Effects of perinatal pain and stress

Prolonged pain in premature neonates hospitalised in neonatal intensive care units: A scoping review

BACKGROUND

Exposure to repetitive pain during the neonatal period has been shown to have important short and long-term effects on the neurodevelopment of the premature neonate and can contribute to experienced prolonged pain. A uniform taxonomy of neonatal prolonged pain is still lacking to this day which contributes to suboptimal prolonged pain management in neonatal intensive care units. Accordingly, a scoping review exploring the state of knowledge about prolonged pain in preterm neonates hospitalised in the neonatal intensive care unit will contribute to the developing field of neonatal prolonged pain and provide recommendations for clinical prolonged pain management.

OBJECTIVE

To determine the scope, extent, and nature of the available literature on prolonged pain in premature neonates hospitalised in neonatal intensive care units.

DESIGN

Scoping review.

METHODS

An electronic search was conducted from inception to November 2023 in the databases of CINAHL, PubMed, Medline, Web of Science, GeryLit.org and Grey Source Index. Included studies discussed concepts related to neonatal prolonged pain such as definitions of prolonged pain, indicators of prolonged pain, contexts that result in prolonged pain, prolonged pain evaluation tools, consequences of prolonged pain and interventions for prolonged pain management.

RESULTS

Key concepts of neonatal prolonged pain were identified in the 86 included articles of this scoping review such as definitions (n = 26), indicators (n = 39), contexts (n = 49), scales (n = 56), consequences of prolonged pain (n = 30) and possible interventions for prolonged pain management (n = 22). Whilst a consensus on a definition has yet to be achieved, no proximate event was shown to cause prolonged pain and a time criterion was identified by authors as being relevant in defining prolonged pain. Interestingly, the context of hospitalisation was identified as being the most indicative of prolonged pain in premature neonates and should guide its evaluation and management, whilst only limited pain management interventions and consequences were discussed.

CONCLUSION

The findings of this scoping review contribute to the foundation of growing knowledge in neonatal prolonged pain and shed light on the ambiguity that currently exists on this topic in the scientific literature. This review summarises knowledge of key concepts necessary for a better understanding of prolonged pain and stresses the importance of considering contexts of hospitalisation for prolonged pain evaluation and management in neonatal intensive care units, with the objective of improving developmental outcomes of premature neonates.

TWEETABLE ABSTRACT

A scoping review reveals that the contexts of prolonged pain in premature neonates hospitalised in the neonatal intensive care unit are essential in guiding its evaluation and management.

Non-pharmacological interventions for the prevention of pain during endotracheal suctioning in ventilated neonates

BACKGROUND

Pain, when treated inadequately, puts preterm infants at a greater risk of developing clinical and behavioural sequelae because of their immature pain system. Preterm infants in need of intensive care are repeatedly and persistently exposed to noxious stimuli, and this happens during a critical window of their brain development with peak rates of brain growth, exuberant synaptogenesis and the developmental regulation of specific receptor populations. Nearly two-thirds of infants born at less than 29 weeks' gestation require mechanical ventilation for some duration during the newborn period. These neonates are endotracheally intubated and require repeated endotracheal suctioning. Endotracheal suctioning is identified as one of the most frequent and most painful procedures in premature infants, causing moderate to severe pain. Even with improved nursing performance and standard procedures based on neonatal needs, endotracheal suctioning remains associated with mild pain.

OBJECTIVES

To evaluate the benefits and harms of non-pharmacological interventions for the prevention of pain during endotracheal suctioning in mechanically ventilated neonates. Non-pharmacological interventions were compared to no intervention, standard care or another non-pharmacological intervention.

SEARCH METHODS

We conducted searches in June 2023 in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, Embase, CINAHL and three trial registries. We searched the reference lists of related systematic reviews, and of studies selected for inclusion.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), quasi-RCTs and cluster-RCTs that included term and preterm neonates who were mechanically ventilated via endotracheal tube or via tracheostomy tube and required endotracheal suctioning performed by doctors, nurses, physiotherapists or other healthcare professionals.

DATA COLLECTION AND ANALYSIS

Our main outcome measures were validated composite pain scores (including a combination of behavioural, physiological and contextual indicators). Secondary outcomes included separate physiological and behavioural pain indicators. We used standard methodological procedures expected by Cochrane. For continuous outcome measures, we used a fixed-effect model and reported mean differences (MDs) with 95% confidence intervals (CIs). For categorical outcomes, we reported the typical risk ratio (RR) and risk difference (RD) and 95% CIs. We assessed risk of bias using the Cochrane RoB 1 tool, and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included eight RCTs (nine reports), which enroled 386 infants, in our review. Five of the eight studies were included in a meta-analysis. All studies enrolled preterm neonates. Facilitated tucking versus standard care (four studies) Facilitated tucking probably reduces Premature Infant Pain Profile (PIPP) score during endotracheal suctioning (MD -2.76, 95% CI 3.57 to 1.96; I² = 82%; 4 studies, 148 infants; moderate-certainty evidence). Facilitated tucking probably has little or no effect during endotracheal suctioning on: heart rate (MD -3.06 beats per minute (bpm), 95% CI -9.33 to 3.21; I² = 0%; 2 studies, 80 infants; low-certainty evidence); oxygen saturation (MD 0.87, 95% CI -1.33 to 3.08; I² = 0%; 2 studies, 80 infants; low-certainty evidence); or stress and defensive behaviours (SDB) (MD -1.20, 95% CI -3.47 to 1.07; 1 study, 20 infants; low-certainty evidence). Facilitated tucking may result in a slight increase in self-regulatory behaviours (SRB) during endotracheal suctioning (MD 0.90, 95% CI 0.20 to 1.60; 1 study, 20 infants; low-certainty evidence). No studies reported intraventricular haemorrhage (IVH). Familiar odour versus standard care (one study) Familiar odour during endotracheal suctioning probably has little or no effect on: PIPP score (MD -0.30, 95% CI -2.15 to 1.55; 1 study, 40 infants; low-certainty evidence); heart rate (MD -6.30 bpm, 95% CI -16.04 to 3.44; 1 study, 40 infants; low-certainty evidence); or oxygen saturation during endotracheal suctioning (MD -0.80, 95% CI -4.82 to 3.22; 1 study, 40 infants; low-certainty evidence). No studies reported SRB, SDB or IVH. White noise (one study) White noise during endotracheal suctioning probably has little or no effect on PIPP (MD -0.65, 95% CI -2.51 to 1.21; 1 study, 40 infants; low-certainty evidence); heart rate (MD -1.85 bpm, 95% CI -11.46 to 7.76; 1 study, 40 infants; low-certainty evidence); or oxygen saturation (MD 2.25, 95% CI -2.03 to 6.53; 1 study, 40 infants; low-certainty evidence). No studies reported SRB, SDB or IVH.

AUTHORS' CONCLUSIONS

Facilitated tucking / four-handed care / gentle human touch probably reduces PIPP score. The evidence of a single study suggests that facilitated tucking / four-handed care / gentle human touch slightly increases self-regulatory and approach behaviours during endotracheal suctioning. Based on a single study, familiar odour and white noise have little or no effect on any of the outcomes compared to no intervention. The use of expressed breast milk or oral sucrose suggests that there is no discernible advantage of one method over the other for reducing pain during endotracheal suctioning. None of the studies reported on any of the prespecified secondary outcomes of adverse events.

Pharmacological interventions for the management of pain and discomfort during lumbar puncture in newborn infants

BACKGROUND

Lumbar puncture (LP) is a common invasive procedure, most frequently performed to diagnose infection. Physicians perform LP in newborn infants with the help of an assistant using a strict aseptic technique; it is important to monitor the infant during all the steps of the procedure. Without adequate analgesia, LP can cause considerable pain and discomfort. As newborns have increased sensitivity to pain, it is crucial to adequately manage the procedural pain of LP in this population.

OBJECTIVES

To assess the benefits and harms, including pain, discomfort, and success rate, of any pharmacological intervention during lumbar puncture in newborn infants, compared to placebo, no intervention, non-pharmacological interventions, or other pharmacological interventions.

