Comparison of the harmonic scalpel and the ultrasonic surgical aspirator in subsegmental lung resections: an...

In this study, we evaluated the effectiveness of two devices using ultrasonic energy for dissection of lung parenchyma in an experimental animal model by comparing the two methods with each other.

Twenty New Zealand rabbits were used. One-lung ventilation was obtained under direct vision and the left lung was collapsed. The rabbits were ventilated with pressure-controlled ventilation during the experiment, beginning with a pressure level of 10 cmH(2)O. After a 1 x 1-cm pulmonary wedge resection of part of the collapsed left lung using a harmonic scalpel (group A) or an ultrasonic surgical aspirator (group B), the left lung was inflated and the pressure level was increased by 5 cmH(2)O every five minutes. The pressure level which caused an air leak from the resection surface was recorded. The morphological damage to the lung parenchyma was evaluated under light microscopy.

The mean value of airway pressure levels that resulted in an air leak from the resection surface was 32.5 +/- 9.2 cmH(2)O for group A and 24.5 +/- 2.9 cmH(2)O for group B, and the difference between the two groups was statistically significant. The mean level of coagulation necrosis was 558.6 +/- 380.8 microns (133 - 1064 microns) for group A. No tissue damage to pulmonary parenchyma was observed in group B.

The harmonic scalpel can be safely used in peripheral lung resections without needing any other method to ensure hemostasis and air tightness. The ultrasonic surgical aspirator can be used for the dissection and resection of deeper lesions and preserves more lung tissue but requires additional interventions for control of the air leak from the resection surface.