Constipation

Question 1

What should you ask the patient?

Answer 1

Freq, nature and consistency?

Blood/mucus in stools

Change in bowel habit - Cancer

Diet and drugs

Question 2

What does alternating with D suggest?

Define C

Answer 2

IBS

<2 bowel motions per wk

Question 3

Causes - bowel disease

Anally - 2

What can happen to the rectum making it hard for stool to pass?

A disease more commonly presenting with D

What might happen in Crohn’s that stops stool from passing?

Obvious cause?

Extraluminal cause - 1

Answer 3

Anal fissure
Anal stricture

Rectal prolapse

Colorectal cancer though D is a more common presentation

Crohns stricture

Bowel obstruction

Compressive pelvis mass - fetus, fibroids

Question 4

Causes - dietary - 2

Causes - functional - 1

Answer 4

Dehydration
Low fibre diet

IBS

Question 5

Causes - metabolic:

Calcium imbalance - Hyper or hypo
Potassium imbalance - Hyper or hypo

What type of thyroid disease will cause C?

Answer 5

Hypercalcaemia
Hypokalaemia

Hypothyroidism

Question 6

Causes - neurological - 2

Causes - psychiatric - 1

Answer 6

Spinal cord lesion
Parkinsons

Depression

Question 7

Causes - drugs -

Answer 7

Opiates 
Iron 
TCA
Diuretics 
CCB's

Question 8

Investigations:

Basic approach - what should be done first?
When is further investigation needed? - 2

Answer 8

PR exam

New-onset over 40 years old or signs of colorectal carcinoma

Question 9

Investigations:

Bloods:

• Why do you do FBC?
• Test for inflammation
• Test for metabolic cause
• Test for thyroid disease
• What test should be done in men?

Answer 9

Checking ferritin and Total Iron Binding Capacity (TIBC) for microcytic anaemia

ESR/CRP

U&E’S - Potassium and calcium

TFT

PSA - (Prostate-specific antigen) - Constipation increases the levels of serum PSA in men

Question 10

Management:

Diet

What habit should be encouraged?

If you have treated underlying cause and it has still not resolved, what should be done?

Answer 10

Increase fibre and fluid intake

Encourage regular bowel movements

Laxatives

Question 11

Laxatives:

Name the 4 types

Answer 11

Bulking agents
Stimulant laxatives
Osmotic laxatives
Stool softn

Question 12

Laxatives - Bulking agents:

What is it?

MOA

What do you take it with?

When does it begin to work?

Complications - 3

Answer 12

Bulking agents include soluble fibre (i.e. psyllium, ispaghula) and insoluble fibre (i.e. wheat bran), which, when taken with water, increase stool bulk and stool frequency.

Increases faecal mass
Easing intestinal transit

Plenty of fluids

Few days

Dysphagia
Obstruction
Impaction

Question 13

Laxatives - Stimulant laxatives

Name a few examples - 3

MOA - 2

SE - 2

Contraindication - 1

Answer 13

Senna
Docusate (also a softener)
Glycerol

‘Alter water and electrolyte’ secretion and GI motility

Abdominal cramps
GI irritation

Obstruction

Question 14

Laxatives - osmotic laxatives

MOA

Lactulose - in what situation does it tend to be used and why? - 1 side effect?

Macrogol (polyethylene glycol) - in what situation does it tend to be used? 2 side effects?

Magnesium sulfate - why is it used often? 2 side effects?

Answer 14

Poorly absorbed
Osmotically active substances
Leading to fluid retention in bowel = SOFT STOOL

Hepatic encephalopathy due to anti-ammonia effects
Bloating

Impaction
Bloating and nausea

Rapid onset
Watery stool and urgency

Question 15

3 examples of stool softeners?

In what situation does it tend to be used and why?

Answer 15

Docusate
Arachis oil (enema)
Liquid paraffin

Anal fissures or any painful anal pathology - easier passage

Question 16

General causes of constipation:

Lifestyle - 2

Diagnosis of exclusion

Care home

What may happen after an operation? - 2

Why might a hospital environment cause C? - 2

Answer 16

Poor diet +/- lack of exercise

Poor fluid intake

IBS

Old age

Post-operative pain - pain meds and muscle relaxants

Hospital environment - reduced privacy, having to use a bedpan