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et al, 2002). Adoption of written guidelines or algorithms for pain management improved both
assessment and management of pain in neonates and children (Falanga et al, 2006 Level IV;
Gharavi et al, 2007). As in adults, other domains of pain (eg location, quality) and the
multidimensional nature of the pain experience (eg concomitant emotional distress, coping
style of the child, previous pain experience) and parental expectations (Liossi et al, 2007) should
be incorporated into overall assessment. Clinical trials have focussed on assessment of pain
intensity and further evaluation and validation of tools for measuring global satisfaction,
adverse effects and physical recovery following paediatric acute pain are required (McGrath et
al, 2008).
Verbal self‐report is considered to be the best measure of pain in adults. Although self‐report
should be used in children whenever possible, it is not always possible as a child’s
understanding of pain and their ability to describe it changes with age. Therefore
measurement tools must be appropriate to the different stages of their development.
Examples of acute pain measurement tools are listed in Tables 10.1, 10.2 and 10.3.
10.3.1 Pain assessment in neonates
A large number of scales have been developed for neonates and infants, encompassing a
number of surrogate measures (eg physical signs such as increased heart rate) or behavioural
responses (eg facial characteristics and cry). Choice of the most appropriate tool depends on
the age of the infant, the stimulus (eg procedural or postoperative pain) and the purpose of
the measurement (eg clinical care or research).
Physiological measures
Changes in physiological parameters associated with procedural interventions are assumed to
indicate the presence of pain, including: increases in heart rate, respiratory rate, blood
pressure, intracranial pressure, cerebral blood flow and palmar sweating; and decreases in
oxygen saturation, transcutaneous carbon dioxide tension and vagal tone (Sweet & McGrath
1998). As these changes are reduced by analgesia, they are useful surrogate outcome
measures of pain, but as their sensitivity and specificity will also be influenced by concurrent
clinical conditions (eg increased heart rate due to sepsis) and other factors (eg distress,
environment, movement), they should be used in conjunction with other behavioural
measures (Howard et al, 2008 Level IV). Cortical pain responses to noxious stimuli can be
demonstrated in premature neonates (Bartocci et al, 2006 Level III‐3; Slater et al, 2006 Level III‐3).
This technique is currently utilised solely as a research tool, but the level of cortical activity has
been shown to correlate with the premature infant pain profile (PIPP) score (Slater et al, 2008
Level IV). CHAPTER 10
Behavioural measures
Noxious stimuli produce a series of behavioural responses in neonates and infants that can be
used as surrogate measures of pain (McGrath, 1998; Gaffney et al, 2003) including crying, changes
in facial activity, movement of torso and limbs, consolability and sleep state. Crying can be
described in terms of its presence or absence, duration and amplitude or pitch.
The reliability and validity of behavioural measures is best established for short sharp pain
associated with procedural interventions such as heel stick. The specificity and sensitivity of
the response can be influenced by previous interventions and handling (Holsti et al, 2006),
motor development, and manifestations of other states of distress (eg hunger and fatigue),
particularly in neonates requiring intensive care (Ranger et al, 2007).
Ten facial actions are included in the Neonatal Facial Coding Scale (NFCS), which was originally
validated for procedural pain in neonates and infants (see Table 10.1) (Grunau & Craig, 1987).
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