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Postoperative Pain Management in Children of Hispanic Origin: A Descriptive Cohort Study

Brown, Rebecca BS*; Fortier, Michelle A. PhD*†; Zolghadr, Sheeva BS*; Gulur, Padma MD*; Jenkins, Brooke N. MS*; Kain, Zeev N. MD, MBA*‡§

doi: 10.1213/ANE.0000000000001042
Pediatric Anesthesiology: Research Report

BACKGROUND: It has been established that pain is frequently undertreated in children following outpatient surgery. Very few studies, however, have investigated this phenomenon in ethnically diverse populations.

METHODS: This study included 105 families of children aged 2 to 15 years of Hispanic origin and low income undergoing outpatient tonsillectomy and adenoidectomy surgery. Participating parents completed baseline and demographic packets. Recorded postoperative pain ratings and administration of analgesics at home for 1 week were collected during home visits.

RESULTS: Despite the high (70%; 99% confidence interval [CI], 57%–82%) incidence of significant pain in the first 24 hours home, 32% (95% CI, 20%–45%) of the children received 0 to 1 dose of analgesia. Overall, 21% children (99% CI, 11%–35%) received 4 or less total doses of pain medication over the entire week after surgery. Of the total analgesic doses administered to children in the week after surgery, only 44% (99% CI, 40%–47%) were in accepted ranges.

CONCLUSIONS: Despite experiencing significant postoperative pain, Hispanic children assessed in this study received suboptimal analgesic therapy at home.

Published ahead of print October 26, 2015

From the *Department of Anesthesiology and Perioperative Care, University of California, Irvine, California; Department of Pediatric Psychology, CHOC Children’s Hospital, Orange, California; Department of Pediatrics, CHOC Children’s Hospital Orange and University of California, Irvine, California; and §Child Study Center, Yale University School of Medicine, New Haven, Connecticut.

Accepted for publication August 27, 2015.

Published ahead of print October 26, 2015

Funding: Supported by grant number R21HD071798 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Eunice Kennedy Shriver National Institute of Child Health and Human Development or the National Institutes of Health.

The authors declare no conflicts of interest.

Reprints will not be available from the authors.

Address correspondence to Michelle A. Fortier, PhD, UCI Center on Stress and Health, 505 S. Main St., Suite 940, Orange, CA 92868. Address e-mail to mfortier@uci.edu.

Medical advances in recent years have allowed an increasing proportion of pediatric surgery to be performed in the outpatient setting, transitioning responsibility of postoperative pain management to parents in the home setting.1 To adequately treat pain associated with these procedures, the American Society of Anesthesiologists (ASA) recommends that caregivers use proactive, around-the-clock treatment regimens, inclusive of developmentally appropriate analgesic therapy.2 Unfortunately, there is a significant gap in the translation of these practice guidelines to pain management in the home setting. Specifically, in a previous study published in Pediatrics in 2009,3 we examined children’s pain levels and parental pain management practices at home after surgery. In this sample, we identified a significant discrepancy between parent perception of high postoperative pain and low dosing of analgesics. As is the case with other pediatric pain studies, however, this previous study included a minimally diverse population (77% non-Hispanic Caucasian) and thus has restricted external validity of the study to populations of diverse ethnicities and races.

Although a substantial body of literature has recognized ethnic and racial disparities in pain in adults, few studies have assessed the impact of cultural factors on the pain experience of children.4–8 This gap in current literature necessitates further investigation, especially considering the growing Hispanic population in the United States.9 It has been suggested that Hispanic cultural values, including a tendency toward stoicism and subsequent inhibition of behaviors that may burden others, may put Hispanic patients at risk for undertreatment of pain.10 In addition, Hispanic families may be more likely to experience systems-based barriers to optimal pain management such as lower socioeconomic status (SES) or lower health literacy relative to their non-Hispanic Caucasian counterparts.7,11 Indeed, a previous study by our research program found that Hispanic parents were significantly more likely to demonstrate misconceptions regarding analgesics (e.g., issues of addiction, fear of side effects) and pain expression in children compared with non-Hispanic Caucasian parents.12,13 Given our findings that these parental misconceptions are related to undertreatment of children’s postoperative pain,14 we suggest that Hispanic children of lower SES may be highly vulnerable to inadequate pain management at home. Therefore, the purpose of this present investigation was to systematically examine postoperative pain management patterns within a large population of Hispanic children of low SES.