SEARCH METHODS

We searched CENTRAL, PubMed, Embase, and three trial registries in December 2022. We also screened the reference lists of included studies and related systematic reviews for studies not identified by the database searches.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs comparing drugs used for pain management, sedation, or both, during LP. We considered the following drugs suitable for inclusion. • Topical anesthetics (e.g. eutectic mixture of local anesthetics [EMLA], lidocaine) • Opioids (e.g. morphine, fentanyl) • Alpha-2 agonists (e.g. clonidine, dexmedetomidine) • N-Methyl-D-aspartate (NMDA) receptor antagonists (e.g. ketamine) • Other analgesics (e.g. paracetamol) • Sedatives (e.g. benzodiazepines such as midazolam) DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used the fixed-effect model with risk ratio (RR) for dichotomous data and mean difference (MD) or standardized mean difference (SMD) for continuous data, with their 95% confidence intervals (CIs). Our main outcomes were successful LP on first attempt, total number of LP attempts, episodes of bradycardia, pain assessed with validated scales, episodes of desaturation, number of episodes of apnea, and number of infants with one or more episodes of apnea. We used the GRADE approach to evaluate the certainty of the evidence.

MAIN RESULTS

We included three studies (two RCTs and one quasi-RCT) that enrolled 206 newborns. One study included only term infants. All studies assessed topical treatment versus placebo or no intervention. The topical anesthetics were lidocaine 4%, lidocaine 1%, and EMLA. We identified no completed studies on opioids, non-steroidal anti-inflammatory drugs, alpha-2 agonists, NMDA receptor antagonists, other analgesics, sedatives, or head-to-head comparisons (drug A versus drug B). Based on very low-certainty evidence from one quasi-RCT of 100 LPs in 76 infants, we are unsure if topical anesthetics (lidocaine), compared to no anesthesia, has an effect on the following outcomes. • Successful LP on first attempt (first-attempts success in 48% of LPs in the lidocaine group and 42% of LPs in the control group) • Number of attempts per LP (mean 1.9 attempts, [standard error of the mean 0.2] in the lidocaine group, and mean 2.1 attempts [standard error of the mean 2.1] in the control group) • Episodes of bradycardia (0% of LPs in the lidocaine group and 4% of LPs in the control group) • Episodes of desaturation (0% of LPs in the lidocaine group and 8% of LPs in the control group) • Occurrence of apnea (RR 3.24, 95% CI 0.14 to 77.79; risk difference [RD] 0.02, 95% CI -0.03 to 0.08). Topical anesthetics compared to placebo may reduce pain assessed with the Neonatal Facial Coding System (NFCS) score (SMD -1.00 standard deviation (SD), 95% CI -1.47 to -0.53; I² = 98%; 2 RCTs, 112 infants; low-certainty evidence). No studies in this comparison reported total number of episodes of apnea. We identified three ongoing studies, which will assess the effects of EMLA, lidocaine, and fentanyl. Three studies are awaiting classification.

AUTHORS' CONCLUSIONS

The evidence is very uncertain about the effect of topical anesthetics (lidocaine) compared to no anesthesia on successful lumbar puncture on first attempt, the number of attempts per lumbar puncture, episodes of bradycardia, episodes of desaturation, and occurrence of apnea. Compared to placebo, topical anesthetics (lidocaine or EMLA) may reduce pain assessed with the NFCS score. One ongoing study will assess the effects of systemic treatment.

Effects of fentanyl and sucrose on pain in retinopathy examinations with pain scale, near-infrared spectroscopy, and ultrasonography: a randomized trial

BACKGROUND

This study aimed to compare the efficacy of intravenous, intranasal fentanyl and oral sucrose in reducing the pain response during retinopathy of prematurity examinations using premature infant pain profile (PIPP) scores.

METHOD

The study included 42 infants who underwent retinopathy screening examinations. The infants were divided into three groups: oral sucrose, intranasal fentanyl, and intravenous fentanyl. Vital signs (heart rate, arterial oxygen saturation, and mean arterial pressure) were recorded. The PIPP was used to determine pain severity. Cerebral oxygenation and middle cerebral artery blood flow were evaluated using near-infrared spectroscopy and Doppler ultrasonography, respectively. The data obtained were compared between groups.

RESULTS

There was no significant difference between the three groups regarding postconceptional and postnatal ages or birth weights and weight at the time of examination. All babies had moderate pain during the examination. No correlation was observed between analgesia method and pain scores (P = 0.159). In all three groups, heart rate and mean arterial pressure increased, whereas oxygen saturation decreased during the exam compared with pre-examination values. However, heart rate (HR), mean arterial pressure (MAP) and arterial oxygen saturation (sPO2) values did not differ between groups (HR, P = 0.150; MAP, P = 0.245; sPO2, P = 0.140). The cerebral oxygenation (rSO2) values between the three groups were found to be similar [rSO2: P = 0.545, P = 0.247, P = 0.803; fractional tissue oxygen extraction (FTOE): P = 0.553, P = 0.278]. Regarding cerebral blood flow values, we also did not find any difference between the three groups [mean blood flow velocity (Vmean): P = 0.569, P = 0.975; maximum flow velocity (Vmax): P = 0.820, P = 0.997].

CONCLUSIONS

Intravenous and intranasal fentanyl and oral sucrose were not superior to each other in preventing pain during the examination for retinopathy of prematurity (ROP). Sucrose may be a good alternative for pain control during ROP examination. Our findings suggest that ROP exam may not affect cerebral oxygenation or cerebral blood flow. Larger scale studies are needed to determine the best pharmacological option to reduce pain during ROP exams and evaluate the effects of this procedure on cerebral oxygenation and blood flow.

Analgesia and sedation for intratracheal intubation in the neonatal period: an integrative literature review

OBJECTIVE

to assess evidence available in the literature about the use of sedation and analgesia for intratracheal intubation of newborns.

DATA SOURCES

by means of an integrative literature review, the authors looked for evidence related to the theme from the last ten years, indexed in the Pubmed, Medline, Lilacs, Scielo, and Scopus databases, by combining the descriptors: newborn, intratracheal intubation, and analgesia. Articles in Portuguese, English, and Spanish that met the research purpose were included.

DATA SUMMARY

After applying the eligibility criteria, ten articles on the topic were obtained, predominantly narrative reviews, retrospective studies, observational studies, and only one non-randomized clinical trial, which characterizes the literature related to the topic as having a low level of scientific evidence. There is still no consensus in the literature on which medications and indications are for use in non-elective intubations, despite the ethical recommendation.

DISCUSSION

pain and its deleterious effects should not be neglected. Neonatal Intensive Care Units should have their own protocols regarding sedation and analgesia for intubation considering the individual characteristics of each patient. There is an ethical recommendation regarding the use of sedation and analgesia for intubation since it is a known painful procedure.

Body size and brain volumetry in the rat following prolonged morphine administration in infancy and adulthood

Background

Prolonged morphine treatment in infancy is associated with a high incidence of opioid tolerance and dependence, but our knowledge of the long-term consequences of this treatment is sparse. Using a rodent model, we examined the (1) short- and (2) long-term effects of prolonged morphine administration in infancy on body weight and brain volume, and (3) we evaluated if subsequent dosing in adulthood poses an increased brain vulnerability.

Methods

Newborn rats received subcutaneous injections of either morphine or equal volume of saline twice daily for the first two weeks of life. In adulthood, animals received an additional two weeks of saline or morphine injections before undergoing structural brain MRI. After completion of treatment, structural T2-weigthed MRI images were acquired on a 7 T preclinical scanner (Bruker) using a RARE FSE sequence. Total and regional brain volumes were manually extracted from the MRI images using ITK-SNAP (v.3.6). Regions of interest included the brainstem, the cerebellum, as well as the forebrain and its components: the cerebral cortex, hippocampus, and deep gray matter (including basal ganglia, thalamus, hypothalamus, ventral tegmental area). Absolute (cm³) and normalized (as % total brain volume) values were compared using a one-way ANOVA with Tukey HSD post-hoc test.

Results

Prolonged morphine administration in infancy was associated with lower body weight and globally smaller brain volumes, which was not different between the sexes. In adulthood, females had lower body weights than males, but no difference was observed in brain volumes between treatment groups. Our results are suggestive of no long-term effect of prolonged morphine treatment in infancy with respect to body weight and brain size in either sex. Interestingly, prolonged morphine administration in adulthood was associated with smaller brain volumes that differed by sex only in case of previous exposure to morphine in infancy. Specifically, we report significantly smaller total brain volume of female rats on account of decreased volumes of forebrain and cortex.

