Pain is a chief complaint in more than 50% of patients seen for urgent visists.1 Pain and anxiety are poorly assessed and undertreated in children as compared to adults.2,3 An infant or young child cannot verbalize pain, and even as the child becomes verbal they may have difficulty expressing pain or anxiety. Studies have shown that inadequate management of pain has serious implications for future posttraumatic stress disorder, needle phobia, and vaccination rates.4,5 Painful experiences can adversely affect a child's coping mechanisms and pain perception. The first step in the treatment of pain is assessment. Validated pain assessment tools are vital to the recognition and subsequent management of pain and anxiety in infants, children, and adolescents.6 Pain scales in pediatrics must be age appropriate to allow for accurate assessment of pain.
Pain assessment remains a challenging task in pediatrics and contributes to underrecognition of pain. Various scales exist but their use must be age appropriate. Children are unable to express their pain, and their perception of pain contributes to increased anxiety. The American Academy of Pediatrics mandates pain assessments in hospital patients.7 However, there are no widely studied outpatient scales to assess pain outside of the hospital. Thus, a brief review of the most commonly used scales in outpatient practice is provided here.
For infants, nonverbal young children, and patients with cognitive impairment, the face, legs, activity, crying, and consolability (FLACC) scale or the revised FLACC scale can be used (Table 1). Each category is scored on a scale from 0–2, which results in a total score of 0–10; 0 is relaxed and comfortable, 1–3 is mild discomfort, 4–6 is moderate pain, and 7–10 is severe discomfort.8
Faces, Legs, Activity, Cry, and Consolability Scale
Children age 3 years and older without developmental delays are able to use the Faces Pain Scale-Revised (FPS-R) (Figure 1). According to the International Association for the Study of Pain, these faces show how much something can hurt. The face furthest to the left shows no pain. The faces show increasing pain as you progress right. The chosen faces are scored 0, 2, 4, 6, 8, or 10, counting from left to right, so 0 indicates “no pain” and 10 indicates “very much pain”. This scale is intended to measure how children feel inside, not how their face looks.9 This scale has the advantages of showing less emotion than the Wong-Baker FACES Pain Scale, which is anchored with a “smiling” face at 0 and a “crying tears” face at 5.10
Faces Pain Scale-Revised. Reprinted with permission of the International Association for the Study of Pain.9
Adolescents may use the adult numerical scales for their assessment of pain (0 for no pain and 10 for very painful), which has been validated for the acute and procedural setting.11
Strategies for Pain Management
First Step: Nonpharmacologic Techniques
Nonpharmacologic measures have gained acceptance, as there is an increased recognition of the adverse effects of painful procedures on long-term pain perception and coping mechanisms.7 A painful or anxiety-provoking procedure in a child can affect future pain with the subsequent procedure causing more anxiety, irrespective of the degree of pain. The theory of posttraumatic stress symptoms has also been demonstrated in the neonatal population, with researchers demonstrating increased stress-related markers and elevated free radicals after even simple procedures such as routine heel punctures. These posttraumatic sequelae in neonates include physiologic instability, altered brain development, and abnormal neurodevelopment of somatosensory and stress response systems, which can persist into childhood.12
The medical team caring for a child should be oriented to the different types of nonpharmacologic interventions and their role in improving the patient's and their family's experience in the primary care office. Cognitive and behavioral interventions should begin prior to a child entering their assigned examination or procedure room. An inviting environment can be created by the use of child-friendly images on the walls and ceilings as well as hiding or decorating medical equipment that may be perceived as threatening to a child. Prior to the intended procedure, the family should be educated on the procedure as well as techniques such as distraction that will divert the child's attention. The presence of a parent during the procedure can also decrease anxiety, particularly in younger children. Medical personnel should check on prior experiences that may have caused the child distress and techniques that may have helped in the past.
Distraction interventions may be cognitive, behavioral, or sensory. It is important that interventions are specific to age and developmental level. These techniques can be further characterized into active or passive distractions. An active distraction is one in which the child is interacting (eg, a game on an electronic tablet).13 A passive distraction is one in which the medical personnel is providing the distraction (eg, medical staff reflecting images on the wall or blowing bubbles). Passive distractions will work best in procedures where child needs to remain still.14
Infants respond well to sensory distractions such as swaddling or nonnutritive sucking with or without sucrose water.15,16 Toddlers and preschool children will respond best to behavioral distractions with toy that provide lights or sounds, interactive computer applications via an electronic tablet, or playing simple games such as blowing bubbles. Older children and adolescents may benefit from guided imagery on an electronic tablet, relaxation techniques such as rhythmic breathing, or music therapy.7 Child life therapists are cognitive behavioral specialists who are usually employed in children's hospitals. Economic constraints may not allow for a dedicated child specialist in the outpatient setting but medical personnel can be educated on the techniques described here.
