9b.) GI Emergencies Flashcards
What is peritonitis?
Inflammation of the serosal membrane that lines the abdominal cavity (the peritoneum)
Peritoneal cavity is usually a sterile environment; true or false?
True
Describe how patients with peritonitis will often lie
Lie very still, any movement is painful
State and describe the two types of peritonitis
- Primary: inflammation due to spontaneous bacterial invasion of peritoneum- causses infection of the ascitic fluid in peritoneum
- Secondary: inflammation due to foregin substance entering peritoneal cavity perforation or gangrene of intra-abdominal or retroperitoneal structure (note: can have bacterial and non-bacterial causes)
Who is primary peritonitis commonly seen in?
Patients with end stage liver disease (cirrhosis)
Describe how ascites form in patients with end stage liver disease (cirrhosis)
- Cirrhosis compresses veins in liver
- Causes portal hypertension which increases pressure in veins draining gut- increases hydrostatic pressure of veins
- Cirrhosis also causes decreased liver function leading to hypoalbuminaemia- decreases oncotic pressure in veins
- Net movement of fluid down pressure gradient out of veins and into peritoneum
- Problem exacerbated by RAAS responding to decreased intravascular volume
Describe how someone with peritonitis might present
- Abdo pain
- Can come on gradually or acutely (if acute likley to be perforated viscera)
- Will lie still with knees flexed
- Shallow breathing
- Fever
- Vomitting
- Distension & swelling
How do you diagnose primary peritonitis?
- Aspirate ascitic fluid
- Neutrophil count >250cells/mm^3
State some common causes of secondary bacterial peritonitis
- Peptic ulcer disease- ulcer perforated
- Perforated appendix
- Diverticulitis- divertuclum perforated
- Post surgery
State some comon causes of secondary non-bacterial peritonitis
Usually caused by blood entering peritoneal cavity
- Tubual pregnancy that bleeds (remember peritoneal cavity is not closed in females so blood can travel from tubes to peritoneum)
- Ovarian cyst
Secondary peritonitis can be bacterial or non-bacterial; explain the difference
- Bacterial: caused by bacteria which often enters due to lack of integrity of GI system
- Non-bacterial: often due to blood entering peritoneal cavity (blood is highly irritant to peritoneal cavity)
Describe the typical presen
Describe how we treat peritonitis (3)
- Control infectious source (e.g. surgery if perforation)
- Eliminate bacteria using antibiotics
- Maintain organ system function
Define bowel obstruction
Mechanical or functional problem that inhibits the normal movement of gut cotents; it can affect small or large intestine
Bowel obstruction only affects the elderly; true or false?
FALSE- bowel obstruction can affect all ages
State the 3 most common causes of bowel obstruction in paediatrics
- Meconium ileus: the meconium is blocking the ileum
- Intestinal atresia: congenital malformation in which segment of intestine failed to develop properly hence causing a complete blockage or lack of continuity e.g. pyloric stenosis
- Intussusception: part of intestine folds into segment next to it
State 2 most common causes of bowel obstruction in adults
- Post op adhesions
- Incarcerted hernias: hernia that cannot be moved back in place- pinchign action can obstruct bowel (see image)
Describe intussusception, include:
- What occurs
- Causes
- How far can intussusception extend
- Complications
- Symptoms
- Treatment
- One part of gut tube telescopes/folds into an adjacent section
- Cause not well known, think:
- Potential motility issues
- ‘Lead point’: mass (could be lymph node, Meckels diverticulum etc..) that precipitates telescoping action
- Extend as far as prolapsing out of rectum
- Complications:
- Impair lymphatic & venous drainage -> oedema
- Oedema can impair arterial supply -> infarct
- Symptoms:
- Abdo pain
- Vomitting
- Haematochezia (rectal bleeding)
- Mucus
- Treatment:
- Air enema
- Surgery
Describe how someone with small bowel obstruction may present
Often start suddenly:
- Nausea/vomitting (bilioius) = early symptom
- Peri-umbilical pain
- Abdo distension
- High pitched bowel sounds on auscultation
- Absolute constipation= late symptom
State 2 possible causes of small bowel obstruction
- Hernias
- IBD causing stenosis
Which population do large bowel obstructions typically affect?
Older generation
State some common causes of large bowel obstruction
- Colon cancer
- Diverticular disease- can lead to strictures
- Volvulus- sigmoid, caecal (loop of intestine twists around itself and it’s mesentery)
Most large bowel obstructions caused by cancer occur distal to what flexure?
Distal to splenic flexure
What imaging can we use to aid diagnosis of bowel obstruction?
CT
Abdominal x-ray
????
Describe how someone with large bowel obstruction might present
- Peri-umbilical or suprapubic pain
- Abdo distension
- Diarrhoea or constipation (early symptom)
- Nausea or vomitting (late symptom)
Describe volvulus, include:
- What it is
- Where it is most common
- Causes
- Consequences of caecal volvulus
- Part of colon twists around itself and its mesentery
- Most common in sigmoid colon (60%) and caecum
- Causes:
- Overloaded sigmoid colon (constipation) as extra mass elonages sigmoid meaning there is a relatively smaller mesenteric attachment
- Caecal volvulus leads to small and large bowel obstruction
Compare small and large bowel obstruction, consider:
- Age typically presents in
- Abdo pain
- Vomitting
- Constipation
- Small bowel- often younger
- Large bowel- often older age group (because causes of large bowel obstruction develop over time)
Which artery is most likely to be ruptured in a duodenal ulcer?
Gastro-duodenal artery as it lies behind first part of duodenum
What artery could a gastric ulcer in body of stomach erode into?
Splenic artery
Describe the path blood may take in oesophageal varices
What divides the greater sac into supracolic and infracolic regions?
Transverse mesocolon
What are intra-abdominal adhesions?
How do they form?
State another potential consequence of adhesions, besides bowel obstruction
- Abnormal fibrous bands of tissue between organs or tissues (e.g. can be between two sides of lumen) or both in the abdominal cavity connecting structures which are usually separated
- Damage to mesothelium causes capillary to leak leading to exudation of fibrinogen
- Secondary infertility
What does this image show?
Volvulus
“Coffee bean sign”
How can we determine which is the large and which is the small intestine?
- Left= small
- Right= large
Because….
- Small intestine lines should go all way across ‘plicae circulares’
- Large intestine lines shouldn’t go all way across ‘haustra’
- Small intestine central
- Large intestine at periphery
How can we treat oesophageal varices?
- Ligation: band around the bulging varices to prevent further blood going in and rupture. Varices evetnually fall off/drop off
- (if can’t control by ligation) Transjugular intrahepatic portosystemic shunt (TIPS): expandable metal placed in liver to bridge portal vein to hepatic vein to reduce portal pressure and hence reduce variceal pressure
- Vasopressin agonist to reduce portal venous pressure and pressure in varices e.g. terlipressin
Describe how a triple A (that hasn’t ruptured) may present
- Abdominal and back pain
- Symptoms due to compression of other structures e.g. nausea, urinary frequency
- Pulsatile mass in abdomen
Describe how a triple A that has ruptured may present
- Severe abdominal pain (+/- flank and groin pain)
- Back pain
- Pusatile abdominal mass
- Transient hypotension- syncope
- Rapid HR
- Shock
