gastric perf

Question 1

definition of gi perf

Answer 1

full thickness loss of bowel wall integrity that results in perforation peritonitis

Perforation of the wall of the GI tract with spillage of bowel contents.

Question 2

path of gi perf

Answer 2

Most perforations of the large bowel occur in the sigmoid colon, as this is a common site of diverticular disease and colorectal cancer.

In most cases a pericolic abscess develops, followed by perforation.

approx 15% of cases occur in the caecum following distal obstruction with a competent ileocaecal valve, as this is the most vulnerable part of the colon (Laplace’s Law).

The most frequent site of perforation of duodenal ulcers is in the anterior wall.

In 80% of Boerhaave’s syndrome there is a longitudinal tear in the left posterolateralwall of the distal oesophagus.

Question 3

aetiology gi perf

Answer 3

ulcerative/erosive disease

• peptic ulcer disease
  
  • most common cause of stomach and duodenal perforation
  • duodenal ulcers of anterior wall are more likely to perforate
• malignancy
• IBD

infections

• diverticulities
• acute appendicites
• thyphoid
• GI TB
• toxic megacolon

bowel ischemia

• bowel obstruction ie adhesions, volvulus, malignancy
• acute mesenteric ischemia

trauma

• penetrating trauma - stab injury/iatrogenic
• blunt abdo trauma

foreign body ingestion

drug induced - NSAIDs, glucocorticoids, cocaine

radiation to the abdominopelvic or lower thoracic region

post renal transplant

Question 4

rf gi perf

Answer 4

Gastroduodenal: Use of NSAIDs, steroids. Curling’s ulcer is associated with severe trauma, surgery or burns.

Question 5

large bowel perf

Answer 5

most common: diverticulitis and colorectal carcinoma (80%)

perforated appendix is common complication of appendicitis

volvulus

UC (toxic megacolon)

trauma

radiation enteritis and complications of post-op anastomotic dehiscence or colonoscopy

Question 6

gastroduodenal perf

Answer 6

most common: perforated duodenal or gastric ulcer

more rarely gastric carcinoma

Question 7

small bowel perf - rare

Answer 7

trauma

infection (typhoid, TB)

crohn’s

lymphoma

vasculitis

radiation enteritis

Question 8

oesophagus perf

Answer 8

Boerhaave’s syndrome is rupture following forcible vomitingagainst a closed glottis

Iatrogenic perforation rarely occurs during OGD but more commonly when dilatation of benign or malignant strictures is being carried out.

Question 9

epi gi perf

Answer 9

incidence depends on the cause

Presentation with abdominal pain due to bowel perforation is, however, a relatively common and potentially life-threatening emergency.

Question 10

sx of gi perf

Answer 10

sudden onset abdominal pain and distension

nausea, vomiting, obstipation (severe or complete constipation)

fever

involuntary guarding

rebound tenderness

rigid

Question 11

hx of perf peptic ulcer

Answer 11

sudden onset of intense stabbing pain

followed by diffuse abdo pain and distension (beginning peritonitis)

referred pain to shoulder due to irritation of the diaphragm

history of recurrent epigastric pain

chronic use of NSAIDs

perforation of chronic ulcers might only cause mild symptoms

Question 12

hx perf diverticulitis

Answer 12

constipation

previous LLQ pain

Question 13

localisation of pain in perf

Answer 13

diffuse in pts with free intraperitoneal perforation

localised RLQ - contained perforated appendicities

Localised LLQ - contained perforated diverticulitis

Question 14

large bowel perf hx

Answer 14

presents with abdominal pain due to peritonitis

ruptured AAA should be considered when presented with sudden onset abdo pain and shock

Question 15

gastroduodenal perf hx

Answer 15

sudden onset severe epigastric pain, then more generalised

worse on movement

in elderly the presentation might not be as acute

• epigastric discomfort
• or in gastric malignancy of pain, weight loss or vomiting

Question 16

oesophageal perf hx

Answer 16

sever pain following an episode of violent vomiting

endoscopic perforations are seen at time of procedure

or pain in the neck or chest and dysphagia develops soon after

Question 17

signs GI perf

Answer 17

rigidity, quiet bowel sounds, guarding - classical features of peritonitis. GENERALISED peritonitis in an unwell pt usually indicates that an abdominal viscus has perforated

tachycardia

tachypnea

hypotension

(Perforation peritonitis typically results in third-spacing of fluid and paralytic ileus, which can cause significant hypovolemia. In patients with sepsis, hypotension may signify the onset of septic shock.)

signs of peritonitis or shock, pyrexia, pallor, dehydration

decreased or absent bowel sounds (due to paralytic ileus)

loss of liver dullness on RUQ percussion (because of presence of air between the diaphragm and the liver)

In oesophageal perforations there may be SC emphysema or signs of a hydro- or pneumothorax.

