Intervention minimizing preterm infants' exposure to NICU light and noise

Defining the Concept of Acoustic Neuroprotection in the Neonate: A Concept Analysis

BACKGROUND

It has long been understood and acknowledged that the Neonatal Intensive Care Unit (NICU) environment and the transport environments are extremely loud, with both long- and short-term sequelae to the neonate, being well over the recommended amount of noise by the American Academy of Pediatrics (AAP). This problem has yet to be properly addressed. The purpose of this manuscript is to define and explain the concept of acoustic neuroprotection. While we cannot change the internal structures of the neonates' auditory system, we could change the acoustics of the environment to be support neuroprotection of these sensitive patients.

EVIDENCE ACQUISITION

Walker and Avant's concept analysis steps were followed to create and define the idea of acoustic neuroprotection, as it has not had a definition before. A total of 45 articles from multiple search engines were chosen. A combination of 2 concepts were used: acoustic protection and neurodevelopmental protection/support. The search was expanded past 20 years for lack of research and importance of seminal works.

RESULTS

To achieve acoustic neuroprotection, a neonate should not be exposed to sound greater than 45 decibels (dBa) for longer than 10 s, and exposure to sound above 80 dBa should never occur. Appropriate interventions need to include supporting the neurodevelopment of the neonate through therapeutic sound, while decreasing the amount of toxic noise exposure to safe levels.

IMPLICATIONS FOR PRACTICE AND RESEARCH

By further understanding and having a quantifiable goal of acoustic neuroprotection for neonates, neonatal clinicians can work together to create new interventions for how to better protect and support the care of our tiniest patients.

Noise or sound management in the neonatal intensive care unit for preterm or very low birth weight infants

BACKGROUND

Infants in the neonatal intensive care unit (NICU) are subjected to different types of stress, including sounds of high intensity. The sound levels in NICUs often exceed the maximum acceptable level recommended by the American Academy of Pediatrics, which is 45 decibels (dB). Hearing impairment is diagnosed in 2% to 10% of preterm infants compared to only 0.1% of the general paediatric population. Bringing sound levels under 45 dB can be achieved by lowering the sound levels in an entire unit; by treating the infant in a section of a NICU, in a 'private' room, or in incubators in which the sound levels are controlled; or by reducing sound levels at the individual level using earmuffs or earplugs. By lowering sound levels, the resulting stress can be diminished, thereby promoting growth and reducing adverse neonatal outcomes. This review is an update of one originally published in 2015 and first updated in 2020.

OBJECTIVES

To determine the benefits and harms of sound reduction on the growth and long-term neurodevelopmental outcomes of neonates.

SEARCH METHODS

We used standard, extensive Cochrane search methods. On 21 and 22 August 2023, a Cochrane Information Specialist searched CENTRAL, PubMed, Embase, two other databases, two trials registers, and grey literature via Google Scholar and conference abstracts from Pediatric Academic Societies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs in preterm infants (less than 32 weeks' postmenstrual age (PMA) or less than 1500 g birth weight) cared for in the resuscitation area, during transport, or once admitted to a NICU or stepdown unit. We specified three types of intervention: 1) intervention at the unit level (i.e. the entire neonatal department), 2) at the section or room level, or 3) at the individual level (e.g. hearing protection).

DATA COLLECTION AND ANALYSIS

We used the standardised review methods of Cochrane Neonatal to assess the risk of bias in the studies. We used the risk ratio (RR) and risk difference (RD), with their 95% confidence intervals (CIs), for dichotomous data. We used the mean difference (MD) for continuous data. Our primary outcome was major neurodevelopmental disability. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included one RCT, which enroled 34 newborn infants randomised to the use of silicone earplugs versus no earplugs for hearing protection. It was a single-centre study conducted at the University of Texas Medical School in Houston, Texas, USA. Earplugs were positioned at the time of randomisation and worn continuously until the infants were 35 weeks' postmenstrual age (PMA) or discharged (whichever came first). Newborns in the control group received standard care. The evidence is very uncertain about the effects of silicone earplugs on the following outcomes. • Cerebral palsy (RR 3.00, 95% CI 0.15 to 61.74)and Mental Developmental Index (MDI) (Bayley II) at 18 to 22 months' corrected age (MD 14.00, 95% CI 3.13 to 24.87); no other indicators of major neurodevelopmental disability were reported. • Normal auditory functioning at discharge (RR 1.65, 95% CI 0.93 to 2.94) • All-cause mortality during hospital stay (RR 2.07, 95% CI 0.64 to 6.70; RD 0.20, 95% CI -0.09 to 0.50) • Weight (kg) at 18 to 22 months' corrected age (MD 0.31, 95% CI -1.53 to 2.16) • Height (cm) at 18 to 22 months' corrected age (MD 2.70, 95% CI -3.13 to 8.53) • Days of assisted ventilation (MD -1.44, 95% CI -23.29 to 20.41) • Days of initial hospitalisation (MD 1.36, 95% CI -31.03 to 33.75) For all outcomes, we judged the certainty of evidence as very low. We identified one ongoing RCT that will compare the effects of reduced noise levels and cycled light on visual and neural development in preterm infants.

AUTHORS' CONCLUSIONS

No studies evaluated interventions to reduce sound levels below 45 dB across the whole neonatal unit or in a room within it. We found only one study that evaluated the benefits of sound reduction in the neonatal intensive care unit for hearing protection in preterm infants. The study compared the use of silicone earplugs versus no earplugs in newborns of very low birth weight (less than 1500 g). Considering the very small sample size, imprecise results, and high risk of attrition bias, the evidence based on this research is very uncertain and no conclusions can be drawn. As there is a lack of evidence to inform healthcare or policy decisions, large, well designed, well conducted, and fully reported RCTs that analyse different aspects of noise reduction in NICUs are needed. They should report both short- and long-term outcomes.

