Piloting Prehabilitation Before Abdominal Surgery

Background: Frail Veterans are at increased risk for poor surgical outcomes. Although surgeons operate safely on even the oldest old, if the elder is also frail, the stress of surgery can result in significant mortality, morbidity, and institutionalization. Frailty is a clinical syndrome marked by muscle atrophy, diminished strength, decreased physical activity, and exhaustion. It is independent of any specific disease, but it increases with age, and is a more powerful predictor of increased perioperative mortality, morbidity, length of stay, and cost than predictions based on age or comorbidity alone. As the Veteran and US populations grow older and more frail, it is critically important to identify effective strategies for improving the surgical outcomes of these patients.

"Prehabilitation" has the potential to improve surgical outcomes among the frail. Prior research demonstrates that inter-disciplinary rehabilitation strategies deployed after surgery enhance recovery and improve outcomes by building strength, improving nutrition, and optimizing home supports. Based on this success, there is growing interest in deploying similar interventions before surgery in what some call "prehabilitation." By modifying physiological and environmental risks, prehabilitation aims to augment patients' capacity to compensate for the stress of both surgery and recovery. Frail patients will likely benefit disproportionately from prehabilitation because they have the most diminished capacity to adapt to the stress of surgery. However, prehabilitation has not yet been studied in either Veteran or specifically frail populations.

Objectives: We will examine the feasibility of a novel, multifaceted pre-habilitation intervention aimed at improving postoperative outcomes for frail Veterans undergoing major abdominal surgery. Specific aims are to:

1. Estimate rates of recruitment, randomization, retention, and compliance with the prehabilitation intervention;
2. Measure (a) physical performance, (b) pulmonary function, and (c) nutrition at baseline and 2-week intervals to estimate changes over time and explore the optimal duration of prehabilitation (2 vs. 4 vs. 6 weeks); and
3. Estimate overall and treatment-specific summary statistics for postoperative outcomes in terms of 30- and 90-day (a) mortality, (b) major complications, (c) length of hospital stay, (d) health-related quality of life, (e) quality of surgical care, and (f) change in level of independent living.

Methods: This randomized pilot study will enroll a consecutive cohort of up to 50 Veterans identified as frail using a standardized frailty assessment and scheduled for major abdominal surgery on the general or urological surgery services at the VA Pittsburgh Healthcare System. We will randomize participants 1:1 to receive either: (1) standard preoperative optimization by the Interdisciplinary Medical Preoperative Assessment Consultation \& Treatment Clinic (IMPACT), or (2) prehabilitation + standard IMPACT optimization. The 6-week long prehabilitation intervention will include (1) strength and balance training; (2) inspiratory muscle training; and (3) nutritional coaching and supplementation. Assessments will include standard postoperative outcomes as well as the Short Physical Performance Battery to measure physical performance, Maximal Inspiratory Pressure to measure pulmonary function, and both prealbumin and the 7-point Subjective Global Assessment to measure nutrition. Outcomes will be assessed 30 or 90 days after surgery. Compliance with the prehabilitation regimen will be assessed through patient logs and pedometers. Analyses will inform the development of a larger randomized controlled trial testing the prehabilitation intervention. Findings will be relevant for the as many as 42,000 frail Veterans scheduled for major elective surgery each year.