Sound levels in a neonatal intensive care unit significantly exceeded recommendations, especially inside incubators

Validity and use of the Neonatal Infant Stressor Scale: An integrative review

BACKGROUND

Stress exposure, operationalized as a count of painful or skin-breaking breaking procedures, is an important concept for inclusion in studies of preterm infants. The Neonatal Infant Stressor Scale (NISS) was developed to also account for nonpainful and environmental stressors; however, validity of this measure is unknown.

AIMS

The purpose of this review was to define the breadth of use of the NISS in neonatal research studies and determine its predictive and concurrent validity.

METHODS

Using the methods for integrative review, a systematic search of the literature was conducted using PubMed, CINAHL, PsycINFO, and Embase with keywords "NISS" OR "Neonatal Infant Stressor Scale". Study findings were narratively synthesized.

RESULTS

Twenty-nine articles were retained for the review and included two cross-sectional studies describing development or adaptation of the measure, two protocols for empirical studies, and 25 empirical studies of preterm infants. Modifications to the original NISS were common and included addition or exclusion of specific stressors and use of unweighted scores. Although findings were inconsistent across studies, limited data support the predictive validity of the NISS, as higher NISS scores have been associated with abnormal brain development and cognitive, motor, and behavioral deficits. Two studies found concurrent associations between NISS scores and cortisol.

CONCLUSION

The NISS may be a useful tool to quantify stressors experienced by preterm infants; however, there are only limited data to support its predictive or concurrent validity. The NISS may be particularly useful as a method to bring awareness to the infant's stress burden in clinical practice. Additional research is needed to validate inclusion of specific stressors in the NISS.

Quieting the neonatal intensive care unit: A quality improvement initiative

BACKGROUND

The neonatal intensive care unit (NICU) is vital for preterm infants but is often plagued by harmful noise levels. Excessive noise, ranging from medical equipment to conversations, poses significant health risks, including hearing impairment and neurodevelopmental issues. The American Academy of Pediatrics recommends strict sound limits to safeguard neonatal well-being. Strategies such as education, environmental modifications, and quiet hours have shown to reduce noise levels. However, up to 60% of the noises remain avoidable. High noise exposure exacerbates physiological disturbances, impacting vital functions and long-term neurological outcomes. Effective noise reduction in the NICU is crucial for promoting optimal neonatal development.

AIM

To measure the sound levels in a NICU and reduce ambient sound levels by at least 10% from baseline.

METHODS

A quasi-experimental quality improvement project was conducted over 4 mo in a 20-bed level 3 NICU in a tertiary care medical college. Baseline noise levels were recorded continuously using a sound level meter. The interventions included targeted education, environmental modifications, and organizational changes, and were implemented through three rapid Plan-Do-Study-Act (PDSA) cycles. Weekly feedback and monitoring were conducted, and statistical process control charts were used for analysis. The mean noise values were compared using the paired t-test.

RESULTS

The baseline mean ambient noise level in the NICU was 67.8 dB, which decreased to 50.5 dB after the first cycle, and further decreased to 47.4 dB and 51.2 dB after subsequent cycles. The reduction in noise levels was 21% during the day and 28% at night, with an overall decrease of 25% from baseline. The most significant reduction occurred after the first PDSA cycle (mean difference of -17.3 dB, P < 0.01). Peak noise levels decreased from 110 dB to 88.24 dB after the intervention.

CONCLUSION

A multifaceted intervention strategy reduced noise in the NICU by 25% over 4 months. The success of this initiative emphasizes the significance of comprehensive interventions for noise reduction.

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.

The effect of live music therapy on white matter microstructure in very preterm infants - A randomized controlled trial

OBJECTIVE

Music therapy (MT) is proposed to enrich the acoustic environment of very preterm infants (VPT) on the neonatal intensive care unit during a vulnerable period of brain development. The objective of this study was to investigate the effect of MT on the white matter (WM) microstructure. It is hypothesized that MT affects WM integrity in VPT.

METHODS

Randomized controlled trial enrolling infants born <32 weeks' gestation. Infants were randomized to MT or standard care. Live MT was provided twice weekly from the second postnatal week onwards by a trained music therapist. At term equivalent age, participants underwent a cranial magnetic resonance imaging scan including sequences for diffusion tensor imaging analysis. Differences in WM microstructure were assessed using tract based spatial statistics with fractional anisotropy.