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents

Noise exposure is a major cause of hearing loss in adults. Yet, noise affects people of all ages, and noise-induced hearing loss is also a problem for young people. Sensorineural hearing loss caused by noise and other toxic exposures is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, and quality of life. Children and adolescents have unique vulnerabilities to noise. Children may be exposed beginning in NICUs and well-baby nurseries, at home, at school, in their neighborhoods, and in recreational settings. Personal listening devices are increasingly used, even by small children. Infants and young children cannot remove themselves from noisy situations and must rely on adults to do so, children may not recognize hazardous noise exposures, and teenagers generally do not understand the consequences of high exposure to music from personal listening devices or attending concerts and dances. Environmental noise exposure has disproportionate effects on underserved communities. In this report and the accompanying policy statement, common sources of noise and effects on hearing at different life stages are reviewed. Noise-abatement interventions in various settings are discussed. Because noise exposure often starts in infancy and its effects result mainly from cumulative exposure to loud noise over long periods of time, more attention is needed to its presence in everyday activities starting early in life. Listening to music and attending dances, concerts, and celebratory and other events are sources of joy, pleasure, and relaxation for many people. These situations, however, often result in potentially harmful noise exposures. Pediatricians can potentially lessen exposures, including promotion of safer listening, by raising awareness in parents, children, and teenagers. Noise exposure is underrecognized as a serious public health issue in the United States, with exposure limits enforceable only in workplaces and not for the general public, including children and adolescents. Greater awareness of noise hazards is needed at a societal level.

The Effect of Incubator Cover on Newborn Vital Signs: The Design of Repeated Measurements in Two Separate Groups with No Control Group

(1) Background: During their stays in neonatal intensive care units (NICU), newborns are exposed to many stimuli that disrupt their physiological indicators. The aim of this study was to investigate the impact of the light-dark cycle created with and without an incubator cover on the vital signs of term and preterm newborns. (2) Methods: A repeated measures design was used in the study utilizing two separate groups, without a control group. The study included 91 neonates hospitalized in a NICU (44 term and 47 preterm). With and without an incubator cover, the newborns' vital signs (heart rate (HR), respiratory rate (RR), oxygen saturation (SpO₂), and body temperature (BT)) were measured. Three separate measurements were taken. (3) Results: The mean age of the newborns was 37.0 weeks. There was no significant difference between the HR and RR medians of the term and preterms in the incubator undraped and clad measurements (p > 0.05). At the first measurement, the SpO₂ medians of the incubator-covered term and preterms were significantly higher than those of the incubator-covered term and preterms (p = 0.001). (4) Conclusions: The vital signs of the neonates demonstrated variable responses in the measurements when their incubators were covered vs. when they were not covered. However, more research on the effect of the light-dark cycle on their vital signs is required.

Envisioning translational hyperscanning: how applied neuroscience might improve family-centered care

From the very beginning of their life, human beings are immersed in a social and interactive environment that contributes to shaping their social and cognitive development under typical and at-risk conditions. In order to understand human development in its bidirectional relationship with the social environment, we need to develop a 'complexity-sensitive' approach in neuroscience. Recent advances have started to do so with the application of hyperscanning techniques which involve recording adult and child neural activity simultaneously and highlighting the presence of similar patterns of brain activity in the dyad. Numerous studies focused on typically developing children have been published in recent years with the application of this technique to different fields of developmental research. However, hyperscanning techniques could also be extremely beneficial and effective in studying development in atypical and clinical populations. Such application, namely translational hyperscanning, should foster the transition toward a two-brain translational neuroscience. In this paper, we envision how the application of hyperscanning to atypical and clinical child populations can inform family-centered care for children and their parents.

Music Therapy Intervention in an Open Bay Neonatal Intensive Care Unit Room Is Associated with Less Noise and Higher Signal to Noise Ratios: A Case-Control Study

BACKGROUND

Noise reduction in the Neonatal Intensive Care Unit (NICU) is important for neurodevelopment, but the impact of music therapy on noise is not yet known.

OBJECTIVE

To investigate the effect of music therapy (MT) on noise levels, and whether individual MT (IMT) or environmental MT (EMT) increases meaningful signal-to-noise ratios (SNR).

STUDY DESIGN

This case-control study was conducted in a level III NICU. Noise levels were recorded simultaneously from two open bay rooms, with a maximum of 10 infants in each room: one with MT and the other without. MT sessions were carried out for approximately 45 min with either IMT or EMT, implemented according to the Rhythm Breath and Lullaby principles. Noise production data were recorded for 4 h on 26 occasions of EMT and IMT, and analyzed using R version 4.0.2 software.

RESULTS

Overall average equivalent continuous noise levels (Leq) were lower in the room with MT as compared to the room without MT (53.1 (3.6) vs. 61.4 (4.7) dBA, p = 0.02, d = 2.1 (CI, 0.82, 3.42). IMT was associated with lower overall Leq levels as compared to EMT (51.2 vs. 56.5 dBA, p = 0.04, d = 1.6 (CI, 0.53, 1.97). The lowest sound levels with MT occurred approximately 60 min after the MT started (46 ± 3.9 dBA), with a gradual increase during the remaining recording time, but still significantly lower compared to the room without MT. The SNR was higher (18.1 vs. 10.3 dBA, p = 0.01, d = 2.8 (CI, 1.3, 3.86)) in the room with MT than in the room without MT.

CONCLUSION

Integrating MT modalities such as IMT and EMT in an open bay NICU room helps reduce noise. Both MT modalities resulted in higher SNR compared to the control room, which may indicate that they are meaningful for the neurodevelopment of preterm infants.

Neonatal heart rate variability: a contemporary scoping review of analysis methods and clinical applications

BACKGROUND

Neonatal heart rate variability (HRV) is widely used as a research tool. However, HRV calculation methods are highly variable making it difficult for comparisons between studies.

OBJECTIVES

To describe the different types of investigations where neonatal HRV was used, study characteristics, and types of analyses performed.

ELIGIBILITY CRITERIA

Human neonates ≤1 month of corrected age.

