The Pecs II targets the interfacial plane between the pectoralis major muscle and the pectoralis minor muscle as does the Pecs I but also targets the interfacial plane between the pectoralis minor muscle and the serratus anterior muscle, aiming to block intercostal nerves 3 to 6, intercostobrachial and the long thoracic nerves, all of which are necessary for axillary node dissection.¹

A recent meta-analysis included 14 different randomized trials looking at Pecs II block versus paravertebral blocks. They found that Pectoralis-II reduces pain intensity and morphine consumption during the first 24 h postoperatively when compared with systemic analgesia alone; and it also offers analgesic benefits non inferior to those of paravertebral block after breast cancer surgery.²

Serratus Anterior Plane Block and Pecs II fascial plane blocks are equally efficacious in post-thoracotomy pain management compared with intercostal nerve block, but they have the additional benefit of being longer lasting and are as easily performed as the traditional intercostal nerve block.³

In open heart surgery, parasternal block provided longer block duration with lower postoperative pain and sedation scores than the PECS II block, with lower cumulative morphine consumption.⁴

Dexamethasone 8 mg when added to ropivacaine 0.2% for PECS II block in unilateral radical mastectomy was not found to reduce total opioid consumption over 72 postoperative hours or to prolong duration of analgesia as compared to pure ropivacaine 0.2%.⁵

Neshith Govil et al demonstrated that instillation of lignocaine to block the pectoral nerves allows better postoperative analgesia compared to other patients without regional anaesthesia and decreases the secretion of angiogenesis markers, which contributes to tumor generalization.⁶

References

1. Blanco R, Fajardo M, Parras Maldonado T. Ultrasound description of Pecs II (modified Pecs I): a novel approach to breast surgery. Rev Esp Anestesiol Reanim 2012 Nov;59(9):470–5.

2. Hussain N, Brull R, McCartney CJL, Wong P, Kumar N, Essandoh M, Sawyer T, Sullivan T, Abdallah FW. Pectoralis-II myofascial block and analgesia in breast cancer surgery: a systematic review and meta-analysis. Anesthesiology 2019 Sep;131(3):630–648.

3. Kaushal B, Chauhan S, Saini K, Bhoi D, Bisoi AK, Sangdup T, Khan MA. Comparison of the efficacy of ultrasound-guided serratus anterior plane block, pectoral nerves II block, and ıntercostal nerve block for the management of postoperative thoracotomy pain after pediatric cardiac surgery. J Cardiothorac Vasc Anesth 2019 Feb;33(2):418–425.

4. Turkmen S, Mutlu M. Evaluation of the effect of different block techniques on open-heart surgery in the postoperative period: a prospective observational study. Cardiovasc J Afr 2022 Mar 25;33:1–4.

5. Hoerner E, Gasteiger L, Ortler M, Pustilnik V, Mathis S, Brunner C, Neururer S, Schlager A, Egle D, Putz G. The impact of dexamethasone as a perineural additive to ropivacaine for PECS II blockade in patients undergoing unilateral radical mastectomy - A prospective, randomized, controlled and double-blinded trial. J Clin Anesth 2022 May;77:110622.

6. Govil N, Naithani M, Ravi B, Sharda P, Tripathi M, Bhardwaj BB. A randomized single-blinded, parallel-arm group feasibility trial evaluating role of pectoral nerve block on serum vascular endothelial growth factor levels in patients undergoing unilateral modified radical mastectomy. Med Gas Res 2020 Oct-Dec;10(4):179–184.