Auer Ch 31 Esophagus

Front 1

Esophagus anatomical position:

Back 1

dorsal to trachea in cranial 1/3 of neck, lateral (left) of trachea in middle 1/3 of the neck, ventral to trachea at thoracic inlet, cervical portion is 50% of the length

Front 2

Region of the esophagus most amenable to surgery:

Back 2

cervical

Front 3

Esophageal layers:

Back 3

from outer to inner, tunica adventitia, tunica muscularis, tela submucosa, tunica mucosa

Front 4

Types of esophageal muscle:

Back 4

cervical portion striated, blend to smooth muscle in the caudal thoracic portion

Front 5

Layer with the highest tensile strength of the esophagus layers for closure of an esophageal incision:

Back 5

mucosa

Front 6

Lining of mucosa:

Back 6

stratisfied squamous epithelium

Front 7

Arterial supply to the cervical esophagus:

Back 7

carotid arteries

Front 8

Arterial supply to the thoracic esophagus:

Back 8

bronchoesophageal and gastric arteries

Front 9

Esophageal vascular pattern:

Back 9

arcuate and segmental, without much collateral circulation

Front 10

Innervation to the esophagus:

Back 10

9th and 10th cranial nerves, sympathetic trunk, mesenteric ganglia.

Front 11

Odynophagia:

Back 11

painful swallowing

Front 12

Propagation speed of a food bolu:

Back 12

proximal 2/3 of the esophagus, 9.4 cm/s, caudal 1/3, 4.6 cm/s

Front 13

Positive contrast esophagram:

Back 13

horse is fed or given 120 mL barium paste by mouth, outlines longitudinal mucosal folds in the undistended lumen, localizes obstruction or disruptions of the lumen

Front 14

What is identified with large volume barium contrast esophgraphy?

Back 14

highlight strictures, prestenotic dilation, and space occupying masses

Front 15

Double contrast esophagraphy:

Back 15

administration of liquid barium, followed by an equal volume of air

Front 16

What is identified with double contrast esophagram?

Back 16

evaluation of mucosal folds and detection of mucosal lesions

Front 17

Negative contrast esophagraphy:

Back 17

without contrast material and only insufflation of the esophagus via endoscopy or introduction of air through a NGT

Front 18

What is identified with negative contrast esophagraphy?

Back 18

cranial esophagus strictures

Front 19

Functionally distinct manometric regions:

Back 19

cranial esophageal sphincter, caudal esophageal sphincter, fast region, and slow region

Front 20

Location of fast esophageal region:

Back 20

cranial 2/3rds

Front 21

Location of slow esophageal region:

Back 21

caudal 1/3

Front 22

Approaches to the esophagus:

Back 22

ventral, ventrolateral, thoracotomy

Front 23

Used of ventral approach:

Back 23

esophagotomy, esophagomyotomy, and resections of the cranial 1/3 of the esophagus

Front 24

Use of ventrolateral approach:

Back 24

esophagostomy (feeding tube placement) or for approach to the distal ¼ of the cervical esophagus

Front 25

Use of thoracotomy:

Back 25

access the distal half of the esophagus

Front 26

Clinical objective of esophageal surgery:

Back 26

obtain leak proof healing of a primary anastomosis or incision, dilate a restricted lumen, and return an enlarged or disrupted esophagus to near normal size and function

Front 27

Describe ventral approach:

Back 27

dorsal recumbency, 10 cm incision made ventral midline, sternothyroid, sternohyoid, omohyoid muscles bluntly separated, expose trachea, retract trachea to right, esophagus exposed by conservative dissection loose adventitial tissue

Front 28

Describe ventrolateral approach:

Back 28

dorsal, RLR, or standing, 5 cm incision made just ventral to jugular vein, sternocephalicus and brachiocephalicus separated, blunt dissection of deep cervical fascia exposes the esophagus

Front 29

Why is ventrolateral approach advantageous for esophagostomy?

Back 29

better access to the middle and distal cervical access due to increased ventral cervical musculature

Front 30

Use of thoracotomy approach to the esophagus:

Back 30

vascular ring anomalies, or esophageal lesions in the distal half of the esophagus that do not require penetration of the esophageal lumen

Front 31

Medical adjuncts to esophageal impaction:

Back 31

atropine (0.02 mg/kg), acepromazine, oxytocin (0.11-0.2 IU/kg), xylazine

Front 32

Affects of atropine of esophagus:

Back 32

esophageal relaxation, reduction of salivary secretions

Front 33

Closure after esophagotomy:

Back 33

apposition of the mucosa-submucosa with continuous suture (with knots to the lumen), esophageal musculature in interrupted pattern, place drain, closure of the approach incision in 2-3 layers

Front 34

Benefits of drain placement:

Back 34

remove dead space fluid, monitor for saliva leakage

Front 35

Post-operative esophagotomy care:

Back 35

withholding feed for 48 hours, supportive fluid therapy, electrolyte correction

Front 36

Esophageal rupture management:

Back 36

early establishment of ventral drainage

Front 37

Complications of esophageal rupture:

Back 37

Feed and saliva accumulation causes severe soft tissue inflammation, infection, mediastinitis, or plueritis

Front 38

How long should Esophagostomy tubes remain in place?

