Dr. Arnold's early contributions to science included studies to examine whether mathematic information in the pulse oximeter plethysmograph waveform can be used to measure pulsus paradoxus non-invasively and in real-time. If so, plethysmograph-estimate of pulsus paradoxus (PEP) will be a significant contribution to science and technology because it will provide clinicians an objective metric of acute exacerbation severity and response to treatment. He first studied healthy young adult participants who performed tidal-breathing through an airway circuit with adjustable inspiratory and expiratory resistance valves to generate pulsus paradoxus. PEP was calculated using a dedicated microprocessor and software program, based on change of plethysmograph waveform indices during the respiratory cycle. PEP predicted the degree of applied airway resistance. He has subsequently reported the validation of PEP using the criterion standards %-predicted FEV1 and airway resistance in the pulmonary function lab and in the emergency department with COPD and asthma. Assessment of acute asthma exacerbation severity directs treatment and the decision whether to hospitalize a patient, yet there are few objective measures to assess severity and predict outcome. His scientific contributions in this area have included work to improve assessment of acute exacerbations and to decrease variability of assessment between clinicians. These studies have examined the use of patient characteristics and clinical variables that are readily available at the bedside. He has demonstrated that select characteristics and variables can be used to accurately measure exacerbation severity and response to treatment with high inter-rater reliability. There are limited tools available to clinicians to inform hospitalization decisions for pediatric patients with acute asthma exacerbations. The scientific contributions of his team have included development and validation of the Asthma Prediction Rule (APR). This included development of both a comprehensive 15-variable and a reduced-form 5-variable prediction model for electronic decision-support. The APR might provide clinical decision-support to decrease unnecessary treatment variability, improve resource utilization, and improve patient outcomes measured using need-for-hospitalization criteria.

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Dr. Antoon is a NIH-funded clinical and health services researcher with a program focused on pharmacoepidemiology and medication safety in the pediatric population. As a physician-scientist, Dr. Antoon designs and conducts pragmatic clinical trials and population-based observational studies of medications, with a focus on the treatment of respiratory illness (e.g., pneumonia, influenza, COVID-19, RSV) in children. He evaluates the relationship between serious adverse events and medication exposures, as well as determining the role of drug-drug interactions and underlying infections in the development of serious adverse events in children. Dr. Antoon’s studies have investigated medication-related neurologic and psychiatric adverse events, severe cutaneous adverse reactions (e.g., Stevens Johnson Syndrome), cardiac events, and anaphylactic allergic reactions, among others.

Dr. Antoon is an expert on the safety and effectiveness of antivirals in the treatment of influenza and other respiratory viruses. He is the recipient of a NIH Career Development Award focused on determining the association between influenza, oseltamivir, and serious neuropsychiatric events, such as suicide or self-harm, encephalopathy, and psychosis.

Dr. Antoon has published more than 100 peer-reviewed articles and book chapters in the fields of pediatrics, pharmacology, and drug safety. He is a member of the Society for Pediatric Research, the International Society for Influenza and Other Respiratory Virus Diseases, and the International Society for Pharmacoepidemiology. Dr. Antoon was a 2021 recipient of the Young Investigator Award from the Academic Pediatric Association.

Dr. Antoon is a practicing pediatric hospitalist at Monroe Carell Jr. Children's Hospital at Vanderbilt. He is board certified in both General Pediatrics and Pediatric Hospital Medicine.

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Dr. Alrifai is an Assistant Professor of Pediatrics and Biomedical Informatics, a board-certified neonatologist in the Division of Neonatology at Vanderbilt University Medical Center (VUMC), and a board-certified clinical informatician in the Department of Biomedical Informatics. He holds a master's degree in applied clinical informatics. Dr. Alrifai is a VUMC HealthIT Clinical Director and the Medical Director for Inpatient Pediatric Informatics. He designed electronic health records clinical content for the VUMC neonatal intensive care unit (NICU) and multiple NICUs in Tennessee. Dr. Alrifai's research focus is clinical decision support (CDS) for pediatric care, workload and patient acuity modeling, and clinical analytics. He designed and published clinical trials to evaluate health information technology systems in neonatal care and has ongoing trials in the evaluation of CDS tools.

Dr. Acra is a Professor of Pediatrics and Chief of the D. Brent Polk Division of Pediatric Gastroenterology at Vanderbilt University Medical Center. He directs a busy clinical program with over 20,000 annual visits and more than 4,000 endoscopies. He has had a long academic career focused on clinical service, education and clinical research in the field of pediatric gastroenterology, hepatology and nutrition. His major clinical and research focus is in the area of upper gastrointestinal pathology, including dyspeptic, functional and diarrheal disorders and nutrition. With a background in chemical engineering, he has had a lifelong interest in intestinal transport phenomena and energy expenditure. Early in his career, he helped describe the function of several intestinal electrolyte and nutrient transporters in animal models and in humans.

His recent clinical nutrition research is focused on measuring energy expenditure in chronic disease states. Specifically, his research relates to measurement of energy metabolism in children using whole-room indirect calorimeters (metabolic chambers). This system is coupled with movement sensors to provide a similar-to-free-living environment where a study subject or patient's energy expenditure, substrate oxidation, physical activity and body composition are accurately measured on a minute-by-minute basis. Through this approach, his lab is investigating the physiological regulation of energy metabolism in children with inflammatory bowel disease and other chronic disease states, as well as improving the technologies for measuring body composition and physical activity.

With his background in engineering, he also has experience in developing and modeling new technologies. As Director of the Pediatric Aero-digestive Program, he is conducting studies on dyspeptic disorders, including piloting a novel non-invasive technology for measuring esophageal inflammation via measurement of mucosal electric resistance (plenary presentation at NASPGHAN, 2016) and co-developing a non-invasive tool to measure functional nausea based on gastric electromagnetic wave conduction abnormalities – now supported by recent R01 NIH funding.

As a pediatric gastroenterologist, Dr. Acra recognized that despite recent advances in our understanding of some congenital diarrheal disorders, undiagnosed Congenital Diarrheas and Enteropathies (CODE) still represent a considerable health problem for those affected, and sought to use his clinical and clinical research experience and the experience of his co-investigators at Vanderbilt University School of Medicine (Dr. Goldenring, leading epithelial biologist with expertise in transport and epithelial turnover; Dr. Correa, pediatric pathologist with extensive experience in intestinal pathology) to better understand these conditions. Supported by their preliminary work, they have hypothesized that identification of specific cellular abnormalities in children with CODEs, whole genome sequencing of effected neonates and their parents, and studying the disease by recapitulating it in defined biologic systems will lead to insights into the causes of CODE cases, and potentially lead to individualized treatments. This is demonstrated in the group’s work on understanding and reversing the transport-trafficking defect associated with the pathology of DGAT1 deficiency. This innovative approach, in collaboration with other major centers with common interests and complementary expertise, led to the creation of the PediCODE consortium, now funded by the NIH, with the goal of enhancing our ability to study the pathophysiology of CODE and improve diagnose, manage, and treat CODE.

Dr. Acra is also part of a multidisciplinary program continuously supported by the NIH for the past 25 years that investigates bio-psychosocial processes associated with pediatric functional abdominal pain. This group has phenotyped a cohort of over 800 pediatric patients with functional abdominal pain followed from childhood into adolescence and young adulthood. The results of these studies have led to published predictors of persistence of functional pain from childhood into adulthood, allowing earlier targeted care for those with greatest predilection for chronicity.

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