Reference values and web-based tool for intraoperative heart rate and blood pressure in paediatric patients undergoing general anaesthesia for noncardiac procedures

BACKGROUND: Heart rate (HR) and arterial blood pressure (BP) monitoring is standard of care during paediatric anaesthesia, yet evidence-based reference values for anaesthetised children remain limited. Existing BP reference values do not account for the combined effects of age, sex, weight, and height, and HR reference values in this population are lacking. METHODS: We conducted a retrospective multicentre study using data from the Multicenter Perioperative Outcomes Group anaesthesia registry (2016-22). Included patients were aged <18 yr, ASA physical status 1 or 2, and undergoing noncardiac procedures under general anaesthesia. We used quantile regression to model the 2.3rd, 16th, 50th, 84th, and 97.7th centiles for HR, mean arterial pressure (MAP), systolic BP, and diastolic BP at two time points: the preparation phase (end of induction) and surgical phase (15-35 min after procedure start). Model covariates included age, sex, weight, and height. We selected the best model for each outcome using cross-validation with pinball loss. RESULTS: A total of 284 385 patients from 57 institutions were analysed. Optimal model complexity varied by outcome: a two-way interaction model was selected as the best-performing model for preparation phase HR and surgical phase MAP. A three-way interaction model was selected as the best-performing model for the remaining outcomes. Comprehensive prediction tables and an interactive web-based tool were developed for all outcomes. CONCLUSIONS: This study provides integrated HR and BP reference values for healthy paediatric patients undergoing general anaesthesia, incorporating age, sex, weight, and height simultaneously. These reference values with an interactive website can support clinical decision-making and haemodynamic monitoring.