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

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.

Potential risk modifiers for severe intraventricular hemorrhage in very low birthweight infants requiring transport

BACKGROUND

Very low birthweight (VLBW) infants must undergo transport when born at a facility unequipped for their care. Previous research suggests an increased risk for intraventricular hemorrhage (IVH) associated with transport. It is unknown whether logistical aspects of transport, particularly mode and distance, or skill level of the resuscitation team are drivers of risk.

OBJECTIVE

To determine if the transport vehicle, distance traveled, or absence of advanced resuscitation team increased risk for severe IVH in outborn VLBW infants.

DESIGN/METHODS

Outborn VLBW infants, transported by specialized team via helicopter or ambulance to a Level IV NICU, were included; inborn VLBW infants served as controls. Infants transported >24 h after birth, by referring center's team, or without head ultrasound were excluded. Baseline clinical data were collected along with IVH grade, transport vehicle, distance traveled, and skill of resuscitation team.

RESULTS

Two hundred and ninety-three outborn were matched to 293 inborn infants. Outborn infants had increased incidence of severe IVH even when controlling for antenatal steroids, race, delivery method, and surfactant use (17% vs. 11%, OR = 1.6, 95% CI = 1.1-2.7). Despite this increased incidence, severe IVH was not associated with transport vehicle (p = .90; OR = 0.76, 95% CI = 0.34-1.7), distance traveled (p = .13; OR 0.84, 95% CI = 0.60-1.2), or skill of resuscitation team (p = .18; OR = 0.49, 95% CI = 0.21-1.1).

CONCLUSION

Compared to inborn, outborn infants had increased risk of severe IVH. Transport vehicle, distance traveled, and the skill of resuscitation team did not significantly impact risk.

Whole-body vibration in neonatal transport: a review of current knowledge and future research challenges

Interfacility transport to tertiary care for high-risk neonates has become an integral part of equitable access to optimal perinatal healthcare. Excellence in clinical care requires expertise in transport medicine and the coordination of safe transport processes. However, concerns remain regarding environmental stressors involved in the transportation of sick high-risk neonates, including noise and vibration. In order to mitigate the potential deleterious effects of these physical stressors during transport, further knowledge of the burden of exposure, injury mechanisms and engineering interventions/modifications as adjuncts during transport would be beneficial. We reviewed the current literature with a focus on the contribution of new and emerging technologies in the transport environment with particular reference to whole-body vibration. This review intends to highlight what is known about vibration as a physical stressor in neonates and areas for further research; with the goal to making recommendations for minimizing these stressors during transport.

Neurocritical care of high-risk infants during inter-hospital transport

The centralisation of neonatal intensive care in recent years has improved mortality, particularly of extremely preterm infants, but similar improvements in morbidity, such as neurodevelopmental impairment, have not been seen. Integral to the success of centralisation are specialised neonatal transport teams who provide intensive care prior to and during retrieval of high-risk neonates when in-utero transfer has not been possible. Neonatal retrieval aims to stabilise the clinical condition and then transfer the neonate during a high-risk period for patient. Transport introduces the hazards of noise and vibration; acceleration and deceleration forces; additional handling and temperature fluctuations. The transport team must stabilise the infant fully prior to transport as when on the move they are limited by space and movement to effectively attend to clinical deterioration. Inborn infants have better neurodevelopmental outcome compared with the outborn and aetiology of this seems to be multifactorial with the impact of transport itself during critical illness, remaining unclear. To improve the neurological outcomes for transported infants, it seems imperative to integrate the advancing intensive care neuromonitoring tools into the transport milieu. This review examines current inter-hospital transport neuromonitoring and how new modalities might be applied to the neurocritical care delivered by specialist transport teams.

Neuroprotection from acute brain injury in preterm infants

Infants born at ≤32⁺⁶ weeks gestation are at higher risk for intracranial ischemic and hemorrhagic injuries, which often occur in the first 72 hours postbirth. Antenatal strategies to reduce the incidence of acute brain injuries include administering maternal corticosteroids and prompt antibiotic treatment for chorioamnionitis. Perinatal strategies include delivery within a tertiary centre, delayed cord clamping, and preventing hypothermia. Postnatal strategies include empiric treatment with antibiotics when chorioamnionitis is suspected, the cautious use of inotropes, the avoidance of blood PCO2 fluctuation, and neutral head positioning. Clinicians should be aware of the policies and procedures that, especially when combined, can provide neuroprotection for preterm infants.

Neonatal transport services, a cross-sectional study

Objective: To understand the process and challenges facing neonatal transport in Canada and to delineate their composition and working.Subjects and methodology: An online questionnaire was sent to all neonatal transport team directors/coordinators in Canada. The questionnaire covered different aspects of transport and was pilot tested prior to finalization. The responses were anonymous to the investigators.Results: All sixteen neonatal transport teams in Canada surveyed. Fifteen teams responded. Dedicated team as a model was adopted by 12 teams (80%). A combined Neonatal/pediatrics team, where the team could be assembled by either neonatal or pediatrics intensive care staff, adopted by two (13%). Team members were cross-trained in about quarter of the teams (four teams out of 15) with respiratory therapists and registered nurses performing each other's roles. Neonatal Resuscitation Program was mandatory for all teams that responded (15 teams) to become certified as a neonatal transport team member. Nine teams use a central dispatch phone call system.Conclusion: As the first to comprehensively describe the status of neonatal transport in Canada, our study shows that neonatal transport teams have similarities as well as differences. Regionalization and differences in referral practices, geography, provincial laws, and manpower are the main reasons why teams may have their individual variations in policies, protocols, and logistics. Our data can be utilized by health professionals and policy makers to improve neonatal transport logistics within their health care systems resulting in better outcomes of transported neonates.