Percutaneously implanted epidural stimulation attenuated drop in blood pressure during exoskeletal and task specific training. A case report

Research Objectives: To describe cardiovascular function in a chronic-complete spinal cord injury (SCI) enabled by percutaneous spinal cord epidural stimulation (SCES). Improvement in blood pressure is described in relation to exoskeletal-assisted walking (EAW) and changes in cardiovascular autonomic regulation.

Design: Case report as a part of a clinical trial.

Setting: SCI Research Lab at a Medical Center

Participants: 54-year-old male, 24 years post a T4 complete (AIS A) SCI.

Interventions: Two eight-electrode percutaneous leads were implanted at T10/T11 to mid T12 vertebrae to enable motor control below the level of injury. EAW was set at fixed assist mode by gradually lowering the assistance to allow the participant to actively step with SCES ON. Autonomic mapping was conducted using a standing frame in various positions. Beat-to-beat blood pressure was measured as SCES was incrementally activated.

Main Outcome Measures: The primary outcome was cardiovascular response at a 60-degree head-up-tilt test. Systolic blood pressure (SBP), heart rate (HR), absolute power of low-frequency (LF), and high-frequency (HF) components of a heart-rate variability analysis were collected in supine and tilt with and without the presence of SCES.

Results: Over 6 months, the participant reduced EAW assistance from 100 to 70%. Signs of orthostatic hypotension were observed during week 6 of training with SBP reduction from 113 to 55mmHG during EAW. Following autonomic mapping, SCES configuration increased seated SBP by 15.7% and DBP by 25.5% after 60 minutes of EAW. During task-specific training, SBP and DBP increased by 18% and 71%, respectively, with SCES ON.
Tilt table assessments, from supine to tilt decreased SBP (assessment one: 142.0 to 109 mmHg; assessment two: 133 to 100 mmHg) with SCES OFF (approximately 23-25%). At assessment two, SBP increased (average 143 mmHg) in a supine lying position. Following tilt, the decrease in SBP was attenuated from 143.3 to 116.4 mmHg with SCES ON at 16.9 mA (approximately 18%).

Conclusions: Standardized autonomic mapping individually enhanced cardiovascular response and mitigated signs of orthostatic hypotension in a person with complete SCI.

Author(s) Disclosures: Nothing to disclose.