Ultrasound-Guided Bilateral Thoracic Paravertebral Blocks as an Adjunct to General Anaesthesia in Patients Undergoing Reduction Mammoplasty: A Historical Cohort Study

The objective was to assess whether addition of ultrasound-guided TPVBs to general anaesthesia (GA) could postpone time to first pain and improve postoperative analgesia in patients undergoing bilateral reduction mammoplasty.

Design: A historical cohort study. Patients: Of the 70 female patients who underwent bilateral reduction mammaplasty, 64 patients had complete data in the acute pain/regional anaesthesia database.

Intervention: Standard monitoring was applied before any anesthetic techniques were performed. All patients were given sedation in the form of midazolam 1-2 mg and fentanyl 50-100 µg. Patients underwent bilateral reduction mammaplasty were distributed to two groups due to their data: 1) Patients received only general anaesthesia (GA) were included in Group GA, and 2) Patients received preoperative US-guided TPVBs as an adjunct to GA were included in Group TPVBs. Thirty patients were in Group GA. Thirty-four patients who were in Group TPVBs received bilateral single injection ultrasound-guided TPVBs with 20 mL bupivacaine 0.375% (20 mL per injection) at the level of T3-4, as an adjunct to GA. Patients in both groups were administered intraoperative fentanyl if heart rate or mean arterial pressure increased >20% above pre-induction values. They also received postoperative tramadol 1mg/kg in the postoperative care unit (PACU) and rescue analgesics as metamizole sodium 4x1g and/or paracetamol 3x1g on wards, if numeric rating scale (NRS) was ≥4.

Main outcome measures: The primary endpoint was time to first pain after the surgery. Secondary endpoints were intra- and postoperative opioid and other rescue analgesic requirements, length of stay in the PACU, pain scores, incidence of postoperative nausea and vomiting (PONV), and patient and surgeon satisfaction through the postoperative first 2 days.