Preoperative flap-site injection with ropivacaine and epinephrine in BABA robotic and endoscopic thyroidectomy safely reduces postoperative pain

Background: Clinical trials on bilateral axillo-breast approach (BABA) thyroidectomy show that levobupivacaine and ropivacaine significantly reduce postoperative pain, but they focused on BABA robotic thyroidectomy only and did not identify specific sites of significant pain relief. Our objective was to assess the pain reduction at various sites and safety of ropivacaine-epinephrine flap injection in BABA thyroidectomy. Methods: This prospective double-blinded randomized controlled trial was conducted in compliance with the revised CONSORT statement (ClinicalTrials.gov registration no. NCT02112370). Patients were randomized into the ropivacaine-epinephrine arm or control (normal saline) arm. Results: From January 2014 to May 2016, 148 patients participated. The primary endpoint was site-specific pain, as measured by numeric rating scale 12hours after surgery. The ropivacaine-epinephrine group exhibited significantly less swallowing difficulty (P=.008), anterior neck pain (P=.016), and right (P=.019) and left (P=.035) chest pain. Secondary endpoints were systolic (P=.402), diastolic (P=.827) blood pressure, and pulse rate (P=.397) after injection before incision and during surgery. The vital signs of the groups just after injection did not differ. During surgery, the ropivacaine-epinephrine patients had higher pulse rates (99±13.3 vs 88±16.1, P<.001) but within normal range. There were no adverse events such as postoperative nausea and vomiting. There was no significant difference in pain scores in either patient group between patients who underwent robotic or endoscopic interventions. Conclusion: BABA flap-site injection with ropivacaine and epinephrine mix before incision effectively and safely reduced postoperative pain. Future studies should focus on tailoring ropivacaine and epinephrine dosage for individuals.