9. GI Emergencies Flashcards
What is peritonitis?
Inflammation of the serosal membrane that lines the abdominal cavity
How does peritonitis occur?
Peritoneal cavity usually sterile
Can happen spontaneously (primary) or by breakdown of peritoneal membranes leading to foreign substances entering cavity (secondary)
What is primary peritonitis?
Spontaneous bacterial peritonitis is an infection of ascitic fluid that cannot be attributed to any intra-abdominal, ongoing inflammatory, or surgically correctable condition
Most commonly seen in patients with end stage liver disease
What are the symptoms of primary peritonitis?
Abdominal pain, fever, vomiting
How is primary peritonitis diagnosed?
By aspirating ascitic fluid - neutrophil count >250 cells/mm^3
What is secondary peritonitis?
As a result of an inflammatory process in the peritoneal cavity secondary to inflammation, perforation or gangrene of an intra-abdominal or retroperitoneal structure
What are common causes of secondary bacterial peritonitis?
Peptic ulcer disease (perforated)
Appendicitis (perforated)
Diverticulitis (perforated)
Post surgery
What are some non bacterial causes of secondary peritonitis?
Tubal pregnancy that bleeds Ovarian cyst (ruptured)
What is the clinical presentation of peritonitis?
Abdominal pain
May come on gradually or acutely
Diffuse abdominal pain is common in perforated viscera
Patients often lie very still
What are the treatment approaches for peritonitis?
Control the infectious source - surgery
Eliminate bacteria and toxins - antibacterial therapy
Maintain organ system function - intensive care
What is a bowel obstruction?
Is a mechanical or functional problem that inhibits the normal movement of gut contents
Can affect large and small intestine
What are the common causes of bowel obstruction in children?
Intussusception
Intestinal atresia
What are some common causes of bowel obstruction in adults?
Adhesions
Incarcerated hernias
What is intussusception?
When one part of the gut tube telescopes into an adjacent section
Can extend quite far
When lymphatic and venous drainage is impaired, you get oedema which can lead to infarction
What are possible lead points in intussusception?
Meckel’s diverticulum
Enlarged lymph node
What is the classical presentation of intussusception?
Abdominal pain
Vomiting
Haematochezia
What is the treatment for intussusception?
Air enema
Surgery
What can cause small bowel obstruction?
Intra-abdominal adhesions
Hernias - incarcerated groin hernias most common
Crohn’s - repeated episodes of inflammation/healing causes narrowing
What are the symptoms of small bowel obstruction?
Nausea and vomiting (bilious) - early
Abdominal distension, absolute constipation - late
What are adhesions?
Abnormal fibrous bands between organs or tissues or both in the abdominal cavity that are normal separated
Greater omentum involved in 80%, bowel in 50%
How is small bowel obstruction diagnosed?
History - intermittent abdominal pain (3-5mins), cramps
Physical examination - abdominal distension, increased/absent bowel sounds, presence of hernia
Imaging - central position of bowel, bowel distension >3cm
What are the common causes of large bowel obstruction?
Colon cancer
Diverticular disease
Volvulus - sigmoid, Caesar
What are the symptoms of large bowel obstruction?
Often appear gradually if caused by cancer but abrupt with volvulus Change in bowel habit (cancer) Abdominal distension Cramps abdominal pain Nausea/vomiting
What is a volvulus?
Part of colon twists around its mesentery
Most common in sigmoid colon and cecum
Results in obstruction
Can result from overloaded sigmoid colon (constipation)
Caecal volvulus results in small and large bowel obstruction
What is acute mesenteric ischaemia?
Symptomatic reduction in blood supply to the GI tract
More common in females and if you have a history of peripheral vascular disease
What are the most common causes of acute mesenteric ischaemia?
Acute occlusion by arterial embolism in superior mesenteric artery
Non-occlusive mesenteric ischaemia - low cardiac output
Mesenteric venous thrombosis - systemic coagulopathy, malignancy
What are the symptoms of acute mesenteric ischaemia?
Non-specific
Abdominal pain is disproportionate to clinical findings - classically comes on 30 mins after eating (lasts for 4 hours)
Nausea and vomiting
Pain left sided
What investigations are done in acute mesenteric ischaemia?
Blood tests - metabolic acidosis/increased lactate levels
Erect chest x-ray (to check for perforation)
CT angiography
What is the treatment for acute mesenteric ischaemia?
Surgery - resection of ischaemic bowel, bypass graft
Thrombolysis/angioplasty
Mortality is high
What can cause upper GI bleeding?
Peptic ulceration
Oesophageal varices
How are oesophageal varices treated?
Banding
If banding does not work, TIPS (transjugular intrahepatic portosystemic shunt)
Drugs - terlipressin (reduces portal venous pressure)
What is a trans jugular intrahepatic portosystemic shunt?
An expandable metal is placed within the liver
Bridges the portal vein to an hepatic vein
Decompressed the portal vein pressure
Reduction in variceal pressure
Reduction in ascites
What is an abdominal aortic aneurysm?
Permanent pathological dilation of the aorta with a diameter >1.5 times the expected
Usually due to degeneration of the media layer of the arterial wall (elastin and collagen)
Most infrarenal
What are the risk factors for AAA?
Male
Inherited risk
Increasing age
Smoking
What are the different types of AAA?
Suprarenal
Pararenal
Juxtarenal
Infrarenal
If an AAA is compressing other nearby structures, what symptoms may the patient have?
Stomach (nausea), bladder (urinary frequency), vertebrae (back pain)
What is the usual presentation of ruptured AAA?
Abdominal pain Back pain Pulsation abdominal mass Transient hypotension Sudden cardiovascular collapse
How is a AAA diagnosed?
Physical examination - pulsatile abdominal mass
Ultrasonography
CT
Plain x-rays - calcification
What is the treatment for AAA?
Smoking cessation
Hypertension control
Surveillance >5.5cm refer to vascular surgeon
Surgery- endovascular repair, open surgical repair