SOURCES OF EVIDENCE

A protocol and search strategy of the literature was developed in collaboration with the McGill University Health Center's librarians and articles were obtained from searches in the Biosis, Cochrane, Embase, Medline and Web of Science databases published between 1 January 2000 and 1 July 2020.

CHARTING METHODS

A single reviewer screened for eligibility and data were extracted from the included articles. Information collected included the study characteristics and population, type of HRV analysis used (time domain, frequency domain, non-linear, heart rate characteristics (HRC) parameters) and clinical applications (physiological and pathological conditions, responses to various stimuli and outcome prediction).

RESULTS

Of the 286 articles included, 171 (60%) were small single centre studies (sample size <50) performed on term infants (n=136). There were 138 different types of investigations reported: physiological investigations (n=162), responses to various stimuli (n=136), pathological conditions (n=109) and outcome predictor (n=30). Frequency domain analyses were used in 210 articles (73%), followed by time domain (n=139), non-linear methods (n=74) or HRC analyses (n=25). Additionally, over 60 different measures of HRV were reported; in the frequency domain analyses alone there were 29 different ranges used for the low frequency band and 46 for the high frequency band.

CONCLUSIONS

Neonatal HRV has been used in diverse types of investigations with significant lack of consistency in analysis methods applied. Specific guidelines for HRV analyses in neonates are needed to allow for comparisons between studies.

A Review on the Vagus Nerve and Autonomic Nervous System During Fetal Development: Searching for Critical Windows

The autonomic nervous system (ANS) is one of the main biological systems that regulates the body's physiology. Autonomic nervous system regulatory capacity begins before birth as the sympathetic and parasympathetic activity contributes significantly to the fetus' development. In particular, several studies have shown how vagus nerve is involved in many vital processes during fetal, perinatal, and postnatal life: from the regulation of inflammation through the anti-inflammatory cholinergic pathway, which may affect the functioning of each organ, to the production of hormones involved in bioenergetic metabolism. In addition, the vagus nerve has been recognized as the primary afferent pathway capable of transmitting information to the brain from every organ of the body. Therefore, this hypothesis paper aims to review the development of ANS during fetal and perinatal life, focusing particularly on the vagus nerve, to identify possible "critical windows" that could impact its maturation. These "critical windows" could help clinicians know when to monitor fetuses to effectively assess the developmental status of both ANS and specifically the vagus nerve. In addition, this paper will focus on which factors-i.e., fetal characteristics and behaviors, maternal lifestyle and pathologies, placental health and dysfunction, labor, incubator conditions, and drug exposure-may have an impact on the development of the vagus during the above-mentioned "critical window" and how. This analysis could help clinicians and stakeholders define precise guidelines for improving the management of fetuses and newborns, particularly to reduce the potential adverse environmental impacts on ANS development that may lead to persistent long-term consequences. Since the development of ANS and the vagus influence have been shown to be reflected in cardiac variability, this paper will rely in particular on studies using fetal heart rate variability (fHRV) to monitor the continued growth and health of both animal and human fetuses. In fact, fHRV is a non-invasive marker whose changes have been associated with ANS development, vagal modulation, systemic and neurological inflammatory reactions, and even fetal distress during labor.

Mothers’ experiences of neonatal intensive care: A systematic review and implications for clinical practice

BACKGROUND

Preterm birth is on the rise worldwide. Neonatal intensive care units (NICUs) have enabled many critically ill newborns to survive. When a premature baby is admitted to the NICU, the mother–infant relationship may be interrupted, affecting the mother's mental health.

AIM

To examine the maternal emotions associated with having a child in the NICU and provide suggestions for clinical practice.

METHODS

MEDLINE, CINAHL, PsychARTICLES, and PsychINFO were searched for relevant articles between 2005 to 2019, and six qualitative articles were chosen that explored the experiences of mothers who had a preterm infant in the NICU. The thematic analysis method was used to identify the most common themes.

RESULTS

Four main themes of the experience of mothers who had a preterm infant in the NICU were identified: Negative emotional impacts on the mother, support, barriers to parenting, and establishment of a loving relationship.

CONCLUSION

NICU environment is not conducive to mother-child bonding, but we stipulate steps that health care professionals can take to reduce the negative emotional toll on mothers of NICU babies.

A global perspective on parental stress in the neonatal intensive care unit: a meta-analytic study

OBJECTIVES

The Parental Stressor Scale: Neonatal Intensive Care Unit (PSS:NICU) is a well-validated tool to assess different sources of stress in parents during the NICU hospitalization of their infant. The present meta-analytic study assessed the relative impact of different NICU-related sources of parental stress in a pool of studies conducted in a wide set of different countries. Also, differences in stress levels by parent gender and country, as well as the impact of infants' neonatal characteristics and clinical conditions were explored.

METHODS

Records were searched on PubMed, Scopus, and Web of Science (January 1993-December 2019). A purposive open search string was adopted: ["PSS:NICU"] OR ["PSS-NICU"] OR ["Parental Stressor Scale"]. A multiple random-effect meta-analysis was conducted on data from 53 studies extracted by independent coders.

RESULTS

Parental role alteration emerged as the greatest source of stress for both mothers and fathers. Mothers reported higher stress levels compared to fathers. A significant difference emerged only for the subscale related to sights and sounds physical stimuli. No significant effects of infants' neonatal characteristics (gestational age, birth weight) and clinical conditions (comorbidities) emerged. A marginal positive effect of NICU length of stay emerged on the global level of parents' stress.

CONCLUSIONS

The current meta-analysis underlines that parental stress related to NICU admission is a worldwide healthcare issue. Immediate and tailored support to parents after the birth of their at-risk infant should be prioritized to reduce parental stress and to promote mothers and fathers' emotional well-being and new-born neurodevelopmental outcomes.

