1.4 Study method
We designed a two-steps, pilot study to compare home-based virtual care vs. in-person physical evaluation. Two different units: a “bed-side” and a “remote” evaluation team were recruited.
The study was divided in three phases:
1. Identification of the auscultatory landmarks in SMA patients and concordance with the standard landmarks
Children were first assessed during one of the routine consultations by a pediatric neurologist with expertise in SMA, one pediatrician expert in digital health and one pediatric ultrasonographer who were in charge of locating optimal lung auscultation landmarks for each child with different methodologies. Each of them examined the children separately and located what she/he believed to be optimal chest auscultation landmarks after evaluating with either traditional stethoscope or lung ultrasound point of care (Fig. 2). According to her/his expertise, each of the examiners filled the medical reports for each patient, drawing an individual map of auscultation landmarks and specifying any additional respiratory (vesicular murmur, crackle, rhonchus, wheeze, pleural rub or stridor) or sonographic findings.
The landmarks identified by the multidisciplinary team were compared to the standard auscultation landmarks, four on the back and four on the front, provided by the device for patients with typical configuration of chest and trunk in the absence of spinal deformities.
Fig. 2 Identification of optimal chest auscultation landmarks
2. Training sessions and application of the new device by carers
The medical part of the “remote” team gave a 30 minutes in-person practical training. The carers were shown how to place the device following the map of optimal landmarks identified for each child and to perform lung auscultation while an ICT expert offered technical support for the whole team. After training, as soon as they felt confident, they autonomously placed the Tytocare digital stethoscope at the corresponding landmarks, perform the entire respiratory evaluation back and front on their own, made sure each lung recording was as clear as possible without background noise (the device provide such features) and forward the files. In case of poor quality recording sessions the device displays on its screen several alert messages inviting the examiner to repeat the step until acceptable quality is obtained before moving forward. At the end of the session parents alone or with their children, recorded one or more free short videos to describe their experiences, ease-of -use, difficulties, expectations and so on.
3. Assessment of accuracy and sensitivity of the device in our cohort of SMA children.
Data obtained by the carers were reviewed by an independent pediatric team who blindly accessed the encrypted patient’s charts. The blinded team examined the lung sounds from each recorded station (landmarks) using high quality headset in a quiet room and filled a report assigning an overall quality value, from 1 (very poor) to 5 (very good), identify and report possible interfering/background noise (mechanical ventilation, heart sounds, voices, rustle, TV/music) for each of the auscultation landmark
The blinded team also compared the recordings of respiratory findings obtained using the device by the carers with the reports of the bedside team who used conventional auscultation techniques.