RESULTS

Of 80 infants enrolled, 42 were eligible for diffusion tensor imaging analysis (MT: n = 22, standard care: n = 20). While primary tract based spatial statistics analysis revealed no significant differences between groups, post hoc analysis with uncorrected p-values and a significance threshold of p < 0.01 revealed significant fractional anisotropy differences in several WM tracts including the bilateral superior longitudinal fasciculus, the left forceps minor and left fasciculus uncinatus, the corpus callosum, the left external capsule, and the right corticospinal tract.

CONCLUSION

Post hoc analysis results suggest an effect of MT on WM integrity in VPT. Larger studies including long-term outcome are necessary to confirm these effects of MT on WM microstructure and to assess its impact on clinical neurodevelopment.

CLINICAL TRIAL REGISTRATION

Clinical trial number DRKS00025753.

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.

Impact of Quiet Time on Psychological Outcomes of Neonatal Intensive Care Unit Nurses in Jeddah, Saudi Arabia: A Cross-Sectional Study

BACKGROUND AND OBJECTIVE

Although quiet time is implemented in neonatal intensive care units (NICUs) for the benefit of infants, it may also positively impact the psychological outcomes of healthcare professionals. Several studies have examined the impact of quiet-time implementation on patients; however, there is a paucity of research assessing its impact on the psychological outcomes of NICU nurses, particularly in Saudi Arabia.

OBJECTIVE AND METHODS

This study aimed to assess the impact of quiet time on the psychological outcomes (stress, anxiety, and depression) of NICU nurses in Jeddah, Saudi Arabia. A cross-sectional design was used for this study. A total of 87 NICU nurses from two hospitals participated in this study. One group did not practice quiet time, while the second group did. A questionnaire survey assessed participants' demographic characteristics, and their depression, anxiety, and stress were assessed using the depression, anxiety, and stress scale-21 (DASS-21). The data were analyzed for frequency, percentage, mean, and standard deviation (SD). Bivariate analysis, independent t-tests, and one-way analysis of variance were used to test the differences between variables and groups. Pearson's correlation coefficient (r) was used to analyze the relationships between continuous variables and perceived stress, anxiety, and depression.

RESULTS

A substantial number of NICU nurses perceived stress, anxiety, and depression; however, there were no significant differences in perceived stress, anxiety, and depression between the nurses who worked in NICUs that applied quiet time and NICUs that did not (P ≤ 0.05).

CONCLUSION

This study found no statistically significant relationship between quiet-time implementation and perceived stress, anxiety, or depression among NICU nurses. Further research with a larger sample size or increased quiet-time implementation may be required.

Incubator-based active noise control device: comparison to ear covers and noise reduction zone quantification

BACKGROUND

Noise exposure in the neonatal intensive care unit (NICU) is consistently higher than current recommendations. This may adversely affect neonatal sleep, weight gain, and overall health. We sought to evaluate the effect of a novel active noise control (ANC) system.

METHODS

An ANC device's noise reduction performance was compared to that of adhesively affixed foam ear covers in response to alarm and voice sounds in a simulated NICU environment. The zone of noise reduction of the ANC device was quantified with the same set of alarm and voice sounds.

RESULTS

The ANC device provided greater noise reduction than the ear covers in seven of the eight sound sequences tested in which a noise reduction greater than the just noticeable difference was achieved. For noise in the 500 Hz octave band, the ANC device exhibited consistent noise reduction throughout expected patient positions. It provided better performance for noise below 1000 Hz than above 1000 Hz.

CONCLUSIONS

The ANC device provided generally superior noise reduction to the ear covers and provided a zone of noise reduction throughout the range where an infant would be placed within an incubator. Implications for patient sleep and weight gain are discussed.

IMPACT

Active noise control device can effectively reduce noise inside an infant incubator due to bedside device alarms. This is the first analysis of an incubator-based active noise control device and comparison to adhesively affixed silicone ear covers. A non-contact noise reduction device may be an appropriate means of reducing noise exposure of the hospitalized preterm infant.

