Study Effects of Intermittent Hypoxia on Restoring Hand Function Following SCI
Condition: Spinal Cord Injury
MeSH terms: Spinal Cord Injuries; Hypoxia
Study type: Interventional
Phase: Phase 1

Summary: 
      The goal of the study is to examine the effects of repeated breathing episodes of mild
      intermittent hypoxia (reduced oxygen) training on hand strength and grasping ability
      following cervical spinal injury, and to determine whether these changes result in improved
      hand function. If so, such changes may indicate hypoxia-induced spinal plasticity (ability of
      the nervous system to strengthen neural pathways based on new experiences), which could
      result in improvements in hand use for persons with spinal cord injury (SCI).
    

Detailed description: 
      The goal of the study is to examine the effects of repeated breathing episodes of mild
      intermittent hypoxia (reduced oxygen) training on hand strength and grasping ability
      following cervical spinal injury, and to determine whether these changes result in improved
      hand function. If so, such changes may indicate hypoxia-induced spinal plasticity (ability of
      the nervous system to strengthen neural pathways based on new experiences), which could
      result in improvements in hand use for persons with spinal cord injury (SCI).

      This idea stems from animal studies on respiration, in which investigators have shown that
      intermittent hypoxia induces spinal plasticity, strengthening neural connections within the
      spinal cord by a mechanism known as respiratory long-term facilitation. Exposure to mild
      hypoxia triggers oxygen sensors in the nervous system resulting in a cascade of events,
      including increased production of key proteins and, increased sensitivity of spinal cord
      circuitry necessary for improved respiration.

      Because previous work using animal models has shown that similar events occur along
      non-respiratory pathways, the investigators propose to investigate whether a comparable
      dosing scheme of daily, mild intermittent hypoxia can positively affect upper limb function
      in persons with cervical SCI.

      First, the investigators hypothesize that daily exposure of intermittent hypoxia training (7
      consecutive days) will result in a sustained improvement in rat forelimb function that is
      dose-dependent. To test this hypothesis, the investigators will quantify the effects of
      variations in the number of intermittent hypoxia episodes on forelimb function in cervical
      spinal injured rats.

      Second, the investigators hypothesize that daily exposure of intermittent hypoxia training
      will improve hand function in persons with cervical spinal injury. To test this hypothesis,
      the investigators will quantify the effect of mild intermittent hypoxia exposure, using a
      protocol derived from the animal model, on volitional grip strength and grasp function in
      persons with cervical SCI.

      The effects of mild intermittent hypoxia, known to increase spinal motor activity, will be
      assessed as a possible therapeutic intervention to promote functionally useful hand recovery.
      Results from this study will be valuable for identifying novel strategies to control spinal
      neuron excitability and for improving motor function in persons with spinal cord injury.
    

Intervention name(s): Acute Intermittent Hypoxia (AIH); SHAM-Intermittent Room Air
Intervention type(s): Drug; Other
Intervention description(s): Participants will breath intermittent low oxygen via air generators. The generators will fill reservoir bags attached to a non-rebreathing face mask. Oxygen concentration will be continuously monitored to ensure delivery of FIO2=0.09±0.02 (hypoxia) air for 15 minutes.Participants will receive treatment for up to seven visits.; This is a sham intervention to the AIH intervention. Participants will breath intermittent room air via air generators. The generators will fill reservoir bags attached to a non-rebreathing face mask. Oxygen concentration will be continuously monitored to ensure delivery of FIO2=0.21±0.02 (normoxia). Participants will receive treatment for up to seven visits.
Other intervention name(s): Hypoxia air mixture; Room air mixture
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: spinal cord injury, low oxygen, strength, motor control