Premature Infant Pain Profile: development and initial validation

Systematic evaluation of pain in neonates: effect on the number of intravenous analgesics prescribed

OBJECTIVE

To document the effect of systematic evaluation of pain in neonates on prescription of intravenous analgesics in a level-III neonatal intensive care unit (NICU) as a marker of increased awareness of treating and preventing pain.

METHODS

Retrospective analysis of the number of yearly prescribed vials of intravenous analgesics in a level-III NICU during a period before (1996-1999) and after (2000 to August 2002) introduction of a multidimensional pain scale. Correction was carried out by multiple regression analysis for clinical co-variables (admissions, days on parenteral nutrition, days on respiratory support, surgical procedures), which also might explain changes in prescription of analgesics. Postoperative length (hours) of administration of analgesics was calculated in a group of infants (1996-2001) who all received cryotherapy for threshold retinopathy of prematurity (ROP) before (1996-1999) and since (2000-2001) introduction of pain evaluation.

RESULTS

The number of yearly prescribed vials increased from 3140+/-619 (mean+/-SD) to 5915+/-675 ( P<0.005). There is also a significant increase in the number of surgical interventions ( P<0.05) but not in days on respiratory support, days on parenteral nutrition or in number of admissions. After correction for the number of surgical procedures, the increase in prescribed vials remained significant ( P<0.05). In infants who received cryotherapy, a significant increase in length of postoperative analgesia (65-107 h, P<0.01) was documented. Even after correction for the increased postoperative length of ventilation, duration of postoperative analgesia remained significantly ( P<0.05) longer.

CONCLUSIONS

Systematic evaluation of pain increased awareness of treating and preventing pain in neonates, even after correction for clinical co-variables. This increase was not associated with an increase in potential side-effects (length of respiratory support, length of parenteral nutrition).

Are there developmentally distinct motor indicators of pain in preterm infants?

The aims of this study were to examine preterm infant reactions to pain in detail over prolonged time periods using multiple measures, and to assess the value of including specific body movements of the Neonatal Individualized Developmental Care and Assessment Program (NIDCAP) system to evaluate pain. Ten preterm infants born at 31 weeks mean gestational age (GA) and mean birth weight 1676 g were studied during a routine blood collection in a Level III neonatal intensive care unit (NICU). At 32-week post-conceptional age, computerized physiologic and video recordings were obtained continuously for 60 min (prior to, during and after lance). Motor and facial behaviors were coded independently, using the NIDCAP and the NFCS (Neonatal Facial Coding System), respectively, and compared with heart rate (HR) and oxygen saturation responses. Of the movements hypothesized to be stress cues in the NIDCAP model, extension of arms and legs (80%) and finger splay (70%) were the most common following lance. Contrary to the model, most infants (70%) had lower incidence of twitches and startles post-lance compared to baseline. Whereas all infants showed some NFCS response to lance, for three infants, the magnitude was low. HR increased and oxygen saturation decreased post-lance. Infants with more prior pain exposure, lower Apgar, and lower GA at birth, displayed more motor stress cues but less facial activity post-lance. Extension of extremities and finger splay, but not twitches and startles, from the NIDCAP, appear to be stress cues and show promise as clinical pain indicators to supplement facial and physiological pain measures in preterm infants.

Oral sucrose and pain relief for preterm infants

The frequency of painful procedures performed on preterm infants in the neonatal intensive care unit (NICU) presents a challenge to nurses who are attempting to provide effective pain relief, and to the infants themselves who may suffer adverse consequences in response to repeated painful procedures. One new pain relief intervention under study is the administration of oral sucrose, which may activate endogenous opioid systems within the body. Studies with preterm infants that have examined the use of oral sucrose as an analgesic during heelsticks and venipunctures have shown that sucrose is effective in reducing pain. Sucrose may also be combined with nonnutritive sucking to provide significant pain relief. The use of oral sucrose is now recommended with a wide range of painful procedures in the NICU. Promising results have been observed in studies with both term and preterm infants, but less research has occurred with preterm infants. Additional research is warranted to determine the most effective approaches for the administration of sucrose, to examine the effectiveness of sucrose with additional types of painful procedures, and to examine the effects of long-term repeated use of sucrose.

Assessment and management of acute pain in high-risk neonates

Neonates in the neonatal intensive care unit experience hundreds of painful procedures at a time of rapid neurological development. Although the immediate responses to pain may be protective, the potential long-term effects of early and under-treated pain are concerning. As pain assessment is the first step in the provision of appropriate and timely pain management, attention should be directed to the quantification of pain in terms of its location, severity, intensity and duration. Over the past decade, numerous pain measures have been developed for preterm and term neonates, however, most of them have been developed for research purposes and have not been tested in the clinical setting. In order to effectively implement pain measures in the clinical setting, the psychometric properties of reliability, validity, feasibility and clinical utility must be established. This review paper will highlight the importance of neonatal pain assessment and examine the psychometric properties of various measures of neonatal pain. Pharmacological and non-pharmacological interventions to manage acute pain in high-risk neonates will be addressed and future research topics will be proposed.

Reliability of two behavioral tools to assess pain in preterm neonates

CONTEXT

One of the main difficulties in adequately treating the pain of neonatal patients is the scarcity of validated pain evaluation methods for this population.

OBJECTIVE

To analyze the reliability of two behavioral pain scales in neonates.

TYPE OF STUDY

Cross-sectional.

SETTING

University hospital neonatal intensive care unit.

PARTICIPANTS

22 preterm neonates were studied, with gestational age of 34 +/- 2 weeks, birth weight of 1804 +/- 584 g, 68% female, 30 +/- 12 hours of life, and 30% intubated.

PROCEDURES

Two neonatologists (A and B) observed the patients at the bedside and on video films for 10 minutes. The Neonatal Facial Coding System and the Clinical Scoring System were scored at 1, 5, and 10 minutes. The final score was the median of the three values for each observer and scale. A and B were blinded to each other. Video assessments were made three months after bedside evaluations.

MAIN MEASUREMENTS

End scores were compared between the observers using the intraclass correlation coefficient and bias analysis (paired t test and signal test).