The effect of using maternal voice, white noise, and holding combination interventions on the heel stick sampling

BACKGROUND

Heel stick sampling, a common procedure in newborns, causes acute pain.

AIMS

This study aims to measure the outcome of five various non-pharmacologic pain relief groups; maternal voice, white noise, holding, maternal voice+holding, and white noise+holding.

METHODS

The study is an open label, randomized controlled trial. A total of 178 newborns were included in this study. Newborns were randomly allocated to each group; white noise (n = 31), maternal voice (n = 31), holding (n = 30), white noise+holding (n = 29), maternal voice+holding (n = 28), and control (n = 29) interventions. Newborns' pain responses were evaluated using the Neonatal Infant Pain Scale (NIPS), and the Premature Infant Pain Profile (PIPP). The primary measured outcomes were the newborns' pain levels, while the secondary outcomes were the heart rate and changes in oxygen saturation. The mean values of pain in neonates between groups were evaluated one minute before (Phase1), during (Phase2), and one minute after (Phase3) the procedure.

RESULTS

The research results are given with comparisons in three time periods (Phase1, Phase2 and Phase3). White noise and white noise+holding were found to have the lowest mean NIPS and PIPP score (p < 0.001). The mean heart rate was found to be the lowest in the white noise+holding group (p < 0.001). There was no significant difference between the groups in terms of oxygen saturation score (p = 0.453).

CONCLUSION

The white noise+holding applied to newborns during heel stick sampling were effective in pain reduction. Nurses and midwives can use white noise+holding method.

IMPLICATIONS TO PRACTICE

These results contribute to the pain management of newborns.

Measurement of sound levels in a neonatal intensive care unit of a tertiary care hospital, Karachi, Pakistan

BACKGROUND

High sound levels in the neonatal intensive care unit (NICU) can alter preterm newborn hemodynamics and cause long-term neuro-developmental delays and hearing loss. The study aims to collate data on sound levels in a level IV NICU of a tertiary care hospital, identify the factors associated with them, and compare them with the international standards set by the World Health Organization (WHO), Environmental Protection Agency (EPA), and American Academy of Pediatrics (AAP).

METHODS

We carried out a cross-sectional study in NICU from 8th April 2019 to 30th June 2019. Sound levels were recorded for 480 h, using a portable sound meter, the Larson Davis 824. We captured sound levels on alternate days, during different shifts and shift changes and in open pods and single isolation rooms within the NICU. Additionally, we documented the total census, acuity of care, number of staff, number of procedures, and number of items of equipment used. The data was analyzed using t-test, ANOVA, and logistic regression.

RESULTS

The average sound level (Leq) and the maximum level (Lmax) recorded were 60.66 ± 2.99 dBA and 80.19 ± 2.63 dBA, respectively, which exceeds international recommendations. The sound level gradually decreased from morning to night hours. The major increase in sound was observed during nursing shift change. Similarly, a significant increase in sound was observed in open bays compared to isolation rooms. However, no difference in sound levels was recorded during weekdays and weekends. The number of healthcare professionals and the number of procedures performed were strongly associated with an increased noise level.

CONCLUSION

Sound levels in NICU were beyond the safety range and international recommendations. We observed a significant sound increment during morning hours and at the time of nursing shift change. High sound levels were associated with increased number of healthcare workers and bedside procedures in NICU.

Vibroacoustic Study in the Neonatal Ward

Neonatal wards are often subject to excessive noise pollution. Noise pollution encompasses two concepts, noise and vibration; their main difference being that a noise is heard and a vibration is felt in the body. The latter is what can be transmitted within the incubators of neonatal inpatients. This fact needs to be explored in depth. This work shows the results of the diagnosis of vibrations transmitted within the incubators that could affect neonates admitted to the neonatal unit of the Francesc de Borja University Hospital (Gandía, Spain). For this purpose, the vibrations reaching the neonate head resting area were recorded, taking into account different points, scenarios, days, and time slots. It could be observed that due to the incubator's motor position, the levels obtained in some scenarios measured in this study exceeded the regulation-specified levels. The conclusion is that the greatest influence on vibrations is the incubator's own motor, with other possible sources of vibrations, such as the room's air conditioning, having less influence. Further studies are needed to determine whether this vibration is harmful or beneficial to the neonate.

