Do cry features reflect pain intensity in preterm neonates? A preliminary study

Sucrose analgesia for heel-lance procedures in neonates

BACKGROUND

Sucrose has been examined for calming and pain-relieving effects in neonates for invasive procedures such as heel lance.

OBJECTIVES

To assess the effectiveness of sucrose for relieving pain from heel lance in neonates in terms of immediate and long-term outcomes SEARCH METHODS: We searched (February 2022): CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, Web of Science, and three trial registries.

SELECTION CRITERIA

We included randomised controlled trials where term and/or preterm neonates received sucrose for heel lances. Comparison treatments included water/placebo/no intervention, non-nutritive sucking (NNS), glucose, breastfeeding, breast milk, music, acupuncture, facilitated tucking, and skin-to-skin care.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We reported mean differences (MD) with 95% confidence intervals (CI) using the fixed-effect model for continuous outcome measures. We assessed heterogeneity by the I2 test. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included 55 trials (6273 infants): 29 included term neonates, 22 included preterm neonates, and four included both. Heel lance was investigated in 50 trials; 15 investigated other minor painful procedures in addition to lancing. Sucrose vs control The evidence suggests that sucrose probably results in a reduction in PIPP scores compared to the control group at 30 seconds (MD -1.74 (95% CI -2.11 to -1.37); I2 = 62%; moderate-certainty evidence) and 60 seconds after lancing (MD -2.14, 95% CI -3.34 to -0.94; I2 = 0%; moderate-certainty evidence). The evidence is very uncertain about the effects of sucrose on DAN scores compared to water at 30 seconds after lancing (MD -1.90, 95% CI -8.58 to 4.78; heterogeneity not applicable (N/A); very low-certainty evidence). The evidence suggests that sucrose probably results in a reduction in NIPS scores compared to water immediately after lancing (MD -2.00, 95% CI -2.42 to -1.58; heterogeneity N/A; moderate-certainty evidence). Sucrose vs NNS The evidence is very uncertain about the effect of sucrose on PIPP scores compared to NNS during the recovery period after lancing (MD 0.60, 95% CI -0.30 to 1.50; heterogeneity not applicable; very low-certainty evidence) and on DAN scores at 30 seconds after lancing (MD -1.20, 95% CI -7.87 to 5.47; heterogeneity N/A; very low-certainty evidence). Sucrose + NNS vs NNS The evidence is very uncertain about the effect of sucrose + NNS on PIPP scores compared to NNS during lancing (MD -4.90, 95% CI -5.73 to -4.07; heterogeneity not applicable; very low-certainty evidence) and during recovery after lancing (MD -3.80, 95% CI -4.47 to -3.13; heterogeneity N/A; very low-certainty evidence). The evidence is very uncertain about the effects of sucrose + NNS on NFCS scores compared to water + NNS during lancing (MD -0.60, 95% CI -1.47 to 0.27; heterogeneity N/A; very low-certainty evidence). Sucrose vs glucose The evidence suggests that sucrose results in little to no difference in PIPP scores compared to glucose at 30 seconds (MD 0.26, 95% CI -0.70 to 1.22; heterogeneity not applicable; low-certainty evidence) and 60 seconds after lancing (MD -0.02, 95% CI -0.79 to 0.75; heterogeneity N/A; low-certainty evidence). Sucrose vs breastfeeding The evidence is very uncertain about the effect of sucrose on PIPP scores compared to breastfeeding at 30 seconds after lancing (MD -0.70, 95% CI -0.49 to 1.88; I2 = 94%; very low-certainty evidence). The evidence is very uncertain about the effect of sucrose on COMFORTneo scores compared to breastfeeding after lancing (MD -2.60, 95% CI -3.06 to -2.14; heterogeneity N/A; very low-certainty evidence). Sucrose vs expressed breast milk The evidence suggests that sucrose may result in little to no difference in PIPP-R scores compared to expressed breast milk during (MD 0.3, 95% CI -0.24 to 0.84; heterogeneity not applicable; low-certainty evidence) and at 30 seconds after lancing (MD 0.3, 95% CI -0.11 to 0.71; heterogeneity N/A; low-certainty evidence). The evidence suggests that sucrose probably may result in slightly increased PIPP-R scores compared to expressed breast milk 60 seconds after lancing (MD 1.10, 95% CI 0.34 to 1.86; heterogeneity N/A; low-certainty evidence). The evidence is very uncertain about the effect of sucrose on DAN scores compared to expressed breast milk 30 seconds after lancing (MD -1.80, 95% CI -8.47 to 4.87; heterogeneity N/A; very low-certainty evidence). Sucrose vs laser acupuncture There was no difference in PIPP-R scores between sucrose and music groups; however, data were reported as medians and IQRs. The evidence is very uncertain about the effect of sucrose on NIPS scores compared to laser acupuncture during lancing (MD -0.86, 95% CI -1.43 to -0.29; heterogeneity N/A; very low-certainty evidence). Sucrose vs facilitated tucking The evidence is very uncertain about the effect of sucrose on total BPSN scores compared to facilitated tucking during lancing (MD -2.27, 95% CI -4.66 to 0.12; heterogeneity N/A; very low-certainty evidence) and during recovery after lancing (MD -0.31, 95% CI -1.72 to 1.10; heterogeneity N/A; very low-certainty evidence). Sucrose vs skin-to-skin + water (repeated lancing) The evidence suggests that sucrose results in little to no difference in PIPP scores compared to skin-to-skin + water at 30 seconds after 1st (MD 0.13, 95% CI -0.70 to 0.96); 2nd (MD -0.56, 95% CI -1.57 to 0.45); or 3rd lancing (MD-0.15, 95% CI -1.26 to 0.96); heterogeneity N/A, low-certainty evidence for all comparisons. The evidence suggests that sucrose results in little to no difference in PIPP scores compared to skin-to-skin + water at 60 seconds after 1st (MD -0.61, 95% CI -1.55 to 0.33); 2nd (MD -0.12, 95% CI -0.99 to 0.75); or 3rd lancing (MD-0.40, 95% CI -1.48 to 0.68); heterogeneity N/A, low-certainty evidence for all comparisons. Minor adverse events required no intervention.

