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CHAPTER 11

Pain Management

Helen Sowerbutts
Kokila Lakhoo

Introduction
Most hospitalized children will experience some pain, either as a result
of disease itself or as a result of interventions. A number of studies have
demonstrated that the management of pain in children is, unfortunately,
often inadequate, especially in the African setting, where resources and
skills are limited and overwhelming acute life-saving events override
pain management.
Accurately assessing pain and treating it accordingly can be
challenging in children due to the different ways in which pain
is expressed in the various age groups, compounded by cultural
and individual differences in the perception of pain. Effective pain
management in children therefore requires much more than just a
sound knowledge of analgesic medications; it requires health care
professionals to be trained and experienced in recognising the degree of
pain being experienced by children of different age groups. Health care
professionals in Africa must be skilled in using pain assessment tools
as well as appreciating the role of social, cultural, and environmental
factors in influencing pain perception. Careful consideration must be
given to how pain can be prevented and minimised when children are in
hospital, and appropriate prescription of analgesics must be combined
with a variety of nonpharmacological methods to improve pain
perception. Availability of appropriate medications is another limiting
factor in African health care systems. 1
Aetiology/Pathophysiology
Pain can be defined as “an unpleasant sensory and emotional experi-
ence associated with actual or potential tissue damage, or described
2
in terms of such damage”. This definition highlights an important
concept that is especially relevant in children: Pain has both neurologi-
cal and higher cognitive components. As a result, the degree of pain
experienced is not necessarily a reflection of the underlying illness. A
relatively minor procedure for one child might cause intense distress for
another. Likewise, the health care worker should not underestimate the
potential severity of the underlying illness in a child who exteriorises
pain to a lesser degree. Factors known to affect a child’s pain perception
include anxiety, expectation, and previous experience, as well as bio-
logical factors such as developmental stage and gender. The role of the
family, religion, and culture has also become increasingly recognised
3
in the West ; however, this role is less recognised in Africa due to other
life-threatening illnesses.
The basic pathways thought to underlie the perception of pain
are shown in Figure 11.1. The pathway was originally described by
4
the Melzack-Wall gate control theory in 1965, which states that the
detection and transmission of pain from the periphery takes place
by A-delta and C nerve fibres that travel to the spinal cord, where a Source: www.perioperativepain.com.
reflex withdrawal arc is triggered. Pain impulses are simultaneously Figure 11.1: Basic pathways involved in the perception of pain.
transmitted up the spinal cord to the thalamus and cortex. Various
ascending and descending pathways from the cortex and reticular
formation allow levels of arousal and higher cognitive functioning to
modify the basic pathway.