A pilot study to assess the safety, efficacy and ease of use of a novel hearing protection device for hospitalized neonates

Risk Factors for Hearing Screen Failure in a Single-Family Room Neonatal Intensive Care Unit

OBJECTIVE

 This study aimed to determine hearing screen outcomes and identify clinical and environmental risk factors for hearing screen failure in very preterm infants at a level IV single-family room (SFR) neonatal intensive care unit (NICU).

STUDY DESIGN

 We conducted a retrospective study of infants <33 weeks gestational age admitted to a level IV SFR NICU who survived to discharge and had automated auditory brainstem response results available. Demographics, antenatal and postnatal factors, and respiratory support modes and their duration were collected from the electronic medical record.

RESULTS

 Of 425 eligible infants with documented hearing screen results, 353 (83%) passed and 72 (17%) failed the hearing screen (unilateral, N = 44 [61%]; bilateral, N = 28 [39%]). Compared to infants who passed the hearing screen, infants with hearing screen failure were lower gestational age and birth weight, male sex, were screened at later postnatal and postmenstrual ages (PMAs), had lower 1- and 5-minute Apgar scores, longer duration of furosemide therapy, early hypotension, intraventricular hemorrhage (IVH) ≥Grade 3, and bronchopulmonary dysplasia (BPD) at 36 weeks PMA. Infants with hearing screen failure experienced longer exposures to invasive and noninvasive respiratory support. Heated, humidified, high flow nasal cannula >2 liters per minute exposure was significantly longer in infants with bilateral hearing screen failure (18.4 ± 18.4 d) compared to duration in infants who passed (7.4 ± 12.8 d) and those with unilateral failure (9 ± 13 d), (mean ± standard deviation [SD], p < 0.001). In the final logistic model, IVH ≥Grade 3 (odds ratio [OR] = 3.22, 95% confidence interval [CI]: 1.15-8.98, p = 0.026) and BPD (OR = 2.27, 95% CI: 1.25-4.11, p = 0.007) were the factors with the greatest risk for hearing screen failure.

CONCLUSION

 We speculate that the association of BPD with hearing screen failure may be mediated, in part, by chronic noise exposure, including from respiratory support devices. Attention to hearing protection in at-risk infants during respiratory support may mitigate the risk of hearing loss.

KEY POINTS

· NICU noise often exceeds recommended sound levels.. · Seventeen percent of infants with <33 weeks GA in SFR NICU failed hearing screenings.. · BPD and IVH are risk factors for hearing screen failure.. · Respiratory devices contribute to increased NICU noise.. · hearing protection should be considered during respiratory support..

Concerns about NICU Infants and Sleep

As a NICU parent, I was always wondering how my daughter could sleep through all of the noise in the NICU what with her very early birth. I was already concerned about her developmental outcomes due to the birth itself, but the alarms and noise in the NICU gave me incredible pause. So when I found about DREAMIES, a product that helps muffle the noise not only in the NICU but during transport and during an MRI, I was amazed.

Acoustic noise in a small-format 3.0-T neonatal MRI system

BACKGROUND

Today, magnetic resonance imaging (MRI) is rarely used in managing the care of premature neonates. This is in large part due to the medical and logistical challenges associated with moving neonates from the neonatal intensive care unit (NICU) to the radiology department. Furthermore, acoustic noise associated with MR scanning poses safety concerns for both practitioners and neonatal patients. A small-format 3.0-T neonatal scanner was recently developed and placed within the NICU to address these logistical and acoustic challenges.

OBJECTIVE

To compare acoustic noise measurements of a small-format 3.0-T neonatal MRI scanner with conventional adult-sized 1.5-T and 3.0-T MRI scanners using identical neonatal head imaging protocols.

MATERIALS AND METHODS

Sound pressure level (SPL) measurements of a standard imaging protocol were made in a small-format neonatal 3.0-T MRI scanner as well as in adult-sized 1.5-T and 3.0-T scanners. SPL measurements were made with a Brüel & Kjær sound level meter model 2250. The statistical significance of the differences in SPL between scanners was determined using one-way ANOVA.

RESULTS

Average sound pressure level values were measured in unweighted decibels (dB) and A-weighted decibels (dBA) for all imaging sequences in the protocol. The average A-weighted SPLs for the NICU from 1.5-T and 3.0-T MRI scanners were 81.02 ± 0.28 dBA, 87.00 ± 0.85 dBA, and 94.91 ± 0.65 dBA, respectively. SPLs at the isocenter of the NICU MRI scanner were 5.98 dBA quieter than in the 1.5-T scanner (P=0.007), and 13.89 dBA quieter than in the 3.0-T scanner (P<0.001). For staff standing next to the scanner, the NICU scanner was 20.24 dBA quieter than the 1.5-T scanner (P<0.001) and 19.28 dBA quieter than the 3.0-T scanner (P<0.001).

CONCLUSION

The NICU 3.0-T MRI system is significantly quieter than conventional adult-sized MRI systems, improving safety for neonatal patients. Significant reductions in SPL were also noted inside the screen room where clinicians may be present during scanning.