AUTHORS' CONCLUSIONS

Sucrose compared to control probably results in a reduction of PIPP scores 30 and 60 seconds after single heel lances (moderate-certainty evidence). Evidence is very uncertain about the effect of sucrose compared to NNS, breastfeeding, laser acupuncture, facilitated tucking, and the effect of sucrose + NNS compared to NNS in reducing pain. Sucrose compared to glucose, expressed breast milk, and skin-to-skin care shows little to no difference in pain scores. Sucrose combined with other nonpharmacologic interventions should be used with caution, given the uncertainty of evidence.

A Scientometric Review of Infant Cry and Caregiver Responsiveness: Literature Trends and Research Gaps over 60 Years of Developmental Study

Infant cry is an adaptive signal of distress that elicits timely and mostly appropriate caring behaviors. Caregivers are typically able to decode the meaning of the cry and respond appropriately, but maladaptive caregiver responses are common and, in the worst cases, can lead to harmful events. To tackle the importance of studying cry patterns and caregivers' responses, this review aims to identify key documents and thematic trends in the literature as well as existing research gaps. To do so, we conducted a scientometric review of 723 documents downloaded from Scopus and performed a document co-citation analysis. The most impactful publication was authored by Barr in 1990, which describes typical developmental patterns of infant cry. Six major research thematic clusters emerged from the analysis of the literature. Clusters were renamed "Neonatal Pain Analyzer" (average year of publication = 2002), "Abusive Head Trauma" (average year of publication = 2007), "Oxytocin" (average year of publication = 2009), "Antecedents of Maternal Sensitivity" (average year of publication = 2010), "Neurobiology of Parental Responses" (average year of publication = 2011), and "Hormonal Changes & Cry Responsiveness" (average year of publication = 2016). Research clusters are discussed on the basis of a qualitative inspection of the manuscripts. Current trends in research focus on the neurobiology of caregiver responses and the identification of factors promoting maternal sensitivity. Recent studies have also developed evidence-based strategies for calming crying babies and preventing caregivers' maladaptive responses. From the clusters, two topics conspicuously call for future research: fathers' responsiveness to infant cry and the impact of caregiver relationship quality on cry responsiveness.

Evaluation of the Reliability and Validity of the Behavioral Indicators of Infant Pain Scale in Chinese Neonates

BACKGROUND

Behavioral Indicators of Infant Pain scale (BIIP) has been shown to be a good tool to assess pain in infants.

AIMS

This paper aimed to translate BIIP into Chinese and evaluate its reliability and validity for neonates in China.

DESIGN

A prospective observational study. SETTING AND PARTICIPANTS: A convenience sample of 396 neonates (preterm and term infants) were recruited from neonatal intensive care units in China from July to October 2016.

METHODS

The BIIP was translated and adjusted for semantic adaption.396 neonates were assessed during 3 phases of blood collection from an artery/vein. A video camera was positioned for a close-up view of the face and body. The neonates' pain was rated independently by 2 nurses who were trained and familiar with the Chinese version of BIIP (C-BIIP)and FLACC (Facial expression, Legs, Activity, Crying and Consolability).

RESULTS

The internal consistency were 0.904 (preterm) and 0.895 (term). The test-retest reliability were 0.947 (preterm) and 0.938 (term) and the interclass correlation coefficients were 0.921 to 0.959 (preterm) and 0.921 to 0.959 (term). The correlations between the C-BIIP and FLACC were high (preterm: r = 0.948, term: r = 0.896). Using the C-BIIP, the 3 phases of blood collection were found to be statistically different (preterm: F = 635.76, term: F = 675.54; P < 0.001), which showed that the construct validity of C-BIIP was good.

CONCLUSION

The BIIP is a reliable and valid tool to assess pain in term and preterm neonates in China.

Pain and Sedation Scales for Neonatal and Pediatric Patients in a Preverbal Stage of Development: A Systematic Review

IMPORTANCE

Because children in a preverbal stage of development are unable to voice their feelings, they completely depend on their caregiving team for the interpretation and management of their pain and discomfort. Thus, accurately validated scales to assess pain and sedation levels are crucial.

OBJECTIVE

To provide clinicians a complete overview on the validity and reliability of the existing pain and sedation scales for different target populations (preterm infants, term infants, and toddlers) and in different clinical contexts.

EVIDENCE REVIEW

BIOSIS Previews, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Embase, MEDLINE, PsycCRITIQUES, PsycINFO, PSYNDEXplus Literature and Audiovisual Media, and PSYNDEXplus Tests were the databases screened from their inception to August 2018. All studies examining the validity or reliability of a given pain or sedation scale for patients in a preverbal stage of development were included in this systematic review. Those scales that were tested for at least construct validity, internal consistency, and interrater reliability were subsequently scored using the consensus-based standards for the selection of health measurement instruments (COSMIN) checklist.

FINDINGS

In total, 89 validation articles comprising 65 scales were included. Fifty-seven scales (88%) were useful for assessing pain, 13 scales (20%) for assessing sedation, and 4 scales (6%) for assessing both conditions. Forty-two (65%) were behavioral scales, and 23 (35%) were multidimensional scales. Eleven scales (17%) were validated for infants on mechanical ventilation. Thirty-seven scales (57%) were validated for preterm infants, 24 scales (37%) for term and preterm infants, 7 scales (11%) for term-born children, 7 scales (11%) for preterm infants, term infants, and toddlers, and 17 scales (26%) for term infants and toddlers. Twenty-eight scales (43%) considered construct validity, internal consistency, and interrater reliability.

CONCLUSIONS AND RELEVANCE

Clinicians should consider using scales that are validated for at least construct validity, internal consistency, and interrater reliability, combining this information with the population of interest and the construct the scale is intended to measure.

Phonetic characteristics of vocalizations during pain

INTRODUCTION AND OBJECTIVES

There have, yet, been only few attempts to phonetically characterize the vocalizations of pain, although there is wide agreement that moaning, groaning, or other nonverbal utterance can be indicative of pain. We studied the production of vowels "u," "a," "i", and "schwa" (central vowel, sounding like a darker "e" as in hesitations like "ehm")-as experimental approximations to natural vocalizations.

METHODS

In 50 students vowel production and self-report ratings were assessed during painful and nonpainful heat stimulation (hot water immersion) as well as during baseline (no-stimulation). The phonetic parameters extracted were pitch (mean F₀), phonatory fluctuations (range F₀) and loudness (acoustic energy level).

RESULTS

Only for the vowels "u" and "schwa," which might be considered best approximations to moaning and groaning, did pitch and loudness increase during pain. Furthermore, changes from nonpainful to painful stimulations in these parameters also significantly predicted concurrent changes in pain ratings.

