Harmonic scalpel versus conventional resection in thyroid surgery: a meta analysis on the safety outcomes

Objective To compare the safety between harmonic scalpel and conventional resection in total or near total thyroidectomy with recta-analysis. Methods The prospective randomized controlled studies were searched for in electronic databases （MEDLINE, EMBASE, Cochrane Library）. Meta analysis of acquired data was performed through the use of RevMan 5.2 software. Results According to the inclusion criterion, 13 articles were enrolled which compared on the safety between harmonic scalpel and conventional resection in thyroid surgery. A total of 1620 patients with thyroid tumor were enrolled, including 802 patients in harmonic scalpel group and 818 patients in conventional resection group. Compared with conventional resection group, the harmonic scalpel group showed shorter time of surgery, the weighted mean difference （WMD） and their 95% confidence interval （95%CI） was -21.06 [-25.65, -16.47], Z = 8.99, P < 0.00001; less intra-operative blood loss, WMD and 95% C1 was -14.36 [-20.67, -8.06], Z = 4.46, P < 0.00001; less post-operative drain output （WMD and 95% CI was -7.47 [-11.35, -3.58], Z = 3.77, P = 0.0002）; less hospitalization charges （WMD and 95% CI was -117.97[-131.65, -104.29], Z = 16.90, P < 0.00001）. The incidence of postoperative transient recurrent laryngeal nerve dysfunction and transient hypocalcemia were similar in both groups. Conclusion Using the harmonic scalpel in thyroid surgery was as safe as that of the conventional technique with the advantage of shorter time of surgery, less intraoperative blood loss and less postoperative drain output. Key words: Thyroid neoplasms; Thyroidectomy; Sonication; Meta-analysis