Effect of a Novel Intervention Using Daily Intermittent Hypoxia and High Intensity Training on Upper Limb Function in Individuals With Spinal Cord Injury

Overview

Currently, there are a variety of approaches utilized in attempts to improve upper extremity function, including: traditional therapy, neuroprostheses, botulinum toxin injections, or surgical interventions. In addition, regenerative and restorative therapies, such as: epidural stimulation, functional electrical stimulation, and stem cell therapies, show promise in animal models, but are not ready for clinical translation. Subsequently, there is a clear need to develop new strategies that can stimulate spinal plasticity and strengthen existing synaptic connections in order to maximize the benefits of training paradigms. This study proposes the examine the effects of Acute Intermittent Hypoxia (AIH) in combination with upper extremity training, over the course of a month, to evaluate changes in upper extremity function, dexterity, and ability to complete activities of daily living. The use of acute intermittent hypoxia (AIH) has been demonstrated, through human and animal studies, to be an effective way of increasing spinal motor excitability and strengthening residual synaptic connectivity. AIH utilizes short duration (\<2 min) exposures to reduced oxygen levels (\~10% inspired oxygen), with alternating exposures to air with normal oxygen levels (\~21% inspired oxygen). Previous publications demonstrate that AIH is a safe and effective intervention to modify motor function in individual with chronic incomplete spinal cord injuries. The use of AIH has been shown to influence the activation in musculature, within 60-120 minutes of administration. In addition, when coupling AIH with overground gait training, an increase in functional endurance, as evaluated through the 6 minute walk test, and gait speed, as evaluated through the 10 meter walk test, were demonstrated. In addition, the use of hypoxic training has been studied in healthy individuals and athletes; however, literature examining the effect of a single bout of AIH on performance is limited.

This study proposes the examine the effects of Acute Intermittent Hypoxia (AIH) in combination with upper extremity training, over the course of a month, to evaluate changes in upper extremity function, dexterity, and ability to complete activities of daily living. The use of acute intermittent hypoxia (AIH) has been demonstrated, through human and animal studies, to be an effective way of increasing spinal motor excitability and strengthening residual synaptic connectivity. AIH utilizes short duration (\<2 min) exposures to reduced oxygen levels (\~10% inspired oxygen), with alternating exposures to air with normal oxygen levels (\~21% inspired oxygen). Previous publications demonstrate that AIH is a safe and effective intervention to modify motor function in individual with chronic incomplete spinal cord injuries. The use of AIH has been shown to influence the activation in musculature, within 60-120 minutes of administration. In addition, when coupling AIH with overground gait training, an increase in functional endurance, as evaluated through the 6 minute walk test, and gait speed, as evaluated through the 10 meter walk test, were demonstrated. In addition, the use of hypoxic training has been studied in healthy individuals and athletes; however, literature examining the effect of a single bout of AIH on performance is limited.