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.

Assessment of a hearing protection device on infant sleep in the neonatal intensive care unit

Premature infants often require prolonged hospitalisation in the neonatal intensive care unit (NICU) where they are exposed to adverse noise that may disrupt sleep and further compromise recovery and developmental outcomes. This single-session trial assessed the effects of a novel circumaural hearing protection device (DREAMIES®; NEATCAP Medical LLC) on sleep in 10 premature infants (mean 34.1 weeks GA) in a Level III NICU. Using polysomnography (PSG), the infant's sleep was compared between three interfeed periods throughout which DREAMIES® was ON or OFF. Each infant received the same condition order, OFF1-ON-OFF2. The PSG 30 s epochs were scored by a rater masked to the condition as Quiet Sleep, Active Sleep, Indeterminate Sleep, and Wake. There was a 14.1% increase in sleep from OFF1 to ON (p = 0.05) and an 18.4% decrease in sleep from ON to OFF2 (p = 0.02); an analogous inverse effect was observed for wake (χ2  = 5.03, p = 0.08). There was a main effect of DREAMIES on active sleep (χ2  = 7.4, p = 0.025) due to more active sleep for ON1 (46%) compared with OFF2 (32%; p = 0.074). No significant effect was observed for quiet sleep or indeterminate sleep. On average, the sound level was 51 dBA (range 36-113 dBA) and did not differ significantly among the three periods. The strongest relationship between the minute-by-minute maximum sound level and movement actigraphy was observed for the OFF1 condition (ρ0.301, p < 0.001). These findings suggest that DREAMIES® may augment sleep in premature infants by reducing acute episodes of adverse noise in the NICU.

Prevention of Noise-Induced Hearing Loss Using Investigational Medicines for the Inner Ear: Previous Trial Outcomes Should Inform Future Trial Design

Significance: Noise-induced hearing loss (NIHL) is an important public health issue resulting in decreased quality of life for affected individuals, and significant costs to employers and governmental agencies. Recent Advances: Advances in the mechanistic understanding of NIHL have prompted a growing number of proposed, in-progress, and completed clinical trials for possible protections against NIHL via antioxidants and other drug agents. Thirty-one clinical trials evaluating prevention of either temporary or permanent NIHL were identified and are reviewed. Critical Issues: This review revealed little consistency in the noise-exposed populations in which drugs are evaluated or the primary outcomes used to measure NIHL prevention. Changes in pure-tone thresholds were the most common primary outcomes; specific threshold metrics included both average hearing loss and incidence of significant hearing loss. Changes in otoacoustic emission (OAE) amplitude were relatively common secondary outcomes. Extended high-frequency (EHF) hearing and speech-in-noise perception are commonly adversely affected by noise exposure but are not consistently included in clinical trials assessing prevention of NIHL. Future Directions: Multiple criteria are available for monitoring NIHL, but the specific criterion to be used to define clinically significant otoprotection remains a topic of discussion. Audiogram-based primary outcome measures can be combined with secondary outcomes, including OAE amplitude, EHF hearing, speech-in-noise testing, tinnitus surveys, and patient-reported outcomes. Standardization of test protocols for the above primary and secondary outcomes, and associated reporting criterion for each, would facilitate clinical trial design and comparison of results across investigational drug agents. Antioxid. Redox Signal. 36, 1171-1202.

Physiologic dysregulation in newborns with prenatal opioid exposure: Cardiac, respiratory and movement activity

BACKGROUND

Newborns with prenatal opioid exposure (POE) are commonly diagnosed with neonatal abstinence/opioid-withdrawal syndromes due to characteristic symptoms and overt behaviors. However, little is known about the underlying physiology of opioid-exposed newborns.

OBJECTIVE

Cardiac, respiratory and movement activity were measured to identify physiologic dysregulation and quantify pathophysiologic instabilities of the central and autonomic nervous systems in POE newborns.

METHODS

In this pilot study, 30 hospitalized POE newborns (>35 wks gestational age) participated in one of two study phases wherein physiologic activity was measured for an 8-10 h session. In Phase 1, 17 infants received usual treatment to provide a general assessment of physiologic activity. In Phase 2, 13 infants participated in an interventional study (NCT02768844) using a prototype mattress that delivered stochastic vibratory stimulation (SVS). Changes in physiologic activity were compared for device on (N) and off (F) for three interfeed periods (FNF or NFN).

RESULTS

Phase 1 showed that although infants' heart rate was on average within normal newborn range (mean 137 bpm, SD 7), infants were tachycardic 16% of the study period and tachypneic (mean 74 breaths/min, SD 13) 62% of the period. Infants moved 33% of the period; 17% were durations >30 s. In Phase 2, heart rate, respiratory rate, movement duration and frequency were each reduced for SVS N compared to SVS F in the FNF protocol (P < 0.05).

CONCLUSION

Findings support that physiologic measures can identify dysregulation not captured with current withdrawal scoring assessments. Larger studies are warranted to assess if mattress SVS helps regulate pathophysiologic instabilities in infants with POE.