The PREBEAT Trial: Digital PREhaBilitation in thE Cardiac Surgical populATion

mAUQ is an 18-item questionnaire for patients to evaluate the usability of the digital application under the three domains of; Ease of Use, Interface, Satisfaction and Usefulness.

Low numbers indicate a higher perception of usability with the digital interface for participants.

Metrics Used include

• Time and date: when the application is accessed.
• Dwell Time: how much time is spent on a particular page.
• Number of pages viewed: how many views per page per day.
• User input data: data the user submits in the app, including minutes walked, exercises marked as complete, and questionnaires completed.

TFA-Q is composed of eight items, in alignment with the eight acceptability constructs (Affective attitude, Burden, Ethicality, Perceived effectiveness, intervention coherence, self-efficacy, opportunity costs, general acceptability).

High numbers indicate a more acceptable digital experience.

Adverse events, defined as any undesirable event, such as injury, fall, and discomfort related to prehabilitation will be recorded and severity will be reported according to hospital policy.

Lower numbers are more favourable, indicating fewer adverse events.

Hospital services use measured by length of stay (LOS) (days) - gained using hospital administrative data.

Low numbers are preferable, indicating the patient has not stayed as long in hospital.

Hospital services use as measured by ICU LOS (days), gained using hospital administrative data.

Low numbers are preferable, indicating the patient has not required as intensive care.

Mortality as measured by days alive out of hospital. This data will be gained using hospital administrative records in the event that the patient is uncontactable.

DAoH should be equal to the number of days since discharge. Where DAoH are lower than the number of days since discharge, this is less favourable, indicating the patient has not survived.

Hospital services use as measured by the incidence of Readmissions, gained using hospital administrative data.

Low numbers are preferable, indicating the patient has had less need to return to hospital for care, following discharge.

The HUQ is 12 item survey which assesses the frequency and type of healthcare services accessed by individuals. It gathers data on medical visits, hospital stays, medication use, and other healthcare interactions to evaluate healthcare consumption, and includes modern communication systems of engaging with health care services.

Low numbers are preferable, indicating less need to engage with health services.

Hospital administrative records will be used to supplement resource use data from surveys on consent from participants. In addition, the lead patient-facing researcher will maintain a clinician log, documenting time spent with each patient during the intervention phase to accurately represent the equivalent cost of the intervention. This is expected to include time used for adjusting or maintaining physical activity programs, and any interactions online, via phone, or telehealth. Cost of program delivery will be calculated on conclusion of the PREBEAT trial.

Low cost is preferable, indicating a potential financial benefit to health services which provide prehabilitation programs.

Recovery will be assessed using the 5-domain the Post-Operative Quality of Recovery Scale (PostopQRS). This scale has been designed to quantify quality of recovery ((physiological, emotive, nociceptive, activities of daily living, cognitive and patient perspective) after surgery and anaesthesia. It is comprised of questions that objectively measure patient recovery over multiple time periods. This assessment has been validated and used extensively in the cardiac surgical population. The PostopQRS will be used to monitor multidomain recovery at pre and post intervention timepoints, postoperatively and throughout recovery.

The Functional Difficulties Questionnaire shortened (FDQs) is a 10-item functional outcome measure which asks the participant to rate the difficulty they experience when completing a series of 10 upper limb and trunk activities by placing a mark along a 10cm line, with anchors indicating "no difficulty" and "maximum difficulty". For those activities that participants could not attempt whilst completing the questionnaire due to the institution sternal precautions, they are asked to think back to the last time they performed the task.

Individual scores, measured to the nearest centimetre (cm), are aggregated to form a total out of 130 with higher scores representing greater difficulty experienced during functional activities.

Height (cm) and weight (kg) are taken and placed into the formula: BMI = weight (kg) / [height (m)]². BMI healthy range is 18.5-24.9, with patients being above this overweight (or obese if over 30).

The Melbourne Group Score (MGS) is a clinical tool used to diagnose postoperative pulmonary complications (PPCs) in patients following surgery. It consists of a set of criteria including abnormal chest x-ray, fever, elevated white cell count, production of purulent sputum, positive respiratory culture, oxygen saturation below 90% on room air, and clinical signs of pulmonary infection.

If a patient has the presence of four or more criteria in a 24-hour period it is diagnostic of a PPC.

Lower numbers of PPC through the study are preferable, indicating a lower number of chest infections.

The 1-Minute Sit-to-Stand (1STS) assessment is a simple, quick test used to evaluate lower body strength, endurance, and functional capacity. The participant is asked to stand up from a seated position and sit back down as many times as possible within one minute. The total number of repetitions is recorded as the score.

Higher scores indicate a better functional capacity.

Maximal Inspiratory Pressure (MIP) is a measure of inspiratory muscle strength and will be measured via a maximal inspiratory effort using the Powerbreathe KH2. Patients will be asked to sit comfortably in a chair with their feet flat on the ground, with a nose clip on. Patient's will be asked to completely exhale, then form a secure lip seal around the mouthpiece and inhale as forcefully as possible through the device. The KH2 Powerbreathe will measure the pressure generated during this maximal inspiratory effort. This process will be repeated twice, with a 1-minute rest between efforts. The highest pressure generated will be recorded as the patient's MIP.

Higher pressures are preferable, indicating stronger inspiratory muscles.

The MEDAS (Mediterranean Diet Adherence Screener) is a 14-item questionnaire designed to evaluate adherence to the Mediterranean diet. Each item assesses the frequency or amount of specific food consumption or dietary habits associated with the Mediterranean diet, such as olive oil, fruits, vegetables, nuts, fish, legumes, and wine. Points are assigned for each item, with higher scores indicating greater adherence to the diet.

The State-Trait Anxiety Inventory (STAI) is a 40 item psychological assessment tool that measures anxiety in adults and is commonly used in prehabilitation research. It distinguishes between two types of anxiety: state anxiety (a temporary condition experienced in specific situations) and trait anxiety (a general tendency to respond with anxiety across many situations). To reduce the patient assessment burden, the shorted version: State-Trait Anxiety Inventory (STAI-6) will be used in this study.

Lower scores are preferable, indicating a less anxious patient.

The General Self-Efficacy Scale (GSE) is a 10-item questionnaire designed to assess an individual's belief in their ability to handle various stressful situations and challenges. Each item is rated on a 4-point Likert scale, ranging from "Not at all true" to "Exactly true." Higher scores indicate greater self-efficacy.