Digitally Supported Prehabilitation Before Major Visceral Cancer Surgery

Major visceral oncologic surgery is associated with high postoperative morbidity, prolonged hospitalization, delayed recovery, and reduced quality of life. Patients undergoing surgery of the pancreas, liver, bile ducts, stomach, or esophagus frequently present with reduced physical fitness, malnutrition, sarcopenia, and psychological distress, all of which may negatively affect surgical outcomes and rehabilitation. Although prehabilitation has shown potential to improve functional capacity before surgery, structured prehabilitation pathways are currently not routinely implemented in Austria, and the feasibility of digitally supported perioperative care pathways remains insufficiently evaluated. The aim of the Prehab2Rehab-OncoVis study is to evaluate the feasibility, acceptability, and safety of a multimodal, digitally supported prehabilitation intervention for patients undergoing major visceral oncologic surgery with curative intent. The study will additionally explore potential effects on clinical recovery, functional capacity, rehabilitation outcomes, and patient-reported outcomes across the perioperative pathway. Prehab2Rehab-OncoVis is designed as a prospective, single-arm feasibility cohort study conducted at the University Hospital Salzburg and the University Institute of Sports Medicine, Prevention and Rehabilitation, coordinated by the Paracelsus Medical University in cooperation with the Ludwig Boltzmann Institute for Rehabilitation Research and the Ludwig Boltzmann Institute for Digital Health and Prevention within the Prehab2Rehab consortium. Approximately 30 adult patients, with the possibility to include up to 50 participants if feasible, will be consecutively recruited. The intervention consists of a four-week multimodal prehabilitation program combining supervised exercise training, promotion of physical activity, nutritional counseling, psycho-oncological distress screening, and health literacy support. Digital tools will support the intervention throughout the perioperative pathway, including the HERO application (Das Herz Reha-Informationstool) for patient education and health literacy, aktivplan as a digital exercise planner and training diary, and the CAATS telecommunication platform for remote supervision and tele-prehabilitation sessions where appropriate. The exercise intervention includes supervised center-based sessions and, for participants with longer travel distances, a hybrid model combining center-based and tele-prehabilitation sessions. Nutritional counseling will follow current European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines and includes screening for malnutrition risk. Psycho-oncological distress screening will follow recommendations of the German Cancer Society and includes referral to supportive care when clinically indicated. Participants will be assessed throughout the perioperative pathway, including at the beginning and end of prehabilitation (Prehabilitation Assessment 1 \[PRE1\] and Prehabilitation Assessment 2 \[PRE2\]), during hospitalization and rehabilitation, and at a three-month follow-up after surgery. Primary outcomes focus on feasibility, including recruitment and retention rates, adherence, fidelity, safety, data management feasibility, and acceptability and usability of the digital technologies. Secondary outcomes include clinical recovery indicators, postoperative complications, length of hospital and intensive care stay, functional independence, psychological well-being, quality of life, body composition, cardiorespiratory fitness, functional exercise capacity, and muscle strength. To contextualize outcomes, two historical comparator cohorts will be used: a local hospital cohort of patients who previously underwent similar surgery without prehabilitation, and a national rehabilitation cohort derived from routine rehabilitation datasets matched for diagnosis, sex, and age. The study is intended to generate feasibility data and preliminary estimates that may support the development of future adequately powered randomized controlled trials evaluating digitally supported prehabilitation and rehabilitation pathways in visceral oncologic surgery.

Inclusion Criteria: * Adults aged 18 years or older * Clinical diagnosis requiring major surgery of the pancreas, liver, bile ducts, stomach, or esophagus with curative intent * Confirmed indication for surgery by the multidisciplinary tumor board * Medical stability and physician clearance to participate in a prehabilitation exercise program * Willingness and ability to attend center-based prehabilitation exercise sessions three times per week, or once per week with additional tele-prehabilitation if travel time exceeds 40 minutes one way * Willingness and ability to perform home-based physical activities * Sufficient German language proficiency and digital literacy * Access to a smartphone or tablet device with internet connection * Provision of written informed consent Exclusion Criteria: * Age younger than 18 years * Physical disability or mental impairment preventing safe participation in the study * Health care medical power of attorney not permitting independent consent * Non-elective, emergency, or revision surgery * Acute medical condition contraindicating participation in a structured prehabilitation program