Heart Rate Variability in the Perinatal Period: A Critical and Conceptual Review

Neonatal intensive care units (NICUs) greatly expand the use of technology. There is a need to accurately diagnose discomfort, pain, and complications, such as sepsis, mainly before they occur. While specific treatments are possible, they are often time-consuming, invasive, or painful, with detrimental effects for the development of the infant. In the last 40 years, heart rate variability (HRV) has emerged as a non-invasive measurement to monitor newborns and infants, but it still is underused. Hence, the present paper aims to review the utility of HRV in neonatology and the instruments available to assess it, showing how HRV could be an innovative tool in the years to come. When continuously monitored, HRV could help assess the baby’s overall wellbeing and neurological development to detect stress-/pain-related behaviors or pathological conditions, such as respiratory distress syndrome and hyperbilirubinemia, to address when to perform procedures to reduce the baby’s stress/pain and interventions, such as therapeutic hypothermia, and to avoid severe complications, such as sepsis and necrotizing enterocolitis, thus reducing mortality. Based on literature and previous experiences, the first step to efficiently introduce HRV in the NICUs could consist in a monitoring system that uses photoplethysmography, which is low-cost and non-invasive, and displays one or a few metrics with good clinical utility. However, to fully harness HRV clinical potential and to greatly improve neonatal care, the monitoring systems will have to rely on modern bioinformatics (machine learning and artificial intelligence algorithms), which could easily integrate infant’s HRV metrics, vital signs, and especially past history, thus elaborating models capable to efficiently monitor and predict the infant’s clinical conditions. For this reason, hospitals and institutions will have to establish tight collaborations between the obstetric, neonatal, and pediatric departments: this way, healthcare would truly improve in every stage of the perinatal period (from conception to the first years of life), since information about patients’ health would flow freely among different professionals, and high-quality research could be performed integrating the data recorded in those departments.

A complex interprofessional intervention to improve the management of painful procedures in neonates

During hospitalization, neonates are exposed to a stressful environment and a high number of painful procedures. If pain is not treated adequately, short‐ and long‐term complications may develop. Despite evidence about neonatal pain and available guidelines, procedural pain remains undertreated. This gap between research and practice is mostly due to limited implementation of evidence‐based knowledge and time constraints. This study describes in detail the development process of a complex interprofessional intervention to improve the management of procedural pain in neonates called NEODOL© (NEOnato DOLore). The framework of the Medical Research Council (MRC) for the development and evaluation of complex interventions was used as a methodological guide for the design of the NEODOL© intervention. The development of the intervention is based on several steps and multiple methods. To report this process, we used the Criteria for Reporting the Development of Complex Interventions in Healthcare (CReDECI 2). Additionally, we evaluated the content of the intervention using a Delphi method to obtain consensus from experts, stakeholders, and parents. The complex interprofessional intervention, NEODOL©, is developed and designed for three groups: healthcare professionals, parents, and neonates for a level IIb neonatal unit at a regional hospital in southern Switzerland. A total of 16 panelists participated in the Delphi process. At the end of the Delphi process, the panelists endorsed the NEODOL© intervention as important and feasible. Following the MRC guidelines, a multimethod process was used to develop a complex interprofessional intervention to improve the management of painful procedures in newborns. Complex interprofessional interventions need theoretical bases, careful development, and integration of stakeholders to provide a comprehensive approach. The NEODOL intervention consists of promising components and has the potential to improve the management of painful procedures and should facilitate the knowledge translation into practice.

Neonatal pain: A journey spanning three decades

From 1980 into present day, 2020, the evolution of neonatal pain research is told as a journey by one researcher, Celeste Johnston. At the beginning of her work, there was essentially no interest or work in the area. She was fortunate to be led into the area by a clinical problem: how to determine the amount of pain babies in the NICU were experiencing. That question resulted in over three decades of work with neonates. Measuring pain was the first challenge and is one that remains a focus of current research. Initially, the only choices for treating pain in neonates were either opioids or anesthetics, each with problems. Research on sweet taste and more recently on skin‐to‐skin contact has offered effective and safe options for procedural pain. Although progress has been made in the incidence of pain management in infants, it still is far less than it could be. Steps along the way of measurement, treatment, and knowledge utilization are chronicled by this researcher.

Sound reduction management in the neonatal intensive care unit for preterm or very low birth weight infants

BACKGROUND

Infants in the neonatal intensive care unit (NICU) are subjected to stress, including sound of high intensity. The sound environment in the NICU is louder than most home or office environments and contains disturbing noises of short duration and at irregular intervals. There are competing auditory signals that frequently challenge preterm infants, staff and parents. The sound levels in NICUs often exceed the maximum acceptable level of 45 decibels (dB), recommended by the American Academy of Pediatrics. Hearing impairment is diagnosed in 2% to 10% of preterm infants versus 0.1% of the general paediatric population. Noise may cause apnoea, hypoxaemia, alternation in oxygen saturation, and increased oxygen consumption secondary to elevated heart and respiratory rates and may, therefore, decrease the amount of calories available for growth. Elevated levels of speech are needed to overcome the noisy environment in the NICU, thereby increasing the negative impacts on staff, newborns, and their families. High noise levels are associated with an increased rate of errors and accidents, leading to decreased performance among staff. The aim of interventions included in this review is to reduce sound levels to 45 dB or less. This can be achieved by lowering the sound levels in an entire unit, treating the infant in a section of a NICU, in a 'private' room, or in incubators in which the sound levels are controlled, or reducing the sound levels that reaches the individual infant by using earmuffs or earplugs. By lowering the sound levels that reach the neonate, the resulting stress on the cardiovascular, respiratory, neurological, and endocrine systems can be diminished, thereby promoting growth and reducing adverse neonatal outcomes.

OBJECTIVES

Primary objective To determine the effects of sound reduction on growth and long-term neurodevelopmental outcomes of neonates. Secondary objectives 1. To evaluate the effects of sound reduction on short-term medical outcomes (bronchopulmonary dysplasia, intraventricular haemorrhage, periventricular leukomalacia, retinopathy of prematurity). 2. To evaluate the effects of sound reduction on sleep patterns at three months of age. 3. To evaluate the effects of sound reduction on staff performance. 4. To evaluate the effects of sound reduction in the neonatal intensive care unit (NICU) on parents' satisfaction with the care.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library), MEDLINE, EMBASE, CINAHL, abstracts from scientific meetings, clinical trials registries (clinicaltrials.gov; controlled-trials.com; and who.int/ictrp), Pediatric Academic Societies Annual meetings 2000 to 2014 (Abstracts2ViewTM), reference lists of identified trials, and reviews to November 2014.