Assessment of Neonatal Intensive Care Unit Sound Exposure Using a Smartphone Application

OBJECTIVE

This study aimed to determine the impact of neonatal intensive care unit (NICU) design and environmental factors on neonatal sound exposures. We hypothesized that monitoring with a smartphone application would identify modifiable environmental factors in different NICU design formats.

STUDY DESIGN

Minimum, maximum, and peak decibel (dB) recordings were obtained using the Decibel X phone app, and the presence of noise sources was recorded in each patient space at three NICUs over a 6-month period (December 2017 to May 2018). Data were analyzed by Student's t-test and ANOVA with Bonferroni correction. Data were collected at the University of Maryland Medical Center single family room (SFR) level IV and St. Agnes Healthcare hybrid pod/single family room level III NICU, Baltimore, MD and at Prince George's Hospital Center open-pod design Level III NICU, Cheverly, MD.

RESULTS

All recordings in the three NICUs exceeded the American Academy of Pediatrics (AAP) recommended <45 dB level. The maximum and peak dB were highest in the open pod format level III NICU. Conversations/music alone and combined with other factors contributed to increased sound exposure. Sound exposure varied by day/night shift, with higher day exposures at the level III hybrid and open pod NICUs and higher night exposures at the level IV SFR NICU.

CONCLUSION

Although sound exposure varied by NICU design, all recordings exceeded the AAP recommendation due, in part, to potentially modifiable environmental factors. A smartphone application may be useful for auditing NICU sound exposure in quality improvements efforts to minimize environmental sound exposure.

KEY POINTS

· Smartphone application was used to assess NICU sound exposure.. · All cases of sound exposure exceed recommendations.. · A smartphone application was used to identify modifiable factors..

Acoustic conditioning of the neonatal incubator compartment: Improvement proposal

The objective of this work focuses on the study of the main sources of noise associated with incubators and the acoustic effects that derive from them. The method that has been established is based on tests carried out under different operating conditions of the incubators. Noise levels are analyzed under different boundary conditions (Neonatal ICU and "Controlled environment rooms"). Under normal operating conditions, the levels inside the incubator are around 56 dB (A), values that exceed the maximum limits recommended by the American Academy of Pediatrics. The scope of this study is to evaluate the existing noise levels in the incubator and analyze possible design improvements. The study was carried out in the hospitals of Cádiz, Huelva, and Malaga.

Newborn Incubators Do Not Protect from High Noise Levels in the Neonatal Intensive Care Unit and Are Relevant Noise Sources by Themselves

BACKGROUND

While meaningful sound exposure has been shown to be important for newborn development, an excess of noise can delay the proper development of the auditory cortex.

AIM

The aim of this study was to assess the acoustic environment of a preterm baby in an incubator on a newborn intensive care unit (NICU).

METHODS

An empty but running incubator (Giraffe Omnibed, GE Healthcare) was used to evaluate the incubator frequency response with 60 measurements. In addition, a full day and night period outside and inside the incubator at the NICU of the University Hospital Zurich was acoustically analyzed.

RESULTS

The fan construction inside the incubator generates noise in the frequency range of 1.3-1.5 kHz with a weighted sound pressure level (SPL) of 40.5 dB(A). The construction of the incubator narrows the transmitted frequency spectrum of sound entering the incubator to lower frequencies, but it does not attenuate transient noises such as alarms or opening and closing of cabinet doors substantially. Alarms, as generated by the monitors, the incubator, and additional devices, still pass to the newborn.

CONCLUSIONS

The incubator does protect only insufficiently from noise coming from the NICUThe transmitted frequency spectrum is changed, limiting the impact of NICU noise on the neonate, but also limiting the neonate's perception of voices. The incubator, in particular its fan, as well as alarms from patient monitors are major sources of noise. Further optimizations with regard to the sound exposure in the NICU, as well as studies on the role of the incubator as a source and modulator, are needed to meet the preterm infants' multi-sensory needs.

Effect of environmental music on autonomic function in infants in intensive and growing care units

BACKGROUND

The aim of this study is (1) to observe the effect of the background music (BGM) in the incubator on heart rate variability (HRV) during the first few weeks of life in preterm infants in the neonatal intensive (NICU) and growing care units (GCU) and (2) to investigate the effect of environmental music on autonomic function in the infants.