RESULTS

For the Neonatal Facial Coding System, at the bedside and on video, A and B showed a significant correlation of scores (intraclass correlation score: 0.62), without bias between them (t test and signal test: p > 0.05). For the Clinical Scoring System bedside assessment, A and B showed correlation of scores (intraclass correlation score: 0.55), but bias was also detected between them: A scored on average two points higher than B (paired t test and signal test: p < 0.05). For the Clinical Scoring System video assessment, A and B did not show correlation of scores (intraclass correlation score: 0.25), and bias was also detected between them (paired t-test and signal test: p < 0.05).

CONCLUSION

The results strengthen the reliability of the Neonatal Facial Coding System for bedside pain assessment in preterm neonates.

The fifth vital sign: implementation of the Neonatal Infant Pain Scale

Several psychometric tools are available to assess pain in the neonate. Although clinically tested, most of these tools have not been integrated into the assessment of the well newborn. Information is lacking regarding the implementation of such tools and their effects in clinical practice. The Neonatal Infant Pain Scale provides a measure of the intensity of an infant's response to pain. This article describes a hospital's implementation of the Neonatal Infant Pain Scale, including the education provided to nurses and utilization of the tool in the assessment of well newborns.

Ethological methods to develop nursing knowledge

Researchers from various fields use ethological methods to systematically observe, describe, and measure animal and human nonverbal behavior. The purpose of this article is to argue that their application in nursing will benefit development of descriptive-level knowledge about complex behavioral phenomena. To advance the argument for applying these methods in nursing, we examine the compatibility of the philosophical assumptions underlying ethology with nursing, assess if ethology can help nursing achieve some of its aims, and determine the benefits of using ethology when observation of a phenomenon is required. Neonatal pain is used to illustrate how ethology can be used to develop descriptive-level nursing knowledge and midrange theory.

Analgesic effect of breast feeding in term neonates: randomised controlled trial

OBJECTIVES

To investigate whether breast feeding is effective for pain relief during venepuncture in term neonates and compare any effect with that of oral glucose combined with a pacifier.

DESIGN

Randomised controlled trial.

PARTICIPANTS

180 term newborn infants undergoing venepuncture; 45 in each group.

INTERVENTIONS

During venepuncture infants were either breast fed (group 1), held in their mother's arms without breast feeding (group 2), given 1 ml of sterile water as placebo (group 3), or given 1 ml of 30% glucose followed by pacifier (group 4). Video recordings of the procedure were assessed by two observers blinded to the purpose of the study.

MAIN OUTCOME MEASURES

Pain related behaviours evaluated with two acute pain rating scales: the Douleur Aiguë Nouveau-né scale (range 0 to 10) and the premature infant pain profile scale (range 0 to 18).

RESULTS

Median pain scores (interquartile range) for breast feeding, held in mother's arms, placebo, and 30% glucose plus pacifier groups were 1 (0-3), 10 (8.5-10), 10 (7.5-10), and 3 (0-5) with the Douleur Aiguë Nouveau-né scale and 4.5 (2.25-8), 13 (10.5-15), 12 (9-13), and 4 (1-6) with the premature infant pain profile scale. Analysis of variance showed significantly different median pain scores (P<0.0001) among the groups. There were significant reductions in both scores for the breast feeding and glucose plus pacifier groups compared with the other two groups (P<0.0001, two tailed Mann-Whitney U tests between groups). The difference in Douleur Aiguë Nouveau-né scores between breast feeding and glucose plus pacifier groups was not significant (P=0.16).

CONCLUSIONS

Breast feeding effectively reduces response to pain during minor invasive procedure in term neonates.

Intravenous midazolam infusion for sedation of infants in the neonatal intensive care unit

BACKGROUND

The need for sedation for neonates undergoing uncomfortable procedures in the neonatal intensive care unit (NICU) has often been overlooked. Proper sedation may reduce stress and avoid complications during procedures such as mechanical ventilation. Midazolam is a short acting benzodiazepine that has been increasingly used in the NICU. However, the effectiveness of intravenous midazolam as a sedative in neonates has not been systematically evaluated.

OBJECTIVES

To determine whether intravenous midazolam infusion is an effective sedative, as evaluated by behavioural and/or physiologic measurements, for critically ill neonates undergoing intensive care, and to assess clinically significant short and long term adverse effects associated with its use.

SEARCH STRATEGY

Literature search according to the Cochrane Neonatal Review Group search strategy. Randomized and quasi-randomized controlled trials of intravenous midazolam use in neonates were identified by searching the Cochrane Controlled Trials Register (The Cochrane Library, Issue 3, 2002), MEDLINE (1985-2002), EMBASE (1980-2002), reference lists of published studies, personal files, and abstracts published in Pediatric Research from 1990-2002.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials of intravenous midazolam infusion in infants </= 28 days of age for sedation during mechanical ventilation or radiologic investigations were selected for review. Studies on midazolam use as an anesthetic or an anticonvulsant were excluded. Studies involving neonates and older infants and children were excluded if data for neonates could not be extracted.

DATA COLLECTION AND ANALYSIS

Data regarding the primary outcome of level of sedation (as evaluated by behavioural scales or physiologic parameters) were abstracted. Secondary outcomes including intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), death within 28 days of age, adverse effects associated with midazolam (hemodynamic and neurologic), days of ventilation, days of supplemental oxygen use, pneumothorax, length of NICU stay, and long term neurodevelopmental outcome were assessed. When appropriate, meta-analyses were performed using relative risk (RR), risk difference (RD), along with their 95% confidence intervals (95% CI) for categorical variables and weighted mean difference (WMD) for continuous variables.

