Pulmonary Function and Sleep-Related Disorders During Cervical Administration of Intrathecal Baclofen in Adults With Spinal Cord Injury (Cervit-B): Protocol for a Multiphase Single-Arm Intervention Trial.

Background: The effect and safety of intrathecal baclofen (ITB) on generalized spasticity of the lower extremity have been well described in numerous studies, whereas the safety and effect on spasticity of the upper extremity during cervical administration seems to be less certain.

Objective: We aim to establish the safety of cervical administration of ITB on pulmonary function and sleep-related disorders in adults with a cervical spinal cord injury with functional hindering spasticity. In addition, we aim to explore the effect of cervical ITB on the reduction of spasticity; participant satisfaction; and improvement at the level of function, activities, and participation.

Methods: The study is a multiphase single-arm intervention study. Before the start of the study, participants are screened for the presence of sleep-related disorders, and pulmonary function is assessed using spirometry and a capillary blood gas sample. Participants are allowed to start the first phase of the study if there are no signs of sleep-related disorders or if these are adequately treated. The PCO (partial pressure of CO in capillary blood sample) should be between 4.5 and 6.5 kPa. In the first phase of the study, an extracorporeal pump will be used to investigate whether cervical administration of ITB leads to a reduction of spasticity without an adverse effect on pulmonary function and sleep-related disorders. In case of a safe (no adverse effects) and positive (reduction of spasticity) result of the trial, a baclofen pump will be implanted in the second phase of the study. After implantation, the dosage of ITB will be slowly increased, and eventually, the use of oral spasmolytics will be phased out. The dosage will be increased during the monitoring of pulmonary function and sleep-related disorders. In the second phase of the study, a pulse oximetry will be performed, and pulmonary function; spasticity; satisfaction; and the level of function, activities, and participation will be assessed at 3, 6, and 12 months after definitive implantation of the baclofen pump.

Results: The first participant was recruited on May 23, 2023. Data collection and analyses are expected to be completed in 2027.

Conclusions: Currently, little is known about the safety and effectiveness of cervical administration of ITB for the treatment of upper extremity spasticity. We aim to establish the safety and explore the efficacy of this procedure. This paper describes the protocol of this study.

International Registered Report Identifier (irrid): DERR1-10.2196/70362.