Question 18

ix perf

Answer 18

U&E

LFT
amylase - level may be raised in perforations

clotting

blood count - neutrophilic leukocytosis

raised blood urea nitrogen, and creatinine - indicate prerenal kidney injury due to prolonged hypovolaemia and hypotension which accompanies perforation peritonitis

blood gas analysis - lactic acidosis (in ischemic perforation)

Question 19

imaging perf

Answer 19

erect CXR - air under the diaphragm and/or between the liver and the lateral abdominal wall, which rises up from the abdomen as the pt sits for the exam

AXR upright and supine - can show abnormal gas shadows in tissues or in the bowel wall, alternatively a lateral decubitus film can demonstrate intraperitoneal gas

gastrograffin swallow - for suspected oesophageal perforations. Alternatively, any coexisting pleural effusion aspirate would test positive for amylase.

[[CT abdo with IV contrast

indications - acute, non-localised abdominal pain

findings - pneumoperitoneum, signs of perforated bowel (loss of bowel wall continuity, localised mesenteric fat stranding)

IV contrast is preferred if bowel perforation is suspected. If oral contrast must be used, a water-soluble contrast agent is preferred

indication for XR - pts with contraindications to contrast

US abdo

• preferred in pts with CI to radiation eg in pregnancy
• findings: pneumoperitoneum, localised fluid collection, localised thickening of bowel segment ]] - amboss

Question 20

resus mx perf

Answer 20

vital preop with treatment of shock

oxygen

insert a cannula

perform emergency blood tests

administer IV normal saline - correction of fluid and electrolyte abnormalities

Give IV morphine and an anti-emetic

antibiotics - metronidazole, cefuroxime - organisms causing sepsis are likely to be normal bowel pathogens (are a mixture of Gram +ve, Gram –ve, and anaerobic bacteria, eg. Enterococcus , E. Coli, and Bacterioides, respectively.) . Cefuroxime is effective against both. Metronidazole is usually added because of its excellent anti-anaerobic cover.

urinary catheter

central line

Question 21

conservative mx perf

Answer 21

reserved for those that are a high anaesthetic risk (ASA 4 or 5)

NBM

high dose PPI

IV fluids

IV AB

NG tube and close monitoring

Question 22

surgery mx perf

Answer 22

laparotomy to repair the breach in the mucous membrane

bowel perforation is a surgical emergency - in some cases the clinical features are enough to warrant an emergency explorative laparotomy

large bowel laparotomy

• identification of the site of perforation and peritoneal lavage
• resection of the involved colon - usually as part of Hartmann’s procedure with formation of an end colostomy and closure of the distal stump or exteriorisation as a mucous fistula
• A localised perforation of the right colonmay allow resection and a primary anastomosis.
• In toxic megacolon of ulcerative colitis, a subtotal colectomy is performed with a terminal ileostomy and preservation of the rectal stump (allows future reconstruction of ileoanal pouch).

gastroduodenal laparotomy and peritoneal lavage

• the perforation is closed and an omental patch placed
• gastric ulceers should be biopsied (4 quadrant frozen section if possible) to examine for carcinoma
• Closure is more difficult than duodenal ulcers and Billroth I partial gastrectomy with gastroduodenal anastomosis can be done. Post-op: H. pylori eradication if positive.

oesophageal

• depends on the pathology and time of the presentation
• If occurs during dilation of a malignant stricture, coverage by an expandable stent may be possible.
• If spontaneous and<24h from onset, should be treated surgically using a left thoracotomy with pleural lavage and primary repair, or oesophagectomy.

Question 23

complications GI perf

Answer 23

peritonitis

bacteraemia

sepsis

multiorgan dysfunction

intra-abdo abscess

intra-abdo adhesions

subhepatic abscess

pyogenic liver abscess

pelvic abscess

postop complications

large and small bowel - peritonitis

oesophageal - mediastinitis, shock, overwhelming sepsis and death

Question 24

Px gi perf

Answer 24

Gastroduodenal: Higher morbidity and mortality in perforated gastric ulcers than duodenal; perforated gastric carcinomas have a very poor prognosis.

Large bowel: Untreated colonic perforation has a high risk of faecal peritonitis and death from septicaemia and multiorgan failure.