MAIN RESULTS

Three trials were eligible for inclusion in the review. Data on level of sedation from the three trials could not be combined for meta-analysis because of differences in tools used to measure sedation levels. Two studies (Jacqz-Aigrain 1994, Arya 2001) showed a statistically significantly higher level of sedation in the midazolam group compared to the placebo group. The third study (Anand 1999) comparing midazolam to morphine and placebo found no statistically significant difference in sedation level among the three groups, but a statistically significantly higher level of sedation was found in the midazolam group compared with the placebo group during the treatment infusion. However, since the sedation scales used in all three studies have not been validated in preterm infants, the effectiveness of midazolam as a sedative in this population could not be ascertained. In the study by Jacqz-Aigrain et al (Jacqz-Aigrain 1994), blood pressure was statistically significantly lower in the midazolam group than in the placebo group on days one and two, although there was no statistically significant difference in the incidence of hypotension requiring albumin or vasoactive drugs between groups. The study by Anand et al (Anand 1999) showed a statistically significant higher incidence of adverse neurologic events (death, grade III-IV IVH, PVL) in the midazolam group compared with the other groups. In addition, meta-analysis of available data from two studies (Jacqz-Aigrain 1994, Anand 1999) showed a statistically significantly longer duration of NICU stay in the midazolam group compared to the placebo group (WMD 5.4 days, 95%CI 0.4, 10.5). Meta-analyses of other secondary outcomes showed no statistically significant differences between the midazolam and placebo groups.

REVIEWER'S CONCLUSIONS

There are insufficient data to promote the use of intravenous midazolam infusion as a sedative for neonates undergoing intensive care. This review raises concerns about the safety of midazolam in neonates. Further research on the effectiveness and safety of midazolam in neonates is needed.

[The neonatal behavioral observation: a pertinent source of medical informations]

The neonatal behavioral observation is an important source of medical information in three domains: 1) assessment of development which can be done with the Assessment of Preterm Infant Behavior, 2) assessment of pain with the analysis of facial expression using validated pain scales such as the Neonatal Facial Coding System, 3) assessment of brain injuries with the Quality Assessment of General Movements. Such a behavioral observation of the newborn using validated tools is a useful complement of the neuro-imaging techniques.

Pain reduction at venipuncture in newborns: oral glucose compared with local anesthetic cream

OBJECTIVE

A number of studies have shown that orally administered sweet-tasting solutions reduce signs of pain during painful procedures. The local anesthetic cream EMLA has recently been shown to be safe for use in neonates. This study compared the pain-reducing effect of orally administered glucose with that of EMLA cream during venipuncture in newborns.

METHODS

Randomized, controlled, double-blind study including 201 newborns undergoing venipuncture for clinical purposes. Ninety-nine of the newborns received EMLA on the skin and orally administered placebo (sterile water), and 102 received glucose 30% orally and placebo (Unguentum Merck) on the skin. Symptoms associated with pain at venipuncture were measured with the Premature Infant Pain Profile (PIPP) scale (also validated for full-term infants). Heart rate and crying time were recorded.

RESULTS

There were no differences in background variables between the 2 groups. The results shows that the PIPP scores were significantly lower in the glucose group (mean: 4.6) compared with the EMLA group (mean: 5.7). The duration of crying in the first 3 minutes was significantly lower in the glucose group (median: 1 second) than in the EMLA group (median: 18 seconds). There were significantly fewer patients in the glucose group who were scored having pain (defined as PIPP score above 6); 19.3% compared with 41.7% in the EMLA group. The changes in heart rate were similar in both groups.

CONCLUSIONS

We found that glucose is effective in reducing symptoms associated with pain from venipuncture in newborns and seems to be better than the local anesthetic cream EMLA.

Efficacy and safety of sucrose for procedural pain relief in preterm and term neonates

BACKGROUND

Preterm and acutely ill term neonates who are hospitalized in a neonatal intensive care unit are subjected to multiple frequent invasive and painful procedures aimed at improving their outcome. Although several trials to determine the efficacy of sucrose for managing procedural pain in preterm and acutely ill term neonates have been developed, these have generally lacked methodological rigor and have not provided clinicians with clear practice guidelines.

OBJECTIVES

To compare the efficacy and safety of three interventions for relieving procedural pain associated with heel lances in preterm and term neonates, and to explore the influence of contextual factors including sex, severity of illness, and prior painful procedures on pain responses.

METHODS

In a randomized controlled trial, 190 neonates were stratified by gestational age and then randomized to receive (a) sucrose and nonnutritive sucking (n = 64), (b) sucrose alone (n = 62), or (c) sterile water and nonnutritive sucking (control) (n = 64) to evaluate the efficacy (pain response as measured using the Premature Infant Pain Profile) (Stevens, Johnson, Petryshen, & Taddio, 1996) and safety (adverse events) following a scheduled heel lance during the first week of life. Stratification was used to control for the effects of age on pain response.

RESULTS

Significant differences in pain response existed among treatment groups (F = 22.49, p <.001), with the lowest mean Premature Infant Pain Profile scores in the sucrose and nonnutritive sucking group. Efficacy of sucrose following a heel lance was not affected by severity of illness, postnatal age, or number of painful procedures. Intervention group and sex explained 12% of the variance in Premature Infant Pain Profile scores. Few adverse events occurred (n = 6), and none of them required medical or nursing interventions.

CONCLUSIONS

The combination of sucrose and nonnutritive sucking is the most efficacious intervention for single heel lances. Research on the effects of gestational age on the efficacy and safety of repeated doses of sucrose is required.

Challenges of judging pain in vulnerable infants

The inevitability of pain during infancy and its potential for destructive impact impose a burden on caregiving adults. An armamentarium of effective pharmacological, behavioral and environmental interventions is available if pain were recognized and accurately assessed. Infants have limited behavioral repertoires that make identification of specific needs difficult, mothers and other caregivers prone to high levels of protection and redundant care. But more specific care can best suit infant requirements. Certain behaviors are sensitive to states of distress, including pain, for example, cry and disruption of usual activities such as sleep. Others appear more specific, for example, facial activity. This paper proposes that effective care is best delivered to infants and children if we recognize the complexities of the sociocommunication process; subjective states are encoded in behavioral activity and caregivers must be able to recognize the meaning of these actions. The paper delineates some features of the process whereby caregivers arrive at judgments of infant's needs and make decisions concerning interventions.

