LAUSR

Introduction: Cardio-pulmonary Exercise Testing (CPET) is used for diagnosis and monitoring of cardiovascular and respiratory conditions in children. There are several reference values published for CPET. Despite this, the most commonly used in paediatric labs in the UK are from Cooper et al in 1984. Up-to-date values have been published since this which may be more applicable and valid to the current population. Objectives: We aimed to compare 3 sets of reference equations for maximal oxygen uptake (VO22peak) in children to see if there were any clinical differences depending on which equation was used. We hypothesized that there would be significant differences between the reference sets. Methods: We reviewed data from our CPET database to look at predicted values for VO2peak using Cooper 1984 (CO), Bongers 2012 (BO) and Blanchard 2018 (BL). Predicted VO2peak was calculated for each reference equation and the % predicted was compared using Bland Altman analysis. Results: There were 766 subjects - 431 males. Age range was 5 -18 years. Table 1 shows the mean bias with ULOA and LLOA for each of the comparisons of % predicted. A reduced VO2peak was found in 49%, 69% & 70% for CO, BO and BL respetively. Conclusion: The choice of reference values used for CPET in children will significantly affect whether the results are deemed normal. 3 of the commonly used equations show large limits of agreement. The most recent values by Blanchard look promising as they use a corrected bodyweight, height, age and sex and have published Z scores with the data. The main drawback is they only start from 12 years onwards.