Second Step: Topical and Transdermal Adjuncts
Topical agents. The American Academy of Pediatrics recommends topical pain control for patients undergoing procedures such as venipuncture, intravenous (IV) line placement, and abscess drainage.7 Topical anesthetics are used to reversibly block pain conduction causing a temporary loss of sensation.17 One of the most widely available topical formulations is eutectic mixture of local anesthetics consisting of lidocaine 2.5% and prilocaine 2.5%. Evidence supports reduction of pain with IV catheter insertion when applied for a minimum of 45 minutes.18 It can be left on the skin for up to 4 hours, the effect lasts 1 hour after removal, and it improves venipuncture success.19 Due to the potential for methemoglobinemia in preterm infants, it is not recommended in infants younger than age 37 weeks gestational age. A 4% lidocaine topical agent has the advantage of effect within 30 minutes, and it works as well as the combination of lidocaine 2.5% and prilocaine 2.5% for venipuncture pain. It has been shown to improve cannulation success as well.20
Tetracaine gel, as also known as amethocaine, is available alone and compounded with lidocaine. The 4% formulation works in 30 to 45 minutes and lasts 4 to 6 hours with an efficacy similar to the combination of lidocaine 2.5% and prilocaine 2.5%.21
Transdermal lidocaine. Jet-injected lidocaine places lidocaine under the skin when activated using a compressed burst of carbon dioxide. Studies have found the needle-free delivery system less painful for IV cannulation than lidocaine 2.5% and prilocaine 2.5% cream or vapocoolant spray.22,23 Lidocaine powder can also be injected via devices in which the released gas propels 0.5 mg of lidocaine powder into an area of skin 2 cm in diameter.24
Vibration devices and cold spray. Applying vapocoolant spray to the penetration site has been used for venipuncture and IV placement, although placebo-controlled randomized trials have produced varying results for venipuncture success.25 A device that combines an ice pack with a vibration device that can be placed proximal to the site of cannulation can decrease pain by one-half compared with cold spray and also increases IV success.26 This device is as effective as 4% topical lidocaine cream for reducing pain and distress associated with IV cannulation, and it allows the procedure to be completed more than 30 minutes faster than when lidocaine cream is used.27
Topical and injectable options for laceration repair. Open lacerations allow for more rapid medication absorption than intact skin, thus lidocaine, epinephrine, and tetracaine (LET) topical preparations can be used and are the standard for pediatric wound repair.7 These preparations can be made by the in-hospital pharmacy as a liquid or gel preparation, and they provide sufficient wound anesthesia in 20 to 30 minutes.28 A LET-soaked cotton swab may be applied directly in the wound before irrigation and repair. The solution or gel can be held in place with an occlusive dressing, tape, or bandage. Numbness should occur when the tissues blanch and should be tested prior to repair. If continued sensitivity exists, an additional swab may be held in place for 5 minutes prior to repair. LET alone has been shown to provide pain control for 70% to 90% of pediatric facial lacerations.29,30 In extremities, LET has decreased efficacy (by approximately 50%) but has not been shown to cause digital ischemia.31 When local infiltration of lidocaine is needed, both the tissue disruption from the volume of infiltrate and the acidic pH of lidocaine can cause increased pain. Techniques such as buffering the lidocaine with the addition of bicarbonate in a 9:1 ratio, warming the lidocaine before injection, and injecting slowly with a small-gauge needle (eg, 27 gauge) have all been shown to decrease pain.32 Infiltration should be initiated from within the wound, not through the adjacent intact skin. When possible, tapping or vibrating a bit proximal to the site of infiltration can decrease the pain of injection, similar to jiggling a patient's cheek when performing a dental injection.
Minimally invasive wound repair. Tissue adhesives such as 2-octyl cyanoacrylate provide nearly painless closure for low-tension wounds but should be avoided in dirty wounds such as an animal bite.33 Care must be taken to irrigate extensively to avoid infection. Wound-closure strips provide similar painless closure and provide an equivalent cosmetic outcome when used appropriately.34 In general, absorbable sutures should be considered for facial wounds that must be sutured to avoid the pain and anxiety produced by suture removal.35 Wounds of the scalp may be treated with the hair apposition technique for equivalent cosmetic outcomes to staples and improved satisfaction.36 This technique involves taking small clumps of hair on the opposite side of the lacerations and gently pull together to approximate the wound edges. After cleaning the wound and achieving hemostasis, the small clumps are twisted together with a single twist to secure the hair and wound in place with tissue adhesive.
