Acute abdomen Flashcards
What is acute abdomen?
This refers to the rapid onset of severe symptoms that may indicate potentially life-threatening intra-abdominal pathology that requires urgent surgical intervention.
Clinical features of acute abdomen
Abdominal pain is usually a feature, but a pain-free acute abdomen can occur, particularly in older people, children, and the immunocompromised, and in the last trimester of pregnancy.
Acute abdominal pain is a frequent presentation in the emergency department.
Pain may:
Be located in any quadrant of the abdomen
Be intermittent, sharp or dull, achy, or piercing
Radiate from a focal site
Be accompanied by nausea and vomiting.
Who can present atypically with acute abdomen?
Older people
Pregnant women
Why do older people present atypically?
Central and peripheral nervous systems are affected by ageing.
Older people usually have more long-standing comorbidities than younger adults.
Older patients are also at higher risk for more severe disease due to decreased immune function.
Why do pregnant women present atypically?
The enlargement of the uterus, which displaces and compresses intra-abdominal organs, and the laxity of the abdominal wall makes it difficult to localise pain and can blunt peritoneal signs.
Causes of acute abdomen
Abdominal sources of acute abdomen are (in order of more common to less common):
- Intestinal obstruction
- Peritonitis secondary to infection (e.g., pelvic infection, appendicitis).
- Haemorrhage (e.g., ectopic pregnancy, ruptured aortic aneurysm)
- Ischaemia (e.g., ovarian torsion, mesenteric ischaemia)
- Processes associated with contamination by gastrointestinal contents (e.g., perforated duodenal or gastric ulcer).
How should you manage peritonitis?
This is a surgical emergency. Patients should be taken to the operating room for exploration without waiting for or performing diagnostic studies, as this would delay definitive care. Inflammatory conditions (e.g., diverticulitis, pancreatitis, and cholecystitis) and vascular processes (e.g., aortic dissection or ruptured abdominal aortic aneurysm) may also exhibit the same symptoms as peritonitis
Causes of intestinal obstruction
Adhesions are the most common cause of obstruction in industrialised countries.
Incarceration of hernias the second leading cause; hernia incarceration is the most common cause of bowel obstruction in patients without prior abdominal surgery.
Volvulus
Gallstones
Intussusception
Less common causes include congenital anatomical abnormalities, gastrointestinal neoplasm, and inflammatory bowel disease.
Inflammatory causes of acute abdomen
Inflammatory causes may include: Cholecystitis Appendicitis Acute pancreatitis Acute diverticulitis Meckel diverticulitis.
Ulcerative colitis and Crohn’s disease may present with abdominal pain secondary to the inflammatory process or due to the complication of obstruction.
Perforation causes of acute abdomen
Perforation can be a complication of duodenal and gastric ulcers. Oesophageal perforation (Boerhaave's syndrome) and Mallory-Weiss tear result in oesophageal laceration and gastrointestinal haemorrhage.
Gynaecological causes of acute abdomen
Females of childbearing age presenting with an acute abdomen should always have a pregnancy test to rule out an ectopic pregnancy.
Other pathologies involving the female reproductive organs include:
Ruptured ovarian cyst
Ovarian torsion
Pelvic inflammatory disease
Endometriosis.
Vascular causes of acute abdomen
Vascular pathologies may result in intra-abdominal haemorrhages such as abdominal aortic dissection, ruptured aortic aneurysm, and ruptured splenic artery aneurysm.
Ischaemic causes include acute mesenteric ischaemia and infarction, ischaemic colitis, splenic infarct. Vaso-occlusive episodes in sickle cell crises also can present with abdominal pain.
Budd-Chiari syndrome involves hepatic venous outflow obstruction and the abdominal pain may present with hepatomegaly and ascites.
Abdominal wall haematoma may occur spontaneously or secondary to trauma, exercise, coughing, or a procedure.
Infective causes of acute abdomen
Infective processes may involve intra-abdominal organs or structures such as the liver (hepatic abscess or hepatitis), and the gastrointestinal tract (gastroenteritis, infectious colitis, typhlitis [neutropenic enterocolitis])
Psoas abscess is more commonly due to a tuberculous abscess, which has extended from the lumbar vertebra into the psoas muscle.
Fitz-Hugh Curtis syndrome, a complication of pelvic inflammatory disease, comprises right upper quadrant abdominal pain associated with perihepatitis.
Metabolic causes of acute abdomen
Metabolic causes of acute abdomen include uraemia, diabetic ketoacidosis, Addisonian crisis, and hypercalcaemia.
Inherited metabolic disorders include acute intermittent porphyria and hereditary Mediterranean fever.
Toxic causes of acute abdomen
Heavy metal poisoning may be caused by medical/environmental/occupational exposure to, for example, mercury, lead, or arsenic.
Narcotic withdrawal from opioids may result in abdominal cramping pain.