CONCLUSION

Vocalization characteristics of pain seem to be best described by an increase in pitch and in loudness. Future studies using more specific and comprehensive phonetic analyses will surely help to provide an even more precise characterization of vocalizations because of pain.

Sucrose for analgesia in newborn infants undergoing painful procedures

BACKGROUND

Administration of oral sucrose with and without non-nutritive sucking is the most frequently studied non-pharmacological intervention for procedural pain relief in neonates.

OBJECTIVES

To determine the efficacy, effect of dose, method of administration and safety of sucrose for relieving procedural pain in neonates as assessed by validated composite pain scores, physiological pain indicators (heart rate, respiratory rate, saturation of peripheral oxygen in the blood, transcutaneous oxygen and carbon dioxide (gas exchange measured across the skin - TcpO2, TcpCO2), near infrared spectroscopy (NIRS), electroencephalogram (EEG), or behavioural pain indicators (cry duration, proportion of time crying, proportion of time facial actions (e.g. grimace) are present), or a combination of these and long-term neurodevelopmental outcomes.

SEARCH METHODS

We used the standard methods of the Cochrane Neonatal. We performed electronic and manual literature searches in February 2016 for published randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library, Issue 1, 2016), MEDLINE (1950 to 2016), EMBASE (1980 to 2016), and CINAHL (1982 to 2016). We did not impose language restrictions.

SELECTION CRITERIA

RCTs in which term or preterm neonates (postnatal age maximum of 28 days after reaching 40 weeks' postmenstrual age), or both, received sucrose for procedural pain. Control interventions included no treatment, water, glucose, breast milk, breastfeeding, local anaesthetic, pacifier, positioning/containing or acupuncture.

DATA COLLECTION AND ANALYSIS

Our main outcome measures were composite pain scores (including a combination of behavioural, physiological and contextual indicators). Secondary outcomes included separate physiological and behavioural pain indicators. We reported a mean difference (MD) or weighted MD (WMD) with 95% confidence intervals (CI) using the fixed-effect model for continuous outcome measures. For categorical data we used risk ratio (RR) and risk difference. We assessed heterogeneity by the I(2) test. We assessed the risk of bias of included trials using the Cochrane 'Risk of bias' tool, and assessed the quality of the evidence using the GRADE system.

MAIN RESULTS

Seventy-four studies enrolling 7049 infants were included. Results from only a few studies could be combined in meta-analyses and for most analyses the GRADE assessments indicated low- or moderate-quality evidence. There was high-quality evidence for the beneficial effect of sucrose (24%) with non-nutritive sucking (pacifier dipped in sucrose) or 0.5 mL of sucrose orally in preterm and term infants: Premature Infant Pain Profile (PIPP) 30 s after heel lance WMD -1.70 (95% CI -2.13 to -1.26; I(2) = 0% (no heterogeneity); 3 studies, n = 278); PIPP 60 s after heel lance WMD -2.14 (95% CI -3.34 to -0.94; I(2) = 0% (no heterogeneity; 2 studies, n = 164). There was high-quality evidence for the use of 2 mL 24% sucrose prior to venipuncture: PIPP during venipuncture WMD -2.79 (95% CI -3.76 to -1.83; I(2) = 0% (no heterogeneity; 2 groups in 1 study, n = 213); and intramuscular injections: PIPP during intramuscular injection WMD -1.05 (95% CI -1.98 to -0.12; I(2) = 0% (2 groups in 1 study, n = 232). Evidence from studies that could not be included in RevMan-analyses supported these findings. Reported adverse effects were minor and similar in the sucrose and control groups. Sucrose is not effective in reducing pain from circumcision. The effectiveness of sucrose for reducing pain/stress from other interventions such as arterial puncture, subcutaneous injection, insertion of nasogastric or orogastric tubes, bladder catherization, eye examinations and echocardiography examinations are inconclusive. Most trials indicated some benefit of sucrose use but that the evidence for other painful procedures is of lower quality as it is based on few studies of small sample sizes. The effects of sucrose on long-term neurodevelopmental outcomes are unknown.

AUTHORS' CONCLUSIONS

Sucrose is effective for reducing procedural pain from single events such as heel lance, venipuncture and intramuscular injection in both preterm and term infants. No serious side effects or harms have been documented with this intervention. We could not identify an optimal dose due to inconsistency in effective sucrose dosage among studies. Further investigation of repeated administration of sucrose in neonates is needed. There is some moderate-quality evidence that sucrose in combination with other non-pharmacological interventions such as non-nutritive sucking is more effective than sucrose alone, but more research of this and sucrose in combination with pharmacological interventions is needed. Sucrose use in extremely preterm, unstable, ventilated (or a combination of these) neonates needs to be addressed. Additional research is needed to determine the minimally effective dose of sucrose during a single painful procedure and the effect of repeated sucrose administration on immediate (pain intensity) and long-term (neurodevelopmental) outcomes.

Oral sucrose administration to reduce pain response during immunization in 16-19-month infants: a randomized, placebo-controlled trial

Although the analgesic effect of sucrose on newborns is well established, little is known about whether these solutions are effective in reducing procedural pain in infants beyond the newborn period. The purpose of this study was to determine the effect of sucrose solution given orally on infant crying times and measure the distress in a 16-19-month age group. A total of 537 healthy, 16-19-month-old infants attending for their immunizations with intramuscular diphtheria, tetanus, and acellular pertussis (DTaP)/Haemophilus influenza type b/IPV (along with oral polio vaccination (OPV)), intramuscular pneumococcus and intramuscular hepatitis A were randomized to receive 2 mL of a 75 % sucrose solution, a 25 % sucrose solution or sterile water 2 min before injections. Infants receiving a 75 % sucrose solution had significantly reduced total crying times and Children's Hospital of Eastern Ontario Pain Scale scores (CHEOPS) compared with infants in the control and 25 % sucrose solution groups (p < 0.001).

CONCLUSION

Sucrose solution reduces infant distress and is safe and clinically useful even for 16-19-month-old infants.

Role of sucrose in reducing painful response to orogastric tube insertion in preterm neonates

OBJECTIVES

To study whether orogastric tube (OGT) insertion elicits a painful response in preterm neonates, and the role of oral sucrose in reducing this pain.

