Ultrasound-Guided Percutaneous Peripheral Nerve Stimulation: Neuromodulation of the Brachial Plexus or Suprascapular Nerve for Postoperative Analgesia following Shoulder Rotator Cuff Repair
Ilfeld BM, Gabriel RA, Nguyen PL, Jaeger PT, Robertson C, Hentzen ER, Covey DC, Meunier MJ
University California San Diego
•Percutaneous peripheral nerve stimulation (pPNS) or “neuromodulation” is an analgesic modality involving the insertion of an electrical lead through an introducing needle—obviating the requirement of a surgical incision for placement—followed by the introduction of electric current
•Neuromodulation is based on “gate control theory”, in which electric current stimulates large-diameter afferent nerve fibers that subsequently interrupt communication (the “gate”) from small-diameter pain fibers to the central nervous system at the level of the spinal cord.
•This therapy has multiple theoretical benefits over existing analgesic modalities: a lack of systemic side effects (e.g., opioid-induced nausea, respiratory depression), diversion and abuse potential, local anesthetic-induced sensory, motor, and proprioception deficits, and significant foreign body infection risk
•The US FDA has cleared an available lead and stimulator for the treatment of acute pain for use up to 60 days
•Percutaneous PNS has been used to treat chronic pain and post-operative pain following knee arthroplasty
•The purpose of this feasibility study was to explore the possibility of providing analgesia following painful ambulatory shoulder surgery with pPNS
•The protocol was prospectively registered (NCT02898103), approved by the local IRB, and all subjects provided written informed consent. Lead insertion occurred within 2 weeks prior to open unilateral rotator cuff repair.
•A helically-coiled, insulated electrical lead was percutaneously inserted to target either the suprascapular nerve immediately superficial to the scapula, or the brachial plexus using a posterior approach into the anterior aspect of the middle scalene muscle ; both using a short-axis, in-plane ultrasound-guided approach.
•For subjects with a suprascapular lead, an interscalene perineural catheter was inserted using a posterior, in-plane, ultrasound guided technique for use exclusively as a rescue analgesic (no initial local anesthetic bolus administered or infusion initiated).
•A general anesthetic was administered during surgery and a pulse generator (“stimulator”) was connected to the lead and initiated in the recovery room (SPRINT, SPR Therapeutics, Cleveland, Ohio).
•Rescue analgesia was provided with opioids and—if needed—a ropivacaine 0.2% perineural infusion via a popliteal catheter during the first three days. Subjects were discharged home and followed daily by telephone.
•Perineural catheters were removed by subjects at home within the first three postoperative days (POD); and, subjects returned to clinic for lead removal with simple traction by an investigator between POD 14-28.
•The subject with the brachial plexus lead (n=1) experienced no pain and required no opioids from POD 1-14 and 30 (Figures, Tables).
•In contrast, during insertion we could not induce comfortable sensations in subjects with a suprascapular lead (n=2) suggesting suboptimal placement, at best. These subjects used their rescue perineural infusion POD 0-3, yet reported more pain and opioid requirements relative to the subject with a brachial plexus lead.
•This proof-of-concept study demonstrates that pPNS is feasible for ambulatory shoulder surgery; and suggests that a brachial plexus lead inserted into the middle scalene muscle both provides analgesia and decreases reliance on opioids following arthroscopic rotator cuff repair.