Excessive exposure of sick neonates to sound during transport

[Does the nursing shortage in neonatal intensive care units (NICU) threaten the warranty of healthcare for newborns? : The "Mary and Joseph" project]

BACKGROUND

Germany has been experiencing a dramatic shortage of nursing staff for years that particularly affects neonatal intensive care units (NICUs). It is assumed that this situation leads to reductions in bed capacities, resulting in negative effects on the healthcare of newborns. These were investigated through a retrospective observational study using the example of three NICUs at the University Hospital of Munich (LMU).

METHODS

For the four-year observation period from August 2017 to May 2021, time series data from the "Quality Assurance Guideline for Premature and Mature Infants" (QFR-RL) of the Federal Joint Committee, bed resource analysis, planned personnel statistics, clinical logout data, and rescue service data were mutually examined using descriptive statistics and regression analysis.

RESULTS

During the observation period, around 21% of the necessary nursing staff positions were vacant, although the quality of nursing care for newborns seemed to have been guaranteed. However, to ensure quality, given the staff shortage, several available beds had to be blocked. In this context, both an increase in the number of hours the wards were logged off from population care and an increase in the relative risk of neonatal intensive care transfer were observed, resulting in a transfer every three days on average.

DISCUSSION

A shortage of nursing staff reduces the neonatal hospital bed capacity, since neonatal nursing care quality is regulated by strict legally binding guidelines, the QFR-RL. This is why the consequences for the security of care for the population through hospital cancellations and a risk of transfer must be accepted on a regular basis.

Smartphone monitoring of in-ambulance vibration and noise

Transferring sick premature infants between hospitals increases the risk of severe brain injury, potentially linked to the excessive exposure to noise, vibration and driving-related accelerations. One method of reducing these levels may be to travel along smoother and quieter roads at an optimal speed, however this requires mass data on the effect of roads on the environment within ambulances. An app for the Android operating system has been developed for the purpose of recording vibration, noise levels, location and speed data during ambulance journeys. Smartphone accelerometers were calibrated using sinusoidal excitation and the microphones using calibrated pink noise. Four smartphones were provided to the local neonatal transport team and mounted on their neonatal transport systems to collect data. Repeatability of app recordings was assessed by comparing 37 journeys, made during the study period, along an 8.5 km single carriageway. The smartphones were found to have an accelerometer accurate to 5% up to 55 Hz and microphone accurate to 0.8 dB up to 80 dB. Use of the app was readily adopted by the neonatal transport team, recording more than 97,000 km of journeys in 1 year. To enable comparison between journeys, the 8.5 km route was split into 10 m segments. Interquartile ranges for vehicle speed, vertical acceleration and maximum noise level were consistent across all segments (within 0.99 m . s^-1, 0.13 m · s^-2 and 1.4 dB, respectively). Vertical accelerations registered were representative of the road surface. Noise levels correlated with vehicle speed. Android smartphones are a viable method of accurate mass data collection for this application. We now propose to utilise this approach to reduce potential harmful exposure, from vibration and noise, by routing ambulances along the most comfortable roads.

Finding Comfortable Routes for Ambulance Transfers of Newborn Infants

Early inter-hospital ambulance transport of premature babies is associated with more severe brain injury. The mechanism is unclear, but they are exposed to excessive noise and vibration. Smart-routing may help minimise these exposure levels and potentially improve outcomes.An app for Android smartphones was developed to collect vibration, noise and location data during ambulance journeys. Four smartphones, with the app installed, were provided to the local neonatal transport group to attach to their incubator trolleys. An example of route comparison was performed on the roads used between Nottingham City Hospital (NCH) and Leicester Royal Infirmary (LRI).Almost 1,700 journeys were recorded over the space of a year. 39 of these journeys travelled from NCH to LRI, comprising of 9 different routes. Analysis was performed on all recorded data which travelled along each road. For routes from NCH to LRI, the route with least vibration was also the quickest. Noise levels, however, were found to increase with vehicle speed. Ambulance drivers in the study did not tend to take the quickest, smoothest or quietest route.Android smartphones are a practical method of gathering information about the in-ambulance environment. Routes were found to vary in vibration, noise and speed, suggesting these could be minimised. The next step is to combine recorded and clinical data to try and define an ideal neonatal comfort metric which can then be fed into the routing. Roll-out of the app around the UK is also planned.Clinical relevance-Transferring preterm neonatal infants to specialist units lead to worse outcomes. By reducing the levels of vibration and noise the infants are exposed to during transport, we hope to improve outcomes.

