None listed
Conditions
Brief summary
Many of us will require a major operation during our lifetime. Complications after surgery are common, and medical staff continue to explore ways to reduce this. Although many risk factors, such as our health problems and the operation required cannot be changed, it has been demonstrated that we can improve fitness over 4-6 weeks before surgery. In our first study, we have achieved a greater than 10% improvement in fitness before surgery. In this study, we will examine what an ideal aerobic preoperative exercise program, including for patients with different levels of fitness, should look like. This study will compare two groups of participants, a high risk and an average risk group, who are scheduled for abdominal surgery. Fitness, defined as peak oxygen consumption (peak VO2), will be measured by cardiopulmonary exercise testing (CPET). The exercise program will include 14 sessions over four weeks (12 sessions and two CPET). The changes in peak VO2 will be compared against the number of exercise sessions to construct ‘dose-response’ curves, which will be used to recommend evidence-based preoperative exercise programs for both average and high-risk patients. Postoperative outcomes including complications, recovery from surgery, and quality of life will also be compared.
Interventions
A full pre-operative anaesthetic assessment will be performed for each participant, and this is part of the standard treatment that they receive if they are patients scheduled for abdominal surgery. Participants will be categorised as either fit or unfit, by means of the Duke Activity Survey, initial cardiopulmonary exercise testing (CPET), and a modified frailty index. CPET will be performed on an electromagnetically braked ergometer using individualised stepped protocols based on the individual’s fitness levels. This will be supervised by a senior researcher with medical staff also on site. Peak VO2, anaerobic threshold, respiratory exchange ratio and the workloads required to elicit 60% and 90% maximal heart rate will be documented. CPET will be repeated throughout the exercise program to test for changes in Peak VO2. Participants will be randomised to standard care or to 8-14 sessions of high intensity interval training (HIIT) training lasting approximately 30 minutes each (either home-based, in a clinical setting, or at a community gym). Patients in the HIIT treatment arms will undergo approximately three supervised exercise sessions a week. Each session will begin and end with 5 minutes of cycling against a light load. The high intensity protocol is based around ten one-minute intervals of higher intensity exercise alternating with one-minute periods of lower intensity cycling. The objective is to reach 90% of the maximal heart rate (as identified on CPET) during the periods of intense exercise. Clinical setting training sessions will be performed at Dunedin Hospital in an approved exercise unit under the supervision of a certified exercise physiologist and another investigator or student involved in this study. The community setting arm will involve patients exercising individually or in a group co-ordinated by a fitness trainer with some experience in coaching/exercise training (This will be either an employee of a fitness centre who leads training sessions, or an exercise physiologist). This will take place at a local community-focused facility. The home based training setting will involve Stationary bicycles (Monark Ergomedic 828E) being provided for individual participants in their homes, as in previous studies conducted by one of our team members. Participants will attend a one-hour session with an exercise physiologist who will familiarise them with the training protocol. Use of the heart rate monitor and paired device (watch or phone, provided at the participant’s preference) will be demonstrated during this training session. The participant will train during this session so that they understand what exertion feels like at 90% of their maximum heart rate (or a 15 out of 20 on the BORG17 scale). This is important for participants who are on beta-blockers, and also if the heart rate monitor or paired device fails during a session. Participants will be encouraged to train three times a week, with the objective of achieving 10 minutes of intense exercise aiming to reach 90% of their maximum heart rate as identified with CPET, as per our previously outlined protocol. The participant will upload heart rate data to the Polar Flow website, which will be accessible to study investigators. Heart rate and interval duration are recorded and displayed so that each session can be remotely monitored. The research assistant or physiologist will contact the participant twice a week to check on heart rate targets, to advise on adjustments of exercise intensity and duration of intense intervals. The duration of the exercise period is for 14 sessions, with the aim of this being achieved in four weeks, but may extend to six weeks if the patient misses a session.
Sponsors
Dunedin Hospital
Study design
Allocation
Non-randomised trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Investigator)
Eligibility
Sex/Gender
All
Age
55 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
One of the following: 1.) Patients on the surgical waiting list for the following elective operative procedures: major bowel surgery, incisional hernia repair, cholecystectomy, hysterectomy and prostate surgery. 2.) Patients referred by a cardiologist, respiratory physician or geriatrician. Participants must be able to attend multiple supervised exercise sessions at the hospital and be identifiable from surgery waiting lists approximately two months before the estimated time of surgery.
Exclusion criteria
1) Inability to perform CPET, 2) Contraindication to exercise diagnosed on CPET, 3) Uncontrolled hypertension (Blood Pressure >180/100), 4) Active clinical angina (This does not include patients with a history of ischaemic heart disease who have no symptomatic angina on appropriate medical treatment or no angina following a successful revascularization procedure), 5) myocardial infarction in the past three months, 6) uncontrolled cardiac arrhythmias, 7) aortic aneurysm >6.5cm, 8) severe obstructive pulmonary disease with a FEV1 < 1.0 litres, 9) inability to provide consent, 10) Preoperative chemotherapy or radiotherapy which overlaps with the period of preoperative exercise. 11) Anaemia, with an Iron infusion planned to be given during the period of preoperative exercise 12) Participants already participating in an aerobic exercise training programme similar to HIIT training (high intensity for more than ten minutes, more than three times per week)
Outcome results
None listed