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METHODS

IRB/Consent

The Children’s Hospital of Orange County (CHOC Children’s) IRB approved the study. Written informed consent was obtained from all participants or the parents or legal guardians for minor subjects in their primary language.

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Clinical Trial Registration

This study did not involve assigning patients to treatment groups.

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Participants

This National Institutes of Health–supported study was conducted at CHOC Children’s during the years 2011 to 2013. The study included a cohort of 197 children aged 2 to 15 years who were scheduled to undergo outpatient ENT, general, orthopedic, and urologic surgery. Only Hispanic children whose parent(s) were English- or Spanish-speaking and of lower SES as defined by federal poverty guidelines were eligible for participation in the study. Exclusion criteria included ASA physical status III or IV and a history of developmental delay, chronic illness, and premature birth. The exclusion criteria were used to standardize the sample because physical and emotional impairments can contribute to confounding variations in pain sensitivity and emotional response to surgery and to challenges in pain evaluation.

To control for variations in surgical severity and postoperative pain, the present report only includes data of children from the larger cohort undergoing outpatient tonsillectomy and adenoidectomy (T&A). Of the original sample of 197 children, 70 had a surgical procedure that was not a T&A and were therefore not included in the analyses, resulting in a sample size of 127. Of the 127 children undergoing T&A and their parents who agreed to participate in the study, 22 dropped out (were lost to follow-up or did not return an adequate number of home surveys), yielding 105 who completed postoperative pain and analgesia follow-up monitoring.

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Measures

Patient Characteristics: Acculturation Rating Scale for Mexican Americans-II

The Acculturation Rating Scale for Mexican Americans-II (ARSMA-II) is used to assess multidimensional orientation toward Mexican and Anglican culture.15 Through a self-report questionnaire on aspects of daily living (e.g., “I think in Spanish/English,” “I enjoy English/Spanish language TV”), ARSMA-II generates scores along 2 linear subscales: an Anglo-Orientation Subscale and Mexican-Orientation Subscale. Respondents are then categorically scaled into 5 acculturation groups: very Mexican oriented, Mexican oriented to bicultural, Anglo oriented to bicultural, strongly Anglo oriented, and very assimilated. These groups note degrees of assimilation or loss of Mexican cultural identity as Anglican culture is acquired and development of bicultural orientation. Generational status is also noted in this survey, with “first generation” representing individuals born in Mexico or another country; “second generation” representing individuals born in the United States with at least one parent born in another country; and so on. Although the questionnaire is specific to Mexican-American culture, it has demonstrated functionality as a measure of acculturation in other Hispanic cultural groups and is frequently used as such.16,17 In addition, the majority of the cohort in the present study was of Mexican background.

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Child Pain Report: Faces Pain Scale-Revised

The Faces Pain Scale-Revised (FPS-R) is a self-report measure used to assess pain in children.18 Children are provided a schematic with 5 facial expressions ranging from neutral (“no pain”) to the one representative of the “worst pain ever” and prompted to indicate that which best represents how they feel. A cutoff score of 3 (of 10) is considered representative of clinically significant pain. This measure has demonstrated excellent convergent validity with other pain scales.19,20 FPS-R is widely validated for children aged 4 years and older.20

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Analgesic Administration

Parents recorded the type (i.e., acetaminophen, ibuprofen, hydrocodone, and codeine), strength, and quantity of pain medication given to their children on postoperative days 1 through 7. To provide real-time assessment of pain management, parents also recorded the time each dose was administered.

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Procedure

Potential participants were identified through surgery schedules, and eligibility was assessed by review of electronic medical records for exclusionary criteria. Families were approached in the preoperative holding area by a bilingual research associate and were provided an information sheet and verbal description of the study. After parents provided informed consent and children gave appropriate assent, participants indicated their preferred language for written information and were provided demographic and baseline surveys.