SELECTION CRITERIA

Preterm infants (< 32 weeks' postmenstrual age (PMA) or < 1500 g birth weight) cared for in the resuscitation area, during transport, or once admitted to a NICU or a stepdown unit.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses according to the Cochrane Neonatal Review Group.

MAIN RESULTS

One small, high quality study assessing the effects of silicone earplugs versus no earplugs qualified for inclusion. The original inclusion criteria in our protocol stipulated an age of < 48 hours at the time of initiating sound reduction. We made a deviation from our protocol and included this study in which some infants would have been > 48 hours old. There was no significant difference in weight at 34 weeks postmenstrual age (PMA): mean difference (MD) 111 g (95% confidence interval (CI) -151 to 374 g) (n = 23). There was no significant difference in weight at 18 to 22 months corrected age between the groups: MD 0.31 kg, 95% CI -1.53 to 2.16 kg (n = 14). There was a significant difference in Mental Developmental Index (Bayley II) favouring the silicone earplugs group at 18 to 22 months corrected age: MD 14.00, 95% CI 3.13 to 24.87 (n = 12), but not for Psychomotor Development Index (Bayley II) at 18 to 22 months corrected age: MD -2.16, 95% CI -18.44 to 14.12 (n =12).

AUTHORS' CONCLUSIONS

To date, only 34 infants have been enrolled in a randomised controlled trial (RCT) testing the effectiveness of reducing sound levels that reach the infants' ears in the NICU. Based on the small sample size of this single trial, we cannot make any recommendations for clinical practice. Larger, well designed, conducted and reported trials are needed.

The Effect of Earmuffs on Physiological Parameters in Preterm Infants: A Systematic Review

Noise may cause stress responses such as apnea, hypoxemia, changes in oxygen saturation and augmented oxygen consumption secondary to elevated heart and respiratory rates. Moreover, stress results in increased intracranial pressure, abnormal sleep patterns, hearing impairment, and bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular hemorrhage, periventricular leukomalacia, retardate development and alterations in the neuroendocrine system. Herein, this study aimed to discuss the effects of earmuffs on physiological parameters in preterm infants. The relevant and available peer-reviewed publications from 2012 to 2018 from various databases were analyzed. For the assessment of the studies, the full-text accessible studies were included for analysis. The retrieved documents were analyzed using VOSviewer regarding the geographical distributions of the documents with their numbers and citations, keywords proposed by the researchers. All records with the term "earmuffs OR earmuff" in the "article title, abstract, keywords" were retrieved from different databases. Accordingly, 396 documents containing the word "earmuffs OR earmuff" were recorded. The search was then restricted for publications that contain the words "noise AND nursing AND preterm" in the title and abstracts (TITLE-ABS-KEY (earmuffs OR earmuff)) AND (noise AND nursing AND preterm) (Scopus=390; Web of Science=1, Medline=2; Cochrane=1; Embase=1= Pubmed=1=n=396). After inclusion and exclusion criteria, 7 documents were recorded and then evaluated for the present study. As a conclusion, the effects of earmuffs on physiological parameters of preterm infants have not been clearly understood and reported yet. Along with the present documents, it is not clear that the use of earmuffs reduces stress and provides physiological stability in preterm infants born between approximately 28-32 weeks. The studies with a larger sample size are needed for validation of information reported in the articles analyzed herein.

NeoSTRESS: Study of Transfer and Retrieval Environmental StressorS Upon Neonates via a Smartphone Application-Light

OBJECTIVE

This study aimed to measure the light levels neonates would be exposed to during retrieval, determine whether this varied with transport mode, and compare them with recommended light exposure in neonatal intensive care units. We also aimed to determine the ease of use and acceptability of using the smartphone application.

SETTING

A neonatal retrieval service in Brisbane, Australia.

METHODS

This prospective study used the calibrated smartphone application Physics Toolbox Sensor Suite (Vieyra Software, Washington, DC). Data were collected during the outbound, nonpatient leg of 45 retrievals (25 road, 11 fixed wing aircraft, and 9 rotary aircraft journeys). Data were saved to Cloud storage and then analyzed using the PostgreSQL database.

RESULTS

The median illuminance was 6 lux (interquartile range [IQR], 1-58). The maximum recorded was 93,842 lux. The median illuminance during daytime journeys was 15 lux (IQR, 2-77). The median light level for night journeys was 1 lux (IQR, 0.5-8). Illuminance exceeded the recommended level (600 lux) for 2.1% of all journey time.

CONCLUSION

Retrieved neonates can be exposed to light in excess of recommended neonatal intensive care unit levels, including extremely bright light. It is feasible, with good staff acceptability, for a calibrated smartphone application to be used in place of a light meter.

Influence of Ear Protectors on the Sleep of Preterm Newborns: A Randomized Controlled Clinical Study

The purpose of this study was to compare the effect of ear protectors on the sleep of preterm newborns during the "quiet" times in intermediate care nursery. This was a clinical, randomized, controlled crossover study conducted in two neonatal units in São Paulo, Brazil. The sample consisted of preterm infants who met the inclusion and exclusion criteria for the study. Polysomnography and unstructured observation were used for data collection. Twenty-four preterm infants with a mean gestational age of 33.2 weeks and current weight of 1.747 g were analyzed. There was no significant difference in the total sleep time of preterm infants with and without the use of ear protectors. Newborns with lower gestational age showed a significant reduction in total sleep time with the use of ear protectors (p < .05). The use of ear protection did not increase the total sleep time for preterm infants.

Sensory exposure of neonates in single-room environments (SENSE): an observational study of light

OBJECTIVES

To measure the internal and external light exposure of incubators and open cots in an Australian single-room configured neonatal unit and compare findings to current recommendations.

