Nonawake vs awake placement of spinal cord stimulators: A prospective, multicenter study comparing safety and efficacy

Abstract

BACKGROUND: Spinal cord stimulation (SCS) is a common intervention for managing intractable pain. Generally, leads are implanted in a minimally invasive procedure with verbal feedback regarding the location and nature of generated paresthesias by active stimulation; in this way their optimal location can be confirmed. However, lead placement under general anesthesia can have additional benefits. OBJECTIVE: To investigate the outcomes of awake vs asleep lead placement procedures. METHODS: In this prospective multicenter open label trial, subjects were assigned to undergo asleep (n = 19) or awake (n = 11) SCS implantations in a nonrandomized fashion. Subjects received paddle leads following laminotomy. The process for intraoperative programming differed between the groups: Awake subjects participated by verbally reporting on pain-paresthesia overlap, while for asleep subjects, paresthesia location was inferred based on electromyographic monitoring. RESULTS: Operative time was shorter for the asleep group compared to the awake group (88.9 ± 51.2 min vs 125.2 ± 37.9, respectively; P = .018), as well as 27% less total time spent in the operating room (95.4 ± 48.6 min vs 130.6 ± 39.9; P = .014). At 6 wk postimplant, subjects in the asleep group had better pain-paresthesia overlap than the awake group (83.5% ± 19.8 coverage vs 46.6% ± 44.5, respectively; P= .05) and fewer extraneous paresthesia (16.7% ± 23.1 vs 71.2% ± 30.3; P < .001). Both groups had equivalent levels of pain relief (more than 50%) after 6 and 24 wk of treatment. There were 2 adverse events in the asleep group compared to 6 in the awake group. CONCLUSION: Electrophysiological monitoring during asleep SCS implantation is a robust tool becoming more frequently used. This comparative prospective series demonstrates that asleep placement allows for shorter procedure and operating room times with superior paresthesia coverage profiles, while maintaining lower adverse events and equal clinical outcomes for pain relief.