How to assess and manage constipation?

Comprehensive Assessment of Constipation

A thorough assessment of constipation requires both a detailed medical history and physical examination, with digital rectal examination being essential for proper evaluation. 1

Medical History Components

The medical history should elicit key facts when constipation is suspected:

• Date of last defecation and frequency of bowel movements 1
• Consistency of the stool and recent changes in bowel patterns 1
• Presence or absence of urge to defecate 1
• Sensation of evacuation (complete or incomplete) 1
• Presence or absence of faecal incontinence, including rectal leakage 1
• Evidence of blood or mucus on defecation 1
• Current and previous laxative use 1
• Need for digital manipulation to assist or manage evacuation 1

Risk Factor Assessment

Assessment should include questions to determine possible causes for constipation:

• Eating and drinking habits, particularly fiber and fluid intake 1
• Medication use (both prescribed and over-the-counter), with special attention to opioids which cause constipation without developing tolerance 1, 2
• Level of physical activity relative to stage of illness 1
• Pre-existing irritable bowel syndrome or diverticular disease 1
• Other comorbid diseases (e.g., heart failure, chronic pulmonary airway disease) 1
• Environmental factors (e.g., lack of privacy, need for assistance, bed-bound status) 1, 2
• Age (elderly individuals are five times more prone to constipation) 1, 2

Physical Examination

Physical assessment should include:

Abdominal Examination (including auscultation)

• Distension 1
• Abdominal masses 1
• Liver enlargement 1
• Tenderness 1
• Increased/decreased bowel sounds 1

Perineal Inspection

• Skin tags 1
• Fissures 1
• Prolapse 1
• Anal warts 1
• Perianal ulceration 1
• Complete absence of stool 1
• Blood 1

Digital Rectal Examination (DRE)

• Inner hemorrhoids 1
• Sphincter tone 1
• Tenderness 1
• Obstruction/stenosis 1
• Impacted feces 1
• Tumor masses 1

Special Considerations

• If constipation is considered part of a spinal cord compression syndrome, full neurological examination is essential, including assessment of anal sphincter tone and rectal sensation 1
• In elderly patients, particular attention should be paid to medication review and living situation 1, 2

Diagnostic Testing

• Investigations are not routinely necessary for all patients with constipation 1, 3

• If clinically suspected, check corrected calcium levels and thyroid function 1

• More extensive investigation is warranted for those with:

  • Severe symptoms 1
  • Sudden changes in number and consistency of bowel movements 1
  • Blood in the stool 1
  • Age over 50 years (alarm sign) 3, 4
  • Weight loss 3, 4
  • Anemia 3, 4
  • Family history positive for colorectal cancer 3, 4

• Patient-reported outcome measures (PROMs) are a preferred aspect of clinical assessment of constipation 1

• The Bowel Function Index (BFI) is recommended as a validated tool for assessing constipation, particularly opioid-induced constipation 1

Common Pitfalls to Avoid

• Relying solely on stool frequency for diagnosis without considering other symptoms like straining, incomplete evacuation, and sense of anorectal blockage 5, 6
• Failing to perform digital rectal examination, which is essential for proper assessment 1
• Not distinguishing between different subtypes of constipation (slow transit vs. defecatory disorders) 7, 4
• Overlooking medication-induced constipation, particularly from opioids 2, 5
• Neglecting to rule out organic causes before diagnosing functional constipation 7, 3

By following this comprehensive assessment approach, clinicians can effectively evaluate constipation and determine the appropriate management strategy based on the underlying cause.