Epidural Spinal Cord Stimulation for Respiratory Recovery in Cervical SCI

This is a multicenter, prospective, single-arm, exploratory investigator-initiated trial (IIT) conducted at Zhongda Hospital, Southeast University and the First Affiliated Hospital of Nanjing Medical University. The study aims to evaluate the safety and efficacy of epidural spinal cord electrical stimulation (ESCES) in patients with spinal cord injury (SCI) complicated by respiratory failure.

A total of 20 adult patients (aged 18-75 years) with C1-C5 level SCI for at least 2 weeks and respiratory failure requiring mechanical ventilation or presenting with hypoxemia/hypercapnia will be enrolled. Participants will receive standard conventional treatment plus ESCES. Electrodes will be surgically implanted at the C3-C5 epidural space, and stimulation will be delivered daily with individualized parameter titration based on patient tolerance.

The primary outcomes are Edi peak, change of Edi peak and frequency. Secondary outcomes include tidal volume, diaphragmatic ultrasound parameters, cough strength, 90-day ventilator-free days, ICU length of stay, and survival at 90 and 180 days.

The observation period is defined as the period from enrollment until 1 month after enrollment or until successful weaning from mechanical ventilation, ICU discharge, removal of the epidural stimulation electrode, withdrawal from the study, or death, whichever occurs first.

This study is the first systematic exploration of ESCES for respiratory function recovery in SCI patients with respiratory failure, and may provide a novel therapeutic strategy for this population. The trial is expected to run for approximately 30 months. Participation is voluntary, and participants may withdraw at any time without affecting their subsequent care.

Inclusion criteria

• Age between 18 and 75 years, with BMI <30 kg/m².
• Cervical SCI involving levels C1-C5 for at least 2 weeks.
• Respiratory failure defined by one or more of the following:

• Peripheral oxygen saturation <90% on room air;
• Arterial oxygen tension (PaO₂) <60 mmHg;
• Respiratory acidosis (PaCO₂ >45 mmHg with pH <7.35);
• Requirement for mechanical ventilation.
• Maximum inspiratory pressure (MIP) >-15 cmH₂O.
• Judged by the treating physician to be unable to tolerate continuous ventilator weaning for ≥48 hours due to SCI.
• Written informed consent provided by the participant or legally authorized representative.

Exclusion criteria

• Active infection at the planned electrode implantation site, severe systemic infection, or existing implanted neurostimulation devices.
• Respiratory failure primarily caused by severe pneumonia, pulmonary contusion, pneumothorax, hemothorax, chronic obstructive pulmonary disease, or requirement for home oxygen therapy within the previous 6 months.
• New York Heart Association (NYHA) class III or IV heart failure or implanted cardiac pacemaker.
• Severe hepatic or renal dysfunction (Child-Pugh class C liver disease or estimated glomerular filtration rate ≤30 mL/min/1.73 m²) or dialysis dependence.
• Generalized seizures, traumatic brain injury, intracranial hypertension, intracranial aneurysm with Glasgow Coma Scale score ≤12, or neuromuscular disorders affecting respiratory function.
• Expected survival <72 hours or refusal of life-sustaining treatment.
• Pregnancy or breastfeeding.
• Any other condition considered by the investigator to make study participation inappropriate.