[font=Times]Pediatric Chronic Pain
A Position Statement from the American Pain Society
Significance of the problem
Chronic pain is a significant problem in the pediatric population, conservatively estimated to affect 15% to 20% of children (Goodman & McGrath, 1991). Children* and their families experience significant emotional and social consequences as a result of pain and disability. The financial costs of childhood pain also may be significant in terms of healthcare utilization as well as other indirect costs, such as lost wages due to time off work to care for the child (Li & Balint, in press). In addition, the physical and psychological sequelae associated with chronic pain may have an impact on overall health and may predispose for the development of adult chronic pain (Campo et al., 1999; Walker, Garber, Van Slyke, & Greene, 1995).
* This term refers to all individuals in the pediatric age range (i.e., neonates, infants, and adolescents).
Definition of chronic pain
Acute pain follows injury to the body and generally disappears when the bodily injury heals. It is often, but not always, associated with objective physical signs of autonomic nervous system activity. Chronicpain, in contrast to acute pain, rarely is accompanied by signs of sympathetic nervous system arousal. The lack of objective signs may prompt the inexperienced clinician to say the patient does not "look" like he or she is in pain. (American Pain Society, 1999, p. 4)
Chronic pain can be differentiated from acute pain in that acute pain signals a specific nociceptive event and is self-limited. Chronic pain may begin as acute pain, but it continues beyond the normal time expected for resolution of the problem or persists or recurs for other reasons.
Chronic pain in children is the result of a dynamic integration of biological processes, psychological factors, and sociocultural context considered within a developmental trajectory. This category of pain includes persistent (ongoing) and recurrent (episodic) pain with possible fluctuations in severity, quality, regularity, and predictability. Chronic pain can occur in single or multiple body regions and can involve single or multiple organ systems. Ongoing nociception can result in a sensitization of the peripheral and central nervous systems to produce neuroanatomical, neurochemical, and neurophysiological changes. It is important that assessment and treatment strategies be based on this definition and related dimensions.
To evaluate and treat chronic childhood pain efficiently and effectively, the mind-body dualism must be abandoned. It is meaningless to dichotomize chronic pain as organic versus nonorganic because all pain is associated with, at minimum, neurosensory changes. Maintaining this dichotomy is harmful because such faulty thinking leads to over-medicalization (inappropriate investigations, procedures, and interventions) or insufficient acknowledgment of the child's multidimensional experience and underlying neurophysiology.
The International Association for the Study of Pain (IASP) characterized chronic pain as less than 1 month, 1 to 6 months, and greater than 6 months (Task Force on Taxonomy, 1994). Formerly chronic pain was defined as having pain for longer than 6 months. It is now recognized that key elements of chronic pain can be evident much earlier. Definitions also are influenced by developmental factors. For example, recurrent migraine headache that lasts 1 hour in a 4-year-old is typical, whereas headache of this length in adolescents would not likely be classified as a migraine.
Chronic pain may include varying amounts of disability, from none to severe, and may be independent of the amount of tissue damage and perceived severity (Melzack & Wall, 1965). Biological, psychological, social, cultural, and developmental factors can impact pain-related functioning.
An evaluation of a child with chronic pain should include consideration of the biological, psychological, and sociocultural factors in the developmental context (Bursch, Walco, & Zeltzer, 1998).
The evaluation should begin with a history of the current problem, including a careful description of the pain detailing the sensory characteristics, intensity, quality, location, duration, variability, predictability, exacerbating and alleviating factors, and impact of pain on daily life (e.g., sleeping, eating, school, social and physical activities, family and peer interactions). The history, evaluation, and treatment of the current pain problem in terms of its onset and development should be detailed. Inquiry should include the magnitude of distress for the child and family attributed to the pain and the impact of the pain on cognitive functioning, anxiety, depression, and feelings of hopelessness. Assessment also should include what the child and family members perceive as the cause of the pain and how they respond to it. History of past pain problems in the child and in other family members also should be elicited. A review with the family of current treatments for the pain should include inquiry about home remedies and alternative and complementary therapies (Zeltzer, Bush, Chen, & Riveral, 1997a, 1997b).
In addition to the pain history, a typical pediatric history should include medical-surgical history, birth and early childhood history, developmental milestones, social history (i.e., school, friends, interests), and family medical and social history. Particular attention should be paid to recent stressful events, such as deaths, marital disruption, moves, and other changes in life circumstances (e.g., new school).