Back 38

at least 7 to 10 days to allow granulation tissue to form a stoma around the tube

Front 39

Types of esophageal stricture:

Back 39

mural lesions involving only the adventitia and muscularis, rings that involve only the submucosa and mucosa, and annular stenosis that affect all 4 layers

Front 40

When do strictures form and resolved?

Back 40

maximally formed by 30 days after esophageal trauma, in most cases return to normal after 60 days

Front 41

Disadvantages of bougienage or dilators for esophageal stricture:

Back 41

require special equipment and may fail due to the chronicity of the stricture

Front 42

Optimal surgical intervention for esophageal stricture:

Back 42

delayed for at least 60 days after the original trauma

Front 43

Surgical options for esophageal stricture:

Back 43

esophagomyotomy, partial or complete resection and anastomosis, or patch grafting

Front 44

Complications after resection and patch grafting:

Back 44

leakage of luminal contents, reformation of the stricture.

Front 45

Best approach for mural strictures:

Back 45

esophagomyotomy

Front 46

Describe esophagomytomy:

Back 46

ventral approach, linear incision made into muscularis, not penetrating mucosa, NGT passed through the lumen, muscularis separated from the mucosa by sharp dissection circumferentially myotomy not closed

Front 47

Describe partial resection:

Back 47

approached as longitudinal esophagomyotomy, mucosal stricture resected within the muscular tube, mucosal edges apposed without tension, if performed for esophageal ring, myotomy closed, if performed for annular stenosis, myotomy is not closed

Front 48

When is a complete resection and anastomosis is performed?

Back 48

esophagus has ruptured and the muscularis is not viable

Front 49

Describe complete resection and anastomosis:

Back 49

esophagus exposed throug ventral approach, lumen occluded using rubber drains or umbilical tape secured circumferentially proximally and distally, entire esophagus transected proximally and distally removing the diseased segment, anastomosis performed by apposing the mucosal-submucosal layer, The muscularis layer is apposed but relief incisions may be required to reduce tension

Front 50

What can reduce post-operative tension on esophageal resection and anastomosis:

Back 50

standing martingale

Front 51

Patch grafting:

Back 51

longitudinal incision made through the muscularis layer, extending 3 cm proximal and distal, mucosa incised after passage of NGT, strip of brachio- or sternocephalicus muscle separated from belly of the muscle but not transected proximally or distally, edge of submucosa-mucosa, and muscularis layers are sutured to the graft

Front 52

Management of esophageal fistulas:

Back 52

establishment of ventral drainage and elevating food and water to limit loss

Front 53

Types of esophageal diverticula:

Back 53

traction or true, pulsion or false

Front 54

Development of traction diverticula:

Back 54

contraction of periesophageal scar tissue and outward traction or tenting of all layers of the esophagus

Front 55

Causes of transction diverticula:

Back 55

esophagostomy sites, wounds allowed to heal by second intension, or after luminal penetration with leakage and secondary inflammation or abscessation

Front 56

Development of a pulsion or false diverticulum:

Back 56

protrusion of the mucosa-submucosa through a defect in the muscularis layer

Front 57

Causes of pulsion diverticula:

Back 57

fluctuations in esophageal intraluminal pressure, overstretch damage to esophageal muscle fibers after impaction, and external trauma

Front 58

Treatment of pulsion diverticula:

Back 58

diverticulectomy (resection of mucosa-submucosal sac) or inversion of the sac followed by reconstruction of layers

Front 59

When is diverticulectomy chosen?

Back 59

mucosal sac is very large and the neck of the diverticula is very narrow

Front 60

Megaesophagus:

Back 60

dilation and muscular hypertrophy of the esophagus oral to a constriction

Front 61

Types of megaesophagus:

Back 61

congenital ectasia (dilation of unknown origin), achalasia (failure of the distal esophagus to relax because of neural dysfunction) and secondary to vascular ring anomalies

Front 62

Complications of esophageal surgery:

Back 62

dehiscence and stricture, laryngeal hemiplegia, or carotid artery rupture and complication of esophageal disease such as acid-base and electrolyte alterations

Front 63

Why do acid-base and electrolyte alteration occur?

Back 63

loss of saliva

Front 64

What acid-base and electrolyte abnormalities usually occur?

Back 64

hyponatremia, hypochloremia, transient metabolic acidosis which progresses to metabolic alkalosis

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