NeoSTRESS: Study of Transfer and Retrieval Environmental StressorS upon neonates via a smartphone application - Sound

AIM

This study aimed to measure sound exposure during neonatal retrieval, determine whether this varied with mode of transport, and compare noise exposure to recommended levels in neonatal intensive care units. We also aimed to assess the acceptability of using a smartphone application to measure sound.

SETTING

Neonatal retrieval service in Brisbane, Australia.

METHODS

The Physics Toolbox Sensor Suite application was installed on a Samsung Galaxy S5 smartphone and calibrated for sound measurement. Data were collected during outbound, non-patient legs of 45 retrievals - 25 road, 11 fixed wing aircraft and 9 rotary aircraft journeys. Data were saved to cloud storage, then analysed using PostgreSQL database.

RESULTS

The median sound level was 83 dB (interquartile range 66-91; range 27-≥97 dB). Continuous equivalent sound (L_eq ) was 90 dB across all journeys. Rotary transport was loudest (L_eq 94 dB). Fixed wing (L_eq 89 dB) and road (L_eq 87 dB) journeys also resulted in significant sound exposure. Sound exceeded recommended levels (45 dB) for 99% of all journey time, regardless of the mode of transport.

CONCLUSIONS

Neonates encounter harmful sound levels during retrieval - louder than recommended levels for 99% of all retrieval time. Sounds levels were highest in rotary aircraft transport compared to fixed wing or road transport. It is feasible to use a calibrated smartphone application instead of a sound metre.

Do transport factors increase the risk of severe brain injury in outborn infants <33 weeks gestational age?

OBJECTIVE

We evaluated transport factors and postnatal practices to identify modifiable risk factors for SBI.

STUDY DESIGN

Retrospective review of Canadian Neonatal Transport Network data linked to Canadian Neonatal Network data for outborns <33 weeks gestational age (GA), during January 2014 to December 2015. SBI was defined as grade 3 or 4 intraventricular hemorrhage or parenchymal echogenicity, including hemorrhagic and/or ischemic lesions.

RESULT

Among 781 infants, 115 (14.7%) had SBI with range 5.6-40% among transport teams. In multivariable analysis, SBI was associated with GA [0.77 (0.71, 0.85)] per week, receipt of chest compressions and/or epinephrine at delivery [1.81 (1.08, 3.05)] and receipt of fluid boluses [1.61 (1.00, 2.58)].

CONCLUSIONS

Risk factors for SBI were related to the condition at birth and immediate postnatal management and not related to transport factors. These results highlight the importance of maternal transfer to perinatal centers to allow optimization of perinatal management.

Decreasing sound and vibration during ground transport of infants with very low birth weight

OBJECTIVE

To measure the effectiveness of modifications to reduce sound and vibration during interhospital ground transport of a simulated infant with very low birth weight (VLBW) and a gestational age of 30 weeks, a period of high susceptibility to germinal matrix and intraventricular hemorrhage.

STUDY DESIGN

Researchers measured vibration and sound levels during infant transport, and compared levels after modifications to the transport incubator mattresses, addition of vibration isolators under incubator wheels, addition of mass to the incubator mattress and addition of incubator acoustic cover.

RESULT

Modifications did not decrease sound levels inside the transport incubator during transport. The combination of a gel mattress over an air chambered mattress was effective in decreasing vibration levels for the 1368 g simulated infant.

CONCLUSION

Transport mattress effectiveness in decreasing vibration is influenced by infant weight. Modifications that decrease vibration for infants weighing 2000 g are not effective for infants with VLBW. Sound levels are not affected by incubator covers, suggesting that sound is transmitted into the incubator as a low-frequency vibration through the incubator's contact with the ambulance. Medical transportation can apply industrial methods of vibration and sound control to protect infants with VLBW from excessive physical strain of transport during vulnerable periods of development.

[Laser treatment for retinopathy of prematurity in neonatal intensive care units. Premature Eye Rescue Program]

INTRODUCTION

Retinopathy of prematurity is a leading cause of childhood blindness around the world.

AIM

The Department of Ophthalmology at the Semmelweis University and the Peter Cerny Neonatal Emergency and Ambulance Service started an innovative Premature Eye Rescue Program to reduce the non-essential transport of premature babies suffering from retinopathy of prematurity.

