Stomach, Small and Large Bowel Flashcards
(34 cards)
4 cardinal symptoms of intestinal obstruction?
pain-colicky
absolute constipation- neither faeces nor flatus passed, obstipation= severe constipation due to obstruction
vomiting
abdominal distension
describe characteristics of mesenteric ischaemia?
acute abdominal pain occurs with sudden mesenteric artery occlusion causing bowel infarction
ptnt usually middle-aged, male smoker, with other signs of arterial disease e.g. IC, angina or previous MI.
also occurs with volvulus, and presents similarly to venous occlusion seen in pro-thrombotic conditions.
abdom pain prod in SLE and sickle cell disease may be related to mesenteric ischaemia.
what are the symptoms and signs of meckel’s diverticulitis indistiguishable from?
acute appendicitis
although pain and tenderness generally felt more towards centre of abdomen than RIF.
what is gastroenteritis usually caused by?
campylobacter or viral infection
how are diverticula thought to form?
disordered colonic peristalsis, which may be the result of constipation. Peristalsis in neighbouring colon segemnts causes high intraluminal pressure in between which may allow herniation of mucosa through bowel wall at points of wknesss e.g. where blood vessels enter.
why do the appendix and rectum not have diverticula?
have continuous longitudinal muscle layer
rather than taenia- colonic diverticula occur between antimesenteric taenia and the omental and free taenia, at site of b.vessel entry.
why might a diverticulum become inflamed?
thickened faecolith obstructs neck of diverticulum
symptoms of acute diverticulitis?
lower abdominal colic
followed by constant LIF pain
rebound tenderness and guarding result
complication of diverticula that carries a mortality of 50%?
perforation producing a faecal peritonitis
how does haemorrhage occur with diverticula?
neck of diverticulum sandwiched between a faecolith and a colonic b.vessel
CI to investigating diverticula with flexible sigmoidoscopy and colonoscopy?
acutely inflamed distal colon as bowel perforation may result
can also CT, and barium enema- good for diagnosis 6 wks following symptom resolution
tment of acute diverticulitis or diverticular mass?
antibiotics- BS, cephalosporin combined with metronidazole.
high fibre diet once inflammation settled, fibre supplements
usual operation for diverticulitis causing peritonitis?
Hartmann’s procedure: excise affected colon and create LIF end colostomy.
carried out as left colonic anastamoses have high leak rates if performed in obstructed bowel or if peritonitis.
why might elective resection be carried out for diverticulosis?
for those with chronic symptoms e.g. pain or recurrent bleeding.
sigmoid colectomy with primary anastamosis usually sufficient.
causes of stomach ischaemia?
RARE- as good anastamoses- collateral circulation?, e.g. lesser curvature supplied by both left gastric artery from celiac trunk at T12 and right gastric artery from common hepatic artery, and greater curvature- right gastroepiploic from gastroduodenal and left gastroepipoic from splenic.
causes= hiatal hernia or stomach folded in on itself
contrast DRE for pseudobstruction and sigmoid volvulus?
air on DRE with pseudobstruction
what sign may be visible on an abdominal X-ray if small bowel obstruction has been complicated by perforation?
Rigler’s sign= air on both sides of the bowel with intra-abdominal gas next to gas-filled loop of bowel, making bowel wall well defined.
when is intestinal obstruction NOT operated on?
small bowel- adhesions, and no signs of peritonitis
large bowel- volvulus, and no signs of peritonitis
investigation of intestinal obstruction?
AXR/CXR
with or without CT
3 most common causes of small bowel obstruction?
adhesions
hernias
strictures- e.g. Crohn’s
3 most common causes of large bowel obstruction?
cancer- 90% of LBOs
stricture- diverticular disease, Crohn’s-transmural inflammation
volvulus
how can a benign stricture form obstructing outflow from stomach?
fibrotic healing post peptic ulcer
location of deep inguinal ring?
mid point of inguinal ligament
indirect inguinal hernias go through DIR
hernia characteristics of cause of SBO?
tender
if so, needs operation as increased risk of perforation and ischaemia
