Pain is a common symptom seen in patients of all ages and in all health care settings. In children, however, pain assessment may be hindered both by developmental factors and by the way certain features of pain assessment tools uniquely affect a child's response. Inaccurate pain assessment leaves a child vulnerable to prolonged or repeated acute pain, including procedural pain, and to such associated sequelae as subsequent medical traumatic stress, more intense response to subsequent pain, and development of chronic pain, resulting in interference with sleep as well as with academic, social, household, and extracurricular activities.1-6 In comparison, children whose acute or procedural pain is sufficiently relieved may be more likely to experience the type of enhanced development seen in children who undergo "posttraumatic growth" and emerge from traumatic experiences with increased resilience and a feeling that the world is a safe place.7
Optimal pain management and patient outcomes require the use of valid and reliable pain assessments. As a result of the multidimensional nature of pain, its assessment is complex, and pediatric pain assessment may be particularly challenging, depending on the child's level of cognitive development, ability to communicate, and prior experiences of pain.8 This article discusses the factors that can influence a child's report of pain, describes components of a comprehensive pediatric pain assessment, reviews appropriate pain assessment scales for children of different ages and levels of cognitive development, and underscores the potential benefits nurses can reap from partnering with the child's parent or caregiver.
INFLUENCES ON A CHILD'S REPORT OF PAIN
To appropriately assess a child's pain, it's necessary to understand the biological, psychological, and sociocultural factors that affect a child's experience and expression of pain, as presented in George Engel's biopsychosocial model.9 Viewing pain through this lens allows nurses to tailor pain assessment specifically to each child. In addition to physical health, the biopsychosocial model takes into account such factors as the child's age and level of cognitive development, temperament, fear, and previous experiences with pain. All of these factors shape a child's understanding of pain, how they describe their pain, and how they respond to and cope with pain. It is important to note that these influences are not static but dynamic, changing both as the child develops and over the course of a discrete painful experience.
Level of cognitive development, which determines how children perceive the causes and effects of pain, may best be understood through the developmental stages defined by Jean Piaget (see Table 110, 11). For example, infants ages zero to 12 months (defined by Piaget as in the sensorimotor stage) do not understand pain, but they certainly experience it, demonstrate memory of painful experiences, and respond to parental anxiety.10 It's important that infants in this age range receive optimal pain management to prevent adverse psychological and emotional responses to future painful events. At ages two years and older, children's understanding of pain evolves.
An eight-year-old girl recovering from an appendectomy may, when asked, report that she's not in pain, though she's lying on her side holding her flexed knees against her abdomen. Her age places her in Piaget's concrete operational stage, meaning that she has an increased awareness of her pain and can specify its location, but she also fears bodily harm and death. She may not understand what her surgery entailed and may perceive her pain as signaling impending death. The nurse can provide reassurance and calm her fears by providing an age-appropriate explanation of her surgery, her pain, and its treatment.
Fear and prior painful experiences greatly affect a child's perception of painful events and are the primary influential factors in this model. Previous experiences with pain affect how children react to future events that are painful or potentially painful. Higher levels of fear in children have been correlated with higher levels of reported pain, anxiety, persistence of pain, disability, and avoidance behaviors.12, 13 The effects of fear based on prior painful experiences are often observed in toddlers presenting to an urgent care center shortly after vaccine administration. When a nurse approaches a recently vaccinated 18-month-old to clean and dress a superficial laceration, the toddler may withdraw or cry, remembering the pain associated with the shots and anticipating similar pain. In this situation, the nurse should ask the parent whether the toddler had any recent painful experiences in a health care setting, explaining that even having received a vaccination over the past few days may influence a child's response to subsequent health care visits. The nurse can then help the parent comfort and reassure the toddler both before and while providing necessary wound care.
Societal expectations, stereotypical assumptions, and familial cultural norms. Children learn how to experience, cope with, and report pain by observing their parents' and caregivers' responses-and those responses are influenced by societal expectations and stereotypes. This is particularly evident in the way that sex-role socialization occurs within the family, with boys who receive parental cues that it is unacceptable to express pain tending to be less likely to report pain.14 For example, a four-year-old boy recently hospitalized for surgery may fear needles and start to cry when taken to the office of his primary care provider for immunization boosters. If his mother says, "You're a big boy now, and boys don't cry," she reinforces a stereotypical assumption about male behavior that may reinforce sex-role expectations and affect her son's ability to acknowledge, report, and effectively cope with pain.
Given the child's age, which puts him at Piaget's preoperational stage of cognitive development, in which children often perceive pain as punishment, he may plead with his mother, "Don't make me get a shot. I promise I won't get sick again." The nurse administering his injections can then guide the child's mother in distraction techniques that can calm the child's fears and offer him reassurance that shots are not a punishment for being sick but a way to help him stay healthy and feeling well.
