THE COMBINATION OF ULTRASOUND-GUIDED PECTORAL NERVES II AND PARASTERNAL BLOCKS AS A VALID ALTERNATIVE FOR ANESTHESIA IN BREAST SURGERY: AN OBSERVATIONAL STUDY
Authors: Basso Ricci Erika 
Published: May 2021

Background: Breast cancer surgery is often associated
with severe postoperative pain that may
compromise systemic homeostasis, which increases
perioperative morbidity, the length of stay in the hospital,
and costs. Scientifi c evidence has also shown
that an inadequate analgesia could promote the risk
of persistent pain development after breast surgery.
Objective: Recent literature suggested that the
pectoral nerves II (PECS II) block may represent
a valid alternative to general anesthesia (GA) and
conventional, regional techniques for analgesia in
breast surgery. This technique may provide complete
anesthesia of the lateral part of the thorax but cannot
block, by itself, the anterior cutaneous branches of
the intercostal nerves. The combination of a parasternal
block (PSB) and a PECS II block has been
performed as a single anesthetic technique.
Study Design: This is an observational, monocenter,
prospective, and cohort study. We obtained
the approval of our scientifi c ethic committee and
clinical trials registration.
Setting: This study enrolled patients undergoing
an elective breast surgery. In particular, we enrolled
patients who were scheduled for a mastectomy or
quadrantectomy of the medial part of the breast.
Methods: We recruited 40 patients who were
scheduled for breast surgery. A PECS II block was
performed with an injection of ropivacaine 0.5%
20 mL + 10 mL. Then, a PSB was performed by 2
separate injections of 3 mL of 0.5% ropivacaine,
for each one, at the level of the second and fourth
intercostal space. All of the patients received intraoperative
sedation and multimodal analgesia. During
the intraoperative period, the accessory need of a
local anesthetic infi ltration, conversion to GA, and
the total amount of propofol required to maintain
good comfort of the patients were recorded. In the
fi rst 24 postoperative hours, every 6 hours, postoperative
pain was assessed by an investigator using
a numerical rating scale (NRS). The consumption
of analgesic and antiemetic drugs and the incidence
of postoperative nausea and vomiting (PONV) were
also recorded.
Results: Our observational analysis yielded 40
patients in a period of 6 months. The population was
subdivided into 2 groups: a mastectomy group or a
quadrantectomy group. All of the population reported
their pain scores at rest (rNRS < 3) and during activity
(iNRS < 5) in the postoperative period. None of
the patients required GA. Six patients (27.3%) in the
mastectomy group required a supplemental anesthetic
infi ltration. Eleven (27.5%) patients required a
rescue analgesic drug: 9 (40.9%) in the mastectomy
group and 2 (11.1%) in the quadrantectomy group.
Two patients reported events of PONV, one for each
group (4.54% for the mastectomy group and 5.55%
for the quadrantectomy group). No complications
occurred.
Conclusion: This study indicates the safety and
feasibility of the novel ultrasound-guided thoracic
wall blocks during inpatient and outpatient breast
surgery for the management of intraoperative anesthesia
and postoperative analgesia.
Limitations: This is an observational study; a randomized
control trial is mandatory to confi rm the
results.
Key words: Breast cancer surgery, pectoralis nerve
block, parasternal block, ultrasound-guided anesthesia,
regional anesthesia, pain control