Development of reference ranges of vital signs in UK children: comparison with international centiles

BackgroundChildren and Young People (CYP) with acute illness require routine assessment of their physiological observations. There is no agreement as to what the standard reference ranges of vital signs in children and young people are. Existing reference ranges of vital signs that are currently used in clinical practice are minimally supported by empirical evidence. They are also sometimes conflicting. MethodsWe conducted a cross-sectional study using 66356 admission episodes to analyze routinely collected age-specific respiratory rate, heart rate, and blood pressure observations of CYP aged 0-19 years old at hospital discharge. Quantile regression with Restricted Cubic Splines was used to model age-specific centiles. These were then compared with standard reference ranges and literature. ResultsNew centile charts for vital signs are presented. Advanced Paediatric Life Support (APLS, 6th Ed.) reference ranges for respiratory rate and blood pressure poorly aligned to the centiles derived in this study although the centiles for heart rate align well. Variance was also demonstrated between the study centiles and those from the clinical papers, with the greatest differences seen in the upper centiles. Similarly, in comparison with APLS reference ranges, heart rate showed best alignment. ConclusionsThis is the first-time physiological observations of CYP in a UK Childrens hospital have been described and centile charts developed. Current widely used reference ranges especially those for Heart Rate and Respiratory Rate are not fit for purpose when evaluating whether the vital signs of a child are normal or otherwise.