Constipation

Question 1

Definition

Answer 1

Difficulty emptying the bowels associated with hardened stool.
- For many patients its a chronic condition

Question 2

Primary constipation

Answer 2

As a result of disordered or ineffective regulation of colonic and anorectal neuromuscular function or brain-gut neuroenteric function. = patients have slower transit of stool through the large bowel and difficulty evacuating the faeces

Question 3

Secondary constipation

Answer 3

As a result of factors such as:
- certain medications (opiates, antipsychotics),
- metabolic disturbances (hypercalcaemia, hypothyroidism)
- neurolgical disorders - Parkinsons, spinal cord lesions
- primary diseases of the colon.
- Colonic disease: Hirschprungs, anal stricture, colorectal cancer, anal fissure
- Functional disorders: IBS, dyssynergic defecation

Question 4

Epidemiology

Answer 4

• Female
• Age > 65
• Black
• Low socioeconomic status
• DM
• Sedentary lifestyle
• Reduced dietary fibre

Question 5

Signs

Answer 5

• Abdominal mass: stool may be palpable in R/LLQ
• Anorectal lesions: haemorrhoids, fissures
• Abnormality on PR exam: hard stool, anal spasm, anal mass, anal stricutre

Question 6

Symptoms

Answer 6

• Difficulty defecation: prolonged attempts
• Infrequent stools< 3 per week
• Unsatisfactory of incomplete emptying
• Excessive straining
• Hard stools
• Overflow diarrhoea

Question 7

Diagnosis

Answer 7

Abdominal examination:
- masses
- distention
- palpable colon
PR exam:
- masses
- stool
- fissures
- haemorrhoids
- prolapse
- rectocele
Secondary investigations
- Bloods: fbc, tft, u+e, bone profile, blood glucose
- Abdo x-ray: faecal impaction, abdo masses
- Colonoscopy

Question 8

Management = Short duration constipation (<3m)

Answer 8

FIRST LINE =
- Investigate and exclude secondary cause
- Lifestyle advice: increase daily fibre intake
- Bulk forming laxatives: fybrogel (ispaghula husk), methylcellulose

Second line (hard stool, difficult to pass):
- Osmotic laxative: macrogel, lactulose

Second line (soft stool, inadequate emptying):
- Stimulant laxatives: senna, bisacodyl

Question 9

Management = Chronic constipation

Answer 9

If at least two laxatives from different classes tired at highest recommended doses for at least 6 months and failed to relieve symptoms:
- Prucalopride: prokinetic which stimulates GI motility

Faecal impaction:
- FIRST LINE = Oral macrogel +/- stimulant laxative
- Second line = suppository: bisacodyl, glycorel
- Third line = enema: sodium phosphate

Question 10

Complications

Answer 10

• Pain
• Delirium
• Anal fissure
• Haemorrhoids
• Rectocele
• Rectal ulcer syndrome
• Megarectum and megacolon: as a result of severe faecal impaction