This information is sourced from Health Improvement Scotland and PANG:
Bowel obstruction in advanced illness is common, especially in cases of gynaecological or bowel cancer and can present over several days. Bowel obstruction may be due to:
- a mechanical blockage of the lumen e.g. from tumour or even from severe constipation
- external bowel compression eg from peritoneal disease or ascites
- peristaltic failure ( e.g. due to drugs such as opioids or anticholinergic drugs such as Cyclizine which slow the bowel, or tumour invading nerve plexus
Clinical features
Symptoms vary according to the level of the blockage in the GI tract, and whether partial or complete
Key symptoms of bowel obstruction include:
- intermittent nausea (often relieved by vomiting) - often large volume if the level of obstruction is small bowel or higher. May contain undigested food/tablets
- abdominal pain (may be colicky) especially in complete obstruction
- abdominal distention (particularly if large bowel obstruction)
- constipation and often appetite loss
Late signs include:
- worsening nausea and/or faeculent vomiting as obstruction progresses
An initial approach to treatment (many episodes of subacute obstruction are reversible)
- Review the route of medication as oral medicines may no longer be absorbed. A syrynge pump may be the best option to deliver a combination of drugs
- Treatment depends on level, cause, performance status and patient goals
- Treat constipation with stimulant laxatives (but reduce if colic worsens)
- Stop or reduce drugs that maybe reducing peristalsis, and give a trial of prokinetics eg Metoclopramide 30mg-40mg in a syringe pump
- A trial of steroids (eg Dexamethasone 6mg-8mg subcutameously) may reduce the impact of external compression
- Remember the severe social impact that this syndrome can have - eating is at the heart of normal family life. Bowel obstruction and its associated symptoms can cause distress and demoralisation
- A low residue (low fibre) diet can help prevent bowel obstruction, or support recovery from a blockage - see download on the right
- Mouth care is really important
An approach to managing terminal bowel obstruction at home (or in hospital)
If due to complete mechanical obstruction at any level of the bowel:
- Treat nausea with Cyclizine, up to 100 mg/24 hours via pump
- If nausea persists, add Haloperidol, 2.5–5 mg/24 hours in a pump or as a single night-time dose if no pump is available
- Levomepromazine is another option; 5–12.5 mg/24 hours in a pump or as a single night-time dose - can be very sedative even in low doses
- Avoid prokinetics as these will cause colic in complete obstruction, and will increase the risk of perforation
- A trial of Dexamethasone subcutaneously may already be in place - need to stop/reduce this if no response after 5 days as will be making patient hungry when eating is difficult
- It is useful to have Hyoscine butylbromide (Buscopan) available in case of severe colic 60–120 mg/24 hours via pump or 20 mg immediately by subcutaneous injection
- An NG tube may be really helpful if the patient can tolerate this, and will reduce the need for antiemetics
- If large-volume vomiting persists (and an NG is not possible) then do contact your specialist palliative care team
Remember to treat the background abdominal pain - usually responds well to an opioid
Patients who are in complete bowel obstruction, with no surgical or stenting options, will have a short prognosis
Specialist care
Imaging with CT to detect level of obstruction
Treatment options may include surgery/stoma formation or stenting if performance status good enough