Using a novel smartphone app to track noise and vibration exposure during neonatal ambulance transport

Objective: To assess the utility of a bespoke smartphone app to map noise and vibration exposure across neonatal road ambulance journeys.

Design and setting: Prospective observational study of ambulance journeys across a large UK neonatal transport service. Smartphones, with an in-house developed app, were secured to incubator trolleys to collect vibration and noise data for comparison with international standards. A case study exploring alternative routes between hospitals was undertaken.

Results: Over a 12-month period, the app was used to collect data from 1487 interhospital journeys totalling 81 925 km. Noise positively correlated with increasing vehicle speed. Noise exposure never fell below the recommended 45 dB(A) threshold for neonatal patients and exceeded 70 dB(A) for more than 60% of the time. During patient transfers, vibration would be classed as uncomfortable for healthy adults for 68% of journeys. Comparison of 111 journeys on two different routes between the same hospitals demonstrated significantly lower vibration exposure depending on the road type. Safe levels of adult vibration exposure were exceeded on 19% of non-motorway and 3% of motorway journeys between the two hospitals. Vibration and noise levels were significantly higher on concrete compared with asphalt road surface.

Conclusions: It is feasible for neonatal teams to collect detailed route, vibration and noise exposure data using a calibrated smartphone and bespoke app. Collecting large amounts of data and providing live measures to teams could help quantify excessive exposures and guide reduction strategies of these environmental stressors for the benefit of babies, staff and equipment.