Ventilatory Support to Improve Exercise Training in High Level Spinal Cord Injury (NIV-Ex)

The investigators have an existing exercise program (N>70) with a unique population of individuals with spinal cord injury (SCI) who have been enrolled in FES-RT for at least 6 months. Roughly half have high level SCI. Thirty individuals with high level SCI who have FES-row trained for at least 6 months will be randomized to (continued) FES-RT for 3 months with either NIV or sham NIV. Before and after training, the investigators will assess maximal aerobic capacity, ventilation, cardiac output, and arterio-venous oxygen difference. Based on the investigators current data, it is hypothesized that only those randomized to NIV will experience further increases in aerobic capacity and that these increases will relate to increases in cardiac output and arterio-venous oxygen difference. This Exploratory/Developmental Research project will lay the groundwork for a larger study of the impact of FES-RT+NIV to improve health and function in those with high level SCI.

Regular aerobic exercise with sufficient intensity can improve overall health, however daily energy expenditure is low in those with SCI, especially in those with high level lesions. We have developed Functional Electrical Stimulation Row Training (FESRT) that couples volitional arm and electrically controlled leg exercise, increasing the active muscle and resulting in benefits of large muscle mass exercise. Despite the potential for enhancing aerobic capacity, those with high level lesions (C4 to T2) have a remaining obstacle to attaining higher work capacities they have the greatest pulmonary muscle denervation and our preliminary work suggests this limits the aerobic capacity that can be achieved with FESRT. External ventilatory support could improve the ability to exercise train and hence enhance the adaptations to chronic exercise in high level SCI. Non invasive ventilation (NIV) during exercise training has been shown to improve gains in exercise capacity in those with similarly restrictive breathing. Therefore, the investigators hypothesize that the use of NIV during FESRT will reduce ventilatory limits to exercise, leading to increased aerobic capacity in high level SCI. Our aims are to determine the magnitude of improvement in aerobic capacity and its relationship to increases in maximal cardiac output and arterio venous oxygen difference after 3 months of FESRT+NIV compared to FESRT+shamNIV. The investigators have access to a large (N>70) and unique population of individuals with SCI who have been enrolled in FESRT for at least 6 months. Roughly half have SCI between C4 and T2. 30 individuals with high level SCI who have FES row trained for at least 6 months will be randomized to (continued) FESRT for 3 months with either NIV or sham NIV. Before and after training, the investigators will assess maximal aerobic capacity, ventilation, cardiac output, and arterio venous oxygen difference. Based on our current data, it is hypothesized that only those randomized to NIV will experience further increases in aerobic capacity and that these increases will relate to increased cardiac output and arterio venous oxygen difference. This Exploratory/Developmental Research project will determine feasibility and effectiveness of this approach to exercise and will lay the groundwork for a larger, controlled trial.

Investigators and technicians helping for performing the test and encouraging the patient will be blind. Only one investigator will monitor the ventilation during the test and won't be blind but won't be participating to any encouragement or data acquisition.

Subjects randomized to NIV will perform 12-weeks of FES-row training while receiving bi-level positive airway pressure ventilation applied through a full face-mask.

Subjects randomized to Sham-NIV will perform 12-weeks of FES-row training while receiving sham ventilation applied through a full face-mask.

The ventilator will be set in spontaneous mode with a ramp to reach a minimal pressure of 12 centimeters of water (cmH2O) during inspiration and 3 cmH2O during expiration.

The ventilator will be set in spontaneous mode with a ramp to reach a maximal pressure of 5 centimeters of water (cmH2O) during inspiration and 3 cmH2O during expiration.

Volunteers will perform a maximal incremental FES-row tests. Both NIV Support and Sham-NIV groups will perform tests in the Sham-NIV condition

Volunteers will perform a maximal incremental FES-row tests. Both NIV Support and Sham-NIV groups will perform tests in the Sham-NIV condition

Volunteers will perform a maximal incremental FES-row tests. Both NIV Support and Sham-NIV groups will perform tests in the Sham-NIV condition

Inclusion Criteria: Subjects aged 18 to 60 Have had high level SCI (neurological level ≥T3 with American Spinal Injury Association grade A or B or C) Medically stable Have FES-row trained for >6 months Exclusion Criteria: Hypertension(Blood pressure>140/90 mmHg) Significant arrhythmias Coronary disease Chronic respiratory disease Diabetes Renal disease Cancer Epilepsy Current use of cardioactive medications Current grade 2 or greater pressure ulcers at relevant contact sites Other neurological disease Peripheral nerve compression or rotator cuff tears that limit the ability to row History of bleeding disorder

Vivodtzev I, Picard G, Cepeda FX, Taylor JA. Acute Ventilatory Support During Whole-Body Hybrid Rowing in Patients With High-Level Spinal Cord Injury: A Randomized Controlled Crossover Trial. Chest. 2020 May;157(5):1230-1240. doi: 10.1016/j.chest.2019.10.044. Epub 2019 Nov 16.