All T&A procedures were performed by a single surgeon. After surgery, children were taken to the postanesthesia care unit (PACU) where pain assessment and analgesia administration were completed by nurses consistent with hospital standard of care. Surgical technique and pain management were not standardized to maintain external validity. Before discharge, research associates provided parents with a home packet containing record forms for assessing children’s pain severity and analgesic administration on each of the postoperative days. Research associates reviewed record forms with parents and verbalized how to administer FPS-R and demonstrated with the actual measure. All patients were discharged home directly from the PACU within 3 hours of surgery. Upon discharge, caretakers received verbal and standard written analgesic instructions for the management of postoperative pain at home by the PACU nurse. The instructions advised around-the-clock administration of acetaminophen by mouth or rectum as directed on medication packaging. In addition, caregivers were instructed to give codeine or hydrocodone every 3 to 4 hours as needed if patients actively reported pain.

At home, parents completed daily pain medication record forms for 1 week after surgery describing all analgesics given within each 24-hour period. Parents were also asked to obtain their child’s self-report of average pain intensity over the course of each day through administration of FPS-R. Parents recorded this single-daily FPS-R pain score in the provided pain record packets. If no pain medication was given on any of the postoperative days, parents were asked to indicate the reason (e.g., child not in pain, child refused medication, and no medication prescribed).

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Data Analysis Strategy

Descriptive statistics were used to analyze demographics, baseline characteristics, and the 2 primary outcomes of this study: postoperative pain intensity and analgesic administration at home. Normally distributed statistics are reported as means and SDs, and skewed data are reported as medians and interquartile ranges (IQRs). Pain intensity was analyzed such that FPS-R scores ≥3 defined clinically significant pain. One-sample t tests were used to compare FPS-R scores to this cutoff value. This allowed us to determine whether the sample on average experienced clinically significant pain. To determine whether children received accepted doses of analgesics, all individual medication doses reported by parents were converted to milligrams and divided by the child’s weight obtained from hospital records. The normalized doses were then categorized as accepted or subaccepted by using the following cutoff values: acetaminophen at 10 mg/kg/dose, ibuprofen at 5 mg/kg/dose, codeine at 0.5 mg/kg/dose, and hydrocodone at 0.1 mg/kg/dose. The doses were then further subgrouped as markedly subaccepted and moderately subaccepted. Given the patterns of pain recovery found in previous literature,3,21 analysis of pain assessment and frequency of analgesic administration were focused on postoperative days 1 to 3 and week 1. Using the Clopper-Pearson method, 99% confidence intervals are provided on all point estimates.22,23 All study analysis was performed using SPSS 20.0 (IBM, Armonk, NY).

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RESULTS

Descriptive Data

Table 1

Table 1

Table 1 presents the demographic and baseline characteristics of 105 participating patients and parents who completed the survey packets and pain and analgesic records. Strong Hispanic cultural identity was prevalent in this sample. Most parents were born in Mexico and spoke primarily Spanish (74%). Just 3 parents who completed the survey and pain and analgesic records were not of Hispanic background (all children included in the study were Hispanic). Of the Spanish speakers, 64% indicated English as a second language. ARSMA-II responses defined 48% of parents as “very Mexican oriented,” 33% of parents as “Mexican oriented to bicultural,” and 19% as “slightly Anglo oriented.” One-way analyses of variance were performed to examine acculturation group differences in pain report and analgesic dosing. No significant patterns emerged among these outcome variables within this cohort.

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Pain Assessment at Home

Figure 1

Figure 1

Figure 1 presents the percentage of children experiencing clinically significant pain on postoperative days 1 to 3 and week 1, as assessed by child self-report (FPS-R). FPS-R scores classified the peak percentage (70%; 99% CI, 57%–82%) of children in significant pain in the first 24 hours after surgery (IQR, 2–6). Parents recorded children as reporting clinically significant pain on the first 2 postoperative days (day 1: 70% experienced clinically significant pain: 99% CI, 57%–82%; t(90) = 6.05; P < 0.001; 95% CI, 1.20–2.38; day 2: 64% experienced clinically significant pain, 99% CI, 53%–80%; t(85) = 5.393; P < 0.001; 95% CI, 1.03–2.23, with incremental improvements in pain through the week). By 1 week after surgery, 28% (99% CI, 16%–42%) of children remained in clinically significant pain (IQR, 0–4).

