Monitoring the respiratory rate by miniature motion sensors in premature infants: a comparative study.

OBJECTIVE

Existing respiratory rate (RR) monitors suffer from inaccuracy. The study assesses the accuracy of a novel modality that monitors lung ventilation with miniature motion sensors.

STUDY

DESIGN

RR was measured by three methods: impedance technology, motion sensors and visual count, in babies (n=9) that breathed spontaneously or with respiratory support and babies (n=12) that received high-frequency oscillatory ventilation (HFOV).

RESULTS

A line close to equality (slope=0.96, r(2)=0.83) was obtained between the motion sensor and the visual count of the RR with narrow 95% limits of agreements (<14.0 b.p.m.). The relationship between the impedance and the visual count showed a lower correlation (r(2)=0.65) and wider 95% limits of agreements (21.4 b.p.m.). The motion sensor- and the ventilator-determined RRs demonstrated a good agreement during HFOV, whereas the impedance failed to measure the RR during HFOV.

CONCLUSION

Monitoring RR with motion sensors is more accurate compared with the impedance, in infants, in all ventilation modes.