UGRAbas

4 – References

Blanco R, Parras T, McDonnell JG, Prats-Galino A: Serratus plane block: a novel ultrasound-guided thoracic wall nerve block,
Anaesthesia 68: 1107-1113 (2013)

2 – Anatomy

With the superficial serratus plane block, the needle tip is inserted into the fascial space between the serratus anterior muscle and the latissimus dorsi muscle caudad to the teres major muscle

Local anaesthetic injected into this fascial plane covers the thoracic intercostal nerves and their lateral cutaneous branches – and also the thoracodorsal nerve which innervates the latissimus dorsi muscle and the long thoracic nerve which innervates the serratus anterior muscle. The last mentioned nerves run alongside the thoracodorsal artery.

Blanco R, Parras T, McDonnell JG, Prats-Galino A (see ref.) have also described a serratus plane block with injection of local anaesthetic into the fascial plane deep to the serratus anterior muscle

This deeper serratus plane block also produces analgesia of the thoracic intercostal nerves and the lateral hemithorax; however, the analgesia of the deep block seems to last a shorter time than the superficial serratus plane block

3 – Sonoanatomy and needle insertion

Place the patient supine

Place the probe in the parasagittal plane on the midclavicular line and the fifth rib is identified by counting from above. The rib is tracked to the midaxillary line. Rotate the probe 45 degrees from the axial plane.

The latissimus dorsi, the serratus anterior and the teres major muscles are overlying the fifth rib (see previous page). The thoracodorsal artery can be used as a marker of the fascial plane between the latissimus dorsi and serratus anterior muscles.

The needle is inserted from the anterior end of the probe and advanced in-plane

Inject 25 mL ropivacain 0.2% into the fascial plane between the serratus anterior and latissimus dorsi muscles

11 – Sonoanatomy: Step two of the PECS II block

At the infero-lateral margin of the minor pectoral muscle the strong Gerdy’s ligament (= the lower part of the clavicopectoral fascia) connects the minor pectoral muscle to the axillary fascia

When the needle tip penetrates Gerdy’s ligament it enters the the lower part of the axillary space between the Gerdy’s ligament antero-laterally and the serratus anterior muscle covering the lateral thoracic wall medially in the axilla

15 – References

Blanco R: The

12 – Sonoanatomy: Identify the ribs

Below the lateral third of the clavicle the axillary artery is typically located on top of the second rib

Ribs III and IV can be identified by sliding caudad and counting

13 – Sonoanatomy: Needle insertion for step two of PECS II

The needle is inserted in-plane from the cranial end of the probe until the tip of the needle penetrates the infero-lateral margin of the minor pectoral muscle and enters the lower part of the axilla between the Gerdy’s ligament and the serratus anterior muscle

1 – Indications

The serratus plane block produces analgesia of the lateral thoracic wall including the axilla.

The indications of the serratus plane block are postoperative analgesia after surgery of:

– lateral thoracic wall

– breast

– axilla

5 – Anatomy: The clavipectoral fascia penetrated by nerve and vessels

The part of the clavipectoral fascia close to the clavicle – the costocoracoid ligament – is penetrated by the cephalic vein, the lateral pectoral nerve and the thoracoacromial artery

8 – Anatomy: Cutaneous innervation of the branches of the intercostal nerves

The lateral cutaneous branches (syn: lateral mammary branches) of the intercostal nerves innervate the skin of the axilla (the intercostobrachial nerve, which is the lateral cutaneous branch from intercostal nerve T2 innervates part of the skin of the axilla and continues to innervate the skin of the proximal medial surface of the arm) and the lateral part of the breast

The anterior cutaneous branches (syn: medial cutaneous branches or medial mammary branches) of the intercostal nerves innervate the supero-medial part of the breast