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Frequency of Analgesic Administration by Parents

Figure 2

Figure 2

Figure 2 displays the frequency of analgesic doses administered to children on postoperative days 1 to 3 and week 1. Overall, 21% of children (99% CI, 11%–35%) received 4 or less total doses of pain medication over the entire week after surgery. The median total analgesic dose frequency delivered to children over the first 3 days was 7 (3–9). Thirty-two percent of children (99% CI, 20%–45%) received 0 or just 1 dose of analgesia on the first postoperative day at home. On day 3 after surgery, a large portion of children (39%; 99% CI, 26%–52%) received 0 or 1 dose of analgesia despite 56% of children (99% CI, 41%–70%) self-reporting significant pain to parents through FPS-R. On days 1, 2, 3, and week 1 after surgery, 18, 20, 16, and 12 children received at least 1 dose of opioid pain medication, respectively.

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Accepted Dosing

Table 2

Table 2

Table 2 presents the median doses of analgesia given by parents in aggregate over postoperative week 1, as well as the distribution of accepted, moderately subaccepted, and severely subaccepted doses administered over that time. Overall, the majority of normalized (mg/kg) analgesic doses were subaccepted: only 44% (99% CI, 40%–47%) were in accepted ranges. Acetaminophen was the most common drug administered by parents, comprising 78.4% (99% CI, 75%–81%) of the total doses given. However, only 40.7% (99% CI, 36.7%–44.8%) of acetaminophen doses were in the accepted range and 9.6% (99% CI, 7.3%–12.2%) of doses were markedly low (<5.0 mg/kg). Ibuprofen was the only drug for which the slight majority of doses administered (52.9%; 99% CI, 21.9%–82.4%) was in the accepted range and for which the median dose given was of acceptable (7.6 mg/kg). Subaccepted dosing was particularly prevalent with codeine, as 76.7% (99% CI, 67.6%–84.4%) were moderately subaccepted and only 17.0% (99% CI, 10.4%–25.5%) of doses were in the accepted range.

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Reasons for Not Administering Analgesia

Of the caregivers who provided reasons for not administering analgesia over the first 3 postoperative days, 63% (99% CI, 38.4%–82.8%) indicated that their child was not in pain, 19% (99% CI, 5.1%–41.9%) indicated that their child refused to take medication, and the remainder (19%; 99% CI, 5.1%–41.9%) selected “other” reasons or declined to answer.

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DISCUSSION

Under the conditions of this study, we found that many of the participating low-income children of Hispanic origin experienced significant pain in the week after outpatient T&A surgery and received suboptimal pain management in the home setting. These findings are consistent with a previous study examining postoperative pain management in a non-Hispanic Caucasian population of children undergoing T&A.3

Around-the-clock analgesic therapy is the current American Society of Anesthesiologists recommended practice for postoperative pain management and prevention.2 In the home setting, accepted treatment can be achieved through maintenance of a regular analgesia dosing schedule, typically 1 dose every 4 to 6 hours.2,24 Accordingly, dosing every 4 to 6 hours should result in 12 to 18 total doses of analgesia in the first 3 postoperative days alone. Despite parents being told to follow package instructions of administering medication every 4 to 6 hours, we found that parents in this sample administered only 7 (3–9) total doses over the entire first 3 postoperative days. Parents often believe that it is best to give as little medication as possible to avoid risks and side effects.14 As such, they may choose to wait until their child is experiencing significant pain before administering analgesia. Unfortunately, this practice subjects the child to unnecessary discomfort in the time leading to the parent perceiving the pain and administering treatment and in the time it takes for the drug to become efficacious. Less than half of the doses administered by parents in this study were of accepted value. Given the lack of evidence supporting the efficacy of subaccepted dosing,24 it is unclear whether the few doses provided by parents actually provided symptom relief.