METHODS

Light meters were placed in the internal and external environment of incubators and open cots within occupied single rooms in a tertiary-level neonatal unit between 15 September and 28 October 2015. Data were recorded in one-second increments over a minimum of 48 hours per room.

RESULTS

Internal median light in incubators and open cots predominantly fell below 50 lux, with low amplitude diurnal cycling. Incubator covers substantially reduced external light exposure, contributing to very low light conditions (<10 lux). Periodically, light inside incubators peaked six times greater than the maximum recommendation of 600 lux. Overall, internal incubator and open cot lighting in the neonatal unit met American Academy of Pediatrics and American College of Obstetricians and Gynecologists recommendations for 65.1% of the time during the day and 25.6% overnight. Australasian Health Infrastructure Alliance recommendations were met for 6.7% of the time during the day and 2.4% overnight.

CONCLUSIONS

Overall, light levels fell predominantly below 50 lux with peak periods of extreme light exposure. Low amplitude cyclic light was evident, but it remains unknown if this is sufficient to produce an effect on circadian entrainment, especially in preterm neonates. Current guidelines do not stipulate optimal cyclic light levels in neonatal units to promote circadian rhythms in the newborn population. Further research to determine well-defined lighting parameters for neonates of different gestations is paramount.

Rehabilitation of Infant Oral Feeding Difficulties: A Survey of Occupational Therapists Practice Approaches

This study identifies the scope of occupational therapy practice for the rehabilitation of oral feeding difficulties in infants who are in the neonatal intensive care unit (NICU). A written survey was administered to 127 occupational therapists who work with infants in the NICU. All 68 (54%) respondents used a client-centered approach, taking into consideration the infant (intrinsic), caregiver, and environmental (extrinsic) factors. Family and health team education was the most commonly provided service with the majority of occupational therapists providing services only until feeding problems were resolved. Continuing education (n = 20, 30%) and own clinical experience (n = 22, 33%) were the two most common justifications to support their choice of practice. These results suggest a client-centered approach in the rehabilitation of oral feeding difficulties is commonly used, but services are not extended beyond hospitalization. Few occupational therapists used peer-reviewed journals as sources of evidence for their practice strategies.

Sleep and salivary cortisol in preterm neonates: a clinical, randomized, controlled, crossover study

ABSTRACT Objective: Analyze the influence of ear protectors on the baseline levels of salivary cortisol and response and total sleep time of preterm neonates during two periods of environmental management of a neonatal intermediate care unit. Method: A clinical, randomized, controlled and crossover study conducted with 12 preterm neonates. The use of ear protectors was randomized in two periods. Sleep evaluation was performed using one Alice 5 Polysomnography System and unstructured observation. Results: No significant difference was observed between the baseline levels of salivary cortisol and response in preterm neonates from the control and experimental groups, and no statistical significance was observed between the total sleep time of both groups. No relationship was observed between the baseline levels of cortisol and response and total sleep time. Conclusion: Ear protectors in preterm neonates did not influence the salivary cortisol level and total sleep time in the studied periods.

Noise in the Neonatal Intensive Care Unit: What Does the Evidence Tell Us?

BACKGROUND

In 2014, more than 10% of all births in the United States were preterm (born at <37-weeks' gestation). These high-risk infants will often spend weeks to months within the neonatal intensive care unit (NICU), where noise levels can easily reach 120 decibels adjusted (dBA) on a regular and sometimes consistent basis. The American Academy of Pediatrics recommends that NICU sound levels remain below 45 dBA to promote optimal growth and development.

PURPOSE

The purpose of this evidence-based brief is to critically appraise the literature concerning preterm infant response to noise within the NICU as well as the use of noise interventions to improve health outcomes for the vulnerable preterm infant population.

METHODS/SEARCH STRATEGY

Systematic searches of databases included the Cochrane Library, CINAHL, PubMed, and Science Direct. Included studies were appraised and then synthesized into a narrative summary.

FINDINGS/RESULTS

Twenty studies met inclusion criteria for this review. While there are numerous methods that have been shown to reduce noise levels within the NICU, most NICU noise levels remain consistently above the American Academy of Pediatrics recommendations. Studies that assessed interventions found that staff reeducation was critical to sustaining appropriate noise levels.

IMPLICATIONS FOR PRACTICE

Implementing interventions with rigorous attention to initial and continued staff education with engagement and ownership is recommended. This review identifies gaps in intervention studies targeting vulnerable NICU populations.

IMPLICATIONS FOR RESEARCH

While noise interventions show promise in the NICU, additional focused research is needed to further strengthen the evidence and inform clinical practice.

The effectiveness of earmuffs on the physiologic and behavioral stability in preterm infants

BACKGROUND

The use of earmuffs can protect preterm infants against negative effects of high noise levels in the neonatal intensive care unit. This study was aimed at assessing the effectiveness of the earmuffs on the physiologic and behavioral responses in preterm infants.

METHODS

A crossed over controlled trial was conducted at Aliasghar Hospital (Tehran, Iran) in 2014. Thirty-six preterm infants cared in closed incubators, 18 cases wore a pair of silicon earmuffs in the first day and the others were worn it at the second day. During 2 consecutive days, all subjects were observed as their own controls (without earmuffs). Physiologic (body temperature, heart rate, respiratory rate, systolic, diastolic pressures, arterial Oxygen Saturation) and behavioral responses (according to the Anderson behavioral state scoring system) were assessed every 2 h for 8 h long during daytime for two consecutive days.

RESULTS

The application of earmuffs could decrease the rate of the heart and respiratory while could increase the amount of oxygen saturation (p < 0.05). The results also showed that the preterm infants with earmuffs had lower ABSS score and a better light sleep compared to those without earmuffs (2.38 ± 0.47 versus 4.8 ± 0.97, p < 0.05).

CONCLUSION

The results indicated that using the earmuffs reduces the level of noise in NICUs following by improving the preterm neonates' physiological stability and behavioral states of ABSS.