METHODS

This double blinded, randomized control trial was conducted in the neonatal intensive care units of Kalawati Saran Children's Hospital. Clinically stable preterms within the first 7 postnatal days, who had not received painful stimulus 30 min prior to intervention, and who required routine OGT insertion were included. Lingual 24 % sucrose or distilled water (1 ml) was administered 2 min before OGT insertion. The primary outcome was painful response assessed by Premature Infant Pain Profile scale (PIPP), while the secondary outcomes were heart rate and SpO2 changes. The trial is registered with ClinicalTrials.gov (

REGISTRATION NUMBER

NCT 00949104) RESULTS: Sixty preterms were randomized in each group. Final analysis was carried out on 52 subjects in the placebo group and 53 in the sucrose group. The mean intra-procedure PIPP scores were significantly higher than the mean pre-procedure PIPP scores, in the gestational age groups of more than 34 wk, and 32 wk to 33 wk, 6 d, in both the placebo (7.25 vs. 3, and 8.14 vs. 3.14, respectively) and sucrose arm (8.06 vs. 3.21, and 7.18 vs. 4.18, respectively). The mean PIPP scores assessed at 30 s post procedure in the sucrose group were significantly lower than the placebo group (4.32 vs. 5.6, p = 0.014). No significant adverse events were seen.

CONCLUSIONS

OGT insertion causes pain in preterms and single dose lingual 24 % sucrose may alleviate this pain.

Sucrose for analgesia in newborn infants undergoing painful procedures

BACKGROUND

Administration of oral sucrose with and without non-nutritive sucking is the most frequently studied non-pharmacological intervention for procedural pain relief in neonates.

OBJECTIVES

To determine the efficacy, effect of dose and safety of oral sucrose for relieving procedural pain in neonates.

SEARCH METHODS

We used the standard methods of the Cochrane Neonatal Review Group. Electronic and manual searches were performed in November 2011 for published randomised controlled trials (RCTs) in MEDLINE (1950 to November 2011), EMBASE (1980 to 2011), CINAHL (1982 to November 2011) and the Cochrane Central Register of Controlled Trials (The Cochrane Library). We did not impose language restrictions.

SELECTION CRITERIA

RCTs in which term, preterm, or both term and preterm neonates (postnatal age maximum of 28 days after reaching 40 weeks' postmenstrual age) received sucrose for procedural pain. Control conditions included no treatment, water, pacifier, positioning/containing or breastfeeding.

DATA COLLECTION AND ANALYSIS

Main outcome measures were physiological, behavioural, or both pain indicators with or without composite pain scores. A mean difference (MD) with 95% confidence intervals (CI) using the fixed-effect model was reported for continuous outcome measures. Trial quality was assessed as per The Cochrane Collaboration

MAIN RESULTS

Fifty-seven studies enrolling 4730 infants were included. Results from only a few studies could be combined in meta-analyses. When Premature Infant Pain Profile (PIPP) scores were pooled, sucrose groups had significantly lower scores at 30 seconds (weighted mean difference (WMD) -1.76; 95% CI -2.54 to - 0.97; 4 trials; 264 neonates] and 60 seconds (WMD -2.05; 95% CI -3.08 to -1.02; 3 trials' 195 neonates) post-heel lance. For retinopathy of prematurity (ROP) examinations, sucrose did not significantly reduce PIPP scores (WMD -0.65; 95% CI -1.88 to 0.59; 3 trials; 82 neonates). There were no differences in adverse effects between sucrose and control groups. Sucrose significantly reduced duration of total crying time (WMD -39 seconds; 95% CI -44 to -34; 2 trials; 88 neonates), but did not reduce duration of first cry during heel lance (WMD -9 seconds; 95% CI -20 to 2; 3 trials; 192 neonates). Oxygen saturation (%) was significantly lower in infants given sucrose during ROP examination compared to controls (WMD -2.6; 95% CI -4.9 to - 0.2; 2 trials; 62 neonates). Results of individual trials that could not be incorporated in meta-analyses supported these findings. The effects of sucrose on long-term neurodevelopmental outcomes are unknown.

AUTHORS' CONCLUSIONS

Sucrose is safe and effective for reducing procedural pain from single events. An optimal dose could not be identified due to inconsistency in effective sucrose dosage among studies. Further investigation on repeated administration of sucrose in neonates and the use of sucrose in combination with other non-pharmacological and pharmacological interventions is needed. Sucrose use in extremely preterm, unstable, ventilated (or a combination of these) neonates needs to be addressed. Additional research is needed to determine the minimally effective dose of sucrose during a single painful procedure and the effect of repeated sucrose administration on immediate (pain intensity) and long-term (neurodevelopmental) outcomes.

Contextual factors associated with pain response of preterm infants to heel-stick procedures

BACKGROUND

Evidence indicates that medical and demographic contextual factors (cFs) impact pain responses in preterm neonates, but the existing evidence is very heterogeneous.

AIM

To explore the effect of cFs on pain responses to heel-stick procedures of preterm infants.

METHODS

This study was a secondary analysis of data collected during a randomized controlled trial examining pain response to non-pharmacological interventions across repeated heel sticks. Five heel sticks across the first 14 days of life were videotaped. Pain response was rated with the Bernese Pain Scale for Neonates (BPSN) by four raters blinded to the heel-stick phases (baseline, heel stick, recovery). Demographic and medical cFs were extracted from medical charts. Mixed single and multiple regression analyses were performed controlling for the intervention group, site and heel-stick phase.

RESULTS

Apgar scores at 1 min were negatively associated with behavioural (p = 0.002) BPSN scores, while Apgar scores at 5 min after birth were positively associated with behavioural (p = 0.006) scores. Accumulated number of painful procedures (p = 0.002) and gender (p = 0.02) were positively associated with physiological scores while continuous positive airway pressure CPAP (p = 0.009) and mechanical ventilation (p = 0.005) were negatively associated.

CONCLUSION

Higher exposure to painful procedures, male infants and having CPAP or mechanical ventilation were cFs associated with physiological response. The only variables significantly associated with behavioural BPSN scores were Apgar scores but these relationships were inconsistent.

Assessment of acute pain in children: development of evidence-based guidelines

AIM

Detecting children's pain in a healthcare setting can be improved by facilitating pain expression in ways that are appropriate to the child's cognitive development and that can be recognised by their carers. To ensure up-to-date guidance on assessing pain in children, the Royal College of Nursing undertook an evidence-based update of pain assessment guidelines, initially published in 2000.

