Fully automated predictive intelligent control of oxygenation (PRICO) in resuscitation and ventilation of preterm lambs

Abstract

Articles Translational Investigation nature publishing groupBackground: Hyperoxia and hypoxia influence morbidity and mortality of preterm infants. Automated closed-loop control of the fraction of inspired oxygen (FiO 2 ) has been shown to facilitate oxygen supplementation in the neonatal intensive care unit (NICU), but has not yet been tested during preterm resuscitation. We hypothesized that fully automated FiO 2 control based on predefined oxygen saturation (SpO 2 ) targets was applicable in both preterm resuscitation and ventilation. Methods: Twenty-two preterm lambs were operatively delivered and intubated in a modified EXIT procedure. They were randomized to receive standardized resuscitation with either automated or manual FiO 2 control, targeting SpO 2 according to the Dawson curve in the first 10 min and SpO 2 90-95% hereafter. Automated FiO 2 control also was applied during surfactant replacement therapy and subsequent ventilation. results: Time within target range did not differ significantly between manual and automated FiO 2 control during resuscitation, however automated FiO 2 control significantly avoided hyperoxia. Automated FiO 2 control was feasible during surfactant replacement and kept SpO 2 within target range significantly better than manual control during subsequent ventilation. conclusion: In our model, fully automated FiO 2 control was feasible in rapidly changing physiologic conditions during postnatal resuscitation and prevented hyperoxia. We conclude that closed loop FiO 2 control is a promising tool for the delivery room.o xygen supplementation is one of the most common therapeutic interventions in resuscitation and neonatal intensive care of term and preterm infants (1). However, both hypoxia and hyperoxia must be avoided because of their detrimental effects on morbidity and mortality in these children. While hypoxia may lead to direct and indirect cellular damage, hyperoxia has been associated with oxygen toxicity, oxidative stress (2), and chronic diseases of preterm infants such as bronchopulmonary dysplasia (3) and retinopathy of prematurity (4).Increase in oxygenation after birth is a gradual process (5). Measurement of oxygen saturation (SpO 2 ) by pulse oximetry in the delivery room is feasible in newborn resuscitation (6) and in preterm infants within the first minutes of life (7). SpO 2 reference values of preterm infants increase within the first 10 min of life (5). This has led to SpO 2 target values incorporated in the current European Resuscitation Council guidelines on resuscitation of newborns (8). In order to avoid hyperoxia, current recommendations advise resuscitation of preterm infants with a mixture of air and oxygen, and to use fraction of inspired oxygen (FiO 2 ) between 0.21 and 0.30 (9). FiO 2 should subsequently be titrated according to SpO 2 (10,11). General use of pulse oximetry has been shown to extensively reduce O 2 -derived toxicity in preterm infants (12). However, keeping SpO 2 manually within changing saturation limits during a hectic period of resu...

Automated control of inspired oxygen (FiO2) in preterm infants: Literature review

“…Another largely diffused rule‐based non‐fuzzy control system is the Predictive Intelligent Control of Oxygenation (PRICO) which is integrated in an infant ventilator (Fabian HFO ® , Acutronic, Hirzel, Switzerland) to maintain patients’ SpO 2 (Radical Masimo ® ). This system has been validated in the animal model, but there are not published studies in infants. The algorithm is a control scheme that uses the current SpO 2 together with the SpO 2 trend .…”

“…This system has been validated in the animal model, but there are not published studies in infants. The algorithm is a control scheme that uses the current SpO 2 together with the SpO 2 trend . The trend is used to adjusts the FiO 2 step size by recognizing larger and quicker changes and to limit insufficient or excessive corrections .…”

“…The algorithm is a control scheme that uses the current SpO 2 together with the SpO 2 trend . The trend is used to adjusts the FiO 2 step size by recognizing larger and quicker changes and to limit insufficient or excessive corrections . Moreover, before the adjustment of FiO 2 , the system checks for parameters of proper ventilation (ie: TV and percentage of leak), reliable connections between all devices, and correctness of all measured parameters …”

Development and preclinical testing of an adaptive algorithm for automated control of inspired oxygen in the preterm infant

“…The design of the algorithm is fundamental to the function of the device. Contemporary algorithms each have an element of rule-based control,8 9 13 20 whereby FiO 2 adjustments to SpO 2 fluctuations are made based on a decision table developed by clinical experts. This approach offers the reassurance of clinical input to the decision-making, but the rules for FiO 2 alteration are arbitrary and in some cases limited in scope,9 13 20 meaning that the algorithm may not serve the needs of all individuals.…”

“…An ideal control algorithm would be capable of a timely response to these SpO 2 alterations without inducing instability. Algorithms with a lockout period after each FiO 2 adjustment9 20 may thus fail to respond to a critical SpO 2 deviation. The algorithm must also be capable of dealing with a protracted SpO 2 deviation (usually hypoxaemia) that has been refractory to the initial FiO 2 alterations called for by the algorithm, and also with ‘steady-state’ error that arises when the characteristics of the system under control alter gradually (eg, basal oxygen requirement changes).…”