Anchor effects occur when the "anchors" (the extremes of a scale) influence the severity of a child's self-reported pain. For example, scales that use a smiling face to depict the bottom anchor ("no pain") or a sad face with tears to depict the top anchor ("most pain") may lead to false-negative or false-positive reports of pain, because children who feel happy are not necessarily pain-free and children in no pain are not necessarily happy.15 Furthermore, pain assessment tools that anchor the pain experience as "no pain" versus "most pain" are often difficult for young children to understand, because the concept of "most" is abstract and relative, depending largely on the child's previous experiences with pain. Numeric or color anchors can also evoke a child's bias, as young children may not understand the quantitative significance of numbers, even if they know how to count, and color scales are not well researched.16 A child may be inclined to pick their favorite color or number rather than the color or number that best corresponds with their pain level.
ELEMENTS OF A COMPREHENSIVE PEDIATRIC PAIN ASSESSMENT
There is a wide range of factors that affect a child's experience of pain, which is why children may behave and respond differently to the same type of painful experience, be it a broken bone, surgical pain, or the pain of immunizations. To take these factors into account in performing a pain assessment, nurses must obtain the child's history of painful experiences and document any chronic pain conditions or current reports of pain.
The child's pain history not only provides context but may also shed light on circumstances that could influence the child's report of pain. Ideally, the history is gathered from both the child and the parent or caregiver either before or during a painful event (see Table 217 for questions to ask when conducting a pain history). For children with a chronic pain condition, nurses need to conduct a more detailed pain history (see Table 38).
PAIN ASSESSMENT TOOLS
After obtaining and documenting the child's pain history, it's necessary to quantify the presence and level of pain, document the need for intervention, and determine the effectiveness of any pain management interventions used.
The following three types of assessment are used to measure pain intensity in children, and a number of tools or scales employ one or more of the three (see Table 41, 16, 17, 19-31):
* physiological
* behavioral-observational
* self-report
Physiological measures of pain include heart rate, respiratory rate, blood pressure, and oxygen saturation. Although embedded in some observational pain assessment tools, physiological measures alone do not discriminate between responses to pain and stress. Additionally, responses to pain measured by these indices wane over time, making their exclusive use an invalid measure of pain.
Behavioral-observational tools allow nurses to monitor observable behaviors that are indicative of pain. They may be used to assess pain in children who are
* too young to self-report.
* distressed.
* restricted by bandages or sedating drugs.
* altering (exaggerating or minimizing) their self-report ratings because of fear.
* sleeping.
Pain assessment should be considered for sleeping children, because children often use distraction (play) to cope with pain but can then become exhausted, fall asleep, and experience persistent pain while sleeping.10, 32 When assessing pain in a sleeping child, use a validated behavioral-observational scale, as these scales are least likely to disrupt the child's sleep. Behavioral-observational scales include the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS)26; the COMFORT Scale1; the Face, Legs, Activity, Cry, Consolability (FLACC) scale27; and the revised FLACC scale.25
Documentation in an established section of the electronic health record should follow each assessment, preferably with a drop-down menu to guide the nurse in scoring.
Self-report measurements of pain are preferred because they provide the most valid measurement of a patient's subjective pain experience and are convenient to use. Their clinical utility is limited, however, by the communication skills of the patient. That being said, children as young as four years of age can often provide a self-report of their pain if provided with a tool appropriate for their age and developmental level. There are several self-report tools that can be used in children of varying ages.
Numeric rating scales require patients to gauge their pain severity using numbers, with 0 representing "no pain" and 10 representing "the most pain possible." These scales may be used to assess pain in children ages eight years and older, provided they understand numbers, have the ability to express pain in quantitative terms, and can communicate verbally.16
Faces scales present children with drawings or photographs of facial expressions representing different levels of pain intensity. Children are asked to select the picture that best represents their pain. These easily reproduced scales require no quantitative reasoning on the part of the child.16 Examples include the Wong-Baker FACES Pain Rating Scale, for use by children ages three to 18 years31; the Faces Pain Scale-Revised (FPS-R), for use by children ages four years and older21; and the Oucher Scale, for use by children ages three to 12 years.19
Visual analog scales (VAS) present children with a horizontal or vertical line, most commonly 100 mm in length, with anchors at each end indicating either "no pain" or "worst possible pain." The child makes a perpendicular mark on the line to indicate pain severity.29 VAS scores demonstrate good interrater reliability and are sensitive to changes in pain following analgesic interventions.33 These tools are appropriate for children eight years or older29 and are easily reproduced, though photocopying may distort the line length.