Clinical utility and clinical significance in the assessment and management of pain in vulnerable infants

Pain in vulnerable populations unable to provide verbal report is challenging in terms of measurement and treatment. Clinicians strive to provide the best possible pain management for infants in the NICU, yet they are often hindered due to paucity of measures that are not only reliable and valid but also clinically useful. Clinical utility of measures is difficult to establish due to a lack of consistent definition of the construct, varied methods of determination, and the secondary importance afforded to this issue in relation to the establishment of reliability and utility. Without clinically useful pain measures, however, clinicians are unable and unlikely to assess the infant's pain or the effectiveness of pain-relieving interventions. Furthermore, even when the clinician is able to assess pain using a valid measure with a minimum of time, cost, and instruction, the clinical significance of any reduction in pain scores needs to be interpreted in terms of the infant and his/her care provider. The issue of defining the extent of change in pain scores that is clinically significant or important remains unclear. Clarity will involve assigning meaning to particular changes in pain scores for vulnerable infants across a broad array of situations and severities of pain. Although research on this topic in children and adults provides some guidance to this dilemma, only through innovative and creative methods will we be able to address these issues.

Are postoperative pain instruments useful for specific groups of vulnerable infants?

Based on the authors' review of the literature on pediatric postoperative pain assessment with special attention to groups of vulnerable infants, this article (1) reports on type of surgery and its relationship to postoperative pain intensity; (2) reviews the characteristics of existing postoperative pain instruments for neonates, infants, and toddlers; (3) discusses timing, duration, and who should assess postoperative pain; (4) reviews the specific literature on pain assessment in critically ill infants, including the extremely low birth weight and the cognitively and/or neurologically impaired infant, and (5) discusses the role of parents in postoperative pain assessment. Postoperative pain instruments are useful for specific groups of vulnerable infants, but it is important that in addition to the valuable scoring of pain, common sense is used and factors such as developmental stage, temperament and personality, number of previous painful experiences, anxiety, and environmental factors are taken into account.

Bedside assessment of heel lance pain in the hospitalized infant

OBJECTIVE

To evaluate a method of pain assessment to be used for hospitalized infants requiring blood test by a heel lance procedure.

DESIGN

Observational study evaluating pain measurement and interrater reliability of pain measurement in hospitalized infants.

SETTING

A Level III neonatal unit and a cardiac surgical unit at a major pediatric teaching hospital.

PARTICIPANTS

20 infants whose gestational age ranged from 28 weeks to full-term.

MAIN OUTCOME MEASURES

Observations included behavioral measurements (facial expressions, body movements, and crying characteristics) and the physiologic measure of heart rate. Interrater reliability and the feasibility of using the procedural pain assessment method at the bedside were considered.

RESULTS

The three behavioral measurements and heart rate were responsive to the heel lance. Interrater reliability was high for facial expressions and crying scores but was low for body movements.

CONCLUSIONS

Modifications have been made to the method of procedural pain assessment to be used in a subsequent study. The modified method is expected to be a reliable measure of procedural pain caused by a heel lance and can easily be used at the bedside during the course of further research.

Assessment and management of pain and distress in the neonate

Pain management is an integral focus of neonatal care. This article reviews the physiology and impact of neonatal pain and distress and pain assessment tools, as well as clinical interventions and current controversies in the management of pain and distress in neonates. Current guidelines to enhance the recognition and treatment of pain are highlighted.

Creation of a neonatal end-of-life palliative care protocol

OBJECTIVE

To create a protocol delineating the needs of patients, families, and staff necessary to provide a pain-free, dignified, family-, and staff-supported death for newborns who cannot benefit from intensive, life-extending, technological support.

STUDY DESIGN

Using Internet e-mail, a Delphi study with sequential questionnaires soliciting participant response, investigator analysis, and follow-up responses from participants was conducted to build a consensus document. Institutional review was granted and respondents gave consent. Recruitment was conducted at medical, ethics, nursing, and multidisciplinary organization meetings. Synthesis of 16 palliative care/end-of-life protocols developed by regional, institutional, and parent organizations was included. Participants from 93 locations in the US and 4 abroad gave feedback to 13 questions derived from clinical experience and the literature. The data underwent four rounds of analysis with 95% retention of the 101 participants over an 18-month period.

RESULTS/CONCLUSION

Specific consensus-based recommendations are presented with a description of palliative care; categories of candidates; planning and education needed to begin palliative care services; relationships between community and tertiary centers; components of optimally supported neonatal death; family care, including cultural, spiritual, and practical needs; ventilator withdrawal, including pain and symptom management; recommendations when death does not occur after cessation of life-extending interventions; family follow-up care; and necessary ongoing staff support.

Efficacy of sucrose as analgesia for procedural pain in neonates

BACKGROUND

Most infants experience painful procedures during their first days. Minimization of pain to decrease noxious effects is warranted. This Critically Appraised Topic (CAT) evaluates a meta-analysis of 5 randomized controlled trials (RCTs) that examined sucrose as analgesia for neonatal procedural pain.

PURPOSE

To determine the efficacy and optimal dosing of sucrose for neonatal procedural pain.

METHODS

A literature search identified 5 studies that met criteria for inclusion in the meta-analysis, for a total of 271 infants studied. The primary outcome measure was crying time, measured for 3 minutes after a painful procedure following administration of water or varying doses of sucrose.

RESULTS

There was no difference in crying time between the 0.18 g sucrose and water groups (P > 0.05), but crying time was significantly less in the other sucrose groups. Doses of at least 0.24 g (2 mL 12% sucrose) were found to be most effective. No adverse effects were reported.

CONCLUSION

This CAT systematically appraises this meta-analysis, provides clinical bottom lines, and includes recommendations for practice.

Treatment of pain in acutely burned children

The child with burns suffers severe pain at the time of the burn and during subsequent treatment and rehabilitation. Pain has adverse physiological and emotional effects, and research suggests that pain management is an important factor in better outcomes. There is increasing understanding of the private experience of pain, and how children benefit from honest preparation for procedures. Developmentally appropriate and culturally sensitive pain assessment, pain relief, and reevaluation have improved, becoming essential in treatment. Pharmacological treatment is primary, strengthened by new concepts from neurobiology, clinical science, and the introduction of more effective drugs with fewer adverse side effects and less toxicity. Empirical evaluation of various hypnotic, cognitive, behavioral, and sensory treatment methods is advancing. Multidisciplinary assessment helps to integrate psychological and pharmacological pain-relieving interventions to reduce emotional and mental stress, and family stress as well. Optimal care encourages burn teams to integrate pain guidelines into protocols and critical pathways for improved care.