Conclusions

Our study provides insight into the short- and long-term consequences of prolonged morphine administration in an infant rat model and suggests brain vulnerability to subsequent exposure in adulthood that might differ with sex.

Pharmacological interventions for the management of pain and discomfort during lumbar puncture in newborn infants

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the benefits and harms, including pain, discomfort, and success rate, of any pharmacological intervention during lumbar puncture in newborn infants, compared to placebo, no intervention, non‐pharmacological interventions, or other pharmacological interventions.

Efficacy of Skin-to-Skin Care versus Swaddling for Pain Control Associated with Vitamin K Administration in Full-Term Neonates: A Randomized Controlled Trial

OBJECTIVE

The objective of the study was to assess the efficacy of immediate skin-to-skin care (SSC) versus swaddling in pain response to intramuscular injection of vitamin K at 30 min of birth in neonates.

METHODS

Healthy full-term newborns were enrolled immediately after normal vaginal delivery and randomized in two groups, SSC and swaddling. Neonatal Infant Pain Scale (NIPS) was measured before, immediately after and at 2 min after the injection.

RESULTS

Total 100 newborns were enrolled in the study (50 in each group). The mean (SD) birth weight of newborns in the SSC and swaddling group was 2668 (256) and 2730 (348) g, respectively. NIPS was comparable between the SSC and swaddling at before [1.78 (0.58) vs. 1.96 (0.83), p = 0.21], and immediately after the injection [4.82 (0.72) vs. 5.08 (0.75), p = 0.08]. NIPS at 2 min after the injection was significantly low in the SSC group compared to the swaddling group [1.38 (0.70) vs. 2.88 (1.00), p < 0.001]. At 2 min after injection, the NIPS score was significantly lower than baseline in the SSC group (p = 0.002), while it was significantly higher in the swaddling group (p < 0.001). A significantly higher proportion of newborns had a NIPS score of more than three at 2 min after injection in the swaddling group as compared to the SSC group (22% vs. 2%, p < 0.001).

CONCLUSION

Immediate SSC was more efficacious as compared to swaddling as a pain control intervention while giving vitamin K injection.

CLINICAL TRIAL REGISTRATION

The trial is registered with the Clinical Trial Registry of India with Registration number: CTRI/2020/01/022984.

Fentanyl Exposure in Preterm Infants: Five-Year Neurodevelopmental and Socioemotional Assessment

Objective

To evaluate the association between cumulative fentanyl dose during neonatal intensive care and 5-year neurodevelopmental and socioemotional outcomes in very preterm infants.

Materials and Methods

Patient demographics and clinical factors during the perinatal and neonatal course were collected in 84 patients born between 23- and 30-weeks gestational age (GA). Cumulative fentanyl dose during neonatal intensive care was calculated. Developmental testing at age 5 years included the Wechsler Preschool and Primary Scale of Intelligence Full-Scale Intelligence Quotient, Third Edition, Clinical Evaluation of Language Fundamentals-Preschool, Second Edition, Movement Assessment Battery for Children, Second Edition (MABC-2), and Shape School Assessment. Socioemotional outcomes were assessed via caregiver's responses on the Child Behavior Checklist/1.5-5 (CBCL/1.5-5.5) and Social Responsiveness Scale, Second Edition (SRS-2). Covariates were identified on bivariate analysis (p < 0.1). Linear regression models related outcome measures to the log of cumulative fentanyl dose adjusted for covariates.

Results

Higher cumulative fentanyl dose was associated with lower composite motor scores on bivariate analysis (p < 0.01). Cumulative fentanyl dose did not correlate with composite intelligence quotient, language, or executive function. The Clinical Risk Index for Babies score, log of mechanical ventilation, inotrope, and anesthesia duration, and log of cumulative midazolam and hydrocortisone dose were also associated with MABC-2 scores (p < 0.1). Cumulative fentanyl dose was not associated with composite MABC-2 scores on multiple linear regression. Higher cumulative fentanyl dose was associated with decreased socioemotional problems based on caregiver's response on CBCL/1.5-5.5 t-scores driven by fewer symptoms of depression. The McMaster Family Assessment Device general functioning scale score, maternal age, GA, log of total parenteral nutrition days, patent ductus arteriosus requiring treatment, and log of inotrope hours were also associated with CBCL/1.5-5.5 t-scores (p < 0.1). Cumulative fentanyl dose (p = 0.039) and family dysfunction score (p = 0.002) remained significant after controlling for covariates on multiple linear regression.

Conclusion

Cumulative fentanyl dose during neonatal intensive care did not correlate with 5-year motor, cognitive, or language outcomes after controlling for other variables. Fentanyl dose was associated with caregiver reported total socioemotional problems on the CBCL/1.5-5.5 on multivariate modeling. Additional long-term studies are needed to fully elucidate the safety of fentanyl in very preterm neonates.

Within amygdala: Basolateral parts are selectively impaired in premature-born adults

While it is known that whole amygdala volume is lastingly reduced after premature birth, it is unknown whether different amygdala nuclei are distinctively affected by prematurity. This question is motivated by two points: First, the observation that developmental trajectories of superficial, centromedial and basolateral amygdala nuclei are different. And second, the expectation that these different developmental pathways are distinctively affected by prematurity. Furthermore, we stated the question whether alterations in amygdala nuclei are associated with increased adults' anxiety traits after premature birth. We investigated 101 very premature-born adults (<32 weeks of gestation and/or birth weight below 1500 g) and 108 full-term controls of a prospectively and longitudinally collected cohort at 26 years of age using automated amygdala nuclei segmentation based on structural MRI. We found selectively reduced volumes of bilateral accessory basal nuclei (pertaining to the basolateral amygdala of claustral developmental trajectory) adjusted for whole amygdala volume. Volumes of bilateral accessory basal nuclei were positively associated with gestational age and negatively associated with duration of ventilation. Furthermore, structural covariance within the basolateral amygdala was increased in premature-born adults. We did not find an association between reduced volumes of basolateral amygdala and increased social anxiety in the prematurity group. These results demonstrate specifically altered basolateral amygdala structure in premature-born adults. Data suggest that prematurity has distinct effects on amygdala nuclei.

A Systematic Review of Clinical Practice Guidelines for Acute Procedural Pain on Neonates

OBJECTIVES

During hospitalization in neonatal intensive care units, neonates are exposed to many painful procedures within a stressful environment. To date, many evidence-based guidelines are available. However, the quality of these guidelines and their clinical application remain unclear. This systematic review aimed to determinie the quality of existing guidelines on the management of procedural pain in neonates and to summarize the recommendations provided by these guidelines.

MATERIALS AND METHODS

A structured search was conducted in Embase, PubMed, CINAHL, JBI database, and gray literature resources in November 2018 to identify relevant guidelines published from 2007 onward. Published guidelines and guidelines from complementary searches were included in the treating assessment or management of procedural pain in neonates. The methodological quality was analyzed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II Instrument.

RESULTS

A total of 1154 records were identified. After screening for eligibility, 17 guidelines were included in this review. Among these, 11 were identified to be high-quality guidelines. Besides the usual recommendations for pharmacological and nonpharmacological treatments, the inclusion of parents, improving interprofessional collaboration, and considering the setting were identified as important elements.

DISCUSSION

The results of this review show that there is a need to improve the methodological quality of guidelines for procedural pain in newborns. The set of recommendations for procedural pain prevention needs to involve not only pharmacological and nonpharmacological pain treatment but also parents and interprofessional collaboration. It is also essential to take into account facilitators, barriers, and the context to improve pain management.

Effects of Temperature and Position Change on Neonatal Brain Regional Oxygen Saturation in Tub Bathing: A Prospective Study

INTRODUCTION

A major goal in neonatal medicine is to reduce stress as much as possible in routine care. Bathing is one of the important routine cares for neonates, but it makes a big environmental change for them. We aimed to examine whether water temperature, room temperature, and position changes in tub bathing serve as noxious stimuli to neonates.

METHODS

This prospective trial was performed in full-term and non-low-birth-weight neonates admitted to the hospital between July 2020 and March 2021. Those with underlying diseases, fetal distress, infection, and other medical conditions were excluded. Measurements were taken during the neonates' first tub bath since birth, which was performed by a trained nurse. Changes in regional oxygen saturation (rSO₂), determined using near-infrared spectroscopy, and water and room temperature, were examined at five different time points: upon entering the bath, head washing, position change, exiting the bath, and during the 3 min after bathing.

