The use of the harmonic scalpel vs conventional knot tying for vessel ligation in thyroid surgery

Hypothesis: The technique of thyroidectomy has undergone little change in several decades. The harmonic scalpel, using ultrasonic frictional heating to ligate vessels, is widely used in laparoscopic surgery, but there is little experience in open thyroidectomy. We hypothesized that the use of the harmonic scalpel could lead to a significant reduction in operative time as compared with knot tying in thyroid surgery. Design: Retrospective case-controlled study. Setting: Teaching institution. Patients: One hundred seventy-one consecutive patients undergoing lobectomy or total thyroidectomy by one surgeon (A.E.S.). Interventions: Eighty-six patients underwent thyroid surgery with the conventional clamp-and-tie technique (lobectomy, n = 49, total thyroidectomy, n = 36) and 85 with the harmonic scalpel (lobectomy, n = 38; total thyroidectomy, n=47). Main Outcome Measures: Demographics, pathological characteristics, thyroid size, operative time, blood loss, and complications using a 2-tailed t test, chi(2) test, and Wilcoxon rank sum test. Results: The 2 groups were similar regarding age and sex. There were no intraoperative complications. Mean +/- SD thyroid size tended to be larger in the harmonic scalpel group for both lobectomy (5.1 +/- 2.6 cm vs 4.2 +/- 2.2 cm; P=.06) and total thyroidectomy specimens (6.3 +/- 3.8 cm vs 4.8 +/- 2.9 cm; P=.08) compared with the conventional technique. Mean SD operative time was shorter in the harmonic scalpel group compared with the conventional technique group for both lobectomy (89 20 minutes vs 115 25 minutes; P<.01) and total thyroidectomy (132 39 minutes vs 161 42 minutes; P<.01) procedures. There was no difference between the 2 techniques regarding the amount of blood loss for different procedures. There was no effect of tumor size on operative time (Pearson correlation factors: 0.14 for total, 0.21 for unilateral thyroidectomy). Conclusions: The use of the harmonic scalpel for the control of thyroid vessels during thyroid surgery is safe, and it shortens the operative time by almost 30 minutes compared with the conventional technique for both unilateral lobectomy or total thyroidectomy procedures.