[Gravity or suction drainage in thyroid surgery? Control of efficacy with ultrasound determination of residual hematoma].

In a prospective randomized trial, the common high-vacuum drainage system according to Redon was compared with the nonsuction system according to Robinson in 80 patients undergoing elective thyroid surgery between January 1995 and August 1995. Forty patients were provided with nonsuction, passive drains, and another 40 patients were allocated to a control group with the high-vacuum system. Twenty-four h postoperatively, the wound area was analyzed by sonography after drainage removal. The dimension of the remaining hematoma was determined by scanning the operation field in six to seven layers (thickness per layer T = 1 cm). The area (A) of the hematoma was measured per layer, and thus the volume was determined by the formula: V = T x (A1 + A2.. + A(n)). Simultaneously, the quantity of discharge was determined. Patients receiving nonsuction drainage had significantly lower median drainage volume (34 ml; range: 0-175 ml vs-115 ml; range: 40-346 ml; P < 0.01) and a remaining hematoma, measured sonographically, of similar volume to that of the patients receiving high-vacuum treatment (4.4 ml; range: 0-21.7 ml vs 5.3 ml; range: 0.6-24.9 ml; not significant). No complications were observed. An advantage to using the nonsuction device is seen with respect to similar resting wound hematoma, lower fluid evacuation, and painless drain removal. This study supports prophylacity routine nonsuction wound drainage after elective thyroid surgery.