Abscess drainage. Incision and drainage is increasingly being performed under procedural sedation due to the extreme pain caused by the tissue inflammation.37 Using a combination of topical anesthetic (over intact skin) and oral pain medication may reduce the pain. Placement of 4% lidocaine also may lead to spontaneous drainage and decrease the necessity for procedural sedation.38
Third Step: Analgesic Agents—Oral and Transmucosal
When a child is experiencing more severe pain, oral or transmucosal agents should be used. The ideal analgesic agent is one that allows for simple and painless administration. This drug should have effective analgesic properties while allowing for a high degree of safety with a low side-effect profile. It is important to know the onset of action as well as duration of medication effects when choosing an agent for an intended procedure.7,39
Oral analgesia in toddlers, children, and adolescents can be divided into opioid and nonopioid agents. Nonopioid agents such as acetaminophen or ibuprofen work best when they are given at least 20 minutes prior to a procedure, with peak effect at about 1 hour. They should be used to treat mild pain (Table 2). In addition to analgesia, these drugs provide antipyretic and anti-inflammatory properties as well. Acetaminophen should be avoided in children with liver disease. Nonsteroidal anti-inflammatory drugs including ibuprofen and naproxen should be avoided in patients with acute bleeding or bleeding disorder, renal insufficiency, or upcoming surgery.
Common Pediatric Analgesic Agents
Opioid pain management in the outpatient setting should be reserved for severe pain or invasive office procedures such as an incision and drainage or bone fractures. Oxycodone and hydrocodone have an onset of action within 10 to 15 minutes, with a peak effect within 30 minutes. It is important to note that all opioids can cause respiratory depression but most may be used safely in acute pediatric pain management as long as guidelines on dosing are followed. In April 2017, the US Food and Drug Administration (FDA) issued a safety alert restricting the use of codeine and tramadol in children. Those at most risk are children younger than age 12 years and adolescents younger than age 18 years with severe lung disease, obesity, or obstructive sleep apnea.40 This population should not use these medications due to their predisposition for respiratory depression and subsequent death. The FDA is also recommending against the use of codeine and tramadol medicines in breast-feeding mothers due to possible harm to their infants, including excess sleepiness, serious breathing problems, or death.41
The Future: Intranasal Adjuncts
The intranasal route offers direct drug transport into the central nervous system circulation and is maximized by using an atomizer. Intranasal administration largely bypasses hepatic first-pass metabolism and permits rapid and predictable bioavailability compared with oral medications and some intramuscular medications.42 Intranasal fentanyl is appropriate for use in children who do not have or need intravenous access prior to a procedure in the primary care setting. This is helpful in rapidly managing pain for patients requiring transfer for further management, as in the case of a displaced fracture. When fentanyl is administered intranasally, its bioavailability is 89% with onset in children between 6 and 7 minutes and a duration of action of 30 to 60 minutes.42 Side effects are similar to other opioid agents and include nausea, vomiting, lightheadedness, and mild respiratory depression. Various studies have been done in pediatric populations, mostly in children older than age 3 years with acute orthopedic trauma, and all have shown minimal to no adverse events.
The outpatient setting presents many challenges to optimal management of pain and anxiety in pediatric patients. However, as we learn to better understand and assess pain in the pediatric population there are various measures we can take to improve the experience of our patients and families. The outpatient office allows for nonpharmacologic as well as topical, transmucosal, and oral agents to provide pain and anxiety management. Educating team members in the primary care office on recognition of pain and a systemic approach to therapies can allow for an improved patient experience and parental satisfaction.
- Cordell WH, Keene KK, Giles BK, Jones JB, Jones JH, Brizendine EJ. The high prevalence of pain in emergency medical care. Am J Emerg Med. 2002;20:165–169. doi:10.1053/ajem.2002.32643 [CrossRef]
- Brown JC, Klein EJ, Lewis CW, et al. Emergency department analgesia for fracture pain. Ann Emerg Med. 2003;42(2):197–205. doi:. doi:10.1067/mem.2003.275 [CrossRef]
- Drendel AL, Brousseau DC, Gorelick MH. Pain assessment for pediatric patients in the emergency department. Pediatrics. 2006;117:1511–1518. doi:. doi:10.1542/peds.2005-2046 [CrossRef]
- Taddio A, Ipp M, Thivakaran S, et al. Survey of the prevalence of immunization non-compliance due to needle fears in children and adults. Vaccine. 2012;30:4807–4812. doi:. doi:10.1016/j.vaccine.2012.05.011 [CrossRef]
- Baxter AL, Cohen LL, Burton M, Mohammed A, Lawson ML. The number of injected same-day preschool vaccines relates to preadolescent needle fear and HPV uptake. Vaccine. 2017;35(33):4213–4219. doi:. doi:10.1016/j.vaccine.2017.06.029 [CrossRef]
- American Academy of Pediatrics.Committee on Psychosocial Aspects of Child and Family HealthTask Force on Pain in Infants, Children, and Adolescents. The assessment and management of acute pain in infants, children, and adolescents. Pediatrics. 2001;108(3):793–797. doi:10.1542/peds.108.3.793 [CrossRef]
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- Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S. The FLACC: a behavioral scale for scoring postoperative pain in young children. Pediatr Nurs. 1997;23(3):293–297.