METHODS

Thirty infants, including premature (26 3/7 - 38 4/7 weeks) and low-birth weight (LBW) (946-2,440 g) infants, admitted to the NICU or GCU were involved. The heart rate, low- (LF, 0.05-0.15 Hz) and high- (HF, 0.15-0.4 Hz) frequency HRV components, and LF/HF ratio were measured. The BGM, lullabies for a baby, was delivered through a speaker in the incubator, and the HRV components were compared among before, during, and after intervention with BGM.

RESULTS

The mean HR did not change among the experimental conditions. The LF and HF values decreased during the BGM condition, but not LF/HF, compared with the condition before BGM.

CONCLUSIONS

The present results showed that an auditory environment affected the autonomic function of infants with a range of BGM in the NICU/GCU. The present study also suggested that BGM, a non-invasive and non-pharmacological intervention, could be an evaluation tool for autonomic function in infants in NICU/GCU.

Influence of Quiet Time on the Auditory Environment of Infants in the NICU

OBJECTIVE

To determine the influence of quiet time on the auditory environment of infants in the NICU and to compare the effect of quiet time by room type, bed type, and infant clinical acuity.

DESIGN

Cross-sectional, descriptive comparison study.

PARTICIPANTS

Sixty-six infants born at less than 38 weeks gestation who were between 32 and 40 weeks postmenstrual age.

SETTING

The auditory environments of infants in two level 3 NICUs within a pediatric hospital system in the Southeastern United States. Each NICU implemented quiet time for 4 hours per day.

METHODS

We assessed the auditory environment of the participants using Language Environmental Analysis technology. We used paired t tests to assess differences in the auditory environment during quiet versus nonquiet time and to compare the effect of quiet time by room type, bed type, and clinical acuity.

RESULTS

During quiet time, the auditory environment of participants had 13% more silence, 17% fewer electronic sounds, 25% less speech, and 30% fewer words than during nonquiet time. We observed greater differences in quiet time versus nonquiet time for infants in open bays and incubators and infants who had greater acuity.

CONCLUSION

Our results support the implementation of quiet time to increase silence and reduce exposure to electronic sounds for infants in the NICU. Additional research is necessary to further examine the effect of quiet time on the auditory environment of infants in the NICU with consideration of environmental and clinical variables.

Assessing speech exposure in the NICU: Implications for speech enrichment for preterm infants

OBJECTIVE

Quantify NICU speech exposure over multiple days in relation to NICU care practices.

METHODS

Continuous measures of speech exposure were obtained for preterm infants (n = 21; 12 M) born <34 weeks gestational age in incubators (n = 12) or open cribs (n = 9) for 5-14 days. Periods of care (routine, developmental) and delivery source (family, medical staff, cuddler) were determined through chart review.

RESULTS

Infants spent 13% of their time in Care, with >75% of care time reflecting developmental care. Speech counts were higher during care than no care, for mature vs. immature infants, and for infants in open cribs vs. incubators. Family participation in care ranged widely, with the highest speech counts occurring during periods of intentional voice exposure.

CONCLUSIONS

Care activities represent a small portion of NICU experiences. Speech exposure during Developmental Care, especially with intentional voice exposure, may be an important source of stimulation. Implications for care practices are discussed.

Incubator-based Sound Attenuation: Active Noise Control In A Simulated Clinical Environment

Objective

Noise in the neonatal intensive care unit can be detrimental to the health of the hospitalized infant. Means of reducing that noise include staff training, warning lights, and ear coverings, all of which have had limited success. Single family rooms, while an improvement, also expose the hospitalized infant to the same device alarms and mechanical noises found in open bay units.

Methods

We evaluated a non-contact incubator-based active noise control device (Neoasis™, Invictus Medical, San Antonio, Texas) in a simulated neonatal intensive care unit (NICU) setting to determine whether it could effectively reduce the noise exposure of infants within an incubator. In the NICU simulation center, we generated a series of clinically appropriate sound sequences with bedside medical devices such as a patient monitor and fluid infusion devices, hospital air handling systems, and device mechanical sounds. A microphone-equipped infant mannequin was oriented within an incubator. Measurements were made with the microphones with the Neoasis™ deactivated and activated.