METHODS

Following systematic review of the psychometric testing literature, a two-stage critical appraisal process was developed to derive a list of robust tools that could be recommended for use in a variety of settings to assess the intensity of a child's acute pain. Studies were appraised on the basis of their relevance to this topic and according to prespecified quality criteria. Tools were assessed for inclusion in guideline recommendations according to minimum validity and reliability thresholds.

RESULTS

Overall the quality of literature was poor, limited by small samples, lack of control groups, unblinded raters and convenience sampling. Twenty-four tools are recommended for use with infants and verbal children without cognitive impairment, 11 of which are purely self-report tools. Eight tools are recommended for use with neonates, some of which require concurrent physiological measures. Four tools are considered valid for use in children with cognitive impairment. All of these tools had shown reliability and validity according to the criteria established for this review.

CONCLUSION

The tools are presented in user-friendly tables that include a guide to their key features and the setting and age groups in which they have been validated. They are accompanied by good practice recommendations from experts and recommendations relating to timing and triggers for pain assessment. These outputs are some of those associated with the full guidelines and supporting material published on the Royal College of Nursing website (http://www.rcn.org.uk/childrenspainguideline).

Assessing pain in preterm infants in the neonatal intensive care unit: moving to a 'brain-oriented' approach

Preterm infants in the neonatal intensive care unit undergo repeated exposure to procedural and ongoing pain. Early and long-term changes in pain processing, stress-response systems and development may result from cumulative early pain exposure. So that appropriate treatment can be given, accurate assessment of pain is vital, but is also complex because these infants' responses may differ from those of full-term infants. A variety of uni- and multidimensional assessment tools are available; however, many have incomplete psychometric testing and may not incorporate developmentally important cues. Near-infrared spectroscopy and/or EEG techniques that measure neonatal pain responses at a cortical level offer new opportunities to validate neonatal pain assessment tools.

Sucrose for analgesia in newborn infants undergoing painful procedures

BACKGROUND

Administration of oral sucrose with and without non-nutritive sucking is frequently used as a non-pharmacological intervention for procedural pain relief in neonates.

OBJECTIVES

To determine the efficacy, effect of dose and safety of oral sucrose for relieving procedural pain in neonates.

SEARCH STRATEGY

The standard methods of the Cochrane Neonatal Collaborative Review Group were used.

SELECTION CRITERIA

Randomized controlled trials in which term and/or preterm neonates (postnatal age maximum of 28 days corrected for postmenstrual age) received sucrose for procedural pain. Control conditions included water, pacifier, positioning/containing or breastfeeding.

DATA COLLECTION AND ANALYSIS

The main outcome measures were physiological and/or behavioural pain indicators and/or composite pain scores. A weighted mean difference (WMD) with 95% confidence intervals (CI) using the fixed effects model was reported for continuous outcome measures.

MAIN RESULTS

Forty-four studies enrolling 3,496 infants were included. Results from only a few studies could be combined in meta-analyses. Sucrose significantly reduced duration of total crying time (seconds) [WMD -39.26 (95% CI -44.29, -34.24), 88 neonates], but did not reduce duration of first cry (seconds) during heel lance [WMD -8.99 (95% CI -20.07, 2.10), 192 neonates]. No significant differences were found for percent change in heart rate from baseline at one minute [WMD 0.90 (95% CI -5.81, 7.61), 86 neonates] and three minutes [WMD -6.20 (95% CI -15.27, 2.88), 86 neonates] post-heel lance, or for mean heart rate at three minutes post-heel lance [WMD -0.98 (95% CI -8.29, 6.32), 154 neonates]. Oxygen saturation (%) was significantly lower in infants given sucrose during ROP examination compared to controls [WMD -2.58 (95% CI -4.94, - 0.23), 62 neonates]. Infants given sucrose post-heel lance had significantly lower PIPP scores at 30 seconds [WMD -1.64 (95% CI -2.47, - 0.81), 220 neonates] and 60 seconds [WMD -2.05 (95% CI -3.08, -1.02), 195 neonates]. For ROP exams, sucrose did not significantly reduce PIPP scores [WMD -0.65 (95% CI -1.88, 0.59), 82 neonates]. There were no differences in adverse effects between sucrose and control groups.

AUTHORS' CONCLUSIONS

Sucrose is safe and effective for reducing procedural pain from single events. An optimal dose could not be identified due to inconsistency in effective sucrose dosage among studies.Further investigation on repeated administration of sucrose in neonates and the use of sucrose in combination with other non-pharmacological (e.g. behavioural, physical) and pharmacologic interventions is needed. Sucrose use in extremely low birth-weight and unstable and/or ventilated neonates needs to be addressed.

Kangaroo Care (skin contact) reduces crying response to pain in preterm neonates: pilot results

Crying commonly occurs in response to heel stick and adversely affects the infant's physiologic stability. Minimal crying in response to pain is desired. "Kangaroo Care," skin contact between mother and infant, reduces pain and may reduce crying in response to pain. The purpose of this pilot study was to test Kangaroo Care's effect on the preterm infant's audible and inaudible crying response to heel stick. Inaudible crying has not been previously studied. A prospective randomized cross-over study with 10 preterm infants 2-9 days old (30-32 weeks' postmenstrual age) was conducted. Infants were randomly assigned to two sequences (sequence A: day 1 heel stick in Kangaroo Care [after 30 min of prone skin contact upright between maternal breasts] and day 2 heel stick in incubator [inclined, nested and prone]; or sequence B: opposite of sequence A) was conducted. Videotapes of baseline, heel warming, heel stick, and recovery phases were scored for audible and inaudible crying times. Audible and inaudible crying times for each subject in each phase were summed and analyzed by repeated-measures analysis of variance. Subject characteristics did not differ between those in the two sequences. Crying time differed between the study phases on both days (p <or= .001). When in Kangaroo Care compared with the incubator, crying time was less during the heel stick (p = .001) and recovery (p = .01) phases, regardless of sequence. Because Kangaroo Care reduced crying in response to heel stick in medically stable preterm infants, a definitive study is merited before making recommendations.

Analgesic properties of oral sucrose during routine immunizations at 2 and 4 months of age

OBJECTIVE

The purpose of this work was to evaluate the analgesic properties of oral sucrose during routine immunizations in infants at 2 and 4 months of age.

