Abstract
Determining nocturnal respiratory rate by acoustic means in children
Respiratory rate is an important vital sign not only in sleep medicine, but also in the diagnosis of several respiratory and non-respiratory diseases. Depending on the children’s age, respiratory rates above 40 bpm can be a reason for hospitalization.
By using the LEOSound Lung Sound Monitor, which can already detect wheezing and coughing, we developed an algorithm to determine the respiratory rate by acoustic means. The aim of this study was to validate the developed algorithm.
We compared the respiratory rate calculated by the algorithm with the respiratory rate counted manually by a medical expert (rater). We used 30 night-time recordings of children between the ages of 4 and 15 (Ø 8.7 ± 3.3 years) with a height of 135.5 (± 24.7) cm and a weight of 40.0 (± 26.4) kg.
Table 1 shows the mean respiratory rate of algorithm and rater, grouped by the children’s age. We added the mean deviation between rater and algorithm for these groups.
|
Age 4 – 5 Years (n = 10) |
Age 6 – 11 Years (n = 11) |
Age 12 – 15 Years (n = 9) |
| Rater |
18.6 +/- 2.0 bpm |
17.7 +/- 2.9 bpm |
16.3 +/- 1.8 bpm |
| Algorithm |
19.3 +/- 1.5 bpm |
18.5 +/- 2.6 bpm |
17.4 +/- 1.7 bpm |
| Mean deviation |
1.4 +/- 0.4 bpm |
1.2 +/- 0.4 bpm |
1.6 +/- 0.9 bpm |
Table 1: Mean respiratory rate from algorithm, rater and mean deviation between rater and algorithm
The results show a mean deviation between rater and algorithm of less than 2 bpm. Using the developed algorithm, the LEOSound Monitor is able to monitor the nocturnal respiratory rate in children, thus provides new opportunities in the monitoring of diseases such as Asthma or Pneumonia. Further studies are planned to validate this algorithm for adults.