Guide
Ultrasonic Scalpel vs Electrocautery (Diathermy) in Veterinary Surgery
An ultrasonic scalpel cuts and coagulates soft tissue with high-frequency mechanical vibration at the instrument tip. Electrosurgery — also called electrocautery or diathermy in many clinics — delivers electrical current through monopolar, bipolar or vessel-sealing configurations. The two modalities serve overlapping soft-tissue workflows, but they are different energy mechanisms: choose by procedure, access and the tissue effect you need, and many hospitals keep both systems available.
Mechanism: mechanical vibration vs electrical current
How an ultrasonic scalpel works
An ultrasonic surgical system drives a blade longitudinally at ultrasonic frequency. Frictional heat at the tissue contact surface supports cutting and coagulation with low smoke. ReinnoVet UG-100 and RBK-200 operate at 55.5 kHz with working temperatures below 100 °C and thermal spread under 1 mm in the manufacturer's porcine study. The systems use reusable ADV ultrasonic blades with 14 / 23 / 36 cm shaft length.
How electrosurgery (diathermy) works
Electrosurgical platforms deliver high-frequency electrical energy. Monopolar mode uses an active electrode at the surgical site and a return electrode on the patient. Bipolar mode passes current between the two jaws of an instrument. Vessel-sealing mode applies controlled bipolar energy to seal vessels and tissue bundles, with feedback that can stop energy delivery when the seal is complete. ReinnoVet EP-200 provides monopolar, bipolar and large-vessel sealing functions and seals veins, lymphatic vessels and tissue bundles up to 7 mm in diameter.
Side-by-side comparison
| Ultrasonic scalpel | Electrosurgery (diathermy) | |
|---|---|---|
| Energy | Mechanical vibration at the blade | Electrical current (monopolar, bipolar, vessel sealing) |
| ReinnoVet systems | UG-100, RBK-200 | EP-200 |
| Frequency / power | 55.5 kHz; 45 W | 200 W |
| Vessel sealing capacity | Up to 5 mm | Veins, lymphatic vessels and tissue bundles up to 7 mm |
| Return electrode | Not used | Used in monopolar electrosurgery |
| Instruments | Reusable ADV ultrasonic blades, 14 / 23 / 36 cm shaft length | Pencils, bipolar forceps, large-vessel sealing instruments |
| Typical smoke | Low; published canine Lap OVE comparisons still report more smoke with ultrasonic dissectors than with vessel sealers | Varies by mode; vessel sealing produced less smoke than ultrasonic dissection in one paired study |
When each is used in veterinary soft-tissue surgery
Ultrasonic systems are often chosen when the surgeon wants one instrument that cuts and seals, with limited thermal spread and no return electrode. Typical soft-tissue uses include spay and neuter (including laparoscopic ovariectomy / desexing), mammary tumor surgery, urologic procedures and other minimally invasive work where an ultrasonic blade can reach the target.
Electrosurgery is often chosen when the team needs monopolar cutting and coagulation, bipolar work and dedicated vessel sealing in one platform. Vessel sealing is commonly used for pedicles and tissue bundles in open and laparoscopic soft-tissue surgery, including haemostasis (hemostasis) during spay, mass removal and general soft-tissue dissection.
Many hospitals keep both modalities. Ultrasonic and electrosurgical systems are not interchangeable technologies; equipment planning should match the procedure mix, instrument preference and training of the surgical team.
What published studies report
Published randomized comparisons in canine laparoscopic ovariectomy (Lap OVE) have evaluated ultrasonic dissectors and bipolar vessel-sealing devices. Device brand names appear here only as they appear in the source papers.
| Study | Design | Finding (speed / bleeding / smoke / thermal) | Source |
|---|---|---|---|
| Öhlund et al., J Small Anim Pract, 2011 | 10 dogs; each ovary assigned to LigaSure or SonoSurg | Surgical time and intraoperative complications did not differ significantly; both devices were effective and easy to use | https://doi.org/10.1111/j.1748-5827.2011.01060.x |
| Spillebeen et al., Vet Surg, 2017 | 22 dogs; paired ovaries, Sonicision vs LigaSure | Vessel sealer excised ovaries faster (2.0 vs 2.9 min); ultrasonic device produced more smoke; minor pedicle haemorrhage was easily managed; collateral thermal damage did not differ | https://doi.org/10.1111/vsu.12640 |
| Forbes & Monnet, Am J Vet Res, 2023 | 10 dogs; one ovary each with Sonicision vs vessel sealer | Median ovary-removal times similar (96 s ultrasonic vs 110 s vessel sealer); no intraoperative complications with either device | https://doi.org/10.2460/ajvr.23.05.0112 |
These studies compare modalities in one elective procedure. Results should not be averaged across papers or extrapolated to every soft-tissue case. Cost conclusions in the source papers are not summarized here.
