This meta-analysis compared harmonic scalpel and LigaSure® systems with the conventional clamp-and-tie technique in thyroidectomy. Medline, Cochrane, EMBASE, and Google Scholar databases were searched until December 30, 2015. Randomized controlled studies (RCTs) or two-arm prospective studies were included. The primary outcome was operation time. The data were evaluated both by pair-wise meta-analyses and network meta-analysis within a Bayesian framework using Markov chain Monte Carlo methods. Compared with the conventional hemostasis, there was a significant reduction in operation time with harmonic scalpel (HS) and LigaSure (LS) (difference in means = -24.27 min, 95 % CI -28.11 to -20.44 min, P < 0.001; and difference in means = -13.08 min, 95 % CI -16.88 to -9.27 min, P < 0.001, respectively). For total thyroidectomy and hemi-thyroidectomy, subgroup pair-wise meta-analyses found a reduction of 26.31 and 21.90 min in operation time for harmonic scalpel, and a reduction of 12.77 and 17.48 min for LigaSure, respectively. Among studies with mixed total and hemi-thyroidectomy, no significant difference in operation time was seen between harmonic scalpel and the conventional hemostasis (P = 0.313). Network meta-analysis also found harmonic scalpel and LigaSure to have less operation time than the conventional hemostasis, and that harmonic scalpel was associated with a significant 9.78 min reduction in operation time than LigaSure which was not seen in pair-wise comparison. Harmonic scalpel had significantly less risk of definitive recurrent laryngeal nerve palsy, intra-operation blood loss, and post-operation bleeding than the conventional hemostasis. LigaSure was associated with significantly less intra-operative blood loss than the conventional hemostasis (P = 0.023). There was no significant difference among three different procedures in rates of transient recurrent laryngeal nerve palsy. This study found that harmonic scalpel and LigaSure decreased operation time compared with the conventional hemostasis and that harmonic scalpels was associated with the lowest operation time.
Keywords: Conventional; Harmonic scalpel; LigaSure; Thyroidectomy.