RESULTS

In total, 17 neonates were analyzed. No changes in rSO₂ due to head washing or position change were observed; however, rSO₂ significantly decreased upon entering (78.5 ± 4.1% vs. 75.7 ± 4.1%, p < 0.001) and exiting the bath (75.8 ± 5.7% vs. 74.4 ± 5.4%, p < 0.04). The rate change in rSO₂ upon entering the bath showed a significant inverse correlation with water temperature (r =  - 0.53, p < 0.03), and there were no significant correlations between rSO₂ and water or room temperature upon exiting the bath. There was no change in body skin temperature before and after bathing, but rSO₂ gradually decreased during the 3 min after bathing.

CONCLUSIONS

Neonates may perceive certain temperatures during bathing as noxious stimuli. Therefore, methods to minimize stress associated with bathing should be implemented to reduce the difference between water temperature and room temperature during bathing.

TRIAL REGISTRATION

This trial has been registered at UMIN repository with the trial number UMIN000041045 ( https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000046500 ). The date of the final dataset was April 01, 2021.

Laser acupuncture versus oral glucose administration for pain prevention in term neonates: an observer-blinded non-inferiority randomized controlled clinical trial

BACKGROUND

Neonates undergoing intensive care are routinely submitted to minor painful procedures such as heel lances. Pharmacological treatment is limited in neonatal care and not recommended for minor painful interventions. Hence, non-pharmacological acute pain management is an important subject. Acupuncture could be a new strategy for neonatal pain prevention. Accordingly, the aim of the present study was to investigate whether laser acupuncture is non-inferior to oral sweet solutions in pain prevention.

METHODS

In total, 96 healthy term neonates were randomly assigned to receive either laser acupuncture with 10 mW at LI4 bilaterally (AG, acupuncture group) or 30% oral glucose solution (GG, glucose group) before heel lance for metabolic screening. The primary outcome was the difference in premature infant pain profile (PIPP) score between groups in a non-inferiority concept. Secondary outcomes were changes in heart rate and crying time.

RESULTS

Median (interquartile range) PIPP scores were comparable in the AG and GG (12 (10-14) vs 12 (9-14), p = 0.981). Nevertheless, the 95% confidence interval (CI) of location shift exceeded the predefined margin for non-inferiority of 1 (95% CI: -1.000006 to 1.000059). Heart rate was found to be significantly lower after intervention (p = 0.048) and after heel lance (p = 0.015) in the AG versus GG. There was no difference in crying time between groups (p = 0.890).

CONCLUSION

Laser acupuncture was not shown to be non-inferior to an oral glucose solution, possibly due to the higher than expected variability in PIPP scores within the studied groups. Future neonatal laser acupuncture studies for pain prevention with higher sample sizes are therefore warranted.

Decreased amygdala volume in adults after premature birth

Premature-born infants have impaired amygdala structure, presumably due to increased stress levels of premature birth mediated by the amygdala. However, accounting for lifelong plasticity of amygdala, it is unclear whether such structural changes persist into adulthood. To address this problem, we stated the following questions: first, are whole amygdala volumes reduced in premature-born adults? And second, as adult anxiety traits are often increased after prematurity and linked with amygdala structure, are alterations in amygdala associated with adults' anxiety traits after premature birth? We addressed these questions by automated amygdala segmentation of MRI volumes in 101 very premature-born adults (< 32 weeks of gestation and/or birth weight below 1500 g) and 108 full-term controls at 26 years of age of a prospectively and longitudinally collected cohort. We found significantly lower whole amygdala volumes in premature-born adults. While premature-born adults had significantly higher T score for avoidant personality reflecting increased social anxiety trait, this trait was not correlated with amygdala volume alterations. Results demonstrate reduced amygdala volumes in premature born adults. Data suggest lasting effects of prematurity on amygdala structure.

Pain control in neonatal male circumcision: A best evidence review

OBJECTIVE

Routine male infant circumcision (RMIC) is a common procedure that inadvertently causes significant but preventable pain. In this best evidence review, we examine the available pain management options and their effectiveness for RMIC.

MATERIAL AND METHODS

The Medline (OVID) and Cochrane library were searched for randomized controlled trials investigating pain control for RMIC. Only trials that included newborns younger than 45 days of age were included. The articles generated in the initial search were screened independently by two of the authors. A third reviewer settled any discrepancies about the inclusion. Then, trials were categorized based on the type of intervention: topical anesthetics, oral sucrose, oral acetaminophen, nerve blocks, caudal blocks, circumcision device, non-pharmacological adjuncts, and multiple combinations.

RESULTS

Twenty-nine randomized clinical trials (RCTs) were found to address pain preventative measures in RMIC. As single agent, nerve blocks outperformed topical anesthetics and oral sucrose, as the latter two proved to be insufficient for proper pain control. Additionally, dorsal penile nerve block and ring blocks have a reasonable safety profile. The use of caudal blocks in RMIC was uncommon. Oral sucrose in association with swaddling or music are helpful and can be easily combined with other methods of pain management. Moreover, oral acetaminophen given perioperatively helps the patient recover. Ultimately, pain control should rely on a combination of anesthetics, analgesics, and kinesthetic methods to be administered before, during, and after the procedure for optimal outcome.

CONCLUSION

RMIC is a painful procedure in need of proper pain control. Different interventions and agents have various abilities in controlling pain; however, developing a protocol centered around multimodal pain control proves to be the most effective.

Socially-Assistive Robots Using Empathy to Reduce Pain and Distress during Peripheral IV Placement in Children

Objectives

Socially-assistive robots (SAR) have been used to reduce pain and distress in children in medical settings. Patients who perceive empathic treatment have increased satisfaction and improved outcomes. We sought to determine if an empathic SAR could be developed and used to decrease pain and fear associated with peripheral IV placement in children.

Methods

We conducted a pilot study of children receiving IV placement. Participating children were randomized to interact with (1) no robot, or a commercially available 3D printed humanoid SAR robot programmed with (2) empathy or (3) distraction conditions. Children and parents completed demographic surveys, and children used an adapted validated questionnaire to rate the robot's empathy on an 8-point Likert scale. Survey scores were compared by the t-test or chi-square test. Pain and fear were measured by self-report using the FACES and FEAR scales, and video tapes were coded using the CHEOPS and FLACC. Scores were compared using repeated measures 2-way ANOVA. This trial is registered with NCT02840942.

Results

Thirty-one children with an average age of 9.6 years completed the study. For all measures, mean pain and fear scores were lowest in the empathy group immediately before and after IV placement. Children were more likely to attribute characteristics of empathy to the empathic condition (Likert score 7.24 v. 4.70; p=0.012) and to report that having the empathic vs. distraction robot made the IV hurt less (7.45 vs. 4.88; p=0.026).

Conclusions

Children were able to identify SAR designed to display empathic characteristics and reported it helped with IV insertion pain and fear. Mean scores of self-reported or objective pain and fear scales were the lowest in the empathy group and the highest in the distraction condition before and after IV insertion. This result suggests empathy improves SAR functionality when used for painful medical procedures and informs future research into SAR for pain management.

Prophylactic low-dose paracetamol administration associated with lowered rate of patent ductus arteriosus in preterm infants - Impact on outcome and pain perception

BACKGROUND

To determine the rate of patent ductus arteriosus after prophylactic low-dose paracetamol administration, the impact on outcome parameters, possible treatment side-effects and the influence on pain perception.

METHODS

We report retrospective single-centre outcome data of premature infants ≤ 32 weeks of gestation (n = 476). The intervention group received intravenous paracetamol, the control group obtained no preventive therapy. Ductal closure rate and outcome parameters were compared between the two groups. Adverse effects were determined by laboratory parameters. For the assessment of pain the Bernese Pain Scale for Neonates was used.

RESULTS

The rate of patent ductus arteriosus was significantly lower in the paracetamol-treated group compared to the control group (13.6% vs. 38.2%, p < 0.001). With regard to secondary outcome parameters, severe and moderate bronchopulmonary dysplasia (2.7% vs. 7.4%, p = 0.023), severe retinopathy of prematurity (0% vs. 4.4%, p = 0.002) and late onset sepsis (2.7% vs. 8.3%, p = 0.009) were significantly less frequent in the paracetamol group. Except for a 1.5-fold increased risk for hyperbilirubinemia (86.0% vs. 77.6%, p = 0.035) in the paracetamol group following treatment, no significant differences in laboratory parameters were found. Relating to pain, the administration of Glucose 33% was significantly more often necessary in the control group compared to the paracetamol-treated group (mean 13.48 vs. 8.71, p < 0.001), just as the need for additional treatment with systemic analgesics, which was more frequent in the control group (mean 0.72 vs. 0.57, p = 0.361).

