Perforated viscus Flashcards
What is perforated viscus?
Perforation of GI tract anywhere from upper oesophagus to the anorectal junction.
What is the most common cause of perforated viscus?
Peptic ulcers (gastric or duodenal) and sigmoid diverticulum
What are the inflammatory or ischaemic causes of perforated viscus?
Include examples of chemical, infectious, ischaemic causes.
Chemical:
- Peptic ulcer disease
- Foreign body (e.g. battery)
Infection:
- Diverticulitis
- Cholecystitis
- Meckel’s diverticulum
Ishchaemia:
- Mesenteric ischaemia
- Obstructing lesions (e.g. cancer, bezoar, faeces) leading to bowel distension & subsequent ischaemia and necrosis.
Toxic megacolon e.g. C.diff or ulcerative colitis
What are the traumatic causes of perforated viscus?
Recent surgery
Endoscopy/NG tube insertion
Penetrating or blunt trauma
Excessive vomiting leading to oesophageal perforation
What are the clinical features of viscus perforation?
Pain - rapid onset & sharp
Systemically unwell - malaise, vomiting, lethargy
Features of sepsis
Features of peritonism - localised or generalised (rigid abdomen)
Urgent surgery for generalised peritonism - implies contaminated everywhere
How do thoracic perforations (oesophageal rupture) present?
Pain - chest or neck pain radiating to the back
Pain worse on inspiration
Associated vomiting & respiratory symptoms.
Signs of pleural effusion possible on examination
What are the important differential diagnosis for perforated viscus?
Acute pancreatitis
Myocardial infarction
Tubo-ovarian pathology
Ruptured abdominal aortic aneurysm
Investigations: Which lab tests would you conduct?
Which common features are raised?
Acute abdomen patients require:
Routine baseline blood tests + group & save blood test
Urinalysis to exclude renal & tuba-ovarian pathology
Raised WCC and CRP
Amylase mildly raised in perforation
Investigation: Which imaging is needed to confirm the diagnosis?
Gold standard = CT scan confirming free air presence & location of the perforation (+ possible underlying cause)
A plain film erect chest X-ray - free air under diaphragm. Pneumomediastinum or widened mediastinum may iso be present if the perforation is thoracic.
Abdominal Xray (CT preferred):
- Rigler’s sign: both sides of the bowel wall can be seen, due to free intra-abdominal air acting as an additional contrast
- Psoas sign: loss of sharp delineation of the psoas muscle border, secondary to fluid in the retroperitoneum.
What sign are you looking for in imaging to confirm the diagnosis?
Air outside the GI tract
What is the initial management for suspected/early perforated viscus?
Early assessment & resuscitation, rapid diagnosis and early definitive treatment.
Broad-spectrum antibiotics started early especially in patients who need surgery for contamination
Patients should be nil by mouth + NG tube considered.
IV fluid and analgesia.
What is the surgical intervention for perforation?
Identify & manage underlying cause.
Repairing perforated peptic ulcer with an metal patch
Resecting a perforated diverticular e.g. via a Hartmann’s procedure.
(Hartmann’s procedure = surgical resection of the rectosigmoid colon with closure of the anorectal stump and formation of an end colostomy)
Thorough intra-operative washout.
Most patients with perforation treated surgically.
Who is selected for conservative management for perforated viscus?
Selected physiologically well patients without generalised peritonitis:
- Localised diverticular abscess/perforation with only localised peritonitis & tenderness ; no evidence of generalised contamination on CT
- Patients with a sealed upper GI perforation on CT without generalised peritonism
- Elderly frail patients with multiple co-morbidities, unlikely to survive surgery.
A size less than 5cm on CT scan is the cut off for conservative treatment. How are they treated?
Antibiotics alone
May get a guided percutaneous drainage
What are the complications of a GI perforation?
Infection (peritonitis & sepsis)
Haemorrhage
Delay in resuscitation and surgery = septic shock, multi-organ dysfunction and death.
Should be one of the first diagnosis considered in patients with abdominal pain