Longitudinal Responses to Weighing and Bathing Procedures in Preterm Infants

Knowledge of the effects of nursing-induced stress on short-term outcomes in preterm infants is limited. Effects of 2 standard nursing procedures-weighing and bathing-on autonomic and motor stability of preterm infants were studied during their hospitalization. Outcomes were evaluated during and after the procedures. Eleven preterm infants were observed between 32 and 35 weeks' postmenstrual age (PMA) (postnatal days range: 4-63). Neonatal responses were assessed according to the Synactive Theory of Development and nursing was performed taking into account Newborn Individualized Developmental Care and Assessment Program (NIDCAP) principles. Effects of the studied nursing procedures on infants' stability during and after their execution were evaluated by nonparametric statistics. During monitored procedures, stress responses in autonomic and motor systems were observed at all PMAs. However, after 32 weeks' PMA, preterm infants also showed an autonomic and motor stability recovery 5 minutes after procedure completion. Contrary to our hypothesis, preterm infants showed to be stressed by weighing and bathing procedures up to 35 weeks' PMA. However, if facilitated and supported after nursing conclusion by interventions such as swaddling and nesting, according to NIDCAP principles, they recovered autonomic and motor stability by 5 minutes after ending procedures.

Cycled light in the intensive care unit for preterm and low birth weight infants

BACKGROUND

Potential benefits and harms of different lighting in neonatal units have not been quantified.

OBJECTIVES

• To determine effectiveness and safety of cycled light (CL) (approximately 12 hours of light on and 12 hours of light off) for growth in preterm infants at three and six months' corrected age (CA).• In separate analyses, to compare effects of CL with those of irregularly dimmed light (DL) or near darkness (ND), and effects of CL with those of continuous bright light (CBL), on growth in preterm infants at three and six months' CA.• To assess, in subgroup analyses, the effectiveness and safety of CL (vs control interventions (DL, ND and CBL)) introduced at different postmenstrual ages (PMAs) - before 32 weeks', at 32 weeks' and from 36 weeks' PMA - and to compare effectiveness and safety of CL for small for gestational age (GA) infants versus appropriately grown infants.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 12), MEDLINE via PubMed (1966 to January 2016), Embase (1980 to January 2016) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to January 2016). We searched clinical trials databases, conference proceedings and reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised or quasi-randomised trials of CL versus ND or CBL in preterm and low birth weight infants.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses according to the methods of the Cochrane Neonatal Review Group. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the quality of evidence.

MAIN RESULTS

We identified one additional study enrolling 38 participants for inclusion in this update, for a total of nine studies reporting on 544 infants. In general, the quality of the studies was low, mainly owing to lack of blinding and small sample sizes.Six studies enrolling 424 infants compared CL versus ND. No study reported on weight at three or six months. One study (n = 40) found no statistically significant difference in weight at four months between CL and ND groups. In another study (n = 62), the ratio of day-night activity before discharge favoured the CL group (mean difference (MD) 0.18, 95% confidence interval (CI) 0.17 to 0.19), indicating 18% more activity during the day than during the night in the CL group compared with the ND group. Two studies (n = 189) reported on retinopathy of prematurity (stage ≥ 3) and reported no statistically significant differences between CL and ND groups (typical risk ratio (RR) 0.53, 95% CI 0.25 to 1.11, I(2) = 0%; typical risk difference (RD) -0.09, 95% CI -0.19 to 0.01, I(2) = 0%). Two studies (n = 77) reported length of hospital stay (days) and noted a significant reduction in length of stay between CL and ND groups favouring the CL group (weighted mean difference (WMD) -13 days, 95% CI -23 to -2, I(2) = 0%; no heterogeneity). The quality of the evidence according to GRADE was low for this outcome. One study (n = 37) reported less crying at 11 weeks' corrected age (CA) in the CL group compared with the ND group (MD -0.57 hours/24 h, 95% CI -1.09 to -0.05). Tests for heterogeneity were not applicable.Three studies enrolling 120 infants compared CL versus CBL. Two studies (n = 79) reported significantly shorter length of stay in the CL group compared with the CBL group (WMD -16.5 days, 95% CI -26.2 to -6.8, I(2) = 0%; no heterogeneity). The quality of the evidence according to GRADE was low for this outcome. One study (n = 41) reported higher mean weight at three months' CA among infants cared for in the CL nursery (P value < 0.02) and a lower mean number of hours spent awake in 24 hours at three months of age (P value < 0.005). Data could not be entered into RevMan or GRADE. One study (n = 41) reported shorter time on the ventilator in the CL compared with the CBL group (MD -18.2 days, 95% CI -31.40 to -5.0). One study (n = 41) reported a shorter time to first oral feeding in the CL group (MD -6.8 days, 95% CI -13.29 to -0.31). We identified no safety issues.

AUTHORS' CONCLUSIONS

Trials assessing the effects of CL have enrolled 544 infants. No study reported on our primary outcome of weight at three or six months. Results from one additional study strengthen our findings that CL versus CBL shortens length of stay, as does CL versus ND. The quality of the evidence on both comparisons for this outcome according to GRADE was low. Future research should focus on comparing CL versus ND.

The onset of visual experience gates auditory cortex critical periods

Sensory systems influence one another during development and deprivation can lead to cross-modal plasticity. As auditory function begins before vision, we investigate the effect of manipulating visual experience during auditory cortex critical periods (CPs) by assessing the influence of early, normal and delayed eyelid opening on hearing loss-induced changes to membrane and inhibitory synaptic properties. Early eyelid opening closes the auditory cortex CPs precociously and dark rearing prevents this effect. In contrast, delayed eyelid opening extends the auditory cortex CPs by several additional days. The CP for recovery from hearing loss is also closed prematurely by early eyelid opening and extended by delayed eyelid opening. Furthermore, when coupled with transient hearing loss that animals normally fully recover from, very early visual experience leads to inhibitory deficits that persist into adulthood. Finally, we demonstrate a functional projection from the visual to auditory cortex that could mediate these effects.