METHOD

During the first 5 years 186 eyes of 93 premature babies were treated at the bedside with stage 3 retinopathy of prematurity in the primary hospitals.

RESULTS

In this first 5-years period the authors reduced the number of transports of premature babies for laser treatment; 93 children avoided the unnecessary transport, saving altogether a distance of 21,930 kilometers for children, as well as the ambulance service.

CONCLUSIONS

The Premature Eye Rescue Program offers a good and effective alternative for treatment of retinopathy in the primary hospitals. The authors propose the national extension of this program.

How comfortable is neonatal transport?

AIMS

Discomfort and stress have been widely studied in the newborn baby but data are lacking for the infant undergoing transport. The aim of our study was to identify infant discomfort during road transport and its pattern.

METHODS

This was a prospective cohort study on all infants transported by the Yorkshire Neonatal Transport Service over a 6-month period. The same environmental measures were used for each baby. The premature infant pain profile was used to measure stress and discomfort at five specified times during transport. The score before any intervention was the gold standard.

RESULTS

Of 239 transport episodes, 140 had complete data. Twenty-four babies were ventilated and routinely sedated with morphine, and the remaining babies had no pain relief. The same pattern of premature infant pain profile (PIPP) score was seen in all infants regardless of gestation or sedation. The raw PIPP scores (and data when ranked) peaked during road transport, and this was a significant change compared to baseline observations. This pattern was consistent across all gestational age groups. The sedated/ventilated babies showed the same pattern although it was blunted.

CONCLUSION

All babies showed higher levels of discomfort during transport compared to baseline. More work is needed to develop interventions that could potentially decrease this.

Neonatal intensive care practices harmful to the developing brain

There has been a marked increase in the survival of extremely low birth weight (ELBW) infants, but these babies have a long stay in the NICU. Strategies to decrease their neurodevelopmental impairment become very important. The maximum development of the brain occurs between 29-41 weeks. From the warm, dark, acquatic econiche, where the baby hears pleasant sounds like the mother's heart beat, the baby suddenly finds itself in the dry, cold, excessively bright, noisy, environment of the NICU. Noise, bright light, painful procedures, and ill-timed caregiving activities, adversely affect the infant's development. Excessive radiation from X-rays of babies on the ventilator and CT scans also affect the brain. Medications like steroids for chronic lung disease also cause damage to the brain. Aminoglycides and frusemide are known to cause hearing impairment. Hence a developmentally supportive, humanized care will go a long way in enhancing the developmental outcome of these babies.

Physical stressors during neonatal transport: helicopter compared with ground ambulance

OBJECTIVES

This study was undertaken to assess concurrent mechanical stresses from shock, vibration, and noise to which a critically ill neonate is exposed during emergency transfer.

METHODS

For neonates transported by a French specialized emergency medical service, we measured and analyzed 27 physical parameters recorded during typical transport by ambulance and by helicopter. The noninvasive sensors were placed to allow better representation of the exposure of the newborn to the physical constraints.

RESULTS

Based on 10 hours of transport by ambulance and 2 hours by helicopter, noise, whole body vibration, rate of turn, acceleration, and pitch were extracted as the five most representative dynamic harshness indicators. A helicopter produces a higher-level but more stable (lower relative dispersion) whole body dynamic exposure than an ambulance, with a mean noise level of 86 ± 1 dBA versus 67 ± 3 dBA, mean whole body vibration of 1 ± 0.1 meter per second squared (m/s(2)) versus 0.4 6 0.2 m/s(2), and acceleration of 1 6 0.05 m/s(2) versus 0.4 6 0.1 m/s(2). A ground ambulance has many more dynamic effects in terms of braking, shock, and impulsive noise than a helicopter (1 impulsive event per 2 minutes vs. 1 per 11 minutes).

CONCLUSIONS

Our results show significant exposure of the sick neonate to both stationary and impulsive dynamic physical stressors during transportation, particularly in a ground ambulance. The study suggests opportunities to reduce physical stressors during neonatal transport.

Noise levels in a neonatal transport incubator in medically configured aircraft

OBJECTIVE

The purpose of this study was to evaluate exposure of neonates to noise during air medical transport as few commercially available hearing protective devices exist for premature newborns during air medical transport.

