressure differential between the abdomen and thorax is greater during inspiration in these circumstances and this pressure differential may be great enough for the abdominal oesophagus and cardia to be pushed (or sucked) into the thorax.
12
Q
How common is a hiatal hernia 2ry to laryngeal paralysis (same pathophysiology as BOAS)?
A
Rare
13
Q
How common is hiatal hernia 2ry to trauma of diaphragm muscles/nerves?
A
Rare
14
Q
How common is hiatal hernia 2ry to tetanus?
A
Rare
15
Q
What are some of the potential consequences of malpositioning of the gastro-oesophageal junction? (3)
A
- Reduced pressure of the gastro-oesophageal sphincter with resulting gastro-oesophageal reflux
- Oesophagitis and oesophageal dysmotility
- Slow passage of food from the caudal oesophagus to the stomach similarly resulting in oesophagitis and oesophageal dysmotility.
16
Q
Clinical signs of hiatal hernia? (6)
note: can be assymptomatic
A
- Regurgitation of saliva (“white foam or froth”) or undigested food (differentiate from vomiting by presence/absence of abdominal effort)
- Hypersalivation, usually associated with feeding
- Gulping, swallowing
- Vomiting
- Poor body condition/weight loss
- Respiratory signs (tachypnea, dyspnea, cough, etc if secondary aspiration pneumonitis or pneumonia)
17
Q
Which food may hiatal hernia be worse with?
A
Chunky/dry food
18
Q
If congenital or 2ry to BOAS when do clinical signs of hiatal hernias develop?
A
First few months/years
19
Q
Why is diagnosing a sliding hiatal hernia difficult?
A
As the diagnosis will not be evident when the hernia is reduced
20
Q
How to aid hiatal hernia diagnosis?
A
By increasing abdominal pressure (by applying pressure to the abdomen or elevating the hindlimbs) to encourage herniation.
21
Q
What is the preferred diagnosis of hiatal hernia? why?
A
A fluoroscopic barium swallow study is the preferred method of diagnosis as it allows real time assessment of oesophageal motility and gastric regurgitation
22
Q
Cons of fluoroscopy? (2)
A
- Exposure to vet
- Conscious patient
23
Q
What may be seen on thoracic imaging to diagnose a hiatal hernia?
A
A soft tissue/gas opacity within the mediastinum in the caudodorsal thorax (where the oesophagus is located)
24
Q
Oesopagoscopy:
What is seen with a hiatal hernia is a gastroesophgeal herniation is present at the time?
A
A pink “mass” within the distal oesophagus.
25
Other than a mass, what might be seen in distal oesophagus with hiatal hernia and oesophagoscopy?
Oesophagitits
26
In these dogs where the clinical signs are consistent with hiatal hernia, if other differential diagnoses have been excluded and there has been no response to symptomatic treatment, how can diagnosis be confirmed?
Exploratory celiotomy
27
How MECHANISMS treat 2ry reflux oesophagtitis (3)
Reducing gastric acid secretion:
Protection of the oesophageal mucosa -
Improving lower oesophageal sphincter tone:
28
Reducing gastric acid secretion: Pharacology (2) and examples (3,1)
Antacids - Histamine H2 receptor blockers: famotidine, ranitidine, cimetidine;
Inhibition of H+/K+-ATPase - omeprazole
29
Protection of the oesophageal mucosa - drug that can be used?
Sucralfate
30
Improving lower oesophageal sphincter tone- Pharmacology (1) and drugs that can be used (2)
Prokinetics to enhance gastric emptying rate and increase lower oesophageal sphincter tone - cisapride, metoclopramide.
31
How can diet help treat hiatal hernia?
Low fat diet, slurry/soft consistency, small frequent meals, postural feeding.
32
Medical treatment of hiatal hernias
- 2ry reflux oesophagititis
- Diet modification
- Improve upper airway obstruct
- trx 2ry pneumonia
33
How long should a patient be stabilized medically before proceeding to surgery for a hiatal hernia?
2-4 weeks
34
Hiatal hernia sx is approached via a midline cranial ceoliotomy, what is performed (4)
- Diaphragmatic hiatal reduction and phrenoplasty
- Oesophagopexy
- Left sided gastropexy
35
Hiatal hernia reapir:
what ligament is cut to allow retraction of the left lateral lobe of the liver to allow observation of the oesophageal hiatus?
