The significant relationships found between the three exercise tests, and the regression equations predicting peak work rate on the CET from the 6MWT or the ISWT, may allow for the estimation of intensity of cycle exercise training from walk tests in COPD patients.

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For patients who smoke, electronic cigarettes may offer a pathway to achieve tobacco abstinence and reduce the risk of postoperative complications. Clinicians have a pivotal role in supporting smoking cessation by patients with lung cancer and coronary artery disease throughout the perioperative period of cardiothoracic surgery. However, the views of Australian cardiothoracic clinicians on electronic cigarettes and smoking cessation are unknown. Semi-structured interviews were conducted with 52 cardiothoracic surgeons, anaesthetists, nurses and physiotherapists in six hospitals in Sydney and thematically analysed. Clinicians’ knowledge about electronic cigarettes and the regulatory environment surrounding them was limited. Clinicians believed that: electronic cigarettes, though unlikely to be safe, were safer than tobacco cigarettes; electronic cigarettes may have a harm reduction role in public health; and electronic cigarettes were a potential smoking cessation tool for the extraordinary circumstances of surgery. The professional role of a clinician and their views about electronic cigarettes as a perioperative smoking cessation aid had an influence on future clinician-patient interactions. Electronic cigarette use is increasing in Australia and clinicians are likely to receive more frequent questions about electronic cigarettes as a cessation aid. Stronger guidance for clinicians is needed on the topic of electronic cigarettes and cardiothoracic surgery.

BackgroundCycle training intensity for patients with chronic obstructive pulmonary disease (COPD) is normally based on an incremental cycle test. Such tests are expensive and not readily available to clinicians. The six-minute walk test (6MWT) has been proposed as an alternative to an incremental cycle test for this purpose, based on the findings of previous research that the peak oxygen consumption (VO2peak) for the incremental cycle test and the 6MWT was equivalent in participants with COPD. A regression equation relating distance walked on the 6MWT and peak work rate (Wpeak) on the incremental cycle test has been described. The aim of this study is to measure the physiological responses to constant load cycle exercise performed at an intensity of 60% Wpeak determined from the 6MWT in participants with stable COPD.Methods/DesignThis study is a prospective, repeated measures design. Thirty-five participants with stable COPD and mild to severe lung disease will be recruited from referrals to pulmonary rehabilitation. Subjects with co-morbidities limiting exercise performance will be excluded. Two 6MWTs will be performed. The better 6MWT will be used to calculate Wpeak for cycle exercise from a regression equation. After 30 minutes rest, subjects will perform ten minutes of constant-load cycle exercise at 60% of the calculated Wpeak. During all exercise, cardiorespiratory and metabolic data (Cosmed K4b2), dyspnoea and rate of perceived exertion (RPE) will be recorded. The VO2 measured at the end of cycle exercise will be compared to VO2peak of the 6MWT (VO2bike/VO2walk). Pearson's correlation coefficient will be calculated for the relationship between VO2bike and VO2walk. A one-way analysis of variance (ANOVA), with Bonferroni correction, will be performed to determine whether the ratio of VO2bike/VO2walk is affected by disease severity.DiscussionThis novel study will measure the physiological responses to cycle exercise, in terms of VO2peak, performed at an intensity determined from the 6MWT in participants with COPD. Positive findings will enable clinicians to more precisely prescribe cycle training intensity by utilising a simple, reliable and inexpensive 6MWT, thus providing a better standard of care for patients with COPD referred to pulmonary rehabilitation.Trial RegistrationACTRNO12606000496516

Background: Prescription of an appropriate exercise training intensity is critical to optimise the outcomes of pulmonary rehabilitation; however, prescribing cycle ergometry training is challenging if peak work is unknown. Recently two studies reported regression equations which allow estimation of peak cycle work rate from the 6-minute walk distance (6MWD) in chronic obstructive pulmonary disease (COPD). Objectives: To compare estimates of peak work and target training work rate (60% peak) obtained from these equations. Methods: Sixty-four (38 male) subjects, mean ± SD age 70 ± 8 years and FEV₁ 49 ± 18% predicted with COPD performed the 6-minute walk test according to a standardised protocol. Estimates of peak work were obtained using the published equations and agreement was examined using Bland and Altman plots. Results: Mean 6MWD was 376 ± 86 m compared to 464 ± 110 m and 501 ± 83 m in samples used to derive the equations. There was substantial variation in estimates of peak work between equations (range 1–75 Watts difference) with a coefficient of variation of 35%. Differences were greater in men than in women (p < 0.001). The Luxton equation predicted higher peak work than the Hill equation in younger subjects and at work rates over 50 Watts. Estimated training work rate differed by more than 20 Watts in 18 subjects (28%). Conclusions: This comparison of reference equations for predicting peak cycle work rate from 6MWD indicates substantial variation between methods that differs systematically across the range of work rates. Further research is required to validate the equations and assess their utility for exercise prescription in pulmonary rehabilitation.