Chemical esophageal injuries

Question 1

Is an alkaline chemical or an acidic chemical more likely to cause a severe esophageal injury?

Answer 1

Alkaline. Chemicals with pH >11, such as liquid lye or button batteries. The high viscosity leads to slow transit time and prolonged exposure with rapid deep tissue penetration. This leads to liquefactive necrosis.

Question 2

Why does acid ingestion result in less severe injury?

Answer 2

Because coagulation necrosis creates eschar that limits progression of injury

Question 3

Should stomach contents be diluted after ingestion of caustic material?

Answer 3

No, this can cause emesis and result in further damage and reexposure to same caustic elements, leading to progression of injury.

Question 4

After ingestion of a caustic agent, should measures be made to neutralize the corrosive agent? Should an NG tube be passed on arrival?

Answer 4

No. This can lead to an exothermic reaction, that may further injure the surrounding tissue. An NG tube should not be placed blindly and are contraindicated.

Question 5

What are the indications for endoscopy after caustic material ingestion?

Answer 5

Stridor, symptomatic children (vomiting/drooling), oropharyngeal burns and all intended suicidal ingestions

Question 6

When should an endoscopy be performed for the evaluation of caustic esophageal injuries and why?

Answer 6

Within the first 12 to 24 hours. iatrogenic perforations often occur in a delayed fashion on the 2nd or 3rd day after injury; when burn weakens with friable granulation tissue.

Question 7

What is the appearance of a grade I caustic injury on endoscopy?

Answer 7

Mucosal edema and hyperemia (represents superficial mucosal burn)

Question 8

What is the appearance of a grade IIa caustic injury on endoscopy?

Answer 8

Patchy ulcerations, exudate and slough (represents transmucosal injury)

Question 9

What is the appearance of a grade IIb caustic injury on endoscopy?

Answer 9

Circumferential injury (represents transmucosal injury)

Question 10

What is the appearance of a grade III caustic injury on endoscopy?

Answer 10

Deep ulceration, black or gray discoloration, full thickness necrosis, thrombosed submucosal vessels(represents transmural injury and peri-esophageal or peri-gastric extension)

Question 11

Which grade injury is likely to develop stricture?

Answer 11

Grade IIb (>70%) and all Grade III progress to stricture formation.

Question 12

Why should endoscopy be limited to only assess site of maximal injury?

Answer 12

To minimize risk of perforation and provide evaluation for directed therapy

Question 13

Aside from early endoscopy, what comprises the work up of caustic ingestion?

Answer 13

Contrast swallow with gastrograffin (water soluble), followed by thin barium.

Question 14

What is the management of mild esophageal injury (grade I and IIa)?

Answer 14

Observation, diet advancement over 24 to 48 hours, and a follow up contrast study at 3 weeks to r/o stricture formation.

Question 15

What is the management of grade IIb and III injuries?

Answer 15

Observation at a minimum of 48 hours to one week, with parenteral nutrition. Gastrostomy tubes may be placed for severe injuries for enteral conduit and for retrograde dilatations. Antibitotics to cover oropharyngeal flora for 3 weeks, H2 blockers

Question 16

Why are patients placed on H2 blockers for treatment of caustic ingestion with grade II-III injuries?

Answer 16

To decrease acid reflux secondary to esophageal dysmotility and theorectically decrease stricture rates.

Question 17

When does a delayed perforation occur post ingestion of caustic agents resulting in esophageal injury?

Answer 17

1-2 weeks

Question 18

How is severe esophageal injury (full thickness/perforation) treated?

Answer 18

Esophagectomy, cervical esophagostomy, feeding gastrostomy and jejunostomy, or esophagectomy with transhiatal gastric transposition

Question 19

What is the mortality in delayed resection in setting of third degree burns and perforation?

Answer 19

100%

Question 20

Complication of caustic ingestion of battery, usually with the first week after injury?

Answer 20

Tracheoesophageal fistula

Question 21

What are the options for esophageal replacement?

Answer 21

Colonic interpostion graft, gastric tube or free jejunal grafts

Question 22

Which esophageal replacement technique is the most widely used?

Answer 22

Colonic interposition graft

Question 23

What are the advantages and disadvantages of colonic interposition graft?

Answer 23

Reliable blood supply and similar anatomic reservoir but may develop redundancy and stasis as late complications

Question 24

What are the major disadvantages of a gastric esophageal reconstruction?

Answer 24

May be of inadequate length, and pyloroplasty may lead to dumping symptoms.

Question 25

Why should grade IIb and III injuries after caustic ingestion have long term annual follow up?

Answer 25

The development of strictures and the high incidence of cicatrical cancer.

Question 26

What is the timing of dilatation for esophageal strictures s/p caustic ingestion and why?

Answer 26

> 4 weeks because dilations earlier have significant risk of iatrogenic perforations.

Question 27

How are intractable and persistent strictures managed?

Answer 27

Surgical intervention. Intractable strictures may require bypass, resection or esophagoplasty. Persistent strictures will require esophagectomy

Question 28

What type of cancer is associated with strictures due to caustic ingestion?

Answer 28

Squamous cell carcinoma

Question 29

How often should dilatation be performed?

Answer 29

Bougienage should be performed on alternative weeks, aming for passage of a 46 to 50 Fr dilator in adults (and 32 to 36Fr dilator in toddlers).