Left triangular ligament of the liver
36
How to identify oesophagus during hiatal hernia repair?
Pass orogastric tube
37
During hiatal hernia repair; how to free the oesophaus from diaphragm ventrally?
CARE - why?
- Carefully cut the phrenico-oesophageal ligament ventrally to free the oesophagus from the diaphragm ventrally
- CARE: to preserve the vagal trunks and oesophageal vessels.
38
During hiatal hernia repair before cutting the phrenico- oesophaeal ligament; warn the anaesthetists, why?
A pneumothorax is created at this point in the surgery, the anaesthetist has been advised of and prepared for this.
39
Following surgical approach; how the hernia then repaired
- Retract the cardia caudally.
- Reduce the size of the hiatus by pre-placing 3-5 sutures of 3 metric polydioxanone or polypropylene in a cruciate mattress or single interrupted pattern across the left and right diaphragmatic crura at the oesophageal hiatus.
- Tie these sutures with the large bore orogastric tube in place, starting at the ventral aspect of the hiatus and progressing dorsally.
40
After reducing a hiatal hernia; how large should the hiatus be?
To allow passage of stomach tube
41
How to perform an oesophagopexy?
By circumferentially placing single interrupted sutures using 2 or 3 metric suture material as described above between the free edge of the hiatus and the lateral and ventral aspects of the oesophagus.
42
What traction should be on the stomach following gastropexy after hiatal hernia repair?
Mild caudal traction on the stomach.
43
Following hernia repair before abdo closed; what must happen?
Drain the chest through the diaphragm using a needle/catheter, extension tubing, 3 way tap and syringe or place a thoracostomy tube.
44
During a hiatal hernia repair; how to improve cranial access?
Extension of coeliotomy incision cranially as caudal sternotomy
45
How can a hiatal hernia be repaired without a pneumothorax developing?
Reducing the size of the oesophageal hiatus by suturing across the diaphragmatic crura ventrally (or ventrally and dorsally) without cutting the phrenico-oesophageal ligament.
46
Pros of:
Reducing the size of the oesophageal hiatus by suturing across the diaphragmatic crura ventrally (or ventrally and dorsally) without cutting the phrenico-oesophageal ligament. (20
- No pneumothorax
- Reduced risk to oesophageal vessels
47
Reducing the size of the oesophageal hiatus by suturing across the diaphragmatic crura ventrally (or ventrally and dorsally) without cutting the phrenico-oesophageal ligament.
Cons (2)
- No visualisation correction is in right place
- No confirmation of suture placement across crura and between crura and oesophagus
48
Some surgeons use what surgical technique during oesophagopexy.
Make a 2-3 cm partial thickness (serosal) oesophageal incision and a corresponding incision in the superficial seromuscular layer of the left diaphragm
49
How long should post op regrugitatio/oesophagitis meds be given and why?
Give for 2 weeks
GA/surgery/drugs can excerbate
50
What post operative instructions regarding exercise should be given after hiatal hernia repair?
Strict rest and avoidance of any activity that increases intra-abdominal pressure (e.g. coughing, barking) or increases the pressure differential between the thorax and abdomen (no jumping/stairs)
51
After several days of hiatal hernia repair postoperatively if regurgitation continues as preoperatively or has increased in severity, what should happen?
Dogs should be evaluated by a fluoroscopic barium swallow study (if available) to check that the oesophageal hiatus has not been reduced excessively
52
Hiatal hernia with surgical repair, has what prognosis?
Good
53
What can cause long term regurgitation following hiatal hernia repair? How is this managed?
- Oesophageal dysmotility; conservative manage
54
Which structures make up the pelvic diaphragm? (3)
Levator ani muscles
Coccygeus muscles and their internal fascial coverings
Coccygeus muscles and their external fascial coverings
55
In most perineal hernias the defect is between ..?
The levator ani, internal obturator and external anal sphincter muscles
56
What is the following perineal hernia termed:
Between levator ani, internal obturator and external anal sphincter muscles
Caudal perineal hernia
57
What is affected with a dorsal perineal hernia?
Between the levator ani and coccygeus muscles
58
What is affected with a sciatic perineal hernia?
Between the coccygeus and sacrotuberous ligament
59
What is affected with a ventral perineal hernia?
Between the ischiourethralis, bulbocavernosus and ischiocavernosus muscles
60
Pathogenesis of perineal hernia?
unknown - atrophy of muscle du to something
61
Age/sex pre disposition to perineal hernia?
