obstruction occurs in about 3% of patients with advanced
cancer, most commonly with cancers of the ovary (25%) and colo-rectal cancer (10%), but occasionally with endometrial,
prostate, bladder and stomach cancers, and lymphomas.
patients who develop intestinal obstruction it is often
assumed that recurrent tumor is responsible. However,
severe constipation can mimic obstruction.
Assessment – Symptoms can include:
causes episodic severe pain (i.e., the severity of the pain
fluctuates) and it can be associated with bubbling bowel
noises (borborygmi) and also nausea. It does not respond to
opioids, but responds to an anti-spasmodic such as
can occur as well as constipation – intestinal dysfunction
is often a more correct term than “obstruction”, because the
obstruction can be intermittent and bowel function can
return spontaneously after a few days.
distinction between nausea (a very unpleasant symptom,
albeit invisible) and vomiting (which the patient may
not find too distressing if it is intermittent).
distention. Is it gaseous, or is it in fact ascites which
could be relieved by paracentesis? Large tumor masses preclude
surgery. Lack of distention suggests extensive fixation of
bowel by tumor deposits and means surgery is unlikely to help.
Perform a rectal examination to exclude constipation.
abdominal x-rays may show fluid levels. Barium studies are
useful and can usually delineate a large bowel obstruction.
and rehydration (“conservative management”)
Continuous subcutaneous infusion of drugs (“symptomatic
1. It is
important to consider surgery in a cancer patient who
develops obstruction for the first time, because:
selected patients can get useful palliation for several
months. On the other hand, operative morality is high (14% to
obstruction recurs, medical management focusing on symptom
control is usually a better option for the patient than
conservative management, naso-gastric suction and IV
rehydration are important if surgery is planned, but they
should not be used to control symptoms, since they are rarely
effective and only add to the discomfort of terminally ill
patients. They usually involve hospitalization, immobility and
discomfort and should be avoided. In terms of symptom
control, most studies show a poor response rate (1 % to 14%)
for conservative management.
Symptomatic management with drugs (usually via continuous
subcutaneous infusion using a small, portable battery-operated pump) can effectively control symptoms and has
In a study
of 40 hospice patients with intestinal obstruction treated
medically it was possible to abolish symptoms in the majority
of cases. (Only 30% of patients continued to have mild
symptoms of visceral pain, colic or nausea. 76% of patients
continued to have mild vomiting - not more than one episode
per day with little or no nausea.)
Controlling symptoms – A continuous subcutaneous
infusion using a small, portable battery-operated pump is
usually the best route for drug administration, although mild
or intermittent pain can be controlled using other routes
(sublingual, rectal, IM injection).
The drugs commonly used (mixed together) in a continuous
subcutaneous infusion are:
or hydromorphone – for visceral pain
Scopolamine – for colicky pain (0.8mg to 2.4mg per 24 hours)
Haloperidol – for nausea (5mg to 10mg per 24 hours)
The dose of
opioid analgesic needs to be carefully titrated to the pain,
and will depend on the dose of opioid analgesic that
previously controlled the pain.
persists then stronger anti-emetics are required instead of
haloperidol. Use cyclizine 100mg to 150mg per 24 hours, or
methotrimeprazine 50mg to 100mg per 24 hours. (see
The aim of
symptomatic management is to control pain and nausea,
and to allow fluids and a soft diet. Some food is
absorbed in the upper small bowel above the obstruction.
Occasional short episodes of vomiting once or twice a day may
have to be accepted. Patients usually tolerate vomiting well,
provided they are free of nausea and receive appropriate
softener (docusate sodium syrup 100mg to 200mg every 8 hours)
is given so that if bowel function is restored (which it can
be) constipation is not an additional problem. Stimulant
laxatives should be avoided as they worsen the colic.
This regime can keep patients well hydrated and virtually free
of symptoms for many weeks.
The author and publisher have taken
precautions to ensure that the information in this book is
error-free. However, readers must be guided by their own
personal and professional standards of good practice in
evaluating and applying recommendations made herein. The
contents of this book represent the views and experience of
the author, and not necessarily those of the publisher.