CONCLUSION

In our study we were able to show a significantly lower rate of patent ductus arteriosus after prophylactic paracetamol administration without serious adverse effect, but a beneficial influence of this regime on the patient's pain perception.

Risk Factors for Functional Decline and Impaired Quality of Life after Pediatric Respiratory Failure

Rationale: Poor outcomes of adults surviving critical illness are well documented, but data in children are limited.Objectives: To identify factors associated with worse postdischarge function and health-related quality of life (HRQL) after pediatric acute respiratory failure.Methods: We assessed functional status at baseline, discharge, and 6 months after pediatric ICU discharge and HRQL 6 months after discharge in 2-week- to 17-year-olds mechanically ventilated for acute respiratory failure in the RESTORE (Randomized Evaluation of Sedation Titration for Respiratory Failure) trial. We assessed HRQL via Infant and Toddler Quality of Life Questionnaire-97 (<2 yr old) or Pediatric Quality of Life Inventory (≥2 yr old). We categorized patients with normal baseline function as having impaired HRQL if scores were greater than 1 SD below mean norms for Infant and Toddler Quality of Life Questionnaire-97 growth and development or Pediatric Quality of Life Inventory total score.Measurements and Main Results: One-fifth (n = 192) of 949 patients declined in function from baseline to postdischarge; 20% (55/271) had impaired growth and development; 19% (64/343) had impaired HRQL. In multivariable analyses, decline in function was associated with baseline impaired function, prematurity, cancer, respiratory failure etiology, ventilation duration, and clonidine (odds ratio [OR] = 2.14; 95% confidence interval [CI] = 1.22-3.76). Independent predictors of impaired growth and development included methadone (OR = 2.27; 95% CI = 1.18-4.36) and inadequate pain management (OR = 2.94; 95% CI = 1.39-6.19). Impaired HRQL was associated with older age, non-white or Hispanic race, cancer, and inadequate sedation management (OR = 3.15; 95% CI = 1.74-5.72).Conclusions: Postdischarge morbidity after respiratory failure is common and associated with admission factors, exposure to critical care therapies, and pain and sedation management.

[Clinical effect of maternal voice stimulation in alleviating procedural pain in hospitalized neonates]

OBJECTIVE

To study the clinical effect of maternal voice stimulation in alleviating procedural pain in neonates during heel blood collection.

METHODS

A total of 72 neonates who were admitted to the neonate intensive care unit were randomly divided into an intervention group (n=35) and a control group (n=37). Heel blood collection was performed by the routine method in the control group. The intervention group listened to their mothers' voice from 1 minute before heel blood collection to the end of the procedure. Pain score, incidence of crying, and vital signs were recorded before and after heel blood collection.

RESULTS

Compared with the control group, the heart rate was significantly reduced, the blood oxygen saturation significantly increased, the incidence of crying and the pain score were significantly reduced in the intervention group during the procedure of heel blood collection (P<0.05).

CONCLUSIONS

Maternal voice stimulation helps to reduce procedural pain and maintain stable vital signs in neonates.

Factors affecting Korean neonatal nurses' pain care: Psychometric evaluation of three instruments

AIM

The purpose of this study was to evaluate the psychometric properties of the Korean-language versions of Pain Knowledge and Use (PKU-K), Collaboration and Satisfaction About Care Decisions (CSACD-K), and Environmental Complexity Scale (ECS-K).

METHODS

A cross-sectional design was used with a convenience sample of 159 Korean nurses in seven neonatal intensive care units (NICUs). The data were collected by surveying the nurses with the PKU-K, CSACD-K, and ECS-K. Internal consistency reliability was assessed and Horn's parallel analysis, a confirmatory factor analysis, and a convergent construct validity test were conducted in order to evaluate the psychometric properties of the instruments.

RESULTS

The PKU-K, CSACD-K, and ECS-K exhibited strong internal consistency reliability. Horn's parallel analysis showed four factor structures for the PKU-K, one for the CSACD-K, and three for the ECS-K. The confirmatory factor analysis showed a good model fit for the PKU-K and CSACD-K, but the ECS-K model showed a poor fit. Most factor loadings were statistically significant. The CSACD-K's convergent validity was supported by significant correlations for collegial nurse-physician relations with a validated instrument.

CONCLUSION

The findings support the reliability and validity of the PKU-K, CSACD-K, and ECS-K for measuring nurses' knowledge about neonatal pain care, nurse-physician collaboration, and the work environment in NICUs. However, the ECS-K needs further refinement before it is applied to Korean NICU nurses.

Laser Acupuncture at Large Intestine 4 Compared with Oral Glucose Administration for Pain Prevention in Healthy Term Neonates Undergoing Routine Heel Lance: Study Protocol for an Observer-Blinded, Randomised Controlled Clinical Trial

Background

Nonpharmacological strategies have actually become more important in neonatal pain management during routinely applied minor painful procedures. However, commonly used nonpharmacological strategies are inferior to orally administered sweet solutions. Therefore, we will compare laser acupuncture, as a recent nonpharmacological method, with the standard care of oral glucose solution for pain prevention.

Methods

Ninety-five healthy term neonates will be allocated into one of two groups. Before routine heel lance for metabolic screening, one group will receive laser acupuncture at acupuncture point Large Intestine 4 (LI 4) bilaterally for 60 seconds per point (acupuncture group) and the other will receive the standard care with orally administered glucose solution (glucose group). The complete procedure of blood sampling will be recorded on video, excluding the intervention before heel lance. A paediatric nurse, blinded with respect to the allocation, will evaluate these video recordings and determine the Premature Infant Pain Profile (PIPP) for each neonate. Primary outcome will be the mean difference in PIPP scores between groups.

Discussion

This observer-blinded randomised controlled trial has been designed to explore potential advantages of laser acupuncture in the management of neonatal pain because more data are required to provide information about its efficacy and safety.

Trial Registration

This trial is registered with DRKS00010122.

Detecting autonomic response to pain in Rett syndrome

OBJECTIVE

To quantify pain response in girls affected by Rett syndrome (RTT) using electrodermal activity (EDA), a measure of skin conductance, reflecting sympathetic activity known to be modulated by physical and environmental stress.

METHODS

EDA increase, heart rate (HR) increase and Face Legs Activity Cry Consolability (FLACC) values calculated during venipuncture (invasive) and vital signs collection (non-invasive) events were compared with values calculated during a prior baseline and a RTT clinical severity score (CSS).

RESULTS

EDA and HR increase were significantly higher than baseline during venipuncture only and not significantly correlated with FLACC or CSS. EDA increase was the most sensitive measure of pain response.

CONCLUSIONS

These preliminary findings revealed that motor impairment might bias non-verbal pain scales, underscore the importance of using autonomic measures when assessing pain and warrant further investigation into the utility of using EDA to objectively quantify RTT pain response to inform future RTT pain management.

A feasibility and efficacy randomised controlled trial of swaddling for controlling procedural pain in preterm infants

AIMS AND OBJECTIVES

This study aimed to investigate the feasibility and efficacy of swaddling to control procedural pain among preterm infants.

BACKGROUND

Swaddling has been recommended for controlling neonatal pain. However, the feasibility for use is uncertain and insufficient evidence is available among preterm infants.

DESIGN

A two-arm randomised controlled trial with repeated measures.

METHOD

The study was conducted in a 21-bed neonatal intensive care unit of a regional hospital in Hong Kong. Preterm infants who required heelstick procedure were eligible. Fifty-four preterm infants between 30-37 gestational weeks were randomly assigned to swaddling (n = 27) and control (standard care, n = 27) groups. Pain assessment was performed pre, during, immediate, two, four, six and eight minutes after heelstick procedure using the Premature Infant Pain Profile.