Results

The active noise control device decreased sound pressure levels for certain alarm sounds by as much as 14.4 dB (a 5.2-fold reduction in sound pressure) at the alarm tone’s primary frequency. Frequencies below the 2 kHz octave band were more effectively attenuated than frequencies at or above the 2 kHz octave band. Background noise levels below 40 dBA were essentially not impacted by the active noise control device.

Conclusions

The active noise control device further reduces noise inside infant incubators. Device safety and potential health benefits of the quieter environment should be verified in a clinical setting.

The effects of auditory interventions on pain and comfort in premature newborns in the neonatal intensive care unit; a randomised controlled trial

OBJECTIVE

This study investigated the effects of three auditory interventions; white noise, recorded mother's voice, and MiniMuffs, applied during a heel lance on pain and comfort in premature infants in the neonatal intensive care units.

DESIGN AND METHODS

This experimental, parallel, randomised controlled research was conducted in a state hospital tertiary-level neonatal intensive care unit. The sample comprised sixty-four premature infants with gestational ages of 31-36 weeks. The infants were randomly assigned to four groups: i) white noise, ii) recorded mother's voice, iii) MiniMuffs, and iv) control. Pain and comfort of newborns were evaluated according to the Neonatal Infant Pain Scale (NIPS) and the COMFORTneo scale. Oxygen saturation, heart rate, and crying time were also measured.

RESULTS

The mean of oxygen saturation levels in the white noise, recorded mother's voice, and MiniMuffs group were higher than the control group. The heart rate, crying time, mean NIPS score, COMFORTneo score of the premature neonates in the white noise, recorded mother's voice, and MiniMuffs groups were significantly lower than the control group (p < .001).

CONCLUSION

Auditory interventions used during heel lance reduce the pain and increase the comfort of the premature infants. White noise is extremely effective in preventing infants's pain.

A two-pronged approach to reduce noise levels in the neonatal intensive care unit

OBJECTIVES

The aim of this study was to assess the efficacy of a visual noise feedback system and "quiet time" in reducing noise levels in the neonatal intensive care unit (NICU).

DESIGN

A prospective cross-sectional study was performed in a combined level II/III NICU at a Canadian tertiary care hospital. Noise levels were recorded continuously for three weeks without and then three weeks with visual noise feedback system. Noise levels were compared after one year of using visual feedback, and subsequently with the addition of two "quiet times."

RESULTS

Visual feedback reduced noise levels from 54.2 dB (95% CI 53.8-54.7 dB) to 49.4 dB (95% CI 48.9-49.8 dB; P < 0.0001) and increased the amount of time spent under 45 dB from 0 to 25% (P < 0.0001) after three weeks of use. However, this effect was not sustained at one year of visual feedback, with noise levels at 54.7 dB (95% CI 54.5-55.0 dB, P = 0.55). Quiet Time did not further reduce daily noise in the NICU (average noise levels 54.7, 95% CI 54.4-55.0 dB, P = 0.836).

CONCLUSIONS

While visual noise feedback system reduced noise levels in the short term, these effects were not sustainable at one year and could not be remediated with the addition of a Quiet Time initiative. Continuing education regarding the detrimental effects of noise is paramount to ensure persistent noise reduction in the NICU.

Differences in early auditory exposure across neonatal environments

BACKGROUND

To date, no study has compared preterm and full term auditory environments.

AIM

To define differences in auditory exposure for preterm infants at term equivalent age in the neonatal intensive care unit (NICU) compared to auditory exposure in hospital rooms on a labor and delivery ward after full term birth.

STUDY DESIGN

Ninety-eight infants (48 preterm infants born 28 weeks gestation in the NICU at term equivalent age and 50 full term infants in a hospital room on the labor and delivery ward within 4 days of birth) had auditory exposure measured over a single 16-hour period using the Language Environment Acquisition (LENA) device.

RESULTS

More language (p < 0.001) was observed on the labor and delivery ward than in the NICU, with an average of 3.3 h more language in a 16-hour period and an average of 14,110 more words spoken around infants in a 16-hour period on the labor and delivery ward (p < 0.001). More electronic sounds were observed in the NICU, with an average of 2.3 h more in the 16-hour period (p < 0.001). The average decibel level in the NICU was lower than in the hospital rooms on the labor and delivery ward (57.16 ± 2.30 dB, compared to 63.31 ± 2.22 dB; p < 0.001).

