Faecal Loading

Faecal loading is the accumulation of a large volume of hard or soft stool in the rectum and colon that the patient cannot evacuate, ranging from retention to complete impaction.

• It is common in older adults, institutionalised patients, children with functional constipation, and patients with neurological disease, immobility, dementia, spinal cord injury or opioid use.
• Causes: low fibre and fluid intake, immobility, opioids, anticholinergics, calcium channel blockers, iron, antacids, hypothyroidism, hypercalcaemia, hypokalaemia, Parkinson disease, diabetic neuropathy and pelvic floor disorders.
• Impaction means a hard immovable mass; overflow diarrhoea occurs around it.

Infrequent, hard stools, straining, lower abdominal pain, bloating, anorexia, nausea.

• Overflow incontinence: liquid, often offensive leakage with soiling; urinary retention or frequency.
• Delirium or agitation in the elderly; abdominal fullness with a palpable faecal mass in the left iliac fossa; rectal examination shows a loaded rectum (or an empty rectum with proximal loading on imaging).
• Differential diagnosis: colorectal cancer, bowel obstruction, volvulus, Hirschsprung disease (children), infective or inflammatory diarrhoea, irritable bowel syndrome, ovarian mass.
• Complications: stercoral ulceration, rectal bleeding, perforation, bowel obstruction, urinary retention and hydronephrosis, haemorrhoids, fissure, rectal prolapse, sacral pressure ulcers, and faecal incontinence.

Clinical, with abdominal and digital rectal examination.

• Plain abdominal radiograph to show faecal loading, exclude obstruction; CT for suspected perforation or tumour.
• Bloods: calcium, potassium, thyroid function, glucose, urea and creatinine.
• Colonoscopy (after clearance) for alarm features: age above 50 years, rectal bleeding, weight loss, anaemia.

Supportive: fluids (1.5 to 2 L daily unless restricted), fibre 25 to 30 g daily, physical activity, toilet routine 20 to 30 minutes after meals with feet raised on a stool, review constipating drugs, privacy and assistance with toileting.

Pharmacological

• Disimpaction in adults: macrogol (polyethylene glycol with electrolytes) 8 sachets dissolved in 1 L water drunk over 6 hours, daily for up to 3 days; or bisacodyl 10 mg suppository daily with glycerol 4 g suppositories; or sodium citrate micro-enema 5 mL; or arachis oil enema 130 mL retained overnight for hard stool, followed the next morning by a glycerol or bisacodyl suppository.
• Avoid sodium phosphate enemas in renal impairment, children under 2 years and frail older adults.
• Children (1 to 12 years): macrogol 3350 1 to 1.5 g/kg daily for 3 days (maximum 100 g daily), then 0.4 to 0.8 g/kg daily maintenance.
• Maintenance: macrogol 1 to 3 sachets daily, or lactulose 15 to 30 mL twice daily, plus senna 15 mg at night or bisacodyl 5 to 10 mg at night; continue for several months.
• Opioid induced: add methylnaltrexone 12 mg SC on alternate days or naloxegol 25 mg daily.

Procedures: manual disimpaction under sedation or anaesthesia when enemas fail; surgery for perforation or ischaemia.

Special groups: neurological patients (scheduled bowel programme with suppositories and digital stimulation), children (behavioural programme and toilet training), palliative care (prophylactic laxatives with every opioid).

Red flags: abdominal distension with vomiting, peritonism, rectal bleeding, fever, new neurological signs (cauda equina), failure of disimpaction.

Follow-up: review at 1 to 2 weeks, ensure daily soft stool; taper laxatives slowly only after 1 to 3 months of normal bowel habit.