In this video, we discuss the innervation of the shoulder and outline two approaches to providing high-quality analgesia for shoulder surgery while minimizing the risk for phrenic nerve blockade
Small point with the beginning narration: After having done a few cadaver contrast injections myself, I'd like to dispute the notion that phrenic blockade with the interscalene block occurs because anesthetic gets around the anterior scalene muscle into the jugular sheath. I have never, not once, observed any spread of injectate on either ultrasound or x-ray, into that area. And also note that we never see any effect of vagal blockade on either side, despite a near-universal effect on the phrenic nerve. It seems to me that phrenic blockade occurs because of proximal, not medial, spread of anesthetic along the brachial plexus sheath to the phrenic origins at the cervical roots. This is what I observed in contrast injections, and it also helps explain why our brachial plexus blocks involve the phrenic progressively less often, as we move distally.
@Olivia Olivia. Safe in terms of avoiding phrenic nerve blockade (assuming your approach to the Suprascapular nerve block is the posterior approach in the spinoglenoid notch). If you are concerned about local anesthetic systemic toxicity you can limit your drug volume or concentration. We created a free app to help calculate maximum local anesthetic doses. It can help guide how much local anesthetic the surgeon can use to safely supplement your block. apps.apple.com/us/app/safelocal/id1440999841 or find it in the google play store.
I realize your video focused on the suprascapular and axillary nerve combination. But from your video, i am wondering if you could do a suprascapular n block from the spinoglenoid notch combined with an infraclavicular block (to block the plexus at the level of the cords) and get adequate postoperative analgesia for shoulder arthroscopy? Have you actually used this combination...or is there any literature that has looked at this approach?
A case report of the combination: Panchamia JK, Olsen DA, Amundson AW. Unique Phrenic Nerve-Sparing Regional Anesthetic Technique for Pain Management after Shoulder Surgery. Case Rep Anesthesiol. 2017;2017:1294913. doi:10.1155/2017/1294913