An evaluation of the effects of sucrose on neonatal pain with 2 commonly used circumcision methods

OBJECTIVE

The purpose of this study was to identify the least painful circumcision method.

STUDY DESIGN

The infants were circumcised with either the Mogen or the Gomco procedure and were given a sweetened pacifier or a pacifier dipped in water. All infants had a eutectic mixture of local anesthetic cream applied before circumcision. The duration of the crying and grimacing were measured.

RESULTS

The Gomco procedure took 1.9 times longer to complete. Infants who were circumcised with the Mogen procedure cried and grimaced far less than infants who were circumcised with the Gomco procedure (P =.0001). Sucrose on a pacifier was far more analgesic than water on a pacifier for infants in the Gomco group.

CONCLUSION

On the basis of these and other findings on pain prevention and amelioration, we recommend that a local anesthetic be administered in advance of circumcision and that the Mogen procedure be used, unless contraindicated. We also recommend that infants be given a sweetened pacifier before, during, and after circumcision if the Gomco method is used.

Assessment and management of pain in neonates

Neonates are capable of experiencing pain from birth onwards. An impressive body of neuroanatomical, neurochemical and biobehavioural evidence, which has accumulated over the past 2 decades, supports this capability. This evidence mandates health professionals to attend to the prevention, elimination, or at the very least, control of pain for infants. This mandate is essential since pain is known to have both immediate and long term effects, especially if pain is untreated and is severe, prolonged or frequently experienced. Therefore, pain must be assessed frequently, not only to measure location, intensity and duration but also to determine the effectiveness of interventions implemented to control pain. An impressive array of measures for assessing acute pain in infants exists which incorporates valid pain indicators in this population. However, there is a need to develop new measures to assess chronic pain conditions and pain in infants in acute situations.

Relations between behavioral and cardiac autonomic reactivity to acute pain in preterm neonates

OBJECTIVE

The purpose of this study was to assess relations and concordance between behavioral and physiologic reactivity to pain in preterm neonates at 32 weeks postconceptional age as a function of gestational age at birth.

SETTING

Level III neonatal intensive care unit.

DESIGN/PATIENTS

The study group comprised 136 preterm neonates (mean [range] birthweight, 1,020 g [445-1,500 g]: gestational age at birth, 28 weeks [23-32 weeks]) separated into three groups according to gestational age at birth as follows: 23 to 26 weeks (n = 48), 27 to 29 weeks (n = 52), and 30 to 32 weeks (n = 36).

OUTCOME MEASURES

Reactivity to routine blood collection at 32 weeks postconceptional age was assessed using bedside-recorded behavioral and autonomic measures. Coders who were blinded to the study design scored behavioral responses (facial activity using the Neonatal Facial Coding System, sleep/waking state, and finger splay). Autonomic reactivity was assessed by change in heart rate and spectral analysis of heart rate variability (change in low-frequency and high-frequency power, and the ratio of low-frequency to high-frequency power during blood collection).

RESULTS

Facial activity and state correlated moderately with change in heart rate across gestational age groups (r = 0.41-0.62). Facial activity and state did not correlate significantly with change in low-frequency and high-frequency power, or the ratio of low-frequency to high-frequency power (r = 0.00-0.31). Finger splay did not correlate with any autonomic recording (r = 0.03-0.41). Concordance between established biobehavioral measures of pain revealed individual differences. Although some neonates showed high behavioral but low physiologic reactivity, other neonates displayed the opposite reaction; however, the majority displayed concordant reactions.

CONCLUSIONS

The study findings confirm the value of measuring domains independently, especially in neonates born at a very young gestational age.

Development and initial validation of the EDIN scale, a new tool for assessing prolonged pain in preterm infants

OBJECTIVE

To develop and validate a scale suitable for use in clinical practice as a tool for assessing prolonged pain in premature infants.

METHODS

Pain indicators identified by observation of preterm infants and selected by a panel of experts were used to develop the EDIN scale (Echelle Douleur Inconfort Nouveau-Né, neonatal pain and discomfort scale). A cohort of preterm infants was studied prospectively to determine construct validity, inter-rater reliability, and internal consistency of the scale.

RESULTS

The EDIN scale uses five behavioural indicators of prolonged pain: facial activity, body movements, quality of sleep, quality of contact with nurses, and consolability. The validation study included 76 preterm infants with a mean gestational age of 31.5 weeks. Inter-rater reliability was acceptable, with a kappa coefficient range of 0.59-0.74. Internal consistency was high: Cronbach's alpha coefficients calculated after deleting each item ranged from 0.86 to 0.94. To establish construct validity, EDIN scores in two extreme situations (pain and no pain) were compared, and a significant difference was observed.

CONCLUSIONS

The validation data suggest that the EDIN is appropriate for assessing prolonged pain in preterm infants. Further studies are warranted to obtain further evidence of construct validity by comparing scores in less extreme situations.

The association between physiological and behavioral pain measures in 0- to 3-year-old infants after major surgery

To estimate the association between behavioral and physiological pain measures and to identify determinants predicting the level of association, the COMFORT 'behavior' scale, heart rate (HR), mean arterial pressure (MAP), and the variability of HR and MAP (HRV and MAPV) were assessed every 3 hours after major abdominal or thoracic surgery. Subjects were 204 infants aged 0-3 years. The within-subject correlations, using the repeated measures, were 0.37, 0.44, 0.48, and 0.49 for COMFORT 'behavior' with HRV, HR, MAP, and MAPV, respectively. Neonates had lower behavior-physiology correlations than the older infants, due to low pain scores. Pain characteristics significantly predicted the COMFORT 'behavior'-HR/MAP correlations, suggesting that the behavior-physiology correlations increase with increasing pain. The behavior-physiology correlations were not greatly affected by physical condition. These data demonstrate large interindividual differences in behavior-physiology correlations after major surgery in 0- to 3-year-old infants. These differences should be further explored in future research.

