Page 158 - Clinical Manual of Small Animal Endosurgery

146 Clinical Manual of Small Animal Endosurgery

(a)

(b)

Fig. 5.9 The Harmonic Scalpel is being used for laparoscopic ovariectomy.
(a) Transection of the left proper ovarian ligament. (b) Transection of the
right ovarian pedicle and suspensory ligament.

to each other and forming a ‘sticky coagulum’ at low temperatures
(Thompson and Potter, 1999). When energy is applied for a longer time,
the temperature in the tissue continues to rise and protein is denatured,
resulting in tissue coagulation. Tissue is stretched during the coagulation
process and the blade cuts through it, resulting in haemostasis with
minimal lateral thermal damage (Fig. 5.9). The technique for using the
Harmonic Scalpel is slightly different from that used with bipolar devices.
The jaws are applied across the tissue and, as energy is applied, slight
traction is placed on the device to enhance tissue dissection.
During laparoscopic ovariectomy the ovarian pedicle and suspensory
ligament are ligated and transected first. Transection of the fallopian tube