Visual and auditory systems influence each other during development. Here, the authors show that the onset of eyelid opening regulates critical points during which the auditory cortex is sensitive to hearing loss or the restoration of hearing

Sound reduction management in the neonatal intensive care unit for preterm or very low birth weight infants

BACKGROUND

Infants in the neonatal intensive care unit (NICU) are subjected to stress, including sound of high intensity. The sound environment in the NICU is louder than most home or office environments and contains disturbing noises of short duration and at irregular intervals. There are competing auditory signals that frequently challenge preterm infants, staff and parents. The sound levels in NICUs often exceed the maximum acceptable level of 45 decibels (dB), recommended by the American Academy of Pediatrics. Hearing impairment is diagnosed in 2% to 10% of preterm infants versus 0.1% of the general paediatric population. Noise may cause apnoea, hypoxaemia, alternation in oxygen saturation, and increased oxygen consumption secondary to elevated heart and respiratory rates and may, therefore, decrease the amount of calories available for growth. Elevated levels of speech are needed to overcome the noisy environment in the NICU, thereby increasing the negative impacts on staff, newborns, and their families. High noise levels are associated with an increased rate of errors and accidents, leading to decreased performance among staff. The aim of interventions included in this review is to reduce sound levels to 45 dB or less. This can be achieved by lowering the sound levels in an entire unit, treating the infant in a section of a NICU, in a 'private' room, or in incubators in which the sound levels are controlled, or reducing the sound levels that reaches the individual infant by using earmuffs or earplugs. By lowering the sound levels that reach the neonate, the resulting stress on the cardiovascular, respiratory, neurological, and endocrine systems can be diminished, thereby promoting growth and reducing adverse neonatal outcomes.

OBJECTIVES

Primary objectiveTo determine the effects of sound reduction on growth and long-term neurodevelopmental outcomes of neonates. Secondary objectives1. To evaluate the effects of sound reduction on short-term medical outcomes (bronchopulmonary dysplasia, intraventricular haemorrhage, periventricular leukomalacia, retinopathy of prematurity).2. To evaluate the effects of sound reduction on sleep patterns at three months of age.3. To evaluate the effects of sound reduction on staff performance.4. To evaluate the effects of sound reduction in the neonatal intensive care unit (NICU) on parents' satisfaction with the care.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library), MEDLINE, EMBASE, CINAHL, abstracts from scientific meetings, clinical trials registries (clinicaltrials.gov; controlled-trials.com; and who.int/ictrp), Pediatric Academic Societies Annual meetings 2000 to 2014 (Abstracts2View(TM)), reference lists of identified trials, and reviews to November 2014.

SELECTION CRITERIA

Preterm infants (< 32 weeks' postmenstrual age (PMA) or < 1500 g birth weight) cared for in the resuscitation area, during transport, or once admitted to a NICU or a stepdown unit.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses according to the Cochrane Neonatal Review Group.

MAIN RESULTS

One small, high quality study assessing the effects of silicone earplugs versus no earplugs qualified for inclusion. The original inclusion criteria in our protocol stipulated an age of < 48 hours at the time of initiating sound reduction. We made a deviation from our protocol and included this study in which some infants would have been > 48 hours old. There was no significant difference in weight at 34 weeks postmenstrual age (PMA): mean difference (MD) 111 g (95% confidence interval (CI) -151 to 374 g) (n = 23). There was no significant difference in weight at 18 to 22 months corrected age between the groups: MD 0.31 kg, 95% CI -1.53 to 2.16 kg (n = 14). There was a significant difference in Mental Developmental Index (Bayley II) favouring the silicone earplugs group at 18 to 22 months corrected age: MD 14.00, 95% CI 3.13 to 24.87 (n = 12), but not for Psychomotor Development Index (Bayley II) at 18 to 22 months corrected age: MD -2.16, 95% CI -18.44 to 14.12 (n =12).

AUTHORS' CONCLUSIONS

To date, only 34 infants have been enrolled in a randomised controlled trial (RCT) testing the effectiveness of reducing sound levels that reach the infants' ears in the NICU. Based on the small sample size of this single trial, we cannot make any recommendations for clinical practice. Larger, well designed, conducted and reported trials are needed.

Heart rate variability evaluation in the assessment and management of in-utero drug-exposed infants

Aim:

To determine whether heart rate variability parameters vary between in-utero drug-exposed infants and controls. To determine correlations between Finnegan score and heart rate variability parameters. To differentiate those drug-exposed infants who require treatment from those infants who do not.

Methods:

A total of 24 jaundiced control subjects and 25 in-utero drug-exposed infants were enrolled. The Finnegan score and an electrocardiographic rhythm strip were obtained at 4-h intervals. RR intervals (time between consecutive R waves) were manually tabulated from the rhythm strip and analyzed. Time-domain heart rate variability parameters were calculated and analyzed for both groups.

Results:

Heart rate variability parameters were cumulatively lower over 3 days in in-utero drug-exposed infants compared with controls (p < 0.05). Root mean square of differences of standard deviation of RR intervals on first day of life, and standard deviation of RR intervals, percentage of consecutive RR intervals greater than 50 ms, and root mean square of differences of standard deviation of RR intervals on the second day of life were significantly lower between in-utero drug-exposed infants and control infants. Three out of five parameters were significantly lower in in-utero drug-exposed infants pre-treatment versus post-treatment (p = 0.001, p = 0.0001, and p = 0.021, respectively). Root mean square of differences of standard deviation of RR intervals was able to differentiate in-utero drug-exposed infants requiring opiate therapy and in-utero drug-exposed infants that did not (p = 0.02).

Conclusion:

Heart rate variability analysis can contribute to the management of in-utero drug-exposed infants. Heart rate variability could be used in dose titration.

Reducing noise levels in the NICU

In a neonatal intensive care unit (NICU), babies are subjected to various noises. Despite best intentions, staff and visitors alike contribute to a significant amount of "noise pollution" in the unit. One father came up with a solution that is now implemented nationwide and is making a huge difference to the nerves and the brain development of our most vulnerable population--NICU babies.