ReinnoVet systems: EP-200, UG-100 and RBK-200
EP-200 electrosurgical platform. High-frequency electrosurgery with monopolar, bipolar and large-vessel sealing. 200 W. Seals veins, lymphatic vessels and tissue bundles up to 7 mm. Real-time impedance monitoring with automatic stop when the seal is complete. Dual monopolar ports. CE marked, certificate available on request. Power configuration can be set to local requirements. EP-200 product page
UG-100 and RBK-200 ultrasonic surgical systems. 55.5 kHz; 45 W; seals vessels up to 5 mm; thermal spread under 1 mm (manufacturer porcine data). MAX, MIN and ADV modes. Reusable ADV ultrasonic blades, 14 / 23 / 36 cm shaft length — reusable blades help clinics lower per-procedure cost. Indications in the product manual include minimally invasive surgery. CE marked, certificate available on request. Power configuration can be set to local requirements. UG-100 page RBK-200 page
FAQ
Is diathermy the same as electrocautery?
In veterinary practice the terms electrocautery, electrosurgery and diathermy are often used for the same family of high-frequency electrical energy systems. Strictly speaking, true electrocautery heats a wire by current that does not pass through the patient, while electrosurgery / diathermy passes current through tissue. On this page we treat the clinic terms as referring to electrosurgical platforms such as EP-200.
How does an ultrasonic scalpel work?
An ultrasonic scalpel vibrates a blade at ultrasonic frequency so that mechanical energy at the tip cuts and coagulates soft tissue. ReinnoVet UG-100 and RBK-200 operate at 55.5 kHz with reusable ADV ultrasonic blades in 14 / 23 / 36 cm shaft lengths.
Which causes less thermal spread?
Manufacturer data for UG-100 / RBK-200 report thermal spread under 1 mm in a porcine study. Published canine Lap OVE comparisons of ultrasonic dissectors and vessel sealers found no significant difference in collateral thermal damage between the devices tested. Choose by the procedure and the system in use, not by a single number.
Can one modality replace the other?
No. Ultrasonic and electrosurgical systems use different energy mechanisms and support different instrument sets. Many hospitals use both across open and minimally invasive soft-tissue surgery.
Do ultrasonic systems need a return electrode?
No. Ultrasonic systems do not use a patient return electrode. Monopolar electrosurgery does.
What vessel sizes can ReinnoVet systems seal?
UG-100 and RBK-200 seal vessels up to 5 mm. EP-200 seals veins, lymphatic vessels and tissue bundles up to 7 mm.
What certification do these systems have?
CE marked, certificate available on request.
Internal links
Talk to our team about ultrasonic and electrosurgical systems
Request product information on EP-200, UG-100 or RBK-200, or ask about becoming a distributor.
References
- Öhlund M, Höglund O, Olsson U, Lagerstedt AS. Laparoscopic ovariectomy in dogs: a comparison of the LigaSure and the SonoSurg systems. J Small Anim Pract. 2011;52(6):290-294. https://doi.org/10.1111/j.1748-5827.2011.01060.x
- Spillebeen AL, Janssens SSDS, Thomas RE, Kirpensteijn J, van Nimwegen SA. Cordless ultrasonic dissector versus advanced bipolar vessel sealing device for laparoscopic ovariectomy in dogs. Vet Surg. 2017;46(4):467-477. https://doi.org/10.1111/vsu.12640
- Forbes JN, Monnet E. A vessel sealing device and an ultrasonic dissector are equally effective and safe for single port laparoscopic ovariectomy in dogs. Am J Vet Res. 2023;84(10). https://doi.org/10.2460/ajvr.23.05.0112
- ReinnoVet Product Brochure (EN). Specs for EP-200, UG-100 and RBK-200 as cited above.