GI Emergencies Flashcards
What is peritonitis?
Inflammation of the serosal membrane that lines the abdominal cavity
How does peritonitis occur if the peritoneal cavity is normally a sterile environment?
Primary: Spotaneous inflammation
Secondary: Breakdown of peritoneal membranes leading to foreign substances entering the cavity
What is spontaneous bacterial peritonitis? How do you diagnose it
Primary peritonitis often seen in patients with end stage liver disease → an infection of ascitic fluid that cannot be attributed to any intra-abdominal ongoing inflammation
Diagnosed by aspirating ascitic fluid, neutrophil count >250 cells/mm3
Explain how end stage liver disease leads to ascites
Cirrhotic liver has 2 main effects:
- Portal hypertension increases hydrostatic pressure in the capillary
- Decreased albumin production decreases oncotic pressure in the capillary
- Results in a net movement of fluid into the peritoneal cavity
What symptoms are associated with spontaneous bacterial periotnitis?
- Abdominal pain
- Fever
- vomiting
- Often mild
What are some of the common causes of secondary bacterial perionitis?
- Peptic ulcer disease (perforated)
- Appendicities (perforated)
- Diverticulitis (perforated)
- Post surgical (especially laproscopic)
What are some of the non-bacterial causes of secondary peritonitis?
- Tubal pregnancy (ectopic rupturing into peritoneal cavity → blood is highly irritant)
- Ovarian cysts
How does peritonitis present clinically?
-
Pain most common symptom
- may be gradual or acute
- diffuse if perforated into viscera
- Patients often lie very still wth shallow breathing and flexed knees to avoid making to pain worse
How would you treat peritonitis?
- Control the infectious source → surgery
- Eliminate bacteria and toxins → antibiotics
- Maintain organ system function → may admit to ICU
What are some of the common causes of bowel obstrucion in adults vs children?
Children:
- Intussusception
- Intestinal atresia
Adults:
- Adhesions
- Incarcerated hernias
What is intussusception?
When one part of the gut tube telescopes into an adjacent section
How would you treat bowel intusssusception?
- Air enema (pump air into recutm)
- Surgery if enema unsuccessful
In an intussusception, at what point would you get oedema?
As soon as the lymphatic and venous drainage is impaired
What are some of the symptoms of intussusception?
- Abdominal pain
- Vomiting
- Haemoatochezia
Where does Meckel’s diverticulum most commonly occur?
Located in the distal ileum, 2ft away from the ileocaecal valve
What is volvulus?
Where part of the colon twists on its mesentry, resulting in bowel obstruction, can result in infarct
Which artery is vulnerable to erosion by a peptic ulcer in the 1st part of the duodenum?
Gastroduodenal artery
Where does blood from oesphageal varices drain to?
Portal drainage: oesophageal veins drain into the left gastric vein and into the portal vein
Systemic drainage: oesophageal veins drain to azygous system, drains into superior vena cava
How would you treat oesophageal varices?
- Band Ligation
- If not controlled by band ligation insert a TIPS (transjugular inrahepatic portosystemic shunt)
- expandable metal placed in teh liver to bridge the portal vein and hepatic vein which decompresses portal vein pressure
What is an abdominal aortic aneurysm? How does it typically arise?
A permanent pathological dilation of the aorta with a diameter >1.5 times the expected AP diameter of that segment
Typically due to the degeneration of the elastin and collagen of the media layer of the arterial wall
In which location do most AAAs occur?
Infrarenal (90%)
What are the symtpoms of AAA?
Usually asymptomatic until acute expansion or rupture
Can cause symptoms by compressing nearby structures:
- nausea, urinary frequency and backpain
Usual presentation when ruptured:
- abdominal pain +/- flank/ groin pain
- back pain
- pulsatile abdominal mass
- transient hypotension → syncope
- sudden cardiovascular collapse
