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Flashcards in Constipation Deck (30)
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1
Q

What is the general definition of constipation?

A

Passage of =2 bowel movements/week, with a sense of straining, pain or incomplete evacuation

2
Q

What might constipation + rectal bleeding indicate?

A

Cancer

3
Q

What might constipation + distention + active bowel sounds indicate?

A

Stricture/obstruction

4
Q

What might constipation + menorrhagia indicate?

A

Hypothyroidism

5
Q

What would you consider asking someone who was presenting with constipation?

A
  • Frequency/nature/constistency?
  • Recent change?
  • Blood/mucus?
  • Diarrhoea as well as constipation?
  • Digitating rectum/vagina to pass stool?
  • Diet
  • Drugs
6
Q

What is essential to do when examining someone with constipation?

A

PR exam

7
Q

What anorectal disease can cause constipation?

A
  • Anal/colorectal cancer
  • Fissures
  • Rectal prolapse
  • Proctalgia fugax
  • Mucosal ulceration
  • Pelvic muscle/levator ani dysfunction
8
Q

What are causes of intestinal obstruction which can cause constipation?

A
  • Colorectal cancer
  • Strictures
  • Pelvic mass
  • Diverticulosis
  • Pseudo-obstruction
9
Q

What are metabolic/endocrine causes of constipation?

A
  • Hypercalcaemia
  • Hypothyroidism
  • Hypokalaemia
  • Porphyria
  • Lead poisoning
10
Q

What drugs can cause constipation?

A
  • Opiates
  • Anticholinergics
  • Iron
  • Antacids
  • Diuretics
  • CCBs
11
Q

What neuromuscular problems can cause constipation?

A
  • Spinal/nerve injury
  • Systemic sclerosis
  • Diabetic neuropathy
  • Hirschsprung’s disease
  • Chagas disease
12
Q

What are general causes of constipation?

A
  • Poor diet +/- lack of exercise
  • Dehydration
  • IBS
  • Old age
  • Post-operative pain
13
Q

What investigations might you perform in someone with constipation?

A

None in those who are young - consider investigating if red flag symptoms:

  • Bloods - FBC, ESR, U+E’s, Ca2+, TFTs
  • Other - Colonoscopy + biopsy
14
Q

What lifestyle advice would you give someone with constipation?

A

Reassurance

  • Drink more
  • Exercise more
  • High-fibre diet
15
Q

What medications can be used to aid constipation?

A
  • Bulking agents
  • Stimulant laxatives
  • Stool softeners
  • Osmotic laxatives
16
Q

What are bulking agents?

A

Bulk forming laxatives consist of indigestible polysaccharides which increase faecal mass. This in turn stimulates the stretch receptors in the bowel mucosa which increases peristalsis and defaecation.

17
Q

What conditions are bulk forming laxatives most useful in?

A
  • IBS
  • Diverticulitis
  • Those with colostomies/ileostomies
18
Q

What are examples of bulk forming agents?

A
  • Dietary fibre
  • Wheat bran
  • Methylcellulose
  • Mucilaginous gums – sterculia
  • Mucilaginous seeds and seed coats, e.g. ispaghula husk
  • Normacol
19
Q

How do stool softeners work?

A

Soften the stools making them easier to pass. Arachis oil is a mixture of peanut and ground-nut oil. It is given as an enema in patients with faecal impaction. It works in two ways. It softens the stool and acts as a lubricant.

20
Q

What conditions are stool softeners most commonly used in?

A

Managing painful anal conditions e.g. fissures, haemorrhoids

21
Q

What are examples of osmotic laxatives?

A
  • KleanPrep
  • Movicol
  • Sodium Picosulphate (Picolax)
  • Lactulose
  • Phosphate enema
22
Q

How do osmotic laxatives work?

A

Increase the amount of water in the large bowel, either by drawing fluid from the body into the bowel or by retaining the fluid they were administered with due to osmotic gradient created by the drug

23
Q

Why is lactulose useful in hepatic encephalopathy?

A

Produces low faecal pH, that discourages ammonium producing bacteria from growing

24
Q

When are phosphate enemas used?

A

Rapid bowel evacuation prior to procedures

25
Q

How do stimulant laxatives work?

A

Increase intestinal motility - speculated that they both act as osmotic laxative and stimulate myenteric plexus

26
Q

When would you not use stimulant laxatives in someone with contipation?

A

If it was caused by intestinal obstruction or acute colitis

27
Q

What can occur if you use stimulant laxatives for prolonged periods?

A

Colonic atony

28
Q

What are examples of stimulant laxatives?

A
  • Phenolphthalein
  • Bisacodyl
  • Anthraquinones – senna and dantron (only for the terminally ill)
  • Docusate sodium
  • Methylnaltrexone (for opioid induced constipation)
  • Lubiprostone
  • Prucalopride
  • Linaclotide
  • Sodium picosulfate
29
Q

How would you manage constipation?

A
  • Lifestyle advice
  • Consider medications/evacuation measures
  • Treat cause
30
Q

What enemas are used in those with constipation?

A
  • Arachis oil
  • Docusate sodium
  • Hypertonic phosphate
  • Sodium citrate