Sensorial saturation: an effective analgesic tool for heel-prick in preterm infants: a prospective randomized trial

Pain is traumatic for preterm infants and can damage their CNS. We wanted to assess whether multisensorial stimulation can be analgesic and whether this effect is only due to oral glucose or sucking. We performed a randomized prospective study, using a validated acute pain rating scale to assess pain during heel-prick combined with five different procedures: (A) control, (B) 10% oral glucose plus sucking, (C) sensorial saturation (SS), (D) oral water, and (E) 10% oral glucose. SS is a multisensorial stimulation consisting of delicate tactile, vestibular, gustative, olfactory, auditory and visual stimuli. Controls did not receive any analgesia. We studied 85 heel-pricks (5 per baby) performed for routine blood samples in 17 preterm infants (28-35 weeks of gestational age). We applied in random order in each patient the five procedures described above and scored pain. SS and sucking plus oral glucose have the greater analgesic effect with respect to no intervention (p < 0.001). The effect of SS is statistically better than that of glucose plus sucking (p < 0.01). SS promotes interaction between nurse and infant and is a simple effective form of analgesia for the NICU.

Infant behaviors as indicators of established acute pain

ISSUES AND PURPOSE

Many infant pain assessment tools use infant behaviors indicative of increased arousal. These tools were developed and tested using clinical situations involving acute immediate pain responses. Are these behaviors valid, clinical indicators of acute established pain (non-procedurally caused) pain? Can these tools be used to assess acute established infant pain? This article explores research findings to answer these questions.

CONCLUSIONS

Findings suggest that behaviors indicative of increased arousal (e.g., crying, facial expressions that accompany crying) are nonspecific indicators of distress rather than independent indicators of established acute pain. Thus, the use of behaviors representing acute immediate pain responses to assess acute established pain, or the use of tools that incorporate these behaviors, can be misleading.

PRACTICE IMPLICATIONS

Always use acute immediate pain behavioral responses (behaviors indicative of increased arousal) in conjunction with clinical data concerning "likelihood of pain" and consolability.

Sucrose analgesia for minor procedures in newborn infants

OBJECTIVE

To evaluate the role of intraoral sucrose and other sweet-tasting solutions for the management of pain associated with minor procedures in newborns.

DATA SOURCES

A search of MEDLINE articles from 1966 to August 1999 and an extensive review of journals was conducted. MeSH headings included analgesia, sucrose, and neonate.

DATA SYNTHESIS

Newborn infants regularly undergo minor invasive procedures for which analgesics are not routinely used. Intraoral sucrose and other sweet-tasting solutions appear to diminish surrogate biomarkers of pain response as evidenced by a reduction in crying time, smaller increases in heart rate, and lower pain scale ratings.

CONCLUSIONS

These studies appear to suggest that sucrose solution 0.5 g provides effective analgesia with no reported adverse effects.

Nursing judgment: the key to pain assessment in critically ill children

Pain assessment in critically ill children emphasizes the need to place expert nursing judgment prominently on the list of assessment strategies. The expert nurse is uniquely qualified to identify subtle responses to physiologic and environmental stimuli and to titrate analgesics and other pain relief strategies accordingly. While it is challenging to assess pain with limited verbal and behavioral cues, pain assessment is not only possible, but even more critical, when the available cues are subtle and can be easily overlooked or attributed to other causes. The question that sparked these comments reflects the passion I so often witness in intensive care nurses committed to eliminating pain as an emotional and physiological stressor for these vulnerable children. When that passion is empowered by evidence-based nursing judgment, children receive the best possible care.

Effects of rectally administered paracetamol on infants delivered by vacuum extraction

OBJECTIVE

To evaluate whether paracetamol (20 mg/kg rectally) relieves pain in infants delivered by vacuum extraction, and improves clinical condition.

METHODS

Prospective, randomised, double-blind, placebo-controlled study. Infants delivered by vacuum extraction were randomised either to the study group (n=61) and given paracetamol or to the control group (n=61) receiving placebo. Pain assessment was performed by a validated pain score and by scoring the clinical condition. Both scores and clinical symptoms in these groups were compared with symptoms in a reference group (n=66) with uncomplicated pregnancy and delivery in vertex position without vacuum extraction.

RESULTS

Pain score did not differ between groups; clinical condition in the study group improved only after the first dose. There was a significant difference (P<0.05) in objective clinical symptoms in the vacuum extraction groups, compared to the reference group.

CONCLUSION

One dose of paracetamol given to neonates delivered by vacuum extraction significantly improved their clinical condition, but did not result in a significant change in objective pain scores. Subsequent doses of paracetamol did not show any effect on the clinical symptoms or appearance of the neonates studied.

Fluctuations in established infant pain behaviors

This study compares behaviors that differed across levels of established (e.g., nonprocedural) infant pain with those that differed between periods of greater and lesser distress within any level of infant pain. Sixty-four videotaped infants of two ages (0 to 3 months and 7 to 12 months) and four levels of established infant pain (none, mild, moderate, and severe) were used. Pain was from medical or surgical causes. Behaviors were compared between the most distressed (HI) and the least distressed (LO) video segments per infant and across the four levels of infant pain using a two-level (distress and level of pain) MANOVA. Many behaviors were indicative of high levels of established pain and greater distress. Others increased with greater distress but lower levels of pain. Findings suggest that many behaviors indicative of high distress that constitute the immediate infant pain response are not good indicators of levels of established infant pain.

The premature infant and painful procedures

Pain management for premature infants raises challenging questions for nurses. This group of infants is often physiologically fragile and they may undergo frequent painful procedures on a daily basis. Contrary to ideas from the past, premature infants are able to feel pain, and nervous system elements required for the transmission of painful stimuli are functional by 24 weeks gestation. Painful procedures are harmful to the infant's physiological stability and the ability to self-regulate, which includes maintenance of motor control and stable sleep/wake cycles. Assessment of pain in the premature infant is complex. Major indicators of pain include facial grimaces and physiological parameters such as heart rate and oxygen saturation. The Premature Infant Pain Profile (PIPP) is one tool designed specifically for preterm infants. Nonpharmacological nursing measures such as swaddling or nesting and offering a pacifier are useful strategies to help infants cope with painful procedures. The nurse may also maintain a therapeutic environment to assist the infant in self-regulation. Pharmacological agents such as morphine, fentanyl, and acetaminophen are effective in relieving procedural pain. The use of oral sucrose before and during painful procedures offers new possibilities for pain relief. Recent research shows that oral sucrose is a safe and effective analgesic for short-term procedures. Research studies to determine the most effective doses and modes of oral sucrose administration are ongoing. It is thought that the relief of pain is owing to the sweet taste of the sucrose that activates endogenous pain-modulating systems.

