The Steep Ramp Test as Precursor to Assess Physical Fitness before Esophagectomy in Cancer Patients

Maximum oxygen uptake (VO2max) is a predictor for postoperative complications after esophagectomy. Cardiopulmonary exercise test (CPET) is the golden standard for measuring VO2max. The alternative steep ramp test (SRT) is less strenuous with several benefits, providing an estimation of VO2max. This study aimed to determine whether SRT is a reliable alternative for CPET to evaluate preoperative fitness.

A total of 113 patients were included in this study. The agreement between SRT and CPET was analyzed using a t test, Intraclass correlation coefficient (ICC), and the Bland-Altman analysis. The threshold for adequate preoperative fitness was set at 17.0 mL/kg/min.

The mean difference between CPET and SRT was 2.77 mL/kg/min (95% confidence interval [CI]: 2.14-3.41). The ICC was 0.79 (95% CI: 0.70-0.85). The upper limit of agreement of the Bland-Altman was 9.44. The addition of 9.44 to the CPET threshold gives an SRT threshold of 26.44 mL/kg/min. Thirty-one (27.4%) patients scored higher than the SRT threshold.

The SRT VO2max differs from VO2max as measured by CPET. However, the difference was found to be clinically irrelevant for a substantial portion of patients. Hence, SRT is a promising alternative to CPET for determining physical fitness and might render CPET obsolete for fit individuals.