Background: Harmonic instruments are becoming popular in head and neck surgeries. In this prospective, randomized study, the efficacy of the harmonic instruments and electrosurgical technique is compared.

Materials and methods: A total of 48 patients undergoing unilateral neck dissection were divided into two groups. In one group, surgery was performed using conventional hemostatic instruments while in the other, only harmonic instruments were used. The two techniques were then compared with regard to intra- and post-operative blood loss, complications in operating time, drain, tracheotomy and nasogastric tube duration, and post-operative hospital stay.

Results: Differences in operative time (P = 0.647), total suction drainage (P = 0.362) and time that drains (P = 0.404), nasogastric tube (P = 0.378), and tracheotomy (P = 0.052) were kept in place and proved not significant. The average blood loss during surgery was significantly greater in the CH group (P = 0.003) as the number of hemoclips and resorbable ligature used (P = 0.002).

Conclusions: In contrast to what has been reported up to now, our study did not reveal a net advantage in the use of harmonic instruments with respect to classical instruments in terms of surgical outcome. On the contrary, harmonic tools had a higher complication rate (i.e., salivary fistula and lymphatic leak) probably due to the decreased ability of this instruments to permanently close glandular structures and lymphatic ducts. In these cases, a closure technique such as electrocautery or classic knot-tying should be used.