RESULTS

The mean Premature Infant Pain Profile scores were significantly reduced in the intervention group compared to the control group during, immediate, two, four, and six minutes after the heelstick procedure. The mean changes of heart rate and oxygen saturation in the intervention group were significantly lower than that of the control group at all measured time points. Notably, the swaddled infants quickly resumed to the baseline level at two minutes whereas the control group reached the stable state at an extended period of six minutes.

CONCLUSION

The findings show that swaddling is feasible and efficacious in controlling pain for heelstick procedure among preterm infants. No adverse effects were observed.

RELEVANCE TO CLINICAL PRACTICE

This article presents the feasibility and efficacy of swaddling as a non-pharmacological and non-invasive intervention to relieve pain during the heelstick procedures among preterm infants. Swaddling can contribute to control minor procedural pain in neonates as one of the simple, safe, cost effective, humanistic and natural analgesia alternatives.

Neonatal inflammatory pain and systemic inflammatory responses as possible environmental factors in the development of autism spectrum disorder of juvenile rats

Background

Autism spectrum disorder (ASD) affects many children and juveniles. The pathogenesis of ASD is not well understood. Environmental factors may play important roles in the development of ASD. We examined a possible relationship of inflammatory pain in neonates and the development of ASD in juveniles.

Methods

Acute inflammation pain was induced by 5 % formalin (5 μl/day) subcutaneous injection into two hindpaws of postnatal day 3 to 5 (P3–P5) rat pups. Western blot, immunohistochemical, and behavioral examinations were performed at different time points after the insult.

Results

Formalin injection caused acute and chronic inflammatory responses including transient local edema, increased levels of inflammatory cytokines, TNF-α, and IL-1β in the blood as well as in the brain, and increased microglia in the brain. One day after the pain insult, there was significant cell death in the cortex and hippocampus. Two weeks later, although the hindpaw local reaction subsided, impaired axonal growth and demyelization were seen in the brain of P21 juvenile rats. The number of bromodeoxyuridine (BrdU) and doublecortin (DCX) double-positive cells in the hippocampal dentate gyrus of P21 rats was significantly lower than that in controls, indicating reduced neurogenesis. In the P21 rat’s brain of the formalin group, the expression of autism-related gene neurexin 1 (NRXN1), fragile X mental retardation 1 (FMR1), and oxytocin was significantly downregulated, consistent with the gene alteration in ASD. Juvenile rats in the formalin group showed hyperalgesia, repetitive behaviors, abnormal locomotion, sleep disorder, and distinct deficits in social memory and social activities. These alterations in neuroinflammatory reactions, gene expression, and behaviors were more evident in male than in female rats. Importantly, an anti-inflammation treatment using indomethacin (10 mg/kg, i.p.) at the time of formalin injections suppressed inflammatory responses and neuronal cell death and prevented alterations in ASD-related genes and the development of abnormal behaviors.

Conclusions

These novel observations indicate that severe inflammatory pain in neonates and persistent inflammatory reactions may predispose premature infants to development delays and psychiatric disorders including ASD. The prevention of pain stimuli and prompt treatments of inflammation during development appear vitally important in disrupting possible evolution of ASD syndromes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-016-0575-x) contains supplementary material, which is available to authorized users.

Pain-Related Reactions among Premature Infants with Gestational Age Less than 26 Weeks: An Observational Cohort Study

INTRODUCTION

There is insufficient information regarding acute pain reactions among premature infants with a gestational age of less than 26 weeks and no appropriate scale for pain measurement in this age group. We hypothesized that these infants present specific reactions to a standardized pain stimulus within the first 3 days of life.

METHODOLOGY

Mixed-methods, prospective, open-label, single-arm, observational study. Routine capillary or peripheral blood takes were filmed. The model consisting of a baseline, a preparatory, an interventional and a return-to-baseline phase was filmed. After a pilot evaluation, experienced medical and nursing neonatal intensive care unit (NICU) staff analysed the videos.

RESULTS

Twenty infants with gestational ages ranging from 22 weeks and 3 days to 26 weeks (mean 24 weeks) were recruited. Nineteen infants showed pain reactions, with a mean latency of 8.3 s (range 2-30). The majority presented eye movements, changes of the breath pattern and a slight increase in the mean SpO2 value. A high degree of interrater and intrarater reliability was found.

DISCUSSION

Premature infants with a gestational age of up to 26 weeks can present a variety of discrete reactions as response to a pain stimulus within the first 72 h of life. Experienced NICU staff can perform a valid and reliable evaluation of these reactions.

Care-related pain in hospitalized patients: severity and patient perception of management

BACKGROUND

Hospitalized patients commonly undergo painful procedures, but little is known about care-related pain (CRP) in the overall population of inpatients. We conducted a cross-sectional 1-day survey to assess the prevalence and characteristics of CRP and its management in all units of a university hospital in Paris and determined the factors linked to severe CRP.

METHODS

All patients who were able to communicate and were hospitalized for at least 24 h but not in a day-care or neonatal unit were included.

RESULTS

From 938 patients who completed the questionnaire, 554 patients reported pain within the previous 24 h, for a 59% prevalence of pain, and 540 (58%) had experienced CRP in the previous 15 days (51% males; mean [SD] age 54 [18] years). Of 907 procedures, 330 (37%) resulted in severe pain. The most-often reported painful procedures were vascular punctures and patient mobilization. Severe CRP was associated with long hospitalization; non-vascular invasive punctures, catheterization, mobilization or radiological examination; or pain during the previous 24 h due to surgery or treatment. Only half of the patients declared that they had received information regarding the painful procedure. Treatment for pain was proposed and delivered in less than one quarter of cases.

CONCLUSIONS

Our results of a survey of pain management in hospitalized patients relate to a wide variety of medical conditions and procedures. Health-care workers should be more systematic in managing CRP, and attention should be paid to patients at greatest risk of severe CRP.

Local anesthetic wound infusion versus standard analgesia in paediatric post-operative pain control

INTRODUCTION

Local anesthetic wound infusion has shown promising results in adults. Its use in children is limited to some centers and there are only a few prospective trials in this group of patients.

METHODS

Sub-fascial continuous local anaesthetic wound infusion (CLAWI) (0.2% Bupivacaine) plus intravenous paracetamol and rescue intravenous morphine was compared to: (a) Epidural bupivacaine (EPI) plus paracetamol and rescue intravenous morphine for patients undergoing laparotomy. (b) Intravenous morphine and paracetamol (standard post-operative analgesia-SAPA) in children undergoing Lanz incision laparotomy for complicated appendicitis. 'InfiltralLong', PANJUNK(®) catheters were placed sub-fascially after peritoneal closure for post-operative bupivacaine infusion. Pain scores were recorded regularly by the same blinded pain specialist. The primary outcomes were pain control and total morphine. The secondary outcomes were time to full feeds, mobilization requirement for urinary catheter and complications.

RESULTS

Sixty patients (18 laparotomy-CLAWI, 17 laparotomy-EPI and 12 appendectomy-CLAWI, and 13 appendectomy-SAPA) were analyzed. The average pain score was 2.5 (1-4) in the CLAWI groups, 3.0 (1-5) in the EPI group and 3.5 (2-5) in the SAPA group. Morphine requirements were markedly less for CLAWI. SAPA and EPI groups required urinary catheters for longer and took longer to mobilize (average 4 days compared to 2 days for CLAWI). There were no wound or bupivacaine complications in the CLAWI group.

CONCLUSION

Continuous subfascial bupivacaine infusion is reliable, safe and effective in paediatric post-operative pain control with considerably reduced opiate requirements.

Early postnatal nociceptive stimulation results in deficits of spatial memory in male rats

Prematurely-born infants are exposed to multiple invasive procedures while in the intensive care unit. Newborn rats and humans have similar behavioral responses to noxious stimulation. Previous studies have shown that early noxious stimuli may alter dentate gyrus neurogenesis and the behavioral repertoire of adult rats. We evaluated the late effects of noxious stimulation administered during different phases of development on two spatial memory tests; object recognition (OR) and Morris water maze (WM) tests. Noxious stimulation was induced by an intra-plantar injection of complete Freund's adjuvant (CFA) on postnatal (P) day 1 (group P1) or 8 (P8). Control animals were not stimulated. Behavioral tests were conducted on P60 in both male and female animals. In the WM, three domains were evaluated: acquisition, probe trial performance and reversal re-acquisition. The number of Nissl stained cells in the dentate granule cell layer was assessed by stereological counting. The OR test revealed that P1 male rats had poor long-term memory compared to the control and P8 groups. In the WM, no short- or long-term memory differences were detected between early postnatal-stimulated male and female rats and their respective controls. However, the ability to find the hidden platform in a new position was reduced in P1 male rats. The number of dentate granule cells in P8 males was higher than in all other groups. This study demonstrates that noxious stimulation on P1 results in spatial learning deficits in male animals, but does not disrupt the development of the hippocampus-dependent strategies of learning and memory.

