[Assessment of respiratory physiology signals in very low-weight newborn infant with respiratory deficiency].

1. Lung function tests in newborn babies breathing spontaneously were performed commonly using a pneumotachometer to measure the tidal volume and an esophageal catheter to measure the transpulmonary pressure changes. 2. The quality of the measured signals depends on the breath-to-breath variability of the signals as well as on the frequency of different artifacts and disturbances due to physiological interferences. 3. The evaluation of the signals in very low birth weight infants with respiratory distress is often difficult due to the irregular pattern of respiration, the reduced signal-noise-ratio and the high number of artifacts. 4. The subjective assessment of the quality of 115 records of respiratory signals has shown that 54% of all records can be evaluated easily, in 40.8% the evaluation was difficult and in 5.2% an evaluation was not possible. 5. The qualitative analysis of respiratory signals shows that in this age group the computer-aided signal evaluation requires a new view in the detection and elimination of artifacts as well as in the calculation of characteristic results from a sufficient number of evaluated breathing cycles.