Adjective scales require patients to select a word out of a list of adjectives that describe pain severity. These scales can be used to assess pain in patients with at least a high school level of verbal fluency, but their use in children is not recommended as it has not been widely studied.16
Graphic rating scales, such as the Pieces of Hurt tool, which is also known as the Poker Chip Tool, invite children to measure their pain intensity using four colored chips, each of which represents a "piece of hurt."16, 17 One chip indicates "a little hurt" and four chips indicate "the most hurt" the child could have. This clinical assessment tool is most useful in determining the presence or absence of pain in young children. It was developed for use in children ages four through seven years, but has been used for acute procedural pain in patients as young as three years and as old as 18.29
SPECIAL POPULATIONS
Children who are cognitively impaired, sedated, or receiving mechanical ventilation, as well as premature infants and neonates, pose additional pain assessment challenges. On the assumption that pain induces alterations in the autonomic nervous system, physiological indicators are often embedded in the scales used to assess pain in these patients.
Cognitively or developmentally delayed children. These children are at elevated risk for undertreated pain owing to their neurologic impairments and limited ability to self-report pain. In addition to physiological cues, behavioral cues-such as facial expressions, vocalizations, changes in posture or movement, alterations in sleeping or eating patterns, feeding intolerance, and changes in mood or sociability, including irritability or reports of "not acting like themselves"-may be used to identify pain in these children.34 For this reason, it's important for nurses to work in partnership with children's caregivers when conducting the initial baseline pain history and subsequent pain assessments. Well-validated tools for this patient population include the Noncommunicating Children's Pain Checklist-Revised (NCCPC-R)20 and the revised FLACC.25
Infants and children who are sedated or receiving mechanical ventilation. Numerous factors influence the expression of pain in these children, making it difficult for caregivers to differentiate pain from distress, anxiety, or agitation. The COMFORT Scale, however, is the only tool validated for assessing pain in mechanically ventilated patients ages zero to 18 years and is particularly useful in pediatric ICUs.1, 35
Premature infants and neonates. These infants may be assessed with tools that combine behavioral and physiological indicators and are specific to such contextual factors as gestational age and sleep-wake state. These tools include the Premature Infant Pain Profile (PIPP),28 Neonatal Infant Pain Score (NIPS),24 Crying, Requires Increased Oxygen Administration, Increased Vital Signs, Expression, Sleeplessness (CRIES) tool,23 and Neonatal Pain, Agitation, and Sedation Scale (N-PASS).22
PAIN ASSESSMENT FREQUENCY AND DOCUMENTATION
When a child is treated in a health care setting, pain should be assessed and documented at all of the following points36, 37:
* with any ED or ambulatory clinic visit
* on admission to the hospital or surgical center
* before, during, and after any procedure
* before and after any pain management intervention
* once per shift in an acute care setting, coinciding with routine assessments and patient care
PARTNERING WITH CAREGIVERS
Involving a child's parents or consistent caregivers is an important aspect of pain assessment and management. Since parents and caregivers are most familiar with a child's typical behavioral response to pain, they can often identify behaviors unique to the child and provide valuable "proxy reports" of the child's pain, though such proxy assessments should be combined with other types of assessment when possible.38 Authors of a small qualitative study that investigated how parents of children with Down syndrome assess pain in their children and intervene to relieve it suggest that it may be even more important to involve parents of children who have difficulties with self-report in interpreting their child's behavior and identifying comfort strategies.39
Researchers studying parents' use of the FLACC scale and a 0 to 10 numeric scale to assess pain in their cognitively impaired children made the following observations, which support both construct and criterion validity of parental proxy pain ratings40:
* Parental ratings using the FLACC scale correlated well with parental ratings using the numeric scale.
* Parental ratings decreased significantly after analgesics had been given to the children.
* There was a high correlation between parents' and nurses' ratings using both tools, though there was slightly more agreement between parents' and nurses' FLACC ratings.
The Royal College of Nursing's clinical practice guideline, The Recognition and Assessment of Acute Pain in Children, defines parental (caregiver) involvement as a principle of practice.41 It states that children and their families should be viewed as partners in care, involved in shared decision making for individualized pain assessments, and provided with training regarding the use of pain assessment tools.
The effectiveness of educating parents or caregivers in pain assessment and management was demonstrated in a 2003 study that included the parents of 51 children undergoing cardiac surgery.42 Parents who were exposed preoperatively to educational material on pain assessment and management significantly increased their knowledge in these areas, as measured by improved pretest to posttest scores. By introducing educational materials that promote advocacy for the child and encouraging optimal communication between health care providers and the family, nurses can better involve parents and caregivers in the pain assessment and management processes.
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