Peritonitis Flashcards
What is peritonititis?
- Inflammation of the peritoneum
- Acute vs chronic
- Septic vs aseptic
- Primary vs secondary
Name some of the causes of GI perforation?
- Inflammatory or ischaemic
- Chemical: peptic ulcer disease, foreign body
- Infection: diverticulitis, cholecystitis, meckels diverticulum
- Ischaemia: mesenteric, obstrcting lesions
- Toxic megacolon
- Traumatic
- Iatrogenic: surgery
- Penetrating or blunt trauma
- Direct rupture: vomiting leaading to oesophageal perforation
What are the clinical features of GI perforation?
- Pain
- Rapid onset, sharp
- Associated malaise, vomiting, lethargy
- Features of peritonism (rigid)
Describe the investigations which should be performed in someone with a suspected perforation?
- FBC, G&S, WCC, CRP
- Urinarlysis
- CXR
- Free air under diaphragm
- CT scan (gold standard)
- Confirms free air presence and suggests a location
- AXR:
- Rigler’s sign
- Psoas sign
What is Rigler’s sign?
- AXR
- Both sides of the bowel wall can be seen due to free intra-abdominal air acting as an additional contrast

What is psoas sign?
- AXR
- Loss of sharp definition of the psoas muscle border secondary to fluid in the retroperitoneum
Describe the management of a GI perforation?
- Broad spectrum antibiotics
- Nil by mouth + NG tube
- Surgery for repair and contamination control
Describe the key aspects of surgical intervention for a GI perforation?
- Identification and management of underlying cause
- Management of perforation
- Repair perforated peptic ulcer with an omental patch
- Resect a perforated diverticulae via Hartmanns procedure
- Thorough washout
What are the most important complications of a GI perforaiton?
- Infection
- Peritonitis
- Sepsis
- Haemorrhage
What is the most common type of peritonitis?
Acute suppurative peritonitis secondary to visceral disease
Describe the possible features of Chronic peritonitis secondary to peritoneal dialysis?
- Abdominal pain
- Ascites
- Obstruction due to matting of the bowel from dense adhesions
Treatment for Chronic peritonitis seconary to peritoneal dialysis?
- Removal of dialysis catheter
- Drainage of local fluid collections under US guidance
Describe Aseptic peritonitis?
- From chemical or foreign body irritants
- Often followed by secondary bacterial peritonitis
Chemical causes of aseptic peritonitis?
- Bile
- Blood
- Urine
- Gastric contents
- Meconium
Foreign body causes of aseptic peritonitis?
- Talc
- Starch
- Cellulose
Describe the management of peritonitis?
- Deal with underlying cause
- eg repair perforation, resect infarcted bowel
- Replace extracellular fluid
- NG tube to prevent further vomiting
- Antibiotic over for all those with established seondary peritonitis
Describe Primary peritonitis?
- Rare
- E. coli is most common cause
- Access through gut wall of distal blood-borne spread
Features of primary peritonititis?
- Abdominal tenderness
- Fever
- Leucocytosis
- Abdominal rigidity is uncommon
Describe Post-operative peritonitis?
- Effect of original disease or direct complication of surgery (anastomotic leak)
- Suspect if:
- Persistent abdominal distension
- Development of vomiting after apparent return to normal
Why is the diagnosis of post-operative peritonitis often difficult?
- Patient is often on post-op analgesia so may not be in pain
- Pain or tenderness often attributed to surgical wound
- 48hr post-surgery period where bowel sounds are absent and the abdomen is distended
What is the gold standard for diagnosing post-operative anastomotic leaks?
Contrast enhanced CT
Management of post-operative peritonitis?
- Fluid and electrolyte replacement
- Nasogastric suction
- Broad spectrum antibiotics
- Consider need for reoperation
Signs of SBP?
- Fever
- Abdominal pain
- Rebound tenderness
- Absent bowel sounds
- Evidence of cirrhosis and ascites
How is SBP diagnosed?
- Diagnostic paracentesis
- Cloudy fluid
- Neutrophil count >250x106/L
- Culture of fluid
Most common cause of SBP?
Enteric E. coli
Management of SBP?
- Broad spectrum antibiotics
- Cefotaxime
- Recurrence risk reduced with prophylactin quinolones (ciprofloxacin)