Cultural barriers may contribute to the suboptimal pain management practices seen in this study. The majority of the participants in the present study were strongly oriented toward traditional Hispanic culture, were first-generation Americans, and selected Spanish as their preferred language. Hispanic culture may be associated with increased stoicism and subsequent inhibition of behaviors that may burden others.10 The cultural emphasis on stoicism may contribute to decreased expression of pain by children and subsequent lower pain scores and medication dosing relative to their non-Hispanic Caucasian counterparts. This is of particular relevance in this study, given that pain intensity was assessed by child self-report. A prior study by our group found that child temperament and emotionality played a role in how children expressed pain after surgery and was subsequently predictive of parental analgesic administration.25 Although not directly assessed in this study, it is likely that such cultural factors as stoicism play a role in the development of child temperament and emotionality and in the manner in which they report pain. A greater understanding of the relationship between cultural norms and pain assessment would aid providers in delivering culturally sensitive care for Hispanic children and improving the translation of care guidelines to the home setting.

In addition, factors related to health systems may pose further barriers to adequate pain management after surgery. For example, inadequate health literacy and numeracy is common among Hispanic families of lower acculturation in the United States26 and profoundly impacts the ability to understand discharge instructions, medication administration, and symptomatology.27,28 A study by Ciampa et al.27 found that low acculturation among Hispanic caretakers is independently correlated with a decreased ability to perform child health care tasks, such as dosing liquid medication. Therefore, both acculturation and low literacy can impact the translation of pain management instructions to the home setting. Other factors that can impact pain management include such systemic issues as access to care and lack of insurance. In the context of postoperative pain management, these factors can limit the parents’ ability to pay for and obtain medication. Hispanic families of lower SES have been shown to experience more such health care systems barriers than their non-Hispanic Caucasian counterparts.4 Both providers and researchers would benefit from a greater understanding of the impact of such health system barriers on care for this vulnerable population.

This study has several methodological limitations that should be noted. First, because parents received pain assessment and analgesia surveys at discharge, they may have been increasingly alerted to behaviors associated with pain and been more conscious of treating pain. Second, the data used to assess analgesic dosing and pain scores were collected by parent report, and thus subject to reporting and collecting (i.e., coaching) bias. However, because of evidence suggesting that Hispanic patients may underreport pain, the occurrence of suboptimal pain management may be more profound than what was seen in this investigation.10 It is important to note that the purpose of this study was solely to focus on the management of postoperative pain in children of Hispanic origin and as such the study did not enroll a control group of non-Hispanic children. Such a study could be performed in the future. Last, our study focused exclusively on pain management in children undergoing T&A. Because this procedure can be associated with postoperative dysphagia, some children may be unwilling to consume oral analgesics. Hence, the analgesic patterns identified in this study may differ from those of other procedures.

We conclude that Hispanic children of lower SES experienced significant pain after outpatient surgery and were inadequately treated with analgesic therapy in the home setting. These findings lend evidentiary support to the need for further investigation into attitudinal- and systems-based barriers to postoperative pain management in this population. We anticipate that such findings will aid in the development of culturally and demographically sensitive interventions that will aid in the translation of clinical practice guidelines to the home setting. Such efforts are vital for achieving critical reductions in pediatric pain disparities.

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DISCLOSURES

Name: Rebecca Brown, BS.

Contribution: This author performed the initial analyses, drafted the initial manuscript, and revised the manuscript.

Attestation: Rebecca Brown approved the final manuscript as submitted and attests to the integrity of the original data and the analysis reported in this manuscript.

Name: Michelle A. Fortier, PhD.

Contribution: This author conceptualized and designed the study and reviewed and revised the manuscript.

Attestation: Michelle A. Fortier approved the final manuscript as submitted and attests to the integrity of the original data and the analysis reported in this manuscript. Dr. Fortier is the archival author.

Name: Sheeva Zolghadr, BS.

Contribution: This author performed the initial analyses.

Attestation: Sheeva Zolghadr approved the final manuscript as submitted.

Name: Padma Gulur, MD.

Contribution: This author contributed to revisions of the manuscript.

Attestation: Padma Gulur approved the final manuscript as submitted.

Name: Brooke N. Jenkins, MS.

Contribution: This author contributed to revisions of the manuscript.

Attestation: Brooke N. Jenkins approved the final manuscript as submitted.

Name: Zeev N. Kain, MD, MBA.

Contribution: This author conceptualized and designed the study, reviewed and revised the manuscript, and approved the final manuscript as submitted.

Attestation: Zeev N. Kain approved the final manuscript as submitted and attests to the integrity of the original data and the analysis reported in this manuscript.

This manuscript was handled by: James A. DiNardo, MD.

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