Bowel obstruction Flashcards
3 classifications of bowel obstruction
mechanical/paralytic
open/closed
simple/strangulated
3 categories of mechanical bowel obstruction and example
luminal e.g. gall stones
within the wall e.g. stricture
outside the wall e.g. adhesion, hernia, volvulus
4 categories of paralytic ileus
sympathetic activity
local
bioechemical
pharmacological
3 causes of sympathetic activity induced colon paralysis
reflex- post op
retroperitoneal- bleed
malignant infiltration
Example of local cause of paralytic ileus
bacterial infection
2 biochemical causes of paralytic ileus
K, urea
2 pharm causes of paralytic ileus
loperamides, anticholinergics
Pathophysiology of bowel obstruction fluid loss
oedematous bowel causes the loss of fluid into the lumen, no reabsorption due to the obstruction
Motility proximal to the obstruction is
flaccid and non-functional
Motility distal to the obstruction is
normal
clinical px of mechanical obstruction
colicky pain in waves distension vomiting constipation dehydration active bowel sounds
Px of small bowel mechanical obstruction compared to lg bowel
high freq pain centrally
late distension
early vomiting
late constipation
where is the pain in a large bowel mechanical obstruction?
lower abdomen
px of a paralytic obstruction
diffuse discomfort small and large bowel distension gastric distension constipation dehydration abdominal distension non-tender no BS
Px of strangulation obstruction
persistent localised pain
locally tender
local oedema
4 questions to consider when faced with a bowel obstruction
is there an obstruction?
location- which bowel?
level?
cause?
3 main causes of bowel obstruction
adhesions, hernia, masses
diagnosis of bowel obstruction
plain radiology- AXR, erect CXR
CT to confirm diagnosis and elicit more info
3 steps to bowel obstruction management
Resuscitate- dip and suck: replace fluids, NG tube to remove fluid and air
Plan- operative or non-operative
Intervention- options available
5 indications for surgical mx of bowel obstruction
established or suspected strangulation failure of resolution post non-operative mx virgin abdomen hernia adhesive obstruction
6 aspects of non-operative care of bowel obstruction
NG suction analgesia fluid and electrolyte replacement repeated evaluation limited time period dexamethasone for metastatic lesions
5 things to consider when assessing bowel viability
colour mobile peristalsis pulse in mesentery bleeding
2 scenarios for stent use?
bridge to surgery
palliative care
What is a volvulus?
twist or abnormal rotation
Tx for volvulus
flexible sigmoidoscopy to decompress
define shock
a pathological condition that can suddenly affect the haemodynamic equilibrium, usually manifested by the failure to perfuse or oxygenate vital organs.
3 main categories of shock
hypovolemic
cardiogenic
distributive
5 investigation for PR bleeding causing shock
gastroscopy CT angiogram mesenteric angiogram colonoscopy surgery
4 benefits of colonoscopy compared to angiography
widely available
cheap
less invasive
biopsy can be taken
3 benefits of angiography compared to colonscopy
can detect small bowel lesions
unprepared colon
detection of angiodysplasia
5 causes of lower GI bleeding
diverticular disease haemorrhoids ischaemic colitis rectal ulcer ulcerative colitis
5 causes of haematemesis
peptic ulcer gastroduodenal ulcer oesophagitis varices Mallor Weiss tear
3 Ix for haematemesis
bloods
AXR, CXR, erect CXR
endoscopy
Tx for oesophageal varices
banding
Tx for Mallory Weiss tear
adrenaline injection
Tx for ulcers
adrenaline injection and mechanical clips
4 aspects to ulcer follow up
PPI
H. pylori eradication
stop NSAIDs
repeat endoscopy
How do oesophageal varices develop?
if there is liver disease then there is backflow of blood from the portal circulation down the path of least resistance. This means that there is redistribution of blood into the oesophageal vessels causing dilations.
3 tx for oesophageal varices
monitoring
anti hypertensives e.g propanolol
banding
Tx of perianal abscess
incision and drainage
2 symptoms of perianal abscess
erythematous, painful to touch
what is a fistula?
abnormal connection between 2 epithelial surfaces
complication of fistula
repeated infections
3 tx of fistula
cut it open to prevent repeated infection
fistula glue
fistula plug
LIFT procedure to dissect it out
what is a perianal haematoma ?
thrombosed external haemorrhoid
tx for perianal haematoma?
analgesic, laxative, ice packs, compression
risk factors for haemorrhoids
constipation, straining, poor bowel habits, sitting on the toilet for too long
tx for haemorrhoids
banding, excision
where do anal fissures occur?
anterior and posteriorly
what is an anal fissure?
tearing of the perianal skin
2 causes of anal fissure
trauma
hard stool
2 symptoms of anal fissure
painful, glass like tearing
Mx of anal fissure
laxative, anaglesia, cream to relax the muscle, surgery
Which HPV virus causes low grade anal warts?
6 and 11
Which HPV virus causes high grade anal warts?
16, 18, 31, 33
anal warts can lead to what
anal cancer
tx of anal warts
excision, cryotreatment, topical
2 risk factors for anal cancer
HIV+
anal sex
what type of surgery is used to excise anal cancer?
ELAPE
Tx for rectal prolapse
reduce, ice packs, gel, laxatives, surgery
