The use of perioperative cardiopulmonary exercise testing (CPET) to evaluate the risk of adverse perioperative events and inform the perioperative management of patients undergoing surgery has increased over the last decade. CPET provides an objective assessment of exercise capacity preoperatively and identifies the causes of exercise limitation. This information may be used to assist clinicians and patients in decisions about the most appropriate surgical and non-surgical management during the perioperative period. Information gained from CPET can be used to estimate the likelihood of perioperative morbidity and mortality, to inform the processes of multidisciplinary collaborative decision making and consent, to triage patients for perioperative care (ward vs critical care), to direct preoperative interventions and optimization, to identify new comorbidities, to evaluate the effects of neoadjuvant cancer therapies, to guide prehabilitation and rehabilitation, and to guide intraoperative anaesthetic practice. With the rapid uptake of CPET, standardization is key to ensure valid, reproducible results that can inform clinical decision making. Recently, an international Perioperative Exercise Testing and Training Society has been established (POETTS www.poetts.co.uk) promoting the highest standards of care for patients undergoing exercise testing, training, or both in the perioperative setting. These clinical cardiopulmonary exercise testing guidelines have been developed by consensus by the Perioperative Exercise Testing and Training Society after systematic literature review. The guidelines have been endorsed by the Association of Respiratory Technology and Physiology (ARTP).

In this article, we review the evidence underpinning the broader prehabilitation concept and the target behavioural and lifestyle risk factors including their perioperative impact and evidence for prehabilitation intervention. We also identify principles for delivering prehabilitation in practice, alongside lessons for the perioperative setting from well-established allied interventions; cardiac and pulmonary rehabilitation.

SummaryDespite calls for the routine implementation of pre-operative exercise programmes to optimise patient fitness before elective major surgery, there is no practical guidance for providing safe and effective exercise in this specific context. The following clinical guideline was developed following a review of the evidence on the effects of pre-operative exercise interventions. We developed a series of best-practice and, where possible, evidence-based statements to advise on patient care with respect to exercise training in the peri-operative period. These statements cover: patient selection for exercise training in surgical patients; integration of exercise training into multi-modal prehabilitation programmes; and advice on exercise prescription factors and follow-up. Although we acknowledge that further research is needed to identify the optimal exercise prescription in different clinical scenarios, we urge peri-operative teams to make use of these recommendations. Summary of key recommendations1 Pre-operative exercise training should be offered to patients scheduled for major or complex elective surgery with a view to improving their physical fitness and health status and reducing the risk of peri-operative morbidity and mortality. If resources are limited, priority of referral to preoperative exercise training should go to patients who are at increased risk of peri-operative complications, such as those with low cardiorespiratory fitness.2 Pre-operative exercise training should be offered as part of a multi-modal prehabilitation programme that addresses a variety of peri-operative risk factors including cigarette smoking, excessive alcohol consumption, and anaemia. 3 Healthcare professionals making referrals to a preoperative exercise programme should have basic knowledge about what the programme entails and its potential effects. A pre-operative exercise programme should be presented to the patient by the referring clinician as a fundamental part of their 750

BackgroundEvidence is limited for the effectiveness of interventions for survivors of critical illness after hospital discharge. We explored the effect of an 8-week hospital-based exercise-training programme on physical fitness and quality-of-life.MethodsIn a parallel-group minimized controlled trial, patients were recruited before hospital discharge or in the intensive care follow-up clinic and enrolled 8–16 weeks after discharge. Each week, the intervention comprised two sessions of physiotherapist-led cycle ergometer exercise (30 min, moderate intensity) plus one equivalent unsupervised exercise session. The control group received usual care. The primary outcomes were the anaerobic threshold (in ml O2 kg−1 min−1) and physical function and mental health (SF-36 questionnaire v.2), measured at Weeks 9 (primary time point) and 26. Outcome assessors were blinded to group assignment.ResultsThirty patients were allocated to the control and 29 to the intervention. For the anaerobic threshold outcome at Week 9, data were available for 17 control vs 13 intervention participants. There was a small benefit (vs control) for the anaerobic threshold of 1.8 (95% confidence interval, 0.4–3.2) ml O2 kg−1 min−1. This advantage was not sustained at Week 26. There was evidence for a possible beneficial effect of the intervention on self-reported physical function at Week 9 (3.4; −1.4 to 8.2 units) and on mental health at Week 26 (4.4; −2.4 to 11.2 units). These potential benefits should be examined robustly in any subsequent definitive trial.ConclusionsThe intervention appeared to accelerate the natural recovery process and seems feasible, but the fitness benefit was only short term.Clinical trial registrationCurrent Controlled Trials ISRCTN65176374 ().

Despite the intensity of exercise being generally lower than intended, the findings support the feasibility and acceptability of both preoperative HIT and the trial procedures. A definitive trial is warranted. Registration number: ISRCTN09433624 ( https://www.isrctn.com/).

The small mean benefit was lower than the MCID. However, the marked variability in the individual patient responses revealed that a proportion of patients did benefit clinically, with an estimated NNT of 5.

Patients who survive critical illness often report deterioration in health related quality of life. This has not been shown to improve following post-intensive care unit (ICU) self-directed exercise. The Post Intensive Care eXercise (PIX) study demonstrated improved objectively measured fitness following a supervised exercise programme following critical illness and also suggested beneficial effects on physical and mental health. The qualitative arm of the PIX study reported here utilised focus groups to explore in more detail recovery from critical illness, quality of life following hospital discharge, perceptions of the exercise programme and it's impact on perceived well-being. Sixteen participants (eight of whom underwent the supervised exercise programme) were allocated to four psychologist lead focus groups. Themes identified after hospital discharge centred on social isolation, abandonment, vulnerability and reduced physical activity. However, patients in the exercise group described exercise training as motivating, increasing energy levels and sense of achievement, social interaction and confidence. This study adds to the sparse literature on the patient experience post critical illness. It supports the improvements in physical and mental health suggested with exercise in the PIX study and would support further research in relation to the effects of supervised exercise and rehabilitation programmes post critical illness. It recommends that future comparative outcome studies in this patient population also include interview-based assessment as part of assessment of quality of life and an individual's functional status.

Patients walking >563 m in the 6MWT do not routinely require CPET; those walking <427 m should be referred for further evaluation. In situations of 'clinical uncertainty' (≥427 but ≤563 m), the number of clinical risk factors and magnitude of surgery should be incorporated into the decision-making process. The 6MWT is a useful clinical tool to screen and risk stratify patients in departments where CPET is unavailable.