The pecs anesthetic blockade: A correlation between magnetic resonance imaging, ultrasound imaging, reconstructed cross‐sectional anatomy and cross‐sectional histology

Abstract

The interfascial thoracic wall blockades Pecs I and Pecs II are increasingly applied in breast and axillary surgery. Despite the clear anatomical demarcations depicted at their introduction, the clinical outcome is more variable than would be expected based upon the described anatomy. In order to elucidate factors that explain this variability, we evaluated the spread of each injectionmedial Pecs I, lateral Pecs I, the deep injection of the Pecs II-separately. A correlation of in vivo landmarks and ultrasound images with ex vivo ultrasound, reconstructed anatomical planes, histology and magnetic resonance imaging. The medial Pecs I, similar to the sagittal infraclavicular block positioning with needle position medial to the pectoral branch of the thoracoacromial artery, reaches the medial and lateral pectoral nerves. The lateral Pecs I, below the lateral third of the clavicle at the level of the third rib with needle position lateral to the pectoral branch of the thoracoacromial artery, additionally spreads to the axilla and reaches the intercostobrachial nerve. The deep Pecs II injection spreads to the lateral cutaneous part of the III-VI intercostal nerves and reaches the long thoracic nerve. The variability of the Pecs anesthetic blockades is driven by the selected Pecs I approach as only the lateral approach stains the intercostobrachial nerve. The pectoral branch of the thoracoacromial artery can serve as the landmark to differentiate the needle position of the medial and lateral Pecs I block. Clin. Anat. 32:421-429, 2019.

The role of serratus anterior plane and pectoral nerves blocks in cardiac surgery, thoracic surgery and trauma: a qualitative systematic review

“…). The seven cohort studies published in the peer‐reviewed literature had a median (IQR [range]) score of 7 (7–7 ) on the 9‐point Newcastle‐Ottawa Scale, whereas the six cohort studies published as abstracts or posters had a median (IQR [range]) score of 6 (5.25–6 ) (see also Supporting Information, Table S2).…”

“…that a pre‐incisional single‐injection serratus anterior plane block improves early post‐thoracotomy analgesia compared with systemic analgesia alone . The serratus anterior plane block group had significantly lower pain scores up to 9 h postoperatively (median [range] scores ranging from 1 [0–3] to 3 [0–5] vs. 2 [0–5] to 4 ; IQR not reported); and lower 24‐h opioid requirements. This is supported by level 3 evidence from a retrospective study comparing postoperative deep serratus anterior plane block with systemic opioids alone in 40 patients .…”

“…Park et al. compared pre‐operative deep serratus anterior plane block with no block and reported significantly lower median (IQR[range] pain scores in the intervention group at all time‐points up to 24 h postoperatively (maximum scores ranging from 2 (2–3 ) to 5 (3–7 ) vs. 4 (3–7 ) to 6 (5–7 ), respectively), a 33% reduction in 24‐h opioid requirements and greater satisfaction with analgesia. The length of hospital stay was similar in both groups.…”

Ultrasonography‐guided anterior approach for axillary nerve blockade: An anatomical study

“…The LPN, which lies in the interpectoral space (Blanco, ), contributes to the innervation of both the shoulder joint capsule and the acromioclavicular joint (Wrete, ; Aszmann et al, ; Tran et al, ). The injection of anesthetic drugs into the interpectoral space, called the Pecks blockade, is a safe technique for pain control in breast surgery and some of its variants can reach the LPN with minimal involvement of other nerves (Blanco, ; Pérez et al, ; Versyck et al, ). Therefore, a triple approach (AN, SSN, and LPN) could be used when combined AN and SSN block is not enough to provide full pain relief.…”

Clarification on chronic pain – a painfully persistent problem?

“…However, the description of the blocks’ performance is unclear and lacks details of level of block, probe position and orientation and needle direction, all important factors required to interpret the results. For example, a recent anatomical study of the Pecs blocks showed that the site of injection influences the effectiveness of the block as it determines the extent of spread, and consequently mass of local anaesthetic, reaching target nerves .…”