Obstruction Flashcards
How does SBO present?
Colicky pain
N+V
Constipation w complete obstruction, may not be absolute w higher obstruction
Distension
What are the causes of SBO in adults?
Adhesions - prev surgery Hernias Crohns Malignancy Appendicitis
What are the causes of LBO?
colon ca
constipation
diverticular stricture
volvulus - sigmoid or caecal
how does presentation of SBO differ to LBO
SBO: - Vomiting occurs early - less distension - pain higher in abdo LBO: - pain more constant
How does AXR differ in SBO and LBO?
SBO: valvulae conniventes extend all the way across
LBO: haustra that do NOT cross width
What are the upper limit of normal diameter of the small bowel, colon and caecum?
3
6
9 cm
369 rule
What is paralytic ileus?How does it present?
acute functional small bowel obstruction from reduced motility - no pain and bowel sounds are absent
What is simple obstructed bowel?
one obstructing point and no vascular compromise
What is closed loop obstruction? Give examples
Obstruction at two points forming a loop of grossly extended bowel at risk of perforation
e.g. sigmoid volvulus, distension w competent ileocaecal valve
How does strangulation present?
- Pt more ill than u would expect
- Sharper more constant and localised pain
- Peritonism (cardinal sign)
- Fever and raised WCC
What type of obstruction can usually be managed conservatively?
incomplete small bowel obstruction (hernia or adhesions)
what obstructions require emergency surgery?
strangulation
closed loop obstruction
What is the immediate management of bowel obstruction?
drip and suck
NBM and IV fluids
Nasogastric tube for SBO or vomiting to minimise risk of aspiration
Pain relief
What investigations would u carry out
blood: fbc, amylase, u+e
AXR
erect CXR
When is a CT indicated?
if clinical and radiographic findings are inconclusive
What can lead to paralytic ileus?
abdo surgery
pancreatitis or any localised peritonitis
spinal surgery
What is pseudo-obstruction? what is acute colonic pseudo-obstruction also known as?
What can be used to treat it?
like mechanical GI obstruction but no cause for obstruction found
acute colonic pseudo obstruction - Ogilvie’s syndrome
treatment - neostigmine or colonoscopic decompression
What is sigmoid volvulus?
Bowel twists on its mesentery ->severe rapid strangulated obstruction
In who does sigmoid volvulus tend to occur?
Elderly constipated and comorbid pt
How is sigmoid volvulus managed?
Sigmoidoscopy and insertion of flatus tube
Sigmoid colectomy may be required
What is the characteristic sign seen on AXR w sigmoid volvulus?
coffee bean sign
What can sigmoid volvulus lead to if left untreated?
perforation and fatal peritonitis
What are causes of SBO in children?
appendicitis
intussusception
Intestinal atresia
Volvulus
What are the symptoms of SBO?
- Pain - intermittent and crampy, severe
- Failure to pass flatus or stool
- Vomiting - after pain, bilious?
- Distension
- Tenderness - ischaemia
- Mass - if malignancy
- Peritonitis - if perforation or ischaemia/necrosis
What are the cardinal features of intestinal obstruction?
- Vomiting
- Colic - occurs early
- Constipation - may be absolute in distal, less pronounced if obstruction is high
- Abdo distension - ↑ as the obstruction progresses with active, ‘tinkling’ bowel sounds
what is ileus?
functional obstruction due to reduced bowel motility
What are the features of ileus
absent bowel sounds
less pain
What is the immediate action of bowel obstruction?
DRIP AND SUCK - NGT + IVI Analgesia Bloods - amylase, FBC, U&E Catheter for fluid status AXR, erect CXR (pneumoperitoneum)
What further imaging would u do in bowel obstruction?
CT - oral gastrografin helps identify obstruction and help ease it
Consider colonoscopy but beware perforation
What surgical options are there for bowel obstruction? what cases is surgery indicated?
Strangulation - emergency surgery
Closed loop - surgery or endoscopic decompression
Malignancy - endoscopic palliation
What cause of obstruction rarely leads to surgery ?
SBO due to adhesions
