Effects of Lower Thoracic Spinal Cord Stimulation on Bowel Management in Individuals With Spinal Cord Injury

Abstract

Objective: To systematically determine whether use of the spinal cord stimulation (SCS) system to restore cough may improve bowel management (BM) in individuals with spinal cord injury (SCI).

Design: Experimental studies (clinical trial).

Setting: Inpatient hospital setting for electrode insertion; outpatient setting for measurement of respiratory pressures; home setting for application of SCS.

Participants: Participants (N=5) with cervical SCI.

Intervention: A fully implantable SCS cough system was surgically placed in each subject. SCS was applied at home, 2-3 times/d, on a chronic basis, every time bowel regimen was performed and as needed for secretion management. Stimulus parameters were set at values resulting in near maximum airway pressure generation, which was used as an index of expiratory muscle strength. Participants also used SCS during their bowel routine.

Main outcome measures: Airway pressure generation achieved with SCS. Weekly completion of Bowel Routine Log including BM time, mechanical measures, and medications used.

Results: Mean pressure during spontaneous efforts was 30±8 cmH₂O. After a period of reconditioning, SCS resulted in pressure of 146±21 cmH₂O. The time required for BM routines was reduced from 118±34 minutes to 18±2 minutes (P<.05) and was directly related to the magnitude of pressure development during SCS. Mechanical methods for BM were completely eliminated in 4 patients. No patients experienced fecal incontinence as result of SCS. Each participant also reported marked overall improvement associated with BM.

Conclusions: Our results of this pilot study suggest that SCS to restore cough may be a useful method to improve BM and life quality for both patients with SCI and their caregivers. Our results indicate that the improvement in BM is secondary to restoration of intra-abdominal pressure development.

Trial registration: ClinicalTrials.gov NCT01659541.

Keywords: Bowel Management; Quadriplegia; Rehabilitation; Spinal cord injuries.