Comparative performances analysis of neonatal ventilators

Abstract

Background: Mechanical ventilation is a therapeutic action for newborns with respiratory diseases but may have side effects. Correct equipment knowledge and training may limit human errors. We aimed to test different neonatal mechanical ventilators' performances by an acquisition module (a commercial pressure sensor plus an isolated chamber and a dedicated software).

Methods: The differences (ΔP) between peak pressure values and end-expiration pressure were investigated for each ventilator. We focused on discrepancies among measured and imposed pressure data. A statistical analysis was performed.

Results: We investigated the measured/imposed ΔP relation. The ΔP do not reveal univocal trends related to ventilation setting parameters and the data distributions were non-Gaussian.

Conclusions: Measured ΔP represent a significant parameter in newborns' ventilation, due to the typical small volumes. The investigated ventilators showed different tendencies. Therefore, a deep specific knowledge of the intensive care devices is mandatory for caregivers to correctly exploit their operating principles.

Figure 1

Experimental set up. (a) Simplified scheme of set up applied to test ventilators. (b) Labview GUI for extrapolating parameters from the pressure wave delivered from ventilators: on the left the acquired pressure curve is shown in real time and the related air flow -Q- is reported below, according to the fictional C range imposed by the user; on the right, the pressure wave features that are extrapolated by the software are shown: T , fr , t_i and t_e , PIP, PEEP and ΔP , MAP, supposed V_T and VM.

Figure 2

ΔP experimental evaluation. (a) Trend of measured ΔP vs imposed ΔP values by using the BEAR CUB n.1 ventilator by varying ti values. (b) Histograms of mΔP-iΔP distributions for the 3 ventilators (n.3 BEAR, n.1 Leoni, n.1 Babylog), by using setting parameters used in clinical practice.