METHODS

Sound pressure levels in an infant incubator during actual flight conditions in four common medically configured aircraft were measured. Three noise dosimeters measured time-weighted average noise exposure during flight in each aircraft. One dosimeter was placed in the infant incubator, and the remaining dosimeters recorded noise levels in various parts of the aircraft cabin.

RESULTS

The incubator provided a 6-dBA decrease in noise exposure from that in the crew cabin. The average noise level in the incubator in all aircraft was close to 80 dB, much higher than the proposed limits of 45 dB for neonatal intensive care unit noise exposure or 60 dB during transport.

CONCLUSIONS

Exposure of neonates to elevated noise levels during transport may be harmful, and steps should be taken to protect the hearing of this patient population.

Protection against noise-induced hearing loss in young CBA/J mice by low-dose kanamycin

Animal studies indicate that a combination of kanamycin (KM) and noise produces a synergistic effect, whereby the threshold shift from the combination is greater than the sum of the shifts caused by either agent alone. Most such studies have focused on adult animals, and it has remained unclear whether younger, presumably more susceptible, animals show an even greater synergistic effect. The present study tested the hypothesis that young CBA/J mice receiving a low dose of KM (300 mg/kg, 2x/day, s.c.) from 20 to 30 days post-gestational age followed by brief noise exposure (110 dB SPL; 4-45 kHz, 30 s) would show greater noise-induced permanent threshold shifts (NIPTS) than mice receiving either treatment alone. Noise exposure produced 30-40 dB of NIPTS and moderate hair cell loss in young saline-treated mice. KM alone at this dose had no effect on thresholds. Surprisingly, mice receiving KM plus noise were protected from NIPTS, showing ABR thresholds not significantly different from unexposed controls. Mice receiving KM prior to noise exposure also showed significantly less outer hair cell loss than saline-treated mice. Additional experiments indicated protection by KM when the noise was applied either 24 or 48 h after the last KM injection. Our results demonstrate a powerful protective effect of sub-chronic low-dose kanamycin against NIPTS in young CBA/J mice. Repeated kanamycin exposure may establish a preconditioned protective state, the molecular bases of which remain to be determined.

Setting up a neonatal transport service: air transport

Air transport is an integral part of any system that provides neonatal care in the developed world. To ensure that this is developed in an efficient and appropriate manner a prospective analysis is required to allow a multidisciplinary team to progress a project aimed at providing appropriate staff with adequate training using equipment that has satisfied all regulatory bodies. This article highlights the difficulties in achieving this, reflecting on the way in which established air transport teams have overcome many of the difficulties. The commonalities with land based transport are emphasised along with those issues which are specific to teams providing such a service who aspire to become "air capable".

The acoustic hood: a patient-independent device improving acoustic noise protection during neonatal magnetic resonance imaging

BACKGROUND

Magnetic resonance imaging (MRI) is today the imaging modality of choice to investigate the neonatal brain. However, the acoustic noise during scanning is very loud, often exceeding 100 dBA.

AIM

To reduce the acoustic noise during MRI for neonatal patients. If effective, this would create a safer environment and also result in fewer aborted examinations due to poor image quality from patient motion.

METHODS

A passive acoustic noise protector, the acoustic hood, was built out of dampening material. Sound pressure measurements with and without the acoustic hood were performed using our clinical neonatal scan protocol, consisting of eight imaging sequences. The acoustic hood is placed over the newborn inside the MR scanner tunnel during the examination to absorb acoustic noise.

RESULTS

The acoustic noise level was substantially reduced using the acoustic hood. Peak sound pressure was reduced 16.18-22.21 dBA depending on the pulse sequence. For the entire frequency spectra, reduction were between 4-13.59 dBA again varying with the pulse sequence.

CONCLUSION

Acoustic noise can be reduced further than before by using the patient-independent acoustic hood in addition to other noise protection. We recommend the use of three passive hearing protections during neonatal MRI: (1) dental putty, (2) paediatric ear muffs, and (3) the acoustic hood.

Fit to fly: practical challenges in neonatal transfers by air

Air transport of infants in incubators should be undertaken in a manner that is safe for both staff and infant and satisfies all directives by appropriate regulatory bodies. In Scotland during the last two years, certification of an infant incubator system for use in both rotary and fixed wing aircraft has been accomplished. This is a report of the issues addressed during this project, which will be common to all neonatal transport services intending to develop air transport capability.