irritable bowel syndrome & bowel ischaemia Flashcards
what is irritable bowel syndrome
’ functional bowel disorder’
mixed group of abdo symptoms with no organic cause
epidemiology of IBS
Age of onset under 40yrs
more common in femalles
1 in 5 in the western world
risk factors for IBS
Previous gastroenteritis
Previous severe long-term diarrhoea
Anxiety and depression
Psychological stress, trauma, abuse
What are the three types of IBS
IBS-C – with constipation
IBS-D – with diarrhoea
IBS-M – mixed, with alternating constipation & diarrhoea
clinical presentation of IBS
Abdo pain
Bloating
Change in bowel habit
diagnosable criteria of irritable bowel syndrome
Abdominal pain/discomfort associated with 2+ of:
Relieved by defecation
Altered stool form
Altered bowel frequency
what other symptoms may a patient complain of
Urgency
Incomplete evacuation
Abdo bloating/distension
Mucus in rectum & stool
Worsening of symptoms after food
Abdo tenderness
symptoms are exacerbated by
stress
menstruation
gastroenteritis
food
red flag symptoms for colon cancer
- Unexplained weight loss
- Bleeding on defecation/wiping
- Abdo/rectal mass
- Raised inflammatory markers
- Anaemia
- Aged over 50
what investigations would you do for ibs
blood test
faecal calprotectin
colonoscopy
management for mild IBS
-Education and reassurance
- dietary modification
- keep a food diary - to identify triggers
management for IBS-C
- stool softeners
-oral laxatives - avoid alcohol
management for IBS-D
AVOID insoluble fiber
Makes diarrhoea
Cereals, whole-wheat bread, lentils, apples, avocados
medication for bloating
antispasmodics
buscopan
medication for diarrhoea
loperamide
medication for constipation
laxatives- macrogol
What is the mesentery
Mesenteries are double layers of peritoneum in the abdominal cavity and are continuations of the visceral and parietal peritoneum
What is chronic mesenteric ischaemia
narrowing of GI blood vessels causing decreased supply to bowel. same as angina in heart
Risk factors for chronic mesenteric ischaemia
same as cardiac
classic triad of signs and symptoms of chronic mesenteric ischaemia
- central colicky abdominal pain after food
- weight loss
- abdominal bruit
investigations for CMI
CT contrast angiography
Define acute mesenteric ischaemia
blockage of mesenteric arteries/ veins – leading to small bowel ischaemia
Affects superior mesenteric artery
Mesenteric ischaemia epidemiology
Age: >40
F>M
Aetiology of mesenteric ischaemia
Arterial - thrombosis, embolism
Venous - Thrombosis
Non- occlusive - Hypoperfusion
RFs for mesenteric ischaemia
Age
AF
Atherosclerosis
MI
Vasculitis
IE
Physiology of SI blood circulation
- SI need high oxygen for digestion > susceptible to tissue injury from ischaemia
- Reduce risk: mesenteric arteries branch and reconnect at points froming collateral circulation - blood flow reduced one way blood received from another pathway
S + S of mesenteric ischaemia
Rectal bleeding
DIARRHOEA
N/V
Fever
Weight loss
Small Bowel infarction (mesenteric ischaemia)
- SBI - decrease in BF to SI
- ISchaemic injury leads to production of ROS > damage DNA,RNA and protein in cell leading to cell death
- BF returns to tissue called reperfusion causes reperfusion injury
- ROS triggers inflammatory response - neutrophils remove dead cells + release cytokines TNFa
- Blood vessels become more permeable to fluid + immune cells > bowel oedema
examples of mesenteric vessels
superior + inferior mesenteric artery
SMV
IMV
right and middle colic artery
What does acute mesenteric ischaemia cause
Bowel infarction + perforation
Short bowel syndrome
Strictures
Most commonly affected vessel
SMA
Causes of acute mesenteric ischaemia
- embolus
- low perfusion
- thrombus
classic triad of signs and symptoms for acute mesenteric ischaemia
-severe colicky abdominal pain
- abdominal bruit
- rapid hypovolaemia
How does chronic mesenteric ischaemia present
- abdo pain after eating
- fear of eating
- weight loss
investigations for AMI
- History and diagnosis
1st line- CT contrast/ angiography
GOLD- colonoscopy
treatment for ami
Supportive
- IV fluids
- Catheter
- o2
- analgesia
What is ischaemic colitis
Bowel ischaemia which affects the large bowel. This is mainly due to pathology in the inferior mesenteric artery territory and can range from mild ischaemia to gangrenous colitis.
Causes of ischaemic colitis (intestinal ischaemia when intestines small and large dont get sufficient blood)
Non occlusive: HF, Renal impairment, Cocaine use
Arterial: Thrombus, embolism
Venous: Embolism
RFs for Ischaemic colitis
Older age
Peripheral vascular disease
AF
Atherosclerosis
MI
Cocaine
what is the most common ischaemic bowel disease
ischaemic collitis
S+ S of IC
Abdom tenderness
Pyrexia
Tachycardia
Diarrhoea
Fever
Haematochezia
what is most commonly affected in ischamic collitis
splenic flexure despite dual blood supply of sma and ima
Investigations for IC
FBC, U&Es, VBG
GI endoscopy - GS
CT
signs and symptoms of ischaemic colitis
- severe colicky abdominal pain
- abdominal bruit
- rapid hypovolaemia
Management of IC
NBM
IV Fluid
Broad spectrum ANTIBIOTICS