PATIENTS AND METHODS

A prospective, randomized, placebo-controlled clinical trial was conducted at a pediatric ambulatory care clinic. One-hundred healthy term infants scheduled to receive routine immunizations were recruited, randomly stratified into 2- or 4-month study groups, and further randomly assigned to receive 24% oral sucrose and pacifier or the sterile water control solution. The study preparations were administered 2 minutes before the combined diphtheria-tetanus-acellular pertussis, inactivated polio vaccine, and hepatitis B vaccine. Haemophilus influenzae type b vaccine was administered 3 minutes after the combined injection, followed by the pneumococcal conjugate vaccine, 2 minutes after the H. influenzae type b injection. The University of Wisconsin Children's Hospital Pain Scale measured serial acute pain responses for the treatment and control groups at baseline and 2, 5, 7, and 9 minutes after solution administration. Repeated-measures analysis of variance examined between-group differences and within-subject variability of treatment effect on overall pain scores.

RESULTS

Two- and 4-month-old infants receiving oral sucrose (n = 38) displayed reductions in pain scores 2 minutes after solution administration compared with 2- and 4-month-old infants in the placebo group (n = 45). Between-group comparisons for the oral sucrose and placebo groups showed lower pain responses at 5, 7, and 9 minutes after solution administration. The oral sucrose and placebo groups demonstrated their highest mean pain score at 7 minutes, with a mean pain score of 3.8 and 4.8, respectively. At 9 minutes, the placebo group had a mean pain score of 2.91 whereas the mean pain score for the oral sucrose group returned to near baseline, reflecting a 78.5% difference in mean pain score (oral sucrose - placebo) relative to the placebo mean.

CONCLUSIONS

Oral sucrose is an effective, easy-to-administer, short-acting analgesic for use during routine immunizations.

Is the ABC pain scale reliable for premature babies?

AIM

We recently developed the ABC scale to assess pain in term newborns. The aim of the present study was to assess the reliability of the scale in preterm babies.

MATERIAL AND METHODS

The scale consists of three cry parameters: (a) pitch of the first cry, (b) rhythmicity of the bout of crying and (c) cry constancy. Changes in these parameters were previously found to distinguish medium and high levels of pain as evaluated by spectral analysis of crying. We enrolled 72 babies to perform the steps usually requested to validate a scale, namely the study of the concurrent validity, specificity and sensibility. Moreover, we assessed the interjudge reliability and the clinical utility and ease of the scale.

RESULTS

A good correlation (r = 0.68; r(2)= 0.45; p < 0.0001) was found between scores obtained with the ABC scale and the premature infant pain profile (PIPP) scale, demonstrating a good concurrent validity. The scale also showed good sensitivity and specificity (we found statistically significant differences between mean values of scores obtained in babies who underwent pain and babies who underwent non-painful stimulus.) Interobserver reliability was good: Cohen's kappa = 0.7.

CONCLUSION

The good correlation between the two scales shows that the ABC scale is also reliable for premature babies.

Neonatal Facial Coding System Scores and Spectral Characteristics of Infant Crying During Newborn Circumcision

OBJECTIVE

To determine the relations between Neonatal Facial Coding System (NFCS) scores and measures of infant crying during newborn circumcision.

METHODS

Video and audio recordings were made of infant facial activity and cry sounds, respectively, during the lysis phase of circumcisions of 44 healthy term males (<3 d of age). All infants received topical analgesia before circumcision. NFCS scores were determined by blinded assistant from video recordings of facial activity. Measures of infant crying were determined via spectrum analysis of audio recordings by a blinded, independent researcher. Pearson product-moment correlations were used to examine relationship between NFCS scores and measures of crying. Principal component factor analysis detected dimensions underlying related measures of crying. Factor scores from a factor analysis were used in stepwise linear regression to predict NFCS scores.

RESULTS

Higher NFCS scores correlated with lower peak fundamental frequency of crying (P<0.01) and with higher amplitudes of crying at peak fundamental frequency and dominant frequency and in overall cry sample (P<0.01). The factor analysis showed 3 significant orthogonal dimensions underlying measures of crying: Power and Velocity (amplitude and rapidity), Pitch of Crying (frequency characteristics), and Infant Arousal (turbulence and intensity) accounting for 42.3%, 17.8%, and 14.6% of variance, respectively. A regression analysis showed all 3 factor scores accounted for significant and separate portions of variance (P<0.001). The best predictor of NFCS score was Power and Velocity (P<0.002), followed by Infant Arousal (P<0.002), and Pitch of Crying (P<0.007).

DISCUSSION

These data provide some of the first known evidence linking specific measures of infant crying with an independent, validated measure of pain.

Prevention and management of pain in the neonate. An update

The prevention of pain in neonates should be the goal of all caregivers, because repeated painful exposures have the potential for deleterious consequences. Neonates at greatest risk of neurodevelopmental impairment as a result of preterm birth (ie, the smallest and sickest) are also those most likely to be exposed to the greatest number of painful stimuli in the NICU. Although there are major gaps in our knowledge regarding the most effective way to prevent and relieve pain in neonates, proven and safe therapies are currently underused for routine minor yet painful procedures. Every health care facility caring for neonates should implement an effective pain-prevention program, which includes strategies for routinely assessing pain, minimizing the number of painful procedures performed, effectively using pharmacologic and nonpharmacologic therapies for the prevention of pain associated with routine minor procedures, and eliminating pain associated with surgery and other major procedures.

Prevention and management of pain in the neonate: an update

The prevention of pain in neonates should be the goal of all caregivers, because repeated painful exposures have the potential for deleterious consequences. Neonates at greatest risk of neurodevelopmental impairment as a result of preterm birth (ie, the smallest and sickest) are also those most likely to be exposed to the greatest number of painful stimuli in the NICU. Although there are major gaps in our knowledge regarding the most effective way to prevent and relieve pain in neonates, proven and safe therapies are currently underused for routine minor yet painful procedures. Every health care facility caring for neonates should implement an effective pain-prevention program, which includes strategies for routinely assessing pain, minimizing the number of painful procedures performed, effectively using pharmacologic and nonpharmacologic therapies for the prevention of pain associated with routine minor procedures, and eliminating pain associated with surgery and other major procedures.

