Spinal Stimulation + FES-Assisted Cough Training in SCI

The overall objective of this proposal is to determine if transcutaneous spinal cord stimulation (tSCS) delivered concurrently with functional electrical stimulation (FES)-assisted cough training (FES-Cough) can synergistically improve cough strength and coordination in individuals with acute/subacute SCI. Aim 1: Determine the efficacy of tSCS combined with FES-Cough in individuals with acute/subacute SCI to improve cough strength and respiratory function. Spirometric values and respiratory pressures will be assessed as well as breathlessness and hypophonia after 20 sessions of active tSCS combined with FES-Cough vs. sham tSCS combined with FES-Cough administered over 4-6 weeks Aim 2: Analyze the effect of tSCS combined with FES-cough on cough coordination and sequencing through a detailed analysis of cough partial expiratory flow-volume (CPEFV) curves and respiratory muscle EMG before and after each of the interventions, including comparative analysis of EMG cough activity between individuals with neurologic injury and healthy control participants.

Th hypothesis is that participants receiving tSCS + FES-Cough will demonstrate significantly greater improvements in unstimulated peak cough flow, normalized cough phase timing, and improved flow-volume characteristics compared to the sham + FES-Cough group.

Inclusion criteria

• Currently admitted for inpatient rehabilitation at Shirley Ryan AbilityLab
• History of traumatic spinal cord injury with Neurologic Level of Injury (NLI) C1-T1, and AIS A-C on admission exam
• Between 14-60 days from date of injury at time of enrollment
• Baseline PCF below 270 L/min
• Anatomical airway or tolerating occlusion of tracheostomy with either a one-way speaking valve or a cap for at least 60 minutes
• Medically cleared by the participants primary inpatient physiatry attending physician

Exclusion criteria

• Individuals with pre-morbid chronic pulmonary conditions, day-time ventilator dependence, uncontrolled autonomic dysreflexia, moderate to severe traumatic brain injury, developmental delay, diagnosis of active cancer, or secondary progressive neurologic disorder
• Individuals with contraindications to the interventions of interest:

• TSCS and Abdominal FES: pacemaker, compromised skin integrity under site of stimulation, implanted defibrillators, deep brain stimulator(s), uncontrolled epilepsy or seizures, pregnancy, recent myocardial infarct, diaphragmatic pacer
• TSCS: Severe osteoporosis
• Abdominal FES: unhealed rib fracture, sternal precautions, recent pneumothorax, spine bracing impacting ability to place stimulation pads.
• Individuals with medical instability impacting the safety and feasibility of participation including the inability to tolerate sitting upright >45 degrees for 15 minutes, acute unresolved medical complications as determined by study physician to be exclusionary, transferred to higher level of medical care for ≥5 consecutive days or >14 days total during trial period, and those with halo spine bracing
• Individuals who are currently enrolled in another interventional research study are excluded from participating to eliminate potential influence of additional experimental interventions on study outcomes and to maintain standardization of study protocol