Cardiopulmonary Exercise Test Data Averaging Methods and Preoperative Risk Assessment

Cardiopulmonary exercise testing (CPET) is used for preoperative risk assessment in patients with colorectal cancer who need to undergo surgery. For presentation and interpretation purposes, CPET data are averaged by using a time- or breath-based average. It is uncertain to what extent differences in data averaging methods influence the numerical value of preoperative CPET-derived variables used for risk assessment. Therefore, the primary aim of this study is to investigate the influence of different CPET data averaging intervals on the numerical values of CPET-derived variables used for preoperative risk assessment in patients scheduled for elective colorectal cancer surgery. The secondary aim is to elucidate the impact of data-averaging intervals on classification of patients into a low- or high-risk category for postoperative complications based on known risk assessment thresholds.