Hernias

Question 1

congenital hernia locations

Answer 1

• umbilical
• inguinal
• scrotal
• femoral
• peritoneal-pericardial diaphragmatic
• hiatal

Question 2

traumatic/acquired hernia locations

Answer 2

• abdominal
• incisional
• diaphragmatic

Question 3

3 parts of the hernia

Answer 3

1. The ring: defect in the wall
2. The sac: peritoneum lining the hernia contents
3. Contents: organ/tissue that has moved into the hernia ring

Question 4

What is a true vs false hernia?

Answer 4

True hernia = w/ peritoneal lining

False hernia = no peritoneal lining

Question 5

why are incarcerated and strangulated hernias considered non-reducible?

Answer 5

Incarcerated = adhesions have formed which prevents reduction
Strangulated = blood supply to a herniated organ is compromised

Question 6

what makes up the internal inguinal ring?

Answer 6

internal abdominal oblique + inguinal ligament + rectus abdominis

Question 7

what makes up the external inguinal ring?

Answer 7

longitudinal slit in aponeurosis + external abdominal oblique muscle

Question 8

structures in the inguinal canal

Answer 8

• genital branch of genitofermoral a., v., n.
• external pudendal vessels
• spermatic cord (m)/ round lig(f)

Question 9

what other congenital abnormalities are associated with umbilical hernias?

Answer 9

• cryptorchid
• peritoneal-pericardial diaphragmatic
• ventricular septal defect

Question 10

umbilical hernia sx

Answer 10

1. incision avoiding hernia contents
2. Amputate hernia sac
3. Reduce contents
   * do at same time as spay/castrate
4. Close ex. rectus sheath

Question 11

what dog breed is predisposed to scrotal hernias?

Answer 11

chondrodystrophic dogs esp. Shar peis

Question 12

emergency sx of traumatic hernias is indicated when…

Answer 12

• animal cannot be adequately stabilised due to hernias
• herniated organs progressively turgid or incarcerated
• penetrating wounds explored after emergency resus

Question 13

what is the most important strength layer when closing the ventral abdominal wall?

Answer 13

external rectus fascia

Question 14

77-85% of traumatic diaphragmatic hernias are due to?

Answer 14

blunt force - automobile accidents, kicks, falls

Question 15

PE findings assoc. w/ a diaphragmatic hernia

Answer 15

• resp. signs and exercise intolerance
• muffled or asymmetric thoracic auscultation
• hyporesonance (pleural effusion)
• hyperresonance (gastric tympany)

Question 16

how can traumatic diaphragmatic hernias lead to cardiac dysrhythmias?

Answer 16

ventilation perfusion mismatch

Question 17

all patients experiencing significant trauma should get what radiograph?

Answer 17

a lateral thoracic and abdominal rad.

Question 18

radiographic findings w/ thoracic hernia

Answer 18

• partial loss of the normal line of the diaphragm
• obscured or displaced cardiac shadow
• abdominal viscera w/in the thoracic cavity
• cranial displacement of pylorus or duodenum: traction on gastro-hepatic ligament

Question 19

which diaphragmatic muscles are usually ruptured in a thoracic hernia?

Answer 19

costal muscles (85% unilateral)

Question 20

what precautions do you have in mind when ventilating a dog w/ chronic diaphragmatic herniation?

Answer 20

• do not force reinflation – barotrauma, re-expansion pulmonary oedema + reperfusion injury risks
• thus low pressure ventilation

Question 21

approach to repair a thoracic hernia?

Answer 21

ventral midline coeliotomy w extension to median sternotomy

Question 22

closure technique of thoracic hernias

Answer 22

• debride sparingly
• interrupted sutures aid in reconstruction
• simple cont. pattern best = min. suture materials and fewer stiff cut ends
• start dorsally and progress ventrally
• correct pneumothorax w/ thoracostomy tube

Question 23

indications for AB in post-op tx of a traumatic diaphragmatic hernia

Answer 23

• liver herniation

- perforation of the GIT

Question 24

what is a congenital PPDH?

Answer 24

congenital peritoneo- pericardial-diaphragmatic hernia

= communication btwn abdomen and pericardial sac

Question 25

concurrent defects assoc. w/ PPDH

Answer 25

- sternal defects - cranial midline abdominal wall hernia - umbilical hernia - intracardiac defects (VSD)

Question 26

breeds predisposed to PPDH

Answer 26

Weimaraners and cocker spaniels

Question 27

thoracic rad findings of congenital PPDH

Answer 27

- enlarged cardiac silhouette - dorsal elevation of trachea - overlap of heart and diaphragmatic borders - discontinuity of diaphragm - gas-filled structures in pericardial sac +/- sternal defects

Question 28

prognosis of PPDH w/ surgical correction

Answer 28

excellent UNLESS re-expansion/reperfusion pulmonary oedema (poor)

Question 29

define type 1 hiatal hernia

Answer 29

sliding protrusion through oesophageal hiatus of gastroesophageal junction +/- gastric fundus

Question 30

breeds predisposed to hiatal hernias

Answer 30

shar peis, bulldogs, brachys

Question 31

CS of hiatal hernias

Answer 31

- regurgitation - oesophagitis, megaO - v+, haematemesis, anorexia, weight loss (poor BCS)

Question 32

cause of hiatal hernia

Answer 32

an anatomical oesophageal hiatal malformation - loose connection w/ diaphragm

Question 33

sx treatment of hiatal hernias

Answer 33

dorsal hiatal herniorrhaphy

Question 34

post op support of hiatal hernias

Answer 34

1. Metoclopramide: sensitizes upper GIT to acetylcholine --> inc. prssure of gastro-oesophageal junction + a prokinetic 2. Erythromycin: increases lower oesophageal sphincter pressure and stim. migrating motility complexes + peristalsis 3. PPIs 4. Anti-emetic: maropitant/ondansetron 5. No food for 12h post op

Question 35

erythromycin dose as GIT support

Answer 35

1mg/kg q8h slow IV over 30min

Question 36

metoclopramide dose

Answer 36

1mg/kg IV | 2mg/kg/hr CRI