GI Emergencies And Infection Flashcards
What connects the greater sac and lesser sac of the peritoneal cavity?
Foramen of Winslow.
What is peritonitis?
Inflammation of the serosal membrane that lines the abdominal cavity.
What causes primary peritonitis?
How is it diagnosed?
Infection of ascitic fluid in the peritoneal cavity. Occurs commonly in patients with end stage liver disease.
Diagnosed by aspirating ascitic fluid and testing for a neutrophil count greater than 250 cells per mm^3
What causes secondary peritonitis?
Inflammatory process within the peritoneal cavity secondary to inflammation, perforation or gangrene of an intraabdominal structure. Common after surgery or appendicitis.
What non bacterial causes are there for secondary peritonitis?
Ovarian cyst,
Tubal pregnancy,
Blood in the peritoneum (this is highly irritant).
How does peritonitis present?
How is it treated?
Abdominal pain,
Nausea and vomiting,
Fever.
Patients are often immobile and take shallow breaths.
Treated with antibiotics or surgery to control the source.
What is the most common cause of bowel obstruction in children?
Intussusception - part of the gut tube telescopes into an adjacent section.
What are the classic signs of intussusception?
How is it treated?
Abdominal pain, vomiting and haematochezia.
Treated with an air enema or surgery.
What presenting symptoms may help indicate a small bowel obstruction?
What is the most common cause of this?
Nausea and bilious vomiting.
Intra-abdominal adhesions forming after surgery or damage to the mesothelium.
At what width is small bowel considered distended?
What about large bowel?
3cm.
6cm.
Which type of bowel obstruction is more common in the younger generation?
Small bowel obstruction.
What are common causes of large bowel obstruction?
Colon cancer,
Diverticular disease,
Volvulus of the sigmoid or caecum.
What is a volvulus?
What sign is typically seen on imaging?
Part of the colon that twists around its own mesentery, resulting in obstruction. Often occurs at the sigmoid colon as this has its own mesentery.
Coffee bean sign - distended bowel looks like a coffee bean.
What are plica circulares?
Full width bowel folds seen within the small bowel, often when it is distended.
What are the most common causes of acute mesenteric ischaemia?
Who is most at risk?
Arterial embolism of the superior mesenteric artery,
Low cardiac output,
Mesenteric venous thrombosis.
Most common in females and those with peripheral vascular disease.
How does acute mesenteric ischaemia commonly present?
How might it be diagnosed?
Excrutiating abdominal pain, disproportionate to clinical findings on examination, nausea and vomiting.
Blood tests for increased lactate levels, CT angiography and CXR to check for perforation.
How is acute mesenteric ischaemia treated?
What is the mortality rate?
Surgical resection of ischaemic bowel,
Thrombolysis,
Bypass grafts.
Mortality of approximately 70%.
How is a peptic ulcer defined?
Where are they most common?
Disruption of the gastric or duodenal mucosa that passes through the muscularis mucosa.
Common in duodenum, lesser curve and antrum.
What prehapatic, hepatic and post hepatic causes are there for oesophageal varices?
Prehepatic - portal vein thrombosis.
Hepatic - cirrhosis, schistosomiasis.
Post hepatic - hepatic vein thrombosis, right sided heart failure.
If oesophageal varices do not respond to ligation, what is the next step?
Transjugular intrahepatic portosystemic shunting (TIPS).
Bridges portal vein to hepatic vein, reducing variceal pressure.
Treatment with Terlipressin - lowers portal venous pressure.
How is abdominal aortic aneurysm defined?
Permanent pathological dilation of the abdominal aorta with diameter 1.5x expected of the segment, or approximately 3cm or more.
What are the four types of AAA?
Which is most common?
Suprarenal, Pararenal, Juxtarenal, Infrarenal (most common). Named in relation to renal arteries.
