The Effects of Stellate Ganglion Block Sleep in U.S. Active Duty Service Members and Veterans Receiving Prolonged Exposure Therapy for PTSD

The Effects of Stellate Ganglion Block on Sleep in U.S. Active Duty Service Members and Veterans Receiving Prolonged Exposure Therapy for Posttraumatic Stress Disorder (PTSD)

Participants in this study will have already been enrolled in another research study: Combining Stellate Ganglion Block with Prolonged Exposure for PTSD, NCT05889741. The investigators are using a Sleep Profiler, EEG headband to monitor a participants brainwaves while they sleep to see what effects the Stellate Ganglion Block injection has on their sleep. Participants will wear the headband for 3 nights before the injection and then 3 nights after the injection. Participants will also complete self-report questionnaires regarding their sleep prior to the injection and following the injection. Approximately 40 participants will be included in this study. This study is a nested observational study whereby participants in the parent study who elect to participate will have their sleep assessed using the EEG headband device and self-reported sleep measures performed.

Objectives: The primary objective of this project is to observe the impact of stellate ganglion block (SGB) on objective measures of sleep (using a wearable headband) and subjective measures of sleep (self-report measures) in active duty service members and veterans receiving prolonged exposure therapy (PE) for PTSD. The secondary objective is to evaluate sleep improvements as a mechanism for PTSD treatment outcomes in this population.

Specific Aim 1: To compare the effects of a SGB with ropivacaine (active) versus a SGB with saline (sham) on objective measures of sleep macroarchitecture (i.e., rapid eye movement [REM] sleep and slow wave sleep) and sleep continuity (i.e., sleep onset latency, wake after sleep onset, number of awakenings, total sleep time, and sleep efficiency).

Specific Aim 2: To compare the effects of SGB (active)+PE versus SGB (sham)+PE on sleep microarchitectural indicators of heightened central nervous system arousal (i. e., high-frequency and low-frequency power spectral density, frequency of occipital alpha-indexed micro-arousals, slow wave features [e.g., slope, density] during N3 sleep, proportion of phasic and tonic REM sleep and REM density during REM sleep).

Specific Aim 3: Specific Aim 3: To evaluate the effects of SGB (active)+PE versus SGB (sham)+PE on self-reported measures of insomnia and nightmares.

Inclusion Criteria:

1. Ability to provide informed consent and follow study-related instructions.
2. Be randomized into the study titled "Combining Stellate Ganglion Block with Prolonged Exposure for PTSD: A Randomized Clinical Trial." NCT05889741
3. Indicates willingness to wear the Sleep Profiler sleep monitor and to complete self-report assessments.

Exclusion Criteria:

1. Pre-existing skin or soft tissue condition that precludes the ability to wear the Sleep Profiler headband.