Cancer
Pain Management: Pain is an
important symptom in cancer patients. Cancer Update will feature
a special series by Dr Cynthia Goh, Head of Palliative Medicine,
NCC. Here is the first of the series.
Introduction
The incidence of pain in patients with cancer increases
with stage of disease. In patients with advanced cancer,
60 to 90% have pain. Up to 81% have pain at 2 or more sites,
with one-third of patients reporting pain in 4 or more sites.
Unrelieved pain decreases quality of life, interferes with
function, appetite, sleep and social interactions, and may
lead to depression and a wish to die. Pain is often considered
an ominous symptom by cancer patients, though it may or
may not signify recurrent or progressive disease. Effective
treatment using relatively simple means is available, but
often not achieved because of various patient, physician
and systemic factors.
Evaluation
of Cancer Pain
Good pain management starts
with accurate assessment of the cause, type and pathophysiology
of the pain. Health professionals should routinely ask about
pain in cancer patients, and the patient’s self-report
should be the primary source of assessment. The intensity
and temporal pattern of the pain should be documented using
a validated pain scale, such as the 0 to 10 numeric scale,
a four-point categoric scale or a non-verbal scale, such
as the Wong-Baker faces. (Figure 1) Ongoing assessment is
essential. This should be done at regular intervals, with
each new report of pain, and at suitable intervals after
each intervention, e.g., 15 to 30 minutes after parenteral
therapy or one hour after oral therapy. In patients with
more than one pain, each pain should be assessed and a likely
cause assigned. Factors which may influence the response
to analgesia, such as psychosocial factors and the meaning
of the pain to the patient, should also be evaluated.
Figure 1 Pain Intensity Scales. Example
of a Pain Ruler with Numeric Rating Scale and Verbal Rating
Scale and the Wong-Baker faces for non-verbal adults and
children.
Dr Cynthia Goh
Head, Palliative Medicine
