Test–retest reliability of the oxygen uptake efficiency slope in surgical patients

Abstract

SummaryThe oxygen uptake efficiency slope is a measure of cardiopulmonary fitness, that can be obtained from a sub-maximal cardiopulmonary exercise test. It has been evaluated in medical patients but its reliability in surgical populations remains uncertain. We conducted a test-retest study with the aim of establishing the reliability of the oxygen uptake efficiency slope in relation to that of the anaerobic threshold and peak oxygen uptake, in general surgical patients. Twenty-six patients over 60 years old completed two symptom-limited, incremental cycle ergometry tests within 7 days. The mean (SD) anaerobic threshold was 13.0 (3.0) mlO 2 .kg )1 .min )1 . There were no significant differences between mean test and retest values of anaerobic threshold (p = 0.50), peak oxygen uptake (p = 0.76) or oxygen uptake efficiency slope (p = 0.42). Reliability coefficients (95% CI) for the anaerobic threshold, oxygen uptake efficiency slope and peak oxygen uptake were 66.7% (45.3-87.9%), 89.0% (81.0-96.9%) and 91.7% (85.7-97.8%), respectively. The oxygen uptake efficiency slope was determined easily in all patients and found to have excellent reliability. Its clinical utility in determining pre-operative fitness warrants further evaluation.

Validity of Reporting Oxygen Uptake Efficiency Slope from Submaximal Exercise Using Respiratory Exchange Ratio as Secondary Criterion

“…Recent OUES literature explores the test-retest validity and functional outcomes in new clinical cohorts reporting favourable results [20, 21]. This is supporting a potential transition in preoperative and respiratory clinical practice to use OUES in preference to the ventilatory anaerobic threshold.…”

An evaluation of the validity of the pre‐operative oxygen uptake efficiency slope as an indicator of cardiorespiratory fitness in elderly patients scheduled for major colorectal surgery

“…It would, therefore, be worthwhile evaluating how useful alternative objective (sub)maximal exercise parameters might be in assessing and predicting prognosis in patients undergoing major surgery. The oxygen uptake efficiency slope has also been found to have excellent test-retest reliability in general surgical patients, with a reliability coefficient (95%CI) of 0.89 (0.81-0.97) [31]. The oxygen uptake efficiency slope concept is based on the curvilinear relationship between the minute ventilation and oxygen uptake throughout an incremental cardiopulmonary exercise test.…”

“…The oxygen uptake efficiency slope has been reported to correlate strongly with well-established measures of cardiorespiratory fitness such as peak oxygen uptake and the ventilatory anaerobic threshold in different groups of adults and children [18][19][20][21][22][23][24][25][26][27][28][29][30]. The oxygen uptake efficiency slope has also been found to have excellent test-retest reliability in general surgical patients, with a reliability coefficient (95%CI) of 0.89 (0.81-0.97) [31]. However, the validity of it as an effort-independent alternative measure of pre-operative cardiorespiratory fitness, and its ability to predict postoperative outcomes, are unknown.…”

Test-Retest Reliability of Maximal and Submaximal Gas Exchange Variables in Patients With Coronary Artery Disease

“…The reliability of some of these submaximal exercise measures was investigated in healthy subjects, 10 patients with CHF, 8 , 11 before major general surgery, 20 and a combined group of patients with CHF, COPD, and valve disease. 13 However, despite the widespread and increased use of these submaximal CPET variables, including patients with CAD, the test-retest reliability of most of these submaximal exercise variables has never been investigated in this population.…”