A white-box model for real-time simulation of acid-base balance in blood plasma.

Maintaining an optimal acid base is important for the patient. The theory underlying acid-base balance can be challenging for clinicians and educators. These considerations justify creating simulations that include realistic changes to the partial pressure of carbon dioxide, pH, and bicarbonate ion concentration in a range of conditions. Our explanatory simulation application requires a model that derives these variables from total carbon dioxide content and runs in real time. The presented model is derived from the Stewart model, which is based on physical and chemical principles, and takes into account the effects of weak acids and strong ions on the acid-base balance. An inventive code procedure allows for efficient computation. The simulation results match target data for a broad range of clinically and educationally relevant disturbances of the acid-base balance. The model code meets the real-time goals of the application and can be applied in other educational simulations. Python model source code is made available.

Electronic Decision Support in the Delivery Room Using Augmented Reality to Improve Newborn Life Support Guideline Adherence: A Randomized Controlled Pilot Study.

INTRODUCTION: The Newborn Life Support (NLS) guideline aims to provide healthcare professionals a consistent approach during neonatal resuscitation. Adherence to this and analogous guidelines has repetitively been proven to be difficult.This study evaluates adherence to guideline using a novel augmented reality (Microsoft HoloLens) electronic decision support tool during standardized simulated neonatal resuscitation compared with subjects working from memory alone. METHODS: In this randomized controlled pilot study, 18 professionals responsible for neonatal resuscitation were randomized to the intervention group and 11 to the control group. Demographic characteristics were similar between both groups. A standardized neonatal resuscitation scenario was performed, which was recorded and later assessed for adherence to the NLS algorithm by 2 independent reviewers. Secondary outcomes were error classification in case of algorithm deviation and time to the execution or completion of critical steps in the algorithm to determine delay. RESULTS: Median (interquartile range) scores of a theoretical maximum of 40 in the intervention group were 34 (32.5-35.5) versus 29 (27-33) in the control group ( P = 0.004). Errors of commission were committed less frequently with the electronic decision support tool 2 (1-2.5) compared with 4 (2-4) in the control group ( P = 0.029). Analysis of time to initiation or completion of key steps in the NLS algorithm showed no significant differences between both groups. CONCLUSIONS: Healthcare professionals using an electronic decision support tool showed improved adherence to the NLS guideline during simulated neonatal resuscitation.

Jan Beneken (1934-2021): European modeling and simulation pioneer.

This obituary highlights a number of contributions by Professor Jan Beneken (1934-2021) to modeling of human physiology and pharmacology and to simulation-based training.

Explanatory models in neonatal intensive care: a tutorial.

BACKGROUND: Acute care providers intervening on fragile patients face many knowledge and information related challenges. Explanation based on causal chains of events has limitations when applied to complex physiological systems, and model-driven educational software may overwhelm the learner with information. We introduce a new concept and educational technology to facilitate understanding, reasoning, and communication in the clinical environment. The aim is to grasp complex physiology in a more intuitive way. EXPLANATORY MODELS EM: An EM is a representation of relevant physiologic processes that provides insight into the relationships between therapeutic interventions and monitored variables, and their dependency on incidents and pathologies. We systematically analyze types of information incorporated into models and displayed in simulations and consider their explanatory relevance. TRANSPOSITION OF THE GREAT ARTERIES TGA: A conceptual model (diagram) of the normal neonatal cardiorespiratory system is adapted to reflect TGA and implemented in animated, interactive software. ILLUSTRATION OF EDUCATIONAL USE: The use of this model is illustrated via the explanation to pediatric residents of the relationships between blood pressures, blood flow rates, ventilation, oxygen saturation, and oxygen distribution in a neonate with TGA. Learners explore clinical scenarios and effects of therapeutic interventions. DISCUSSION: Explanatory models hold promise as mental models for clinical practice and could possibly play a role in clinical decision making in neonatal intensive care and beyond. COMPANION SOFTWARE: The software is freely available via the web addendum: https://www.dropbox.com/sh/ciufq5rqxgs9bkt/AAC7oKsvkEr73eYUJkx0pZ1Ya?dl=0.

Is octreotide treatment useful in patients with congenital chylothorax?

BACKGROUND: Congenital chylothorax (CC) is a severe congenital disorder characterized by the collection of chyle in the pleural space. Recent case reports suggest that the use of octreotide in the treatment of CC may be useful. OBJECTIVE: To evaluate the effect of octreotide on pleural effusions in CC. METHODS: Hospital records of 7 patients with a CC, who were admitted to the Neonatal Intensive Care Unit of the Radboud University Nijmegen Medical Centre between 2006 and 2010 and were treated with octreotide, were retrospectively evaluated. RESULTS: There was no clear and consistent effect of octreotide treatment on pleural effusions. Pleural effusions eventually decreased in all patients after reaching a dose of 5-6 µg/kg/min, but this could also reflect the natural history of CC. Out of 7 patients, 4 were diagnosed with persistent pulmonary hypertension of the newborn. No other known side effects of octreotide were found. There was a mortality rate of 30%. CONCLUSIONS: No clear and consistent effect of octreotide was identified. Pulmonary hypertension was a common problem in this patient group. It is not clear whether or not this was caused or maintained by octreotide treatment. A randomized controlled trial is needed to investigate the safety and usefulness of octreotide. Until then, clinicians should be careful in using octreotide, especially when persistent pulmonary hypertension is present.