Ari completed medical school at the University of Alberta in 1987, specializing in Pediatrics (1992) and Pediatric Infectious Diseases (1994) at the University of Calgary, and Pediatric Critical Care Medicine (1995) at the University of Toronto, in Canada. He has been practicing Pediatric Critical Care at the Stollery Children's Hospital, University of Alberta, since 1995, until recently retiring from PICU in June 2026. He is a Clinical Professor in the Department of Pediatrics and the John Dossetor Health Ethics Center at the University of Alberta. He is the current medical lead of the Complex Pediatric Therapies Follow-up Program, aiming (for the past 26 years) at determining long-term neurodevelopmental, neurocognitive, and functional outcomes of the highest risk survivors of Pediatric Critical Care, and identifying potentially modifiable acute-care predictors to iteratively improve care and outcomes over time. His other research interests have been participation in multicenter RCTs (with the Canadian Critical Care Trials Group, and others) and single center studies. He has contributed to biomedical ethics literature, for example, in arguing that brain death is not the biological death of the human organism, and that non-human animal research is both not morally permissible and in principle will not translate to human benefit. From these research activities he has more than 200 peer-reviewed publications. His perspective on the ventilation of infants with established severe BPD is that of a pediatric intensivist, who clinically cares for these children after they transfer from NICU into the PICU.