Constipation

Question 1

What are the diagnostic features of constipation?

Answer 1

all of the following features occur for more than one fourth of defections
- must meet at least two of the following criteria

straining (key feature)
lumpy or hard stools
sense of incomplete evacuation
sense of anorectal obstruction/blockage
manual manoeuvres to facilitate defacations
- support of pelvic floor
fewer than 3 spontaneous bowel movements per week

Question 2

What are contributing factors to constipation?

Answer 2

lack of fibre (wholemeal bread, potatoes, vegetables)
low fluid intake (2L should be the normal)
sedentary lifestyle ( little to no physical activity is done)
pregnancy – gut bacteria
undiagnosed conditions (Parkinson’s or hypothyroidism)

medications

• opioids = codeine, morphine, diamorphine
• anti-epileptics
• calcium and iron supplements

Question 3

What is constipation?

Answer 3

chronic constipation is a polysymptomatic heterogeneous disorder

patients define constipation on the basis of

• excessive straining
• a sense of incomplete evacuation, failed or lengthy attempts to defecate
• hard stools
• less frequently, by the number of stools per week

Question 4

What are differential diagnosis to constipation?

Answer 4

intestinal obstruction (faecal impaction)
- when a large, hard mass of poop gets stuck in the digestive tract and can't get pushed out the usual way

Question 5

What are complications that can occur with constipation?

Answer 5

intestinal obstruction (faecal impaction)
anal fissure
- tear or open sore (ulcer) that develops in the lining of the large intestine, near the anus
faecal and urinary incontinence
- problem holding in urine or stool
rectal bleeding
haemorrhoids (piles)
- swellings containing enlarged blood vessels that are found inside or around the bottom (the rectum and anus).

Question 6

What are the symptoms of constipation?

Answer 6

abdominal discomfort
cramps 
bloating
feeling of incomplete defecation 
discomfort when passing stool
requiring manual assistance

Question 7

When should constipation be referred?

Answer 7

unexplained weight loss
- possibly cancer = colon cancer
large amounts of blood in stool
- could be inflammatory bowel disease, ulcerative colitis, crohn's disease
constipation with nausea and vomiting
- possibly cancer 
impacted
suspected laxative abuse
- eating disorder

if over 14 days

Question 8

What are the questions you need to ask when speaking with patients?

Answer 8

who
- elderly and children need referral

what are the symptoms
- cramps, pain upon passing stool, bleeding

how long
- should be referred if over 14 days

what actions have been taken already
- any medications

what other medications do you take
- antidepressant, anti-epileptics

Question 9

What are symptoms of bowel cancer?

Answer 9

can be subtle and do not necessarily make you feel ill

persistent change in bowel habit
blood in the poo without any other symptoms (haemorrhoids)
abdominal pain/bloating/discomfort always brought on by eating

Question 10

What are the effects of laxative abuse? What does laxative dependence?

Answer 10

effects

• dehydration, electrolyte imbalances, mineral deficiencies
• long term or permanent damage to digestive system
• chronic constipation
• damage to the nerves and muscles of the colon

laxative dependence

• increased dose required
• degeneration of myenteric plexus of colon
• hypokalaemia (arrhythmia)
• hypomagnesia (stroke risk)

Question 11

What are lifestyles measures you can take for constipation?

Answer 11

increase fluid intake
- 2 litres daily

increase fibre intake
- fruits, vegetables, wholemeal breads
= attracts water into the stool making it softer and easier to pass with less strain

exercise

review medicines
- antidepressants, anti-epileptics

Question 12

What is the mechanism of action of bulk forming laxatives and osmotic laxatives? What is their side effects? What are examples?

Answer 12

bulk forming laxatives
- retains water in the gut, increases faecal bulk and stimulates peristalsis
- onset of action is 12-24 hours (delayed onset)
- side effects = bloating, distension, flatulence
= fybogel (ispaghula husk), methylcellulose

osmotic laxatives
- increases water absorption in the gut, increases faecal bulk and stimulates peristalsis
- onset of action is 4-48 hours
= lactulose, macrogol

Question 13

What is the mechanism of action of stool softeners and stimulative laxatives? What is their side effects? What are examples?

Answer 13

stool softeners
- reduces surface tension, increases penetration of intestinal fluids into faeces and stimulates peristalsis
= decussate

stimulative laxatives
- stimulates colonic nerves, increases intestinal motility and stimulates peristalsis
- onset of action is 8-12 hours
- side effects = abdominal cramps, diarrhoea
= senokot (senna), dulcolax (bisacodyl)

Question 14

What are the new types of laxatives?

Answer 14

prucalopride
- selective serotonin 5HT4 agonist with prokinetic properties
= strengthen the lower esophageal sphincter (LES) and cause the contents of the stomach to empty faster (promote intestinal motility)

for women only

Question 15

How doe constipation present in children? When should they be referred? What are the treatments?

Answer 15

symptoms

• tummy ache
• pain when passing stool
• gets upset or anxious about going to the toilet

referral

• feels dizzy or weak
• marked anal pain on defecation or blood in stools

treatment

• increase fluids and fibres (prune/pear/apple juice can act as stool softeners)
• increases activity
• use osmotic/stimulative laxatives or stool softeners

Question 16

What are the preferred choice of laxatives for pregnant women? What should be avoided?

Answer 16

preferred

• bulk forming laxatives
• osmotic laxatives

avoid
- stimulative laxatives in the 3rd trimester
= Senna can enter breast milk and cause colic and diarrhoea in the infant