The physical examination will vary depending on the previous assessments the child has undergone and the specific symptoms. However, the physical examination always should include observation of the child's general appearance, posture, gait, and emotional and cognitive state. Muscle spasms, trigger points, and areas of somatic sensitivity to light touch should be assessed. Vital signs should include height, weight, blood pressure, heart rate, respiratory rate, and temperature. A complete neurological examination should be conducted. It can be helpful to examine the painful area multiple times during the examination. Somatic pain may be elicited when the child tenses his or her muscles due to fear of the examination. It is common for children with chronic pain to develop secondary myofascial pain because of abnormal body posturing and prolonged inactivity. It is helpful to remember that visceral pain, because of its afferent pathways, may be referred to as somatic dermatomes. If significant findings that have not been previously addressed are identified, referral to the appropriate subspecialist is indicated for more thorough evaluation.
Treatment strategies should be based on the findings of the assessment and should address the inciting and contributing factors. A multimodal approach often is more effective than a single sequential treatment approach. This approach includes specific treatment targeting possible underlying pain mechanisms, as well as symptom-focused management addressing pain, sleep disturbance, anxiety, or depressive feelings. For example, a treatment approach for a child with a recalcitrant myofascial shoulder pain might include amitriptyline for facilitating sleep, transcutaneous electrical nerve stimulation (TENS), biofeedback, and massage for pain. Treatment also should address pain-related disability with the goal of maximizing functioning and improving quality of life. For example, partial or complete return to school should often be an early target of treatment for children with pain-related school absenteeism.
Treatment techniques include education about the pain experience and the pain problem, cognitive-behavioral (e.g., self-regulatory behaviors such as hypnosis or biofeedback) strategies, behavioral techniques (e.g., reinforcement), family interventions, physical interventions (e.g., massage, acupuncture, TENS, physical therapy, occupational therapy), and systemic and regional pharmacological interventions (e.g., opioid and non-opioid analgesics, anesthetics, anxiolytics, antidepressants, anticonvulsants, hypnotics, alpha-adrenergic blockers, etc.). Whenever possible, oral routes for medication are preferable. Referral to a pediatric pain program should be considered for children with complex or refractory problems.
Evidence-based treatments should be used whenever available. For example, in adolescent migraine headache, cognitive behavioral interventions have better evidence for efficacy than triptans (Hermann, Kim, & Blanchard, 1995) and ibuprofen seems to be more effective than acetaminophen (Hamalainen, Hoppu, Valkeila, & Santavuori, 1997). Most of the currently employed pharmacological strategies are extrapolated from adult trials without evidence of efficacy in children. Controlled trials are needed to address safety and efficacy in this population.
Specific pain conditions and treatments
Although the previously mentioned treatment strategies apply to all children with chronic pain, more detailed discussion can be found in the references organized by topic at the end of this document.
Pain management should be part of the educational curriculum of all health professionals who care for children. For example, assessment and management of chronic pain in children should be a mandatory part of pediatric residency. Multidisciplinary pediatric pain programs are a particularly valuable resource for this training.
Education of the public will increase community awareness and support of children with chronic pain and shape appropriate public policy. Mass media coverage of chronic pain in children should be promoted (Kuttner, 1996; McGrath, Finley, & Turner, 1992). School staff may benefit from education to facilitate reintegration and support of children with chronic pain in the classroom.
More research is needed to provide evidence-based treatments in chronic pediatric pain. Targeted government and private funding for research in pediatric chronic pain should be augmented. Such funding would not only benefit children with pain and their families, but also would be relevant, in the long term, for reducing the enormous costs of adult chronic pain (Walco & Harkins, 1999). The treatment of chronic pediatric pain would benefit from the development and support of cooperative pediatric chronic pain research consortia.
Examples of key scientific areas that need to be developed include epidemiology, nosology, clinical science (including clinical trials), developmental neurobiology, health services research, sociocultural studies, developmental pharmacology, the developmental psychology of pediatric pain, and the relationship between pediatric and adult chronic pain.
Clinical studies should include detailed attention to definition of populations, measurement of pain and distress, documentation of interventions, family factors, culture, gender, and developmental variables such as pubertal status and cognitive function. Outcome variables should be broad and include measures of pain and distress, function, quality of life, and healthcare utilization.
Children with chronic pain should have access to appropriate services, and children with complex or refractory chronic pain should be referred directly to pediatric pain programs when possible. Many pain approaches validated on adults that lack a developmental and family focus may be inappropriate or even potentially harmful for children with chronic pain.
Reimbursement policies should reflect the multidisciplinary complexity and efforts required to assess and treat children with chronic pain. Comprehensive integrated treatment of medical, psychological, and social factors may be the most cost-effective in the treatment of complex and refractory pediatric pain problems.