Sleep deprivation, pain and prematurity: a review study

The aim was to describe current reports in the scientific literature on sleep in the intensive care environment and sleep deprivation associated with painful experiences in premature infant. A systematic search was conducted for studies on sleep, pain, premature birth and care of the newborn. Web of Knowledge, MEDLINE, LILACS, Cochrane Library, PubMed, EMBASE, Scopus, VHL and SciELO databases were consulted. The association between sleep deprivation and pain generates effects that are observed in the brain and the behavioral and physiological activity of preterm infants. Polysomnography in intensive care units and pain management in neonates allow comparison with the first year of life and term infants. We have found few references and evidence that neonatal care programs can influence sleep development and reduce the negative impact of the environment. This evidence is discussed from the perspective of how hospital intervention can improve the development of premature infants.

Early repetitive pain in preterm infants in relation to the developing brain

Infants born preterm (<37 weeks of gestation) are particularly vulnerable to procedural stress and pain exposure during neonatal intensive care, at a time of rapid and complex brain development. Concerns regarding effects of neonatal pain on brain development have long been expressed. However, empirical evidence of adverse associations is relatively recent. Thus, many questions remain to be answered. This review discusses the short- and long-term effects of pain-related stress and associated treatments on brain maturation and neurodevelopmental outcomes in children born preterm. The current state of the evidence is presented and future research directions are proposed.

Neonatal pain: What's age got to do with it?

Background:

The neurobiology of neonatal pain processing, especially in preterm infants, differs significantly from older infants, children, adolescence, and adults. Research suggests that strong painful procedures or repeated mild procedures may permanently modify individual pain processing. Acute injuries at critical developmental periods are risk factors for persistent altered neurodevelopment. The purpose of this narrative review is to present the seminal and current literature describing the unique physiological aspects of neonatal pain processing.

Methods:

Articles describing the structures and physiological processes that influence neonatal pain were identified from electronic databases Medline, PubMed, and CINAHL.

Results:

The representation of neonatal pain physiology is described in three processes: Local peripheral nervous system processes, referred to as transduction; spinal cord processing, referred to as transmission and modulation; and supraspinal processing and integration or perception of pain. The consequences of undermanaged pain in preterm infants and neonates are discussed.

Conclusion:

Although the process and pain responses in neonates bear some similarity to processes and pain responses in older infants, children, adolescence, and adults; there are some pain processes and responses that are unique to neonates rendering them at risk for inadequate pain treatment. Moreover, exposure to repeated painful stimuli contributes to adverse long-term physiologic and behavioral sequelae. With the emergence of studies showing that painful experiences are capable of rewiring the adult brain, it is imperative that we treat neonatal pain effectively.

Behaviour problems and cortisol levels in very-low-birth-weight children

Abstract Background. There are still diverging results concerning the behaviour of children with very-low-birth-weight (VLBW) and they have been questioned to display different levels of stress hormone than normal-birth-weight (NBW) children. Aims. This study examined behaviour and the stress hormone cortisol in children with VLBW at the ages of 7 and 9 years compared with children with NBW. Results. Fifty-one VLBW and 50 NBW children were studied with the Child Behavior Checklist. Cortisol rhythm was measured through saliva samples three times a day for 2 days. VLBW children displayed more behavioural problems than NBW children, specifically social and attention problems, although still within normal ranges. They showed lower cortisol levels both at 7 and 9 years of age. No strong association between behaviour and cortisol levels was shown. Conclusion. VLBW children display more behaviour problems compared with NBW children but both groups score are within the normal range. Down-regulation of their hypothalamic-pituitary-adrenal (HPA) function in terms of lower cortisol levels is also noted.

The use of ultrasound-guided regional anaesthetic techniques in neonates and young infants

Optimal pain therapy during the perioperative period or at the neonatal intensive care unit and subsequent reduced use of opioids and various sedative drugs is an important factor for patients care. The use of various regional anaesthetic techniques in experienced hands provides excellent pain relief and has the potency to reduce the requirement for perioperative mechanical ventilation. Most of regional anaesthesia techniques are applicable also in neonates and young infants and can be used in an effective and safe manner. Ultrasound guidance should be used for all regional anaesthetic techniques to increase efficacy and safety. The spectrum of indications for ultrasound-guided regional anaesthesia in babies and infants are surgery, selective pain therapy and sympathicolysis. This review reflects an expert-based description of the most recent developments in ultrasound-guided regional anaesthetic techniques in babies and infants.

Does daily kangaroo care provide sustained pain and stress relief in preterm infants?

OBJECTIVES

1. Determine whether stress in preterm infants, measured with salivary cortisol, decreases after five days of Kangaroo Care (KC) compared to five days of Standard Care (SC). 2. To determine whether kangaroo care provides sustainable pain relief beyond the period of skin-to-skin holding.

STUDY DESIGN

Preterm infants (n = 38) born at 27-30 weeks gestational age were randomized to either the KC or the SC group and received the allocated intervention starting on day of life (DOL) five and continuing for five days. Salivary cortisol was collected on DOL five and again on DOL ten. Differences were analyzed using repeated measures ANOVA and t tests. Pain during nasal suctioning over five days was assessed using the Premature Infant Pain Profile (PIPP).

RESULT

1. Adequate saliva samples for salivary cortisol were collected for 13 KC infants and 11 SC infants. There was no main effect of group (p = 0.49), but there was a significant main effect of age (DOL five versus DOL ten), with salivary cortisol levels decreasing in both groups (p = 0.02). 2. Pain scores for both groups (n = 38) indicted mild to moderate pain during suctioning, with no significant difference in pain scores between groups.

CONCLUSION

1. KC did not affect salivary cortisol levels in preterm neonates, but levels in both the KC and SC groups decreased over time from DOL five to ten. Salivary cortisol may vary with age of infant. 2. Infants experience pain during routine suctioning and may require pain management.

Behavioral effects of perinatal opioid exposure

Opioids are among the world's oldest known drugs used mostly for pain relief, but recreational use is also widespread. A particularly important problem is opioid exposure in females, as their offspring can also be affected. Adverse intrauterine and postnatal environments can affect offspring development and may lead to various disabilities later in life. It is clear that repetitive painful experiences, such as randomly occurring invasive procedures during neonatal intensive care, can permanently alter neuronal and synaptic organization and therefore later behavior. At the same time, analgesic drugs can also be harmful, inducing neuronal apoptosis or withdrawal symptoms in the neonate and behavioral alterations in adulthood. Hence, risk-benefit ratios should be taken into consideration when pain relief is required during pregnancy or in neonates. Recreational use of opioids can also alter many aspects of life. Intrauterine opioid exposure has many toxic effects, inducing poor pregnancy outcomes due to underdevelopment, but it is believed that later negative consequences are more related to environmental factors such as a chaotic lifestyle and inadequate prenatal care. One of the crucial components is maternal care, which changes profoundly in addicted mothers. In substance-dependent mothers, pre- and postnatal care has special importance, and controlled treatment with a synthetic opioid (e.g., methadone) could be beneficial. We aimed to summarize and compare human and rodent data, as it is important to close the gap between scientific knowledge and societal policies. Special emphasis is given to gender differences in the sensitivity of offspring to perinatal opioid exposure.

Early-life stress impacts the developing hippocampus and primes seizure occurrence: cellular, molecular, and epigenetic mechanisms

Early-life stress includes prenatal, postnatal, and adolescence stress. Early-life stress can affect the development of the hypothalamic-pituitary-adrenal (HPA) axis, and cause cellular and molecular changes in the developing hippocampus that can result in neurobehavioral changes later in life. Epidemiological data implicate stress as a cause of seizures in both children and adults. Emerging evidence indicates that both prenatal and postnatal stress can prime the developing brain for seizures and an increase in epileptogenesis. This article reviews the cellular and molecular changes encountered during prenatal and postnatal stress, and assesses the possible link between these changes and increases in seizure occurrence and epileptogenesis in the developing hippocampus. In addititon, the priming effect of prenatal and postnatal stress for seizures and epileptogenesis is discussed. Finally, the roles of epigenetic modifications in hippocampus and HPA axis programming, early-life stress, and epilepsy are discussed.