Neonatal pain analyzer: development and validation

We developed a pain analyzer (ABC analyzer) to perform automatic acoustic analysis of neonatal crying and to provide an objective estimate of neonatal pain. The ABC analyzer uses a validated pain scale (ABC scale) based on three acoustic parameters: pitch frequency, normalized RMS amplitude, and presence of a characteristic frequency- and amplitude-modulated crying feature, defined as "siren cry". Here we assessed the reliability of the analyzer. We enrolled 57 healthy neonates. Each baby was recorded with a video camera during heel prick. Pain intensity was evaluated using a validated scale [Douleur Aigue du Nouveau-Né (DAN) scale] and the analyzer and the two scores were compared. We found a statistically significant concordance between the DAN score and ABC analyzer score (p < 0.0001). The ABC analyser is a novel approach to cry analysis that should now have its properties carefully evaluated in a series of studies, just as is necessary in the development of any other pain measurement tool.

Summary proceedings from the neonatal pain-control group

Recent advances in neurobiology and clinical medicine have established that the fetus and newborn may experience acute, established, and chronic pain. They respond to such noxious stimuli by a series of complex biochemical, physiologic, and behavioral alterations. Studies have concluded that controlling pain experience is beneficial with respect to short-term and perhaps long-term outcomes. Yet, pain-control measures are adopted infrequently because of unresolved scientific issues and lack of appreciation for the need for control of pain and its long-term sequelae during the critical phases of neurologic maturation in the preterm and term newborn. The neonatal pain-control group, as part of the Newborn Drug Development Initiative (NDDI) Workshop I, addressed these concerns. The specific issues addressed were (1) management of pain associated with invasive procedures, (2) provision of sedation and analgesia during mechanical ventilation, and (3) mitigation of pain and stress responses during and after surgery in the newborn infant. The cross-cutting themes addressed within each category included (1) clinical-trial designs, (2) drug prioritization, (3) ethical constraints, (4) gaps in our knowledge, and (5) future research needs. This article provides a summary of the discussions and deliberations. Full-length articles on procedural pain, sedation and analgesia for ventilated infants, perioperative pain, and study designs for neonatal pain research were published in Clinical Therapeutics (June 2005).

Skin-to-Skin Contact (Kangaroo Care) Analgesia for Preterm Infant Heel Stick

The purpose of the study was to compare a heel stick conducted during Kangaroo Care (skin-to-skin contact) with the mother to a heel stick in a warmer in reducing premature infant physiologic and behavioral pain responses. Twenty-four premature infants in a university-based neonatal intensive care unit were recruited and randomized to 2 sequences: sequence A group received 3 hours of Kangaroo Care (with a heel stick in Kangaroo Care) followed by 3 hours in a warmer (with a heel stick in the warmer). Sequence B group had warmer care and a heel stick (in the warmer) before Kangaroo Care and a heel stick (in Kangaroo Care). Heart rate, respiratory rate, oxygen saturation, crying time, and behavioral state were measured before, during, and after heel stick. Repeated measures ANOVA and Mann Whitney U statistics were performed. Heart rate and length of crying in response to pain were significantly reduced during Kangaroo Care and the Kangaroo Care heel stick as compared to when infants were in the warmer and had a heel stick in the warmer. Three infants did not cry at all during the Kangaroo Care heel stick; infants slept more during Kangaroo Care than in the warmer. Kangaroo Care positioning before and during heel stick is a simple and inexpensive analgesic intervention to ameliorate pain in stable premature infants.

A systematic integrative review of infant pain assessment tools

PURPOSE

To examine the issue of pain assessment in infants by acquiring all available published pain assessment tools and evaluating their reported reliability, validity, clinical utility, and feasibility.

DESIGN AND METHODS

A systematic integrative review of the literature was conducted using the following databases: MEDLINE and CINAHL (through February 2004), and Health and Psychosocial Instruments, and Cochrane Systematic Reviews (through 2003). MeSH headings searched included "pain measurement," with limit of "newborn infant"; "infant newborn"; and "pain perception."

SUBJECTS

Thirty-five neonatal pain assessment tools were found and evaluated using predetermined criteria. The critique consisted of a structured comparison of the classification and dimensions measured. Further, the population tested and reports of reliability, validity, clinical utility, and feasibility were reviewed.

RESULTS

Of the 35 measures reviewed, 18 were unidimensional and 17 were multidimensional. Six of the multidimensional measures were published as abstracts only, were not published at all, or the original work could not be obtained. None of the existing instruments fulfilled all criteria for an ideal measure; many require further psychometric testing.

CONCLUSIONS

When choosing a pain assessment tool, one must also consider the infant population and setting, and the type of pain experienced. The decision should be made after carefully considering the existing published options. Confidence that the instrument will assess pain in a reproducible way is essential, and must be demonstrated with validity and reliability testing. Using an untested instrument is not recommended, and should only occur within a research protocol, with appropriate ethics and parental approval. Because pain is a multidimensional phenomenon, well-tested multidimensional instruments may be preferable.

Does prone or supine position influence pain responses in preterm infants at 32 weeks gestational age?

OBJECTIVE

The purpose of this study was to examine the influence of prone and supine position in preterm infants during acute pain of blood collection.

SETTING

Level III Neonatal Intensive Care Unit (NICU).

STUDY DESIGN

Thirty-eight preterm infants (birthweight 1339 [590-2525] g, GA 29 [25- 32] wks) were in 2 groups depending on their position in the isolette prior to and during heel lance at 32 weeks post-conceptional age. The study design was a comparison between groups (Prone, Supine) during 2 events (Baseline, Heel lance).

OUTCOME MEASURE

Pain measures were multidimensional, including behavioral (sleep-wake state and facial activity) and physiological (heart rate) responses measured continuously prior to (Baseline) and during blood collection (Lance).

RESULTS

Both groups of infants displayed statistically significant shifts in sleep-wake state to greater arousal, and increased facial activity and heart rate, from Baseline to Lance. Prone position was associated with significantly more deep sleep during Baseline, compared with Supine position, but there were no differences in sleep-wake state during Lance. Minor increased facial activity was shown in some time segments of Baseline for infants in Supine compared with Prone, but did not differ overall between positions. Prone and Supine position did not affect heart rate significantly during Baseline or Lance events.

CONCLUSIONS

Prone position promotes deep sleep in preterm neonates at 32 weeks post-conceptional age when they are undisturbed. However, placement in prone position is not a sufficient environmental comfort intervention for painful invasive procedures such as heel lance for blood sampling in the NICU. Neonates require other environmental supports to promote coping with this stressful event.

Behavioral and Physiological Indicators of Procedural and Postoperative Pain in High‐Risk Infants

Nurses play a critical role in the assessment and management of infant pain. In this article, infant pain assessment tools that are valid, reliable, clinically sensitive, and developmentally appropriate are discussed. Their purpose, use in acute pain, and applicability for premature and newborn infant populations are described. Behavioral and physiological indicators of pain, sleep-wake states, and infant development are discussed as important considerations in pain assessment. Recommendations for improving pain assessment practices are offered in conclusion.