Behavior, pain perception, and the extremely low-birth weight survivor

This article explores the literature concerning responses to pain of both premature and term-born newborn infants, the evidence for short-term and long-term effects of pain, and behavioral sequelae in individuals who have experienced repeated early pain in neonatal life as they mature. There is no doubt that pain causes stress in babies and this in turn may adversely affect long-term neurodevelopmental outcome. Although there are methods for assessing dimensions of acute reactivity to pain in an experimental setting, there are no very good measures available at the present time that can be used clinically. In the clinical setting repeated or chronic pain is more likely the norm rather than infrequent discrete noxious stimuli of the sort that can be readily studied. The wind-up phenomenon suggests that, exposed to a cascade of procedures as happens with clustering of care in the clinical setting in an attempt to provide periods of rest for stressed babies, an infant may in fact perceive procedures that are not normally viewed as noxious, as pain. Pain exposure during lifesaving intensive medical care of ELBW neonates may also affect subsequent reactivity to pain in the neonatal period, but behavioral differences are probably not likely to be clinically significant in the long term. Prolonged and repeated untreated pain in the newborn period, however, may produce a relatively permanent shift in basal autonomic arousal related to prior NICU pain experience, which may have long-term sequelae. In the long run, the most significant clinical effects of early pain exposure may be on neurodevelopment, contributing to later attention, learning, and behavior problems in these vulnerable children. Although there is considerable evidence to support a variety of adverse effects of early pain, there is less information about the long-term effects of opiates and benzodiazepines on the developing central nervous system. Current evidence reviewed suggests that judicious use of morphine for adjustment to mechanical ventilation may ameliorate the altered autonomic response. It may be very important, however, to distinguish stress from pain. Animal evidence suggests that the neonatal brain is affected differently when exposed to morphine administered in the absence of pain than in the presence of pain. Pain control may be important for many reasons but overuse of morphine or benzodiazepines may have undesirable long-term effects. This is a rapidly evolving area of knowledge of clear relevance to clinical management likely to affect long-term outcomes of high-risk children.

Pain assessment in infants and children

The science of pain assessment for infants and children has grown substantially in the past several decades to the point that valid and reliable methods for pain assessment are available for use in clinical settings. Accurate pain assessment requires consideration of children's developmental level, type of pain experienced, history and context of pain, family influences, and interaction with the health care team. Research is needed to improve the sensitivity, specificity, and generalizability of pain-assessment tools and to more fully incorporate contextual factors into the objective assessment process. Finally, the improvement of pain assessment in the clinical setting can be viewed as a patient care quality issue, and continuous quality improvement methods can be used effectively to incorporate pain assessment as an integral component of every infant's and child's health care.

Plasma norepinephrine levels, vagal tone index, and flexor reflex threshold in premature neonates receiving intravenous morphine during the postoperative period: a pilot study

OBJECTIVE

The goal of this study was to evaluate the effects of a single dose of intravenous morphine on postoperative pain in extremely premature neonates after thoracotomy.

DESIGN

Descriptive correlational study.

PATIENTS

Twenty-four critically ill mechanically ventilated premature neonates with a mean gestational age of 26.1 +/- 2.1 (SD) weeks and a postnatal age of 13.8 +/- 8.1 (SD) days.

OUTCOME MEASURES

Plasma norepinephrine (NE) levels, vagal tone index (VTI), and flexor reflex threshold were measured preoperatively, immediately before, and 20 and 60 minutes after the administration of the first postoperative dose of morphine (0.1 mg/kg).

RESULTS

One-way repeated-measures ANOVA revealed no significant change in plasma NE levels from baseline levels (df[2,32] = 2.40, p = 0.11). Pre- and postmorphine VTI values were significantly lower than preoperative values (df[3,60] = 6.04, p = 0.0012), but no significant differences were found between pre- and postmorphine VTI values. Neonates (n = 10) who had a flexor reflex response during the postoperative period demonstrated no significant differences in the force required to elicit a flexor reflex across the four measurements (df[3,27] = 0.76, p = 0.53); however, the flexor reflex responses were significantly less vigorous during the postoperative period than at baseline.

CONCLUSIONS

Findings from this pilot study suggest that the dose of morphine commonly used to treat postoperative pain in premature neonates does not affect NE, VTI, and flexor reflex threshold values within 1 hour of administration.

Need for a reliable pain evaluation scale in the newborn in Sweden

BACKGROUND

A major problem in pain treatment in the newborn is the ability to assess the degree of experienced pain. Several different methods for estimating pain in the newborn have been introduced in recent years. The objectives of this study were to see whether pain scoring was used in Swedish neonatal units, and by which method, and furthermore to observe whether any changes had occurred between 1993 and 1998.

METHOD

A questionnaire was distributed to all Swedish neonatal units in 1993 and 1998.

RESULTS

In both 1993 and 1998, 86% of all clinics answered the questionnaire. Two-thirds of these clinics used some method for estimating pain in the newborn at both times. Eight clinics used a structured method in the latter period compared to one in the earlier period. A higher proportion of units having full intensive care measured pain compared to other units.

CONCLUSION

The study shows that an unchanging low proportion of neonatal units in Sweden attempt to assess pain. There is a minor increase in the number of departments that use a structured method for pain scoring. Documentation of pain intensity is still inadequate and should be improved.

Are twitches, startles, and body movements pain indicators in extremely low birth weight infants?

OBJECTIVE

The goal of this study was to examine whether body activity such as postural, trunk, and limb movements may be potential pain cues in preterm infants.

DESIGN

Convenience sample.

SETTING

Level III neonatal intensive care unit (NICU).

PATIENTS

Extremely low birth weight (< or = 1,000 g) preterm infants (n = 64) undergoing routine NICU medical care.

