Bowel Perforation Flashcards
Where can bowel perforation occur?
Any location from the oesophagus to the rectum
What is the most common causes of bowel perforation?
Peptic ulcers (gastric / duodenal) & Sigmoid diverticulum
What are inflammatory causes of perforation?
Chemical
- Peptic ulcer disease
- Foreign body (e.g. battery or caustic soda)
Infection
- Diverticulitis
- Cholecystitis
- Meckel’s Diverticulum
Colitis
- Toxic megacolon (e.g. C. diff, Ulcerative Colitis)
What are ischaemic causes of bowel perforation?
- Mesenteric Ischaemia
- Ischaemia and necrosis due to obstruction
Give examples of traumatic causes of bowel perforation.
Iatrogenic
- Recent surgery (including anastomotic leak)
- Endoscopy / overzealous NG tube insertion
Penetrating or blunt trauma
- Shear forces from acceleration-deceleration
- High forces over small surface area (e.g. a handle bar)
Direct rupture
- Excessive vomiting leading to oesophageal perforation (Boerhaave Syndrome)
What are symptoms of bowel perforation?
- Pain
- Rapid onset
- Sharp in nature
- Symptoms of systemic illness
- Malaise
- Vomiting
- Lethargy
What are the signs of bowel perforation, found on examination?
- Patients will look unwell
- Features of sepsis
- Tachycardia, Tachypnoea, High temp, Low BP
- Features of peritonism (Localised / Generalised)
- Rigid abdomen
- Staying very still
What is implied if a patient is peritionitic throughout their abdomen & what action needs to be taken?
This implies generalised contamination & they will almost always need urgent surgery.
What is the presentation of thoracic perforation, such as in oesophageal rupture?
Symptoms
-
Pain
- From chest or neck
- May radiate to the back
- Worse on inspiration
- Associated vomiting and respiratory symptoms.
Signs
- Signs of pleural effusion on auscultation and percussion
- Palpable crepitus potentially
What are important differentials to consider with a presentation of bowel perforation?
- Acute pancreatitis
- Myocardial infarction
- Tubo-ovarian pathology
- Ruptured aortic aneurysm
What lab tests would you order when investigating a suspected case of bowel perforation?
- Baseline blood tests, including G&S.
- Raised WCC and CRP are common features
- Dependent on timing and degree of contamination
- Amylase often mildly elevated in perforation (although non-specific)
- Urinalysis
* To exclude both renal & tubo-ovarian pathology.
What imaging may you order when investigating a suspected case of bowel perforation?
- Erect chest radiograph (eCXR)
- Can show free air under the diaphragm
- Pneumomediastinum / widened mediastinum may also be present if the perforation is thoracic in origin.
- CT (Gold standard for diagnosis of any perforation)
- To confirm any free air presence
- To suggest a location of the perforation & a possible underlying cause
What is Rigler’s sign?
Also known as the double-wall sign:
It’s a sign of pneumoperitoneum seen on AXR when both sides of the bowel wall can be seen, due to free intra-abdominal air acting as an additional contrast.
What is Psoas sign?
Loss of the sharp delineation of the psoas muscle border, secondary to fluid in the retroperitoneum.
What is the initial management of a patient with bowel perforation?
Warrants early assessment, rapid diagnosis and early definitive treatment:
- Start broad spectrum antibiotics early
- NBM
- Consider NG tube
- IV fluids and analgesia
- Move onto highly individualised management, taking into account the site of perforation and patient factors