Middle - older
Entire male
62
Can perineal hernias happen in castrated males?
Yes - tends to be those castrated later
63
Discuss prostate and perineal hernia.
- Previously thought prostate caused hernia
- Now thought to co exist as both in older entire males
64
What about prostate disease can effect perineal hernia prognosis?
Enlarged prostate - tenesums - effect surgical repair wound
65
Atrophy of the levator ani and coccygeus muscles results in loss of support to the rectal wall and loss of division between the abdominal and pelvic cavities.
What is the consequence of this?
- Loss of support to lateral rectal wall (s)
- Loss of division between abdominal and pelvic cavities
66
Select all the possible structures that could herniate through a failed pelvic diaphragm. (5)
- Omentum
- Jejenum (mobile long mesentery)
- Bladder
- Prostate
- Paraprostatic cyst
67
What does Loss of support to the lateral rectal wall(s) result in?
Accumulation of faeces within the rectum and defecatory tenesmus.
68
What is this termed:
rectum to deviate into a unilateral hernia, expand asymmetrically into a unilateral hernia
rectal sacculation
69
What is this termed:
dilate circumferentially into a bilateral perineal hernia
Rectal dilation
70
What are the potential consequences of the bladder retroflexing into a perineal hernia? (3)
- Dysuria
- Partial/complete obstruction
- Kinking of urethra
71
Clinical signs of perineal hernia?(5)
- Perineal swelling ventrolateral to the anus
- Defecatory tenesmus
- Constipation
- Dyschezia
- Dysuria/anuria if bladder
72
Perineal swelling: T or F
Not all dogs with a perineal hernia have a perineal swelling,
True
73
How to confirm a perineal hernia?
A rectal examination which confirms a loss of lateral support to the rectum.
74
What may prevent rectal wall defect being palpable with a perineal hernia?
An intrapelvic paraprostatic cyst that may “fill” the perineal hernia
75
What needs to be performed pre surgery of a perineal hernia?
- Haem + biochem
76
If the bladder is retroflexed into the perineal hernia; what is next step?
pass a soft well lubricated urinary catheter to empty the bladder;
77
If the bladder is retroflexed into the perineal hernia; what may be on bloods?
- Hyperkalaemia
- Azotemia
78
After passage of a urinary catheter and emptying of the bladder, with one ventroflexed into perineal hernia; how to encourage replacement into position?
Palpation of the perineal swelling with the hindlimbs elevated will often result in the bladder returning to a normal abdominal position (although recurrent bladder herniation is likely).
79
If the bladder has retroflexed and a urethral catheter will not pass with a perineal hernia - what to do?
Drain the bladder by needle centesis through the perineum (preferably under ultrasound guidance). A urethral catheter can sometimes then be passed once the bladder is empty.
80
How to assess prostate with a perineal hernia?
U/S
81
To rule out other causes of defecatory tenesmus; what imaging is recommended?
caudolateral abdominal and pelvic radiograph (include the perineal region)
82
If the dog is azotemic and hyperkalemic, associated with retroflexion of the bladder, this does not need to be addressed before general anaesthesia and hernia repair.
FALSE
83
Intravenous fluids should be started to establish diuresis and an indwelling urinary catheter can be placed to allow urine flow, drained every A)? or connected to B)
A) 3-4 hours
B) closed collecting system
84
Surgical technique for perineal hernia repair?
Internal Obturator Transposition Technique
85
Older textbooks may recommend inclusion of the sacrotuberous ligament as routine in a perineal hernia repair.
This is not recommended anymore because: (2)
- The sciatic nerve runs over the lateral aspect of the sacrotuberous ligament but is not easily seen intraoperatively so it may be included in the suture;
- The sacrotuberous ligament is located quite laterally and therefore may cause more tension on the hernia repair (increasing the risk of dehiscence) and gives a less anatomical closure with more distorsion (increasing postoperative patient discomfort and giving a poorer functional result).
86
How might you reconigse inadvertent suture placement around sciatic nerve intra op?
If no epidural; a HL jump
87
How might you recognise inadvertent suture placement around sciatic nerve post top?
Extreme pain on recovery from GA
88
What would you do if the dog woke up from anaesthesia in extreme pain and had a non-weight bearing lameness on the side of perineal hernia repair after you had included sutures around the sacrotuberous ligament?
