In the serratus plane block, local anaesthetic is injected in fascial plane between the latissimus dorsi and serratus anterior muscle at the level of 5 th rib.
Nerves blocked: Lateral divisions of thoracic intercostal nerves (T2-T9) , long thoracic and thoracodorsal nerve.
- Breast surgeries- mainly wide local excisions
- Axillary clearance/sentinel node biopsy.
- Breast reconstruction surgery (Lattisimus dorsi flap)
- AV fistula surgery
- Rib fractures.
- Esophagectomy and anastomosis.
- Thoracoscopy/ Thoracotomy.
- Shoulder surgery (involving armpit).
POSITION:Patient in supine position or in lateral position and with the arm raised above the head. A high frequency linear transducer is placed at the level of nipple in an antero-posterior direction in the mid-axillary line. The serratus anterior muscle is identified lying close to the ribs and slide the transducer posteriorly until the longitudinal fibers of the lattisimus dorsi muscle is identified. Local anaesthetic in injected in the plane between lattisimus dorsi and serratus anterior muscle so that it spreads upto the level of axilla. Thoracodorsal artery will be visualized in this plane.
Dose : 20 mls 0.25% Bupivacaine or 0.4mls/kg of 0.25% Bupivacaine
Needle: 50mm B bevel needle (sufficient in vast majority of cases)
Needling technique: Inplane anterior to posterior (supine position) or posterior to anterior )lateral position)
Endpoint: Separation of fascial layer between lattisimus dorsi and serratus anterior
Surrogate structures: Thoracodorsal vessels, ribs, pleura
Tips: Interfascial spread is seen as the local anaesthetic splitting the layers and spreading beyond the needle tip.