Serratus anterior plane blocks provide opioid-sparing analgesia in patients with isolated posterior rib fractures: a case series

  • Peter RoseEmail author
  • Reva Ramlogan
  • Timothy Sullivan
  • Anne Lui

To the Editor,

Serratus anterior plane (SAP) blocks provide effective analgesia in patients with antero-lateral rib fractures but are reportedly ineffective for posterior rib fractures.1,2 Serratus anterior plane injections consistently result in local anesthetic spread to lateral cutaneous branches of intercostal nerves that innervate the superficial antero-lateral chest wall, but were thought to spare the intercostal nerves that supply the posterior rib periosteum and intercostal muscles.3,4 Nevertheless, a recent cadaver study showed that, in the traumatized hemithorax, SAP injectate consistently reaches multiple intercostal nerves and spreads more posteriorly, reaching the medial border of the scapula.5 This study helps elucidate the mechanism of SAP block analgesia in rib fractures and provides an anatomical explanation for analgesia of posterior rib fractures.

At our institution, we have developed a protocol for early thoracic epidural or paravertebral analgesia to prevent...


Conflict of interest

None declared.

Editorial responsibility

This submission was handled by Dr. Hilary P. Grocott, Editor-in-Chief, Canadian Journal of Anesthesia.




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Copyright information

© Canadian Anesthesiologists' Society 2019

Authors and Affiliations

  1. 1.Department of AnesthesiologyThe Ottawa HospitalOttawaCanada
  2. 2.Department of AnesthesiaUniversity of OttawaOttawaCanada

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