Development of Normative Ranges for Vital Signs and Differentiation by American Society of Anesthesiologists Physical Status Category: A Retrospective Observational Study.

Normative ranges for vital signs under general anesthesia are well established for healthy pediatric patients, but the influence of The American Society of Anesthesiologists Physical Status (ASA-PS) classification on these normative ranges remains unexplored. The purpose of this study is to develop age-based normative ranges for heart rate (HR) and blood pressure (BP) in patients undergoing general anesthesia for noncardiac surgery in our institution and assess differences by ASA-PS classification. This is a retrospective observational single-center study. We reviewed all anesthetic records from the Hospital for Sick Children, Canada between March 1st and December 31st, 2023. We extracted physiological data from our in-house high-resolution physiological data repository (AtriumDB) to develop normative ranges for physiological parameters and compared them according to ASA-PS classification. We developed age-based normative ranges for BP and HR. We found significant differences between ASA-PS groups, most notably between ASA-PS 1 and 5. We found a statistically significant difference between ASA-PS 1-2 and 3-5 across all physiological parameters. This study validates existing pediatric anesthesia reference ranges while demonstrating the feasibility of incorporating patients across the spectrum of ASA-PS. Further multicenter studies are needed to generalize these findings.