Orthostatic Tolerance During FES (Functional Electrical Stimulation)-Walking in Paraplegia
Condition: Spinal Cord Injury
MeSH terms: Spinal Cord Injuries; Paraplegia
Study type: Interventional
Phase: Phase 1

Summary: 
      Objective:

      The objective of this research is to undertake a safety and viability study of FES-evoked
      stepping in individuals with paraplegia. The rationale for this objective is based upon the
      need to clarify whether physiological limitations, especially orthostatic intolerance, limit
      functional mobility outcomes. The cardiovascular, autonomic, and muscle metabolic factors
      governing orthostatic tolerance during skin-surface FES stepping will be investigated, since
      this functional task forms the basis of upright mobility and engenders strong physiological
      challenges upon key regulatory processes in the SCI (spinal cord injury) patient.

      Specific Hypotheses:

      i. Reduction of blood pressure will be greater during FES-evoked stepping than during passive
      stepping; ii. Reduction of blood pressure will be greater during FES-evoked stepping with no
      upper body component versus FES-stepping with an upper body component; iii. Blood pressure
      will be reduced even further during FES-evoked stepping following a 6-week
      progressive-intensity gait training intervention.
    

Detailed description: 
      Aims:

      The primary aim of the safety and viability study is to assess changes in blood pressure
      during up to 60-min of FES-evoked stepping versus up to 60-min of stepping.

      A secondary aim is to investigate changes in blood pressure during FES-assisted stepping with
      and without a voluntary upper-limb component of gait.

      Specific Hypotheses:

      i. Reduction of blood pressure will be greater during FES-evoked stepping than during passive
      stepping; ii. Reduction of blood pressure will be greater during FES-evoked stepping with no
      upper body component versus FES-stepping with an upper body component; iii. Blood pressure
      will be reduced even further during FES-evoked stepping following a 6-week
      progressive-intensity gait training intervention.

      Primary Outcome: The primary outcome measure for this study is the change of systolic blood
      pressure during three FES-evoked stepping conditions, as described below. Each condition is
      defined as up to 60-min of continuous gait.

      Secondary Outcomes: Secondary outcomes include a change of diastolic blood pressure and the
      duration of orthostatic tolerance. Orthostatic tolerance will be assessed as the time that
      the subject can perform stepping before the onset of orthostatic hypotension. The duration of
      orthostatic tolerance will be determined by the time at which one of the following occur: (i)
      60 continuous minutes of stepping; or (ii) orthostatic hypotension, defined as a reduction in
      systolic blood pressure of > 20 mmHg or diastolic blood pressure of >10 mmHg; or (iii) signs
      and symptoms of pre-syncope; or (iii) upon subject request. Throughout each trial, heart rate
      and blood pressure will be monitored continuously. In addition to the primary and secondary
      outcome variables, several additional measurements that may contribute to orthostatic
      tolerance, or indeed, intolerance, will be assessed at 10-min intervals during stepping.
    

Intervention name(s): FES-evoked functional upright gait
Intervention type(s): Procedure
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Functional Electrical Stimulation; Gait; Blood pressure; Orthostatic Hypotension; Cardiovascular responses; Near-infra red spectroscopy