Pain assessment and measurement in neonates: an updated review

Pain assessment and measurement are the cornerstones of pain management. Pain assessment connotes a comprehensive multidimensional description. Conversely, pain measurement provides a numeric quantitative description of each factor illustrating pain qualities. Pain scales provide a composite score used to guide practice and research. The type of infant pain instrument chosen is a significant factor in guiding pain management practice. The purpose of this review was to summarize current infant pain measures by introducing a conceptual framework for pain measurement. Although more than 40 infant pain instruments exist, many were devised solely for research purposes; several of the newly developed instruments largely overlap with existing instruments. Integration of pain management into daily practice remains problematic. Understanding how each instrument measures infant pain allows clinicians to make better decisions about what instrument to use with which infant and in what circumstances. In addition, novel new measurement techniques need further testing.

Sex-related long-term behavioral and hippocampal cellular alterations after nociceptive stimulation throughout postnatal development in rats

Early noxious stimuli may alter the neurogenesis rate in the dentate gyrus and the behavioral repertoire of adult rats. This study evaluated the long-term effects of noxious stimulation, imposed in different phases of development, on nociceptive and anxiety-like behaviors, hippocampal activation, cell proliferation, hippocampal BDNF and plasma corticosterone levels in 40 day-old male and female adolescents. Noxious stimulation was induced by intra-plantar injection of Complete Freund's adjuvant (CFA), on postnatal days (P) 1 (group P1), 8 (P8) or 21 (P21). Control animals were not stimulated in any way. On P21 a subset of animals from each group received BrdU and was perfused on P40 for identification of proliferating cells in the granule cell layer of the dentate gyrus. Another subset of rats was subjected to behavioral testing on P40 and one week later, to magnetic resonance imaging (MRI) acquisition. Noxious stimulation evoked hypoalgesia in adolescents, mainly in females (P < 0.02), reflected by greater latency to withdraw the paw and less paw lickings in the hot plate test than controls (P < 0.001). It also resulted in more time spent in the open arms, e.g., less anxiety-like behavior than controls (P < 0.01), especially in females (P < 0.01, compared with males). Proliferative cell rate in the dentate gyrus was the highest in P8 males and females (P < 0.001), with males exhibiting more proliferation than females on P1 and P8, which was directly related to the hippocampal levels of BDNF and inversely related to plasma corticosterone. Sex differences were also detected in manganese-enhanced MRI signal, which was more prominent in P1 females than males (P < 0.01). This study represents the first step of investigation on the cellular basis of the sex-dependent long-term consequences of nociceptive stimuli in newborns.

Neonatal pain-related stress predicts cortical thickness at age 7 years in children born very preterm

Background

Altered brain development is evident in children born very preterm (24–32 weeks gestational age), including reduction in gray and white matter volumes, and thinner cortex, from infancy to adolescence compared to term-born peers. However, many questions remain regarding the etiology. Infants born very preterm are exposed to repeated procedural pain-related stress during a period of very rapid brain development. In this vulnerable population, we have previously found that neonatal pain-related stress is associated with atypical brain development from birth to term-equivalent age. Our present aim was to evaluate whether neonatal pain-related stress (adjusted for clinical confounders of prematurity) is associated with altered cortical thickness in very preterm children at school age.

Methods

42 right-handed children born very preterm (24–32 weeks gestational age) followed longitudinally from birth underwent 3-D T1 MRI neuroimaging at mean age 7.9 yrs. Children with severe brain injury and major motor/sensory/cognitive impairment were excluded. Regional cortical thickness was calculated using custom developed software utilizing FreeSurfer segmentation data. The association between neonatal pain-related stress (defined as the number of skin-breaking procedures) accounting for clinical confounders (gestational age, illness severity, infection, mechanical ventilation, surgeries, and morphine exposure), was examined in relation to cortical thickness using constrained principal component analysis followed by generalized linear modeling.

Results

After correcting for multiple comparisons and adjusting for neonatal clinical factors, greater neonatal pain-related stress was associated with significantly thinner cortex in 21/66 cerebral regions (p-values ranged from 0.00001 to 0.014), predominately in the frontal and parietal lobes.

Conclusions

In very preterm children without major sensory, motor or cognitive impairments, neonatal pain-related stress appears to be associated with thinner cortex in multiple regions at school age, independent of other neonatal risk factors.

Neonatal nurses' perceptions of pain assessment and management in NICUs: a national survey

PURPOSE

The purpose of this survey was to investigate neonatal nurses' perceptions of knowledge and practice in pain assessment and management.

METHODS

A convenience sample consisted of 237 neonatal nurses with a membership in National Association of Neonatal Nurses (NANN) and neonatal nurses in Connecticut who were not NANN members. A researcher-developed questionnaire, including 36 questions with Likert scale and 2 open-ended questions, was used.

RESULTS

The nurses were knowledgeable, and about 50% felt that they received adequate training and continuing education on pain. Participants reported the use of pain assessment tools (81%) and felt confident in uses of pharmacologic (83%) and nonpharmacologic interventions (79%). More than half felt that the pain tool used in their unit was appropriate for neonates (65%) and was an accurate measure (60%). Fewer than half reported that pain was well managed (44%) and that their pain protocols were research evidence based (43%).

CONCLUSIONS

Nurses' perceptions of well-managed pain were significantly correlated with training, use of appropriate and accurate pain tools, and clear and research-based protocols. Barriers to effective pain management emerged as resistance to change, lack of knowledge, perceived fear of side effects of pain medication and incorrect interpretation of pain signals, lack of time, and lack of trust in the pain assessment tools. Gaps exist in knowledge, evidence, and practice in neonatal assessment and management.

Safety of Noninvasive Electrical Stimulation of Acupuncture Points During a Routine Neonatal Heel Stick

BACKGROUND

Hospitalized infants may undergo frequent painful procedures with inadequate pain relief. Alternative pain relief interventions are needed.

OBJECTIVE

The aim of this research was to determine the safety of noninvasive electrical stimulation of acupuncture points (NESAP) in neonates who were receiving routine heel sticks.

DESIGN

This was a descriptive study performed to assess the safety of using a transcutaneous electrical nerve stimulation (TENS) unit to deliver NESAP to neonates.

SETTING/SUBJECTS

The subjects were healthy newborn infants<3 days old before hospital discharge.

INTERVENTION

The intervention was NESAP delivered via a TENS unit, administered before, during, and after heel stick. The electrodes of the TENS unit were applied at four acupuncture points. Settings were gradually increased: 6 infants received 1.0 mA, 2 Hz; the second 6 infants received 2.0 mA, 10 Hz; and the last 18 infants received 3.5 mA, 10 Hz.

MAIN OUTCOME MEASURES

THREE MAIN MEASURES WERE USED: (1) skin assessment (2) vital signs; (3) pain scores using the Premature Infant Pain Profile (PIPP).

RESULTS

There were no significant changes in vital signs during and after NESAP. There were no changes in PIPP scores in the first 12 infants after initiation of NESAP. A slight but nonsignificant increase in PIPP scores (from 2.65 to 3.5 on a scale of 0-18) occurred in the last 18 infants. There were no adverse events during or after NESAP.

CONCLUSIONS

NESAP is safe for infants with low settings on a TENS unit.

Effect of Kangaroo mother care in reducing pain due to heel prick among preterm neonates: a crossover trial

BACKGROUND

Preterm neonates undergo several painful procedures in NICU including heel prick for blood sugar monitoring. Nonpharmacological interventions have been tried to decrease this procedural pain. There are only few studies on Kangaroo mother care (KMC) in reducing pain among preterm neonates.

METHOD

This crossover trial was conducted at a tertiary care teaching hospital in south India. Premature Infant Pain Profile (PIPP) related to heel prick was assessed in 50 preterm neonates undergoing KMC and compared with 50 preterm babies without KMC.

RESULTS

PIPP scores at 15 minutes and 30 minutes after heel prick were significantly less in KMC group compared to control group. Mean PIPP difference between baseline and 30 minutes after heel prick was also significantly low in KMC group compared to control group.

CONCLUSION

KMC is effective in reducing pain due to heel prick among preterm babies.