- Hicks CL, von Baeyer CL, Spafford P, van Korlaar I, Goodenough B. The Faces Pain Scale-Revised: toward a common metric in pediatric pain measurement. Pain. 2001;93(2):173–183. doi:10.1016/S0304-3959(01)00314-1 [CrossRef]
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- von Baeyer CL, Spagrud LJ, McCormick JC, Choo E, Neville K, Connelly MA. Three new datasets supporting use of the Numerical Rating Scale (NRS-11) for children's self-reports of pain intensity. Pain. 2009;143(3):223–227. doi:. doi:10.1016/j.pain.2009.03.002 [CrossRef]
- American Academy of PediatricsCommittee on Fetus and Newborn and Section on Anesthesiology and Pain Medicine. Prevention and management of procedural pain in the neonate: an update. Pediatrics. 2016;137(2):e20154271. doi:. doi:10.1542/peds.2015-4271 [CrossRef]
- McQueen A, Cress C, Tothy A. Using a table computer during pediatric procedures: a case series and review of the “apps.”Pediatr Emerg Care. 2012;28(7):712–714. doi:. doi:10.1097/PEC.0b013e31825d24eb [CrossRef]
- Tobias JD, Cravero JP, eds. Procedural Sedation for Infants, Children, and Adolescents. Elk Grove Village, IL: American Academy of Pediatrics; 2016.
- Stevens B, Yamada J, Ohlsson A, Haliburton S, Shorkey A. Sucrose for analgesia in newborn infants undergoing painful procedures. Cochrane Database Syst Rev. 2016;7:CD001069. doi:10.1002/14651858.CD001069.pub5 [CrossRef].
- Johnston C, Campbell-Yeo M, Disher T, et al. Skin-to-skin care for procedural pain in neonates. Cochrane Database Syst Rev. 2017;16(2):CD008435. doi:10.1002/14651858.CD008435.pub3 [CrossRef].
- Kumar M, Chawla R, Goyal M. Topical anesthesia. J Anaesthesiol Clin Pharmacol. 2015;31(4):450–456. doi:. doi:10.4103/0970-9185.169049 [CrossRef]
- Cordoni A, Cordoni LE. Eutectic mixture of local anesthetics reduces pain during intravenous catheter insertion in the pediatric patient. Clin J Pain. 2001;17(2):115–118. doi:10.1097/00002508-200106000-00003 [CrossRef]
- Baxter AL, Ewing PH, Young GB, Ware A, Evans N, Manworren RCB. EMLA application exceeding two hours improves pediatric emergency department venipuncture success. Adv Emerg Nurs J. 2013;35(1):67–75. doi:. doi:10.1097/TME.0b013e31827f50cb [CrossRef]
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- Lunoe MM, Drendel AL, Levas MN, et al. A randomized clinical trial of jet-injected lidocaine to reduce venipuncture pain for young children. Ann Emerg Med. 2015;66(5):466–474. doi:. doi:10.1016/j.annemergmed.2015.04.003 [CrossRef]
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Faces, Legs, Activity, Cry, and Consolability Scale
||No particular expression or smile
||Occasional grimace or frown, withdrawn, disinterested
||Frequent to constant frown, clenched jaw, quivering chin
||Normal position or relaxed
||Uneasy, restless, tense
||Kicking or legs drawn up
||Lying quietly, normal position, moves easily
||Squirming, shifting back and forth, tense
||Arched, rigid, or jerking
||No cry (awake or asleep)
||Moans or whimpers, occasional complaint
||Crying steadily, screams or sobs, frequent complaints
||Reassured by occasional touching, hugging or being talked to, distractible
||Difficult to console or comfort
Common Pediatric Analgesic Agents
||Typical Initial Maximum Dosea
||15 mg/kg every 4 hours
20 mg/kg every 6 hours
||Not to exceed
75 mg/kg/day or 3,000 mg/day
||10 mg/kg every 6 hours
||Not to exceed
40 mg/kg/day or 2,400 mg/day
Not recommended in infants <6 months
||0.1–0.2 mg/kg every 4 hours
||May use higher dose in opioid-tolerant patients
||0.1–0.2 mg/kg every 4 hours
||May use higher dose in opioid-tolerant patients
||Dose limited to 1 mL maximum volume per nare