Randall Wetzel, Director
Randall Wetzel, MBBS, MRCP, LRCS, MSB, FAAP, FCCM, is the founder and Director of The Laura P. and Leland K. Whittier VPICU at Children’s Hospital Los Angeles. He is a tenured Professor of Pediatrics and Anesthesiology at the University of Southern California and has served as an attending physician in pediatric critical care for over 40 years both at Johns Hopkins Hospital and at Children’s Hospital Los Angeles. He has served as the Director of Critical Care Medicine and as the Chairman of Anesthesiology Critical Care Medicine at CHLA. He has trained hundreds of residents and over 100 critical care fellows. He also founded Virtual Pediatric Systems which collects information of all admissions to over 200 pediatric ICUs in the United States.
Melissa Aczon, Principal Data Scientist & Manager
Melissa Aczon, Ph.D. manages the VPICU team and projects. She has a Bachelor of Science in Mathematics from Harvey Mudd College and a Ph.D. in Scientific Computing and Computational Mathematics from Stanford University. She enjoys leveraging her math background to formulate and solve detection and estimation problems from a wide array of applications. Prior to joining CHLA, Dr. Aczon was a Principal Scientist at Arete Associates where she led a team of scientists and engineers to develop algorithms for a very complex sensor system.
Sareen Shah, Clinician Data Scientist
Sareen Shah, MD, graduated with a B.S. in Biomedical Engineering from Washington University in St. Louis. His subsequent training has been at Case Western Reserve University Medical School (M.D.), Lurie Children’s Hospital (pediatric residency), and Children’s Hospital Los Angeles (pediatric critical care fellowship). He was one of the founding members of the PICU Data Collaborative (PDC) when he was an attending physician at Cohen Children’s Medical Center. He joined the VPICU team in 2023 as a scientific and clinical advisor alongside a joint appointment practicing with Cedars-Sinai Medical Center. He currently serves as the physician lead of Data Quality and Harmonization for the PDC, and he is also a Co-Principal Investigator for the ML-ROVER project.
Paul Vee, Enterprise Data Architect
Paul Vee, M.B.A, has been with the VPICU team since 2002. In that span he was the technical lead on two telemedicine grants and developed several web-based applications used in research studies. Currently, Paul serves as the Enterprise Data Architect for CHLA’s Clinical Services. Paul’s main focus is pioneering data infrastructure and software at CHLA and managing the completion of all key objectives ensuring the success of The Laura P. and Leland K. Whittier VPICU.
Alysia Flynn, Senior Data Scientist
Alysia Flynn, Ph.D., is a software development engineer with a Ph.D. in Computer Science and Informatics from Cardiff University. A member of the data systems team, she designs and develops data integration and manipulation processes to support the team’s applications.
Mike Reilly, Software Engineer
Mike Reilly, B.Sc., currently manages the cloud infrastructure and software supporting the data scientists of the VPICU and the PDC. Mike has an extensive background in planning, deploying, and managing public and private cloud environments covering servers, storage, application virtualization, and machine learning. His past work includes managing projects and creating solutions across a diverse background of industries including banking, entertainment, healthcare, and logistics.
Eugene Laksana, Senior Data Scientist
Eugene Laksana, B.Sc., applies machine learning, including deep learning, techniques on 10 years of electronic health records (EHR) to develop algorithms for state-of-the-art clinical decision support. He has vast experience with handling multimodal data and developing ML frameworks. He has worked to develop solutions for many PICU problems such as early prediction of BiPAP failure and predicting time to death after palliative extubation. He has also helped develop and teach a course for CHLA physicians to learn principles of signal detection. Eugene holds. a B.Sc in Computer Science from the University of Southern California. He really likes capybaras.
Ishmael Obeso, Data Scientist
Ishmael Obeso, B.Sc., was previously a neuroscience researcher at UCLA, where he focused on computational neuroscience and brain-machine interfacing. He hopes to use his domain knowledge in neuroscience to further his work as a Data Scientist. Currently, Ishmael is using state-of-the-art ML models, CNNs and spectrograms to detect pathologic breath patterns of children who are invasively ventilated.
Alice Zhou, Data Scientist
Alice Zhou, B.A., specializes in visualization, providing clinicians and data scientists with tools for developing clinical decision support. Alice has worked on various projects at CHLA, such as developing models to help palliative care clinicians and evaluating how different performance assessments methodologies estimate out-of-sample performance. Alice is currently working on a project to predict future creatinine for precision drug dosing. She is a graduate of Wellesley College and holds a Bachelor’s Degree in Media Arts and Sciences.
Ruiqi (Tina) Huang, Data Scientist
Tina Huang, M.Sc., is interested in understanding and solving clinical problems using large-scale data and computational methods. She is currently working on WISE-HARE (use wearable data to identify children with pediatric sleep disorder) and ML-ROVER (reduce laboratory overutilization in critically ill children). In both projects, Tina closely collaborates with different field experts. She has a B.S. and M.S. in Bioengineering and a B.A. in Computer Science and Linguistics from University of California, Los Angeles.
Aleksandra (Sasha) Kretsu, Data Analyst
Sasha Kretsu, B.Sc. works with data scientists within the hospital and clinicians across the country to improve care of critically ill children. She focuses on designing and implementing pipelines that facilitate the submission, harmonization, and quality assurance of multi-institutional EHR data. Sasha leverages her background in economics to bring a unique perspective to the team, enabling her to think critically and deeply about data.
Long V. Ho, Senior Data Scientist
Long Ho, B.Sc., re-joined the VPICU in 2024 and serves as a technical advisor for VPICU projects. He is also working on expanding the VPICU’s Data Science infrastructure stack. During Long’s first stint with the VPICU (2016-2020), he developed a modular framework to munge complex time-series healthcare data and train machine learning and deep learning algorithms for clinical research and applications. Long was trained in physics and math at University of California Los Angeles. Prior to joining the VPICU and CHLA, Long was an experimental physics researcher at UCLA’s Particle Beam Physics Laboratory (PBPL) and Stanford’s National Accelerator Laboratory (SLAC) focusing on modeling and building systems for experimental data collection. Following SLAC, Long joined Arete Associates and utilized his research and mathematical foundations to innovate and apply advanced computational algorithms for defense applications.
VPICU through the years