Cry features reflect pain intensity in term newborns: an alarm threshold

The purpose of this study was to assess differences in sound spectra of crying of term newborns in relation to different pain levels. Fifty-seven consecutively born neonates were evaluated during heel-prick performed with different analgesic techniques. Crying was recorded and frequency spectrograms analyzed. A pain score on the DAN (Douleur Aiguë du Nouveau-né) scale was assigned to each baby after the sampling. Three features were considered and correlated with the corresponding DAN scores: 1) whole spectral form; 2) the fundamental frequency of the first cry emitted (F0); and 3) root mean square sound pressure normalized to its maximum. After emission of the first cry, babies with DAN scores >8, but not with DAN scores < or =8 (p < 0.001), showed a pattern ("siren cry") characterized by a sequence of almost identical cries with a period on the order of 1 s. A statistically significant correlation was found between root mean square (r2 = 89%, p < 0.01), F0 (r2 = 32%, p < 0.05), siren cry (r2 = 68.2%, p = 0.02), and DAN score. F0 did not show significant correlation with DAN score in the subset of neonates with DAN scores < or =8 (r2 = 1.4%, p = 0.94), and babies with a DAN score >8 had a significantly higher F0 than those with lower DAN scores (p = 0.016). An alarm threshold exists between high (>8) and low (< or =8) DAN scores: crying has different features in these two groups. When pain exceeds a DAN score of 8, usually a first cry at a high pitch is emitted, followed by the siren cry, with a sound level maintained near its maximum.

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 validated individual pain indicators and composite pain scores.

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 - March 2004, EMBASE from 1980-2004 and search of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2004). Key words and (MeSH) terms included infant/newborn, pain, analgesia and sucrose. Language restrictions were not imposed. Bibliographies, personal files, the most recent relevant neonatal and pain journals and recent major pediatric pain conference proceedings were searched manually. Unpublished studies, or studies reported only as abstracts, were not included. Additional information from published studies was obtained.

SELECTION CRITERIA

RCTs in which term and/or preterm neonates (postnatal age maximum of 28 days after reaching 40 weeks corrected gestational age) received sucrose via oral syringe, NG-tube, dropper or pacifier for procedural pain from heel lance or venepuncture. In the control group, water, pacifier or positioning/containing were used. Studies in which the painful stimulus was circumcision were excluded.

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 three investigators.

STATISTICAL ANALYSIS

The statistical package (RevMan 4.2) of the Cochrane Collaboration was used. For meta-analysis, a weighted mean difference (WMD) with 95% confidence intervals (CI) using the fixed effects model was reported for continuous outcome measures.

MAIN RESULTS

Forty-four studies were identified for possible inclusion in this review. Seven studies reported only as abstracts, and sixteen additional studies were excluded, leaving 21 studies (1,616 infants) included in this review. Sucrose in a wide variety of dosages was generally found to decrease physiologic (heart rate) and behavioural (the mean percent time crying, total cry duration, duration of first cry, and facial action) pain indicators and composite pain scores in neonates undergoing heel stick or venepuncture. When pain scores (Premature Infant Pain Profiles) were pooled across 3 studies (Gibbins 2001; Johnston 1999a; Stevens 1999), they were significantly reduced in infants who were given sucrose (dose range 0.012 g to 0.12 g) compared to the control group, [WMD -1.64 (95% CI -2.47,- 0.81); p = 0.0001] at 30 seconds and [WMD -2.05, (95% CI -3.08, -1.02); p = 0.00010] at 60 seconds after heel lance. When results for change in heart rate were pooled for two studies (Haouari 1995, Isik 2000), there were no significant differences between changes in heart rate for infants given sucrose (dose range 0.5 g to 0.6 g) compared to the control group, [WMD 0.90 (95% CI -5.81, 7.61); p = 0.8] at one minute and [WMD -6.20 (95% CI -15.27, 2.88); p = 0.18] at three minutes after heel lance.

REVIEWERS' CONCLUSIONS

Sucrose is safe and effective for reducing procedural pain from single painful events (heel lance, venepuncture). There was inconsistency in the dose of sucrose that was effective (dose range of 0.012 g to 0.12 g), and therefore an optimal dose to be used in preterm and/or term infants could not be identified. The use of repeated administrations of sucrose in neonates needs to be investigated as does the use of sucrose in combination with other behavioural (e.g., facilitated tucking, kangaroo care) and pharmacologic (e.g., morphine, fentanyl) interventions. Use of sucrose in neonates who are of very low birth weight, unstable and/or ventilated also needs to be addressed.

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.

Infant crying: nature, physiologic consequences, and select interventions

This article describes the nature of infant crying, the physiologic events and changes associated with it, and appropriate nursing interventions for infant crying. A cry is a series of four movements that basically resembles a Valsalva maneuver. Documented immediate and long-term sequelae of crying include increased heart rate and blood pressure, reduced oxygen level, elevated cerebral blood pressure, initiation of the stress response, depleted energy reserves and oxygen, interrupted mother-infant interaction, brain injury, and cardiac dysfunction. Caregivers are encouraged to answer infant cries swiftly, consistently, and comprehensively. Kangaroo care is an efficient method for preventing, minimizing, and halting crying. Other interventions for crying include swaddled holding, a pacifier, sugar water, a sweet-tasting nonsucrose solution, heartbeat sounds, distraction by lullabies or mother's voice, rhythmic movement, and reduction of external stimuli.

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.

Assessment of the effect of EMLA during venipuncture in the newborn by analysis of heart rate variability

The objective of this study was to investigate the effect of EMLA on the pain response when venipuncture was performed in 60 3-day-old healthy newborns. EMLA/placebo was applied to the back of the baby's hand, following a randomized, double-blind procedure. ECG and crying were recorded during the test. The incidence of crying, heart rate (HR) and spectral analysis of heart rate variability were used to characterize the reaction of the baby to the venipuncture procedure. The occurrence of crying during venipuncture did not differ significantly between the EMLA and the placebo groups. The placebo-treated group showed a statistically significant higher HR, and a decrease in variance (total power) and power in the low-frequency band (0.02-0.15 Hz) when compared with the EMLA group. We conclude that EMLA decreases the stress response during venipuncture in newborn infants.

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)