Device technique
The original IFU was developed prior to this study during the phase 1
clinical and simulation studies and included 22 operative steps. In this
IFU, the AVB was divided into six domains according to purpose (Table
2). It was hypothesised that the steps may vary between cases, depending
on factors such as station and position. Qualitative analysis provoked
and encouraged operators to discuss cases between themselves, either
through telephone calls or via a dedicated end-to-end encrypted messing
service.
Principal adaptions to the original IFU included (i) device application
during rather than between contractions, (ii) altering the application
angle and (iii) deflating the air cuff as soon as any aspect of the blue
deflation line became visible.