Abstract â–¡ 61

We recorded with polyvinylidenefluoride(PVDF) polymer detector respiration signals of premature babies without direct contact to the skin of subject. The piezoelectric PVDF-detector can be put, e.g., under the matress of the baby, and the minimal body movements caused by respiration will produce the electrical potential difference between the upper and lower surface of the polymer detector. These potentials will be amplified and forward filtered with bandpass of 0.1 to 1.5 cps by means of APNEREC-recorder unit. This device has been also programmed to produce an alarm sound, if the apnoe periodes exceed the certain time. The sensitivity of the alarm level in relation to the amplitude of signal can be also changed, e.g., the alarm parameters can be adjusted as follows: if the respiration signal is a period of 10 sec. below 10% of total output potential, the device alarms. It also includes one external output for respiration signal making it possible to record respiration signals in hard-disk of the computer.

We have tested the usefullness of our method in 10 premature babies suffering from breathing disorders. Their gestation age varied from 28 weeks to 38 weeks. The recordings were performed in three of 10 subjects in the incubator, in seven of them in the cradle. Recording time varied from 5 hours to 4 days per subject.

This preliminary recording seems to show that our method is useful when non-invasive follow-up of respiration is indicated in newborn babies suffering from breathing disorders.