CLINICAL EXERCISE PHYSIOLOGISTS IN THE INPATIENT SETTING – A CASE STUDY
Authors: Leuck Lauren R. , Reynolds Toni M. , Arrom Andrea , Paul Ashlynne R. , Fitzgerald Regan N. , Lessert Natalee F. , Koch Marissa I. , Roma Erik A. 
Published: February 2025

https://youtu.be/i0pv5V6NKxM

INTRODUCTION
Preservation of functional capacity for patients admitted to the cardiovascular intensive care unit (CVICU) relies heavily on interventions prescribed by physical therapy. Traditional interventions are bed/chair exercises utilizing only body weight and ambulation around the unit. In this case, the clinical exercise physiologist (CEP) sought to push this standard of care to prepare a subject implanted with a BiVACOR total artificial heart (TAH) for orthotopic heart transplantation (OHT). This serves to present the methods in doing so and the need to further implement the role of clinical exercise physiologists in the inpatient setting.

CASE PRESENTATION
A 51-year-old male with history of chronic nonischemic cardiomyopathy, hypertension, diabetes mellitus, hyperlipidemia, and obesity presented to the hospital for right heart catheterization (RHC) in the setting of increased heart failure symptoms. Results of RHC led to admission and listing as UNOS status 4 for OHT. Hospital course was complicated by hypotension, ventricular tachycardia, and chronic kidney disease. Cardiothoracic surgery determined the need for mechanical circulatory support, a TAH as bridge to transplant. The patient elected to undergo implantation of BiVACOR, a TAH geared towards individuals with biventricular or univentricular heart failure where left ventricular assist device is not recommended. The patient is part of the BiVACOR Early Feasibility Trial in humans, approved by the FDA – he was the third human implant and would remain in hospital until OHT. The goal of the multi-disciplinary team was to preserve functional capacity during admission.

MANAGEMENT
Before implant, the patient’s 6-minute walk test (6MWT) distance was 320 meters, 2.52 METs. Post-implant in the ICU, the patient walked 1,800 feet 4 times per day. His 6MWT distance 13 days post-implant was 411 meters, 2.95 METs. By day 22 post-implant the patient progressed to recumbent bike cycling intervals. He was able to tolerate one 3-minutes interval and two 4-minutes intervals, split by 6-minutes rest intervals. His prescription was to cycle at 55-65 RPMs for 10-15 minutes three days per week with progression to 30 minutes continuously, 5-6 days per week. The patient was transplanted prior to completing any further sessions. During the cycling session, his blood lactate was measured at 5.2 mmol and hemoglobin 5.7 g/dL. His blood pressures remained stable, with normal responses to exercise, and pump flow increased from 8.9 L/min at rest to 12.5 L/min at peak exercise. Reported quadriceps muscle fatigue was the reason for session discontinuation.

DISCUSSION
Inpatient rehab goals of care should evolve to include various modalities of exercise that allow for more physiological adaptations, decreasing the impact of frailty and improving quality of life during admission. This patient’s case is an attestation to the growing need for exercise intervention prescribed by the CEP at all levels of care.