CONCLUSION

The NICU auditory environment for preterm infants is different than the auditory environment for full term infants, with less language, more electronic sounds, and quieter stimuli. This understanding can aid in developing appropriate interventions that enhance positive forms of auditory exposures.

Environmental noise levels in hospital settings: A rapid review of measurement techniques and implementation in hospital settings

BACKGROUND

Hospitals provide treatment to improve patient health and well-being but the characteristics of the care environment receive little attention. Excessive noise at night has a negative impact on in-patient health through disturbed sleep. To address this hospital staff must measure night-time environmental noise levels. Therefore, an understanding of environmental noise measurement techniques is required. In this review, we aim to 1) provide a technical overview of factors to consider when measuring environmental noise in hospital settings; 2) conduct a rapid review on the equipment and approaches used to objectively measured noise in hospitals and identify methodological limitations.

DESIGN

: A rapid review of original research articles, from three databases, published since 2008. Studies were included if noise levels were objectively measured in a hospital setting where patients were receiving treatment.

RESULTS

1429 articles were identified with 76 included in the review. There was significant variability in the approaches used to measure environmental noise in hospitals. Only 14.5% of studies contained sufficient information to support replication of the measurement process. Most studies measured noise levels using a sound level meter positioned closed to a patient's bed area in an intensive care unit.

CONCLUSION

: Unwanted environmental noise in hospital setting impacts negatively on patient and staff health and well-being. However, this literature review found that the approaches used to objectively measure noise level in hospital settings have been inconsistent and poorly reported. Recommendations on best-practice methods to measure noise levels in hospital environments are provided.

Preterm infant showed better object handling skills in a neonatal intensive care unit during silence than with a recorded female voice

AIM

This study compared whether preterm infants showed better tactile abilities during silence or when they heard a prerecorded female voice at different intensities.

METHODS

We studied 74 preterm infants of 28-35 weeks' postconceptional age who were admitted to a French neonatal intensive care unit from 2014 to 2017. They were presented with wooden objects, one smooth and one angled, at various points during silence (n = 26) or while listening to a female voice at +5 (n = 24) or +15 decibels (n = 24) inside their incubator. We compared the conditions to see if there was any difference in how the infants handled the objects and also compared familiar and unfamiliar objects.

RESULTS

The preterm infants showed better handling skills and only displayed effective discrimination, during silence. We found that 27.1% of the infants exposed to female voices failed to get habituated to the object, compared to 7.7% in the silence condition (p < 0.05) and success during the voice conditions required more trials (6.1 vs. 5.3) than the silence condition (p = 0.05). The different voice intensities made no difference.

CONCLUSION

Being exposed to a female voice had a negative impact on preterm infants' tactile sensory learning, regardless of its intensity.

[Prematurity, progress and challenges]

Prematurity is one of the main causes of neonatal mortality and comorbidities, and longer term sequalae. The survival rate and quality of life of premature babies has however progressed significantly and infants benefit from improved monitoring and long-term follow-up. Notable advances have been made in the area of developmental care, although their implementation in units needs to be improved. Innovations in perinatology should emerge in the years ahead.

Sound as a supportive design intervention for improving health care experience in the clinical ecosystem: A qualitative study

PURPOSE

Most prior hospital noise research usually deals with sound in its noise facet and is based merely on sound level abatement, rather than as an informative or orientational element. This paper stimulates scientific research into the effect of sound interventions on physical and mental health care in the clinical environment.

METHODS

Data sources comprised relevant World Health Organization guidelines and the results of a literature search of ISI Web of Science, ProQuest Central, MEDLINE, PubMed, Scopus, JSTOR and Google Scholar.

RESULTS

Noise induces stress and impedes the recovery process. Pleasant natural sound intervention which includes singing birds, gentle wind and ocean waves, revealed benefits that contribute to perceived restoration of attention and stress recovery in patients and staff.

CONCLUSIONS

Clinicians should consider pleasant natural sounds perception as a low-risk non-pharmacological and unobtrusive intervention that should be implemented in their routine care for speedier recovery of patients undergoing medical procedures.