Computer model of oxygenation in neonates

Abstract

Maintaining a prescribed peripheral oxygen saturation (SpO2) target during routine care of neonates is challenging and inspired fraction of oxygen (FiO2) titration practices differ among caregivers and centers. Algorithms for automatic feedback control of SpO2 are being developed and tested, that would adapt to the changing neonatal organism and better maintain the required SpO2 target range. While clinical data is necessary to validate differences in the titration strategies, a continuous physiological model of oxygenation in neonates would facilitate baseline testing of different approaches, manual or automated. The objective of our study was to enhance a mathematical model of oxygenation of the neonate and to compare the performance of the model with available clinical data. We have implemented the diffusion resistance into the model as well as a variable oxyhemoglobin dissociation relationship and the bias between arterial and peripheral oxygen saturation. Values of model parameters were scaled to fit preterm infant scenarios. The comparison of the clinical data and computer simulations suggest that the model can reliably simulate episodes of oxygen desaturation and describe the relation between ventilation, FiO2and SpO2. It appears that the model may be an effective tool to test manual and automatic FiO2titration strategies.

Sensitivity analysis of a computer model of neonatal oxygen transport

“…We repeatedly run a 310s-long simulation that included a single desaturation episode due to apnoea. The desaturation episode was modelled based on the real clinical data of a premature male infant, 27 days old, weighing 1,019 grams that were used in our previous study [7] to preliminary validate the model.…”

“…In different models, Sands et al showed possibilities how to describe impaired gas transfer across the alveolar-capillary membrane by ventilation-perfusion mismatch [5] or elevated alveolarcapillary diffusion resistance [6]. In our project [7], Morozoff's model was enhanced in several ways; primarily a diffusion resistance (Rdiff) has been introduced into the model and the range of some physiological parameters of the model was estimated from neonatal literature rather than scaling from adults. The search for optimal values of internal parameters of the model with respect to available neonatal clinical data raised a question of the relative influence of the parameters on the model output signal, SpO2.…”

Statistical Description of SaO2–SpO2 Relationship for Model of Oxygenation in Premature Infants

“…In the last ten years, many articles have introduced closed-loop control algorithms of oxygenation in neonates, but a complex clinical study to compare the effectiveness of those various algorithms is still missing [6]. Clinical tests of the new oxygenation control algorithms of neonates bring safety and ethical risks, but a mathematical model of oxygenation in neonates can allow for the in silico simulation of oxygenation and preliminary comparison of the control algorithms [7][8][9][10].…”