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Background Accurate assessment of functional capacity, a predictor of postoperative morbidity and mortality, is essential to improving surgical planning and outcomes. We assessed if all 12 items of the Duke Activity Status Index (DASI) were equally important in reflecting exercise capacity. Methods In this secondary cross-sectional analysis of the international, multicentre Measurement of Exercise Tolerance before Surgery (METS) study, we assessed cardiopulmonary exercise testing and DASI data from 1455 participants. Multivariable regression analyses were used to revise the DASI model in predicting an anaerobic threshold (AT) >11 ml kg−1 min−1 and peak oxygen consumption (VO2 peak) >16 ml kg−1 min−1, cut-points that represent a reduced risk of postoperative complications. Results Five questions were identified to have dominance in predicting AT>11 ml kg−1 min−1 and VO2 peak>16 ml.kg−1min−1. These items were included in the M-DASI-5Q and retained utility in predicting AT>11 ml.kg−1.min−1 (area under the receiver-operating-characteristic [AUROC]-AT: M-DASI-5Q=0.67 vs original 12-question DASI=0.66) and VO2 peak (AUROC-VO2 peak: M-DASI-5Q 0.73 vs original 12-question DASI 0.71). Conversely, in a sensitivity analysis we removed one potentially sensitive question related to the ability to have sexual relations, and the ability of the remaining four questions (M-DASI-4Q) to predict an adequate functional threshold remained no worse than the original 12-question DASI model. Adding a dynamic component to the M-DASI-4Q by assessing the chronotropic response to exercise improved its ability to discriminate between those with VO2 peak>16 ml.kg−1.min−1 and VO2 peak Conclusions The M-DASI provides a simple screening tool for further preoperative evaluation, including with cardiopulmonary exercise testing, to guide perioperative management.

Background Cardiopulmonary exercise testing (CPET) measures peak exertional oxygen consumption ( V ˙ O 2 peak ) and that at the anaerobic threshold ( V ˙ O 2 at AT, i.e. the point at which anaerobic metabolism contributes substantially to overall metabolism). Lower values are associated with excess postoperative morbidity and mortality. A reduced haemoglobin concentration ([Hb]) results from a reduction in total haemoglobin mass (tHb-mass) or an increase in plasma volume. Thus, tHb-mass might be a more useful measure of oxygen-carrying capacity and might correlate better with CPET-derived fitness measures in preoperative patients than does circulating [Hb]. Methods Before major elective surgery, CPET was performed, and both tHb-mass (optimized carbon monoxide rebreathing method) and circulating [Hb] were determined. Results In 42 patients (83% male), [Hb] was unrelated to V ˙ O 2 at AT and V ˙ O 2 peak (r=0.02, P=0.89 and r=0.04, P=0.80, respectively) and explained none of the variance in either measure. In contrast, tHb-mass was related to both (r=0.661, P

Background Perioperative beta-blockade is widely used, especially before vascular surgery; however, its impact on exercise performance assessed using cardiopulmonary exercise testing (CPET) in this group is unknown. We hypothesized that beta-blocker therapy would significantly improve CPET-derived physical fitness in this group. Methods We recruited patients with abdominal aortic aneurysms (AAA) of

† Cardiopulmonary exercise testing by cycle ergometry has limited utility as a preoperative assessment tool in patients with lower limb dysfunction. † Leg ergometry was compared with arm ergometry in vascular surgery and healthy patients. † Oxygen uptake using the two methods was correlated, but arm ergometry was a poor predictor of leg ergometry. † Further study is required to establish the perioperative utility of arm ergometry. Background.Cardiopulmonaryexercisetestingbycycleergometry(CPETleg)isanestablished assessmenttoolofperioperativephysicalfitness.CPETutilizingarmergometry(CPETarm)isan attractive alternative in patients with lower limb dysfunction. We aimed to determine whether oxygen uptake ( ˙ Vo2) obtained by CPETleg could be predicted by using CPETarm alone and whether CPETarm could be used in perioperative risk stratification. Methods. Subjects underwent CPETarm and CPETleg. To evaluate the ability of ˙ Vo2 obtained from CPETarm to predict ˙ Vo2 from CPETleg, we calculated prediction intervals (PIs) at lactate threshold ( ˆ uL) and peak exercise in both groups. Receiver operating characteristic (ROC) curves were used to risk stratify patients into high and low categories based on published criteria. Results. We recruited 20 vascular surgery patients (17 males and three females) and 20 healthy volunteers (10 males and 10 females). In both groups, PIs for ˙ Vo2 at ˆ uL and peak were wider than clinically acceptable (patient group— ˙ Vo2 at ˆ uL CPETarm ranged from 55% to 108% of CPETleg and from 54% to 105% at peak; healthy volunteers—37‐77% and 41‐79%, respectively). The area under the ROC for CPETarm ˙ Vo2 in patients was 0.84 [95% confidence interval (CI): 0.66, 1.0] at ˆ uL, and 0.76 (95% CI: 0.54, 0.99) at peak. Conclusions.Althougharelationshipexistsbetween ˙ Vo2 valuesforCPETarmandCPETleg,this