Re-anaesthetise the dog immediately, make a dorsal approach to the hip (where the suture around the sciatic nerve should be obvious) and remove the suture.
89
Antibiotics post perineal hernia repair?
Continuation of antibiotics beyond completion of surgery that has progressed routinely is unwarranted because this is a clean surgical procedure.
90
Post perineal hernia op considerations?
- Analgesia
- Monitor wound (esp for faecal soiling)
- Monitor defecation - can use laxative/softner
- Monitor urination
- Exercise restriction
91
The outcome for perineal hernia treated surgically with internal obturator transposition is generally good, with reported success rates of..?
95-100%
92
When do patients with bladder retroflexion and perineal hernias have poorer outcomes?
If the bladder has been overstretched and has become atonic.
93
Specifics of castration at time of perineal hernia repair? (2)
- Closed
- Harvest tunica vaginalis and wrap in a sterile saline soaked swab for use as an autologous graft that can be used to reinforce the hernia repair if required.
94
Prevent faecal contamination during perineal hernia repair?
Purse string suture
95
Positional a patient for Internal Obturator Transposition Technique
Position the patient in ventral recumbency with the tail fixed forward over the back. The legs should hang over the edge of the operating table and the pelvis should be elevated with soft padding.
96
Incision for Internal Obturator Transposition Technique
lateral to the tail base, extending down towards the tuber ischii, then bluntly dissect the fat in the ischiorectal fossa to reveal the hernial sac.
97
Place Gelpi retractors to aid exposure of the surgical site, then identify these anatomical structures (Internal Obturator Transposition Technique): (6)
The caudal rectal vessels and nerve, just dorsal to the caudal border of the internal obturator muscle
The sacrotuberous ligament, inserted on the lateral end of the tuber ischii
The external anal sphincter muscle
The levator ani muscle, lying deep to the caudal rectal vessels and nerve
The coccygeus muscle, lying lateral to the levator ani muscle
The pudendal nerve, internal pudendal artery and vein lying over the coccygeus and internal obturator muscles.
98
How to - Elevation of the internal obturator muscle from the ischium
(1 - incision. 2 - avoid, 3- divide)
Incise the caudal border of the internal obturator muscle along the dorso-caudal border of the tuber ischii using a scalpel, then elevate the muscle from the ischium.
Avoid the ischio-urethral muscle medially and only elevate the muscle as far cranially as the caudal limit of the obturator foramen.
Divide the tendon of insertion of the internal obturator muscle where it crosses the lateral border of the ischium, avoiding the pudendal and sciatic nerves. This allows the internal obturator to be rotated dorsally and medially to reinforce the pelvic diaphragm muscles without tension.
99
Using the Internal Obturator Transposition Technique:
Which direction are sutures tighted?
Dorsal - ventral
99
Using the Internal Obturator Transposition Technique:
If muscles are severely atrophied; what can reinforce the repair?
tunica vaginalis can be sutured over the muscles used in the hernia repair as reinforcement to the repair.
99
What suture material for Internal Obturator Transposition Technique?
monofilament absorbable (for example polydioxanone) or monofilament nonabsorbable sutures
100
Internal Obturator Transposition Technique:
Where are the pre placement of sutures locations? (3)
- 2-3 interrupted Between the levator ani/coccygeus and the external anal sphincter, avoiding the anal sacs and the rectal wall
- 2-3 simple interrupted sutures between the levator ani and coccygeus muscles and the internal obturator muscle
- pre-place 2-3 sutures between the internal obturator and the external anal sphincter
101
If the levator ani/coccygeus is severely weakened or atrophied and will not hold sutures securely; what can be included duringInternal Obturator Transposition Technique
sacrotuberous ligament may be included in these dorsolateral sutures.
102
What is the anal sphincter covered in and how is it identified?
fat identify with palp
103
How to close after internal obturator transposition technique?
Appose the fat in the ischiorectal fossa using a few absorbable simple interrupted sutures to reduce the dead space. Some dead space will exist between the elevated internal obturator and the ischium but drain placement is not usually recommended.
Appose the subcutis using an absorbable continuous suture.
Appose the skin using either non-absorbable interrupted skin sutures or a buried absorbable continuous intradermal suture.
104
After a internal obturator transposition technique, a rectal exam is done; what is looked for?(2)
- Ensure walls supported
- No suture in rectal wall
