Acute noninvasive ventilation (NIV) can successfully improve ventilatory efficiency during functional electrical stimulation (FES) exercise in spinal cord injury but may not improve peak oxygen consumption (VO2 peak) in all patients, according to study results published in CHEST.
Injury to the upper thoracic or cervical spinal cord can result in substantial ventilatory limitation resulting in a reduction in exercise capacity and exercise-based rehabilitation, increasing morbidity and mortality risk, and thereby not being able to achieve exercise intensities required to reduce all-cause cardiometabolic risk. Whole-body hybrid FES-rowing is a form of exercise that markedly increases active muscle mass via electrically-induced leg contractions.
Researchers tested the effect of NIV on ventilatory and aerobic capacities in 19 patients with spinal cord injury (ClinicalTrials.gov Identifier: NCT02865343). They found that NIV increased the exercise tidal volume (P <.05) and reduced breathing frequency (P <.05) compared with sham, leading to no change in alveolar ventilation but a trend toward increased oxygen uptake efficiency (P =.06). In patients who reached VO2 peak criteria, NIV failed to significantly increase VO2 peak; however, the range of responses revealed a correlation between changes in peak alveolar ventilation and VO2 peak (P <.05). In addition, patients with higher level injuries and shorter time since injury demonstrated the greatest increase in VO2 peak.
“Our results broadly illustrate the intimate role of pulmonary function in determining the capacity to perform whole-body hybrid FES-rowing exercise in patients with high-level spinal cord injury. In those for whom NIV induced an increase [alveolar ventilation], VO2 peak was increased,” summarized the investigators. “However, this effect was limited to patients with cervical [spinal cord injury] within a shorter time since injury, and it was more obvious in those with incomplete injury.”
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 [published online November 15, 2019]. CHEST. doi:10.1016/j.chest.2019.10.044