OUTCOME MEASURES

Procedures likely to differ in evoking distress (i.e., endotracheal suctioning, chest physical therapy, diaper change, or nasogastric feed) were observed. Behaviors were recorded at bedside using the Neonatal Individualized Developmental Care and Assessment Program system.

RESULTS

Changes in heart rate and sleep/waking state were related to the procedures, supporting the assumption of differing relative disruption to the infant. Arching, squirming, startles, and twitching were not observed significantly more during procedures than at baseline. After controlling for background variables, finger splay and leg extension were significantly related to ongoing procedures. Facial brow raising was a function of the number of invasive procedures in the past 24 hours; thus, it may be a useful cue of sensitization.

CONCLUSIONS

Some extensor movements seemed to be distress signals, whereas tremors, startles, and twitches were not related to discomfort during the observation period. These behaviors may differ qualitatively during longer lasting tissue invasive events. The results of this study indicate the need for more in-depth study of patterns of motor activity in preterm infants over longer observation periods to evaluate potential signs of stress and pain in babies undergoing NICU medical care.

Differences in pain expression between male and female newborn infants

The study of neonatal gender differences in pain expression is important since neonatal pain behavior occurs prior to any learned reaction pattern. The objective of this study was to verify the presence of gender differences in pain expression in preterm and term newborn infants. Sixty-five consecutive neonates (37 female and 28 male infants) with gestational age between 28 and 42 weeks and with 25-120 h of life were studied. Healthy term neonates required a capillary puncture for PKU screening and clinically stable premature infants needed a capillary puncture for glucose dosage. The Neonatal Facial Coding System (NFCS) and the Neonatal Infant Pain Scale (NIPS) were evaluated at bedside prior to the puncture, when patients were at rest, during foot heating; during capillary puncture; and at 1, 3, and 5 min after heel lancing. Results were analyzed by repeated-measures ANOVA followed by the Multiple Comparison Method of Bonferroni. A significant difference among the mean NFCS scores during the six study periods was noted for the whole group of neonates (P<0.000001). Also, a significant interaction between the NFCS score profile in female and male neonates at the different study periods was observed (P=0.025). Regarding NIPS, ANOVA showed only a significant difference among the mean NIPS scores during the six study periods for the whole group of neonates (P<0.000001). No significant interactions between gestational age and time, nor between gestational age and gender were noted, for both NFCS and NIPS. In conclusion, recently born female neonates of all gestational ages expressed more facial features of pain than male infants, during the capillary puncture and 1 min afterwards. Maybe differences in pain processing and/or pain expression among genders may explain this finding.

Sucrose for analgesia in newborn infants undergoing painful procedures

BACKGROUND

Management of pain for neonates is less than optimal. The administration of sucrose with and without non-nutritive sucking (pacifiers) has been the most frequently studied non-pharmacological intervention for relief of procedural pain in neonates.

OBJECTIVES

To determine the efficacy, effect of dose, and safety of sucrose for relieving procedural pain as assessed by physiologic and/or behavioural indicators.

SEARCH STRATEGY

Standard methods as per the Neonatal Collaborative Review Group. A MEDLINE search was carried out for relevant randomized controlled trials (RCTs) published from January 1966 - November 1, 1997; EMBASE from 1993-1997; Reference Update search on November 11, 1997 and search of the Cochrane Library Issue 4 on November 11, 1997. Key words and (MeSH) terms included, infant/newborn, pain, analgesia and sucrose. Personal files, bibliographies, the most recent relevant neonatal and pain journals and conference proceedings were searched manually. Unpublished studies were not included. Language restrictions were not imposed.

SELECTION CRITERIA

RCTs in which term and/or preterm neonates undergoing heel lance, venepuncture or intramuscular injection (immunization) received sucrose or water/placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed according to the methods of the Neonatal Collaborative Review Group. Quality measures included; blinding of randomization, blinding of intervention, completeness of follow up and blinding of outcome measurement. Data were abstracted and independently checked for accuracy by the two investigators. The inconsistency in outcome measures and differences in the statistical reporting of results made meta-analysis impossible. We were not able to identify two studies in which the same physiologic and/or behavioral outcomes following a noxious stimulus (heel-lance, venepuncture, intramuscular injection) were measured and reported in an identical fashion using means and standard deviations (or standard errors). The results are therefore reported for each accepted study separately.

MAIN RESULTS

Fifteen studies were identified for possible inclusion in this systematic review. Five studies were excluded; three RCTs were excluded as in these trials the number of infants randomized to treatment vs. placebo groups were not reported; one study was not an RCT, and in one RCT the neonates did not undergo a painful procedure. Ten RCTs were included in this review. Sucrose in a wide range of dosages was generally found to decrease univariate physiologic (heart rate) and behavioural (the mean percent time crying, total cry duration, duration of first cry, and facial action) pain indicators and multivariate [Premature Infant Pain Profile (PIPP)] pain outcomes in neonates undergoing heelstick or venepuncture. An optimal dose of sucrose to reduce pain associated with procedures in preterm and term neonates could not be identified through this systematic review.

REVIEWER'S CONCLUSIONS

Sucrose reduces physiologic and/or behavioral indicators of stress/pain in neonates following procedural pain stimuli (heel lance, venepuncture, immunization). There was inconsistency in the dose of sucrose that was effective and an optimal dose to be used in preterm and/or term infants could not be identified. Considerations for future research are to describe the painful procedure and intervention in detail, to use appropriate sample size to show a statistically significant reduction in pain, to use a multidimensional conceptualization of pain, to select outcome measures that are reliable and valid pain indicators and to account for the variation in the infant's response and context in which the pain is experienced. The use of repeated administrations of sucrose in neonates needs to be investigated. Use of sucrose in neonates that are very low birth weight, unstable and/or ventilated also needs to be addressed. (ABSTRACT TRUNCATED)

Prevention and management of pain and stress in the neonate

This statement is intended for health care professionals caring for neonates (preterm to one month of age). The objectives of this statement are to: increase awareness that neonates experience pain; provide a physiological basis for neonatal pain and stress assessment and management by health care professionals; make recommendations for reduced exposure of the neonate to noxious stimuli and to minimize associated adverse outcomes; and recommend effective and safe interventions that relieve pain and stress.