DRF Luftrettung releases findings on released droplets in rescue helicopters

Back in the autumn of 2019, DRF Luftrettung started a first scientific field test in co-operation with the German Consulting Centre for Hospital Epidemiology and Infection Control in Freiburg. The findings from this study enable initial conclusions about transmission pathways to be drawn, which the hygiene management team at DRF Luftrettung can use to build on.

The tests indicated that with a spontaneously breathing patient, there is a risk of pathogens not only spreading in the cabin, but also in the cockpit. The probability of infection depends on various factors like the type of pathogen, the transmission pathway and the exposure time. In the worst-case scenario – for example, a massive emission of droplets – there was a high probability of the pathogens not just settling on the surfaces in the entire cabin, but also spreading to the cockpit if there is no dividing curtain. In the presence of a curtain, the particles landed on it.

During the second test, with a short droplet emission – which is equivalent to a cough or brief separation from a breathing tube in real life – there were deposits around the patient but not in the cockpit. This implies that the duration of droplet release determines the range and the degree of contamination. Variables such as ventilation settings for heating or air conditioning, flight direction or flight maneuvers were also taken into consideration.

These findings enable various measures to be derived regarding patient and occupational protection: it is crucial to clean all surfaces in the cabin after transporting a highly infectious patient, because the restricted space increases the risk of contamination in comparison to a normal hospital room. Separating the cockpit and the cabin can generally also provide additional protection. Medical crews should wear personal protective equipment.