Electrosurgery plays an important role in veterinary procedures by helping surgeons control bleeding, cut tissue, and improve surgical efficiency. Dr. Brandy Willeford, Thrive Pet Healthcare's national specialty director of surgery, explains the differences between monopolar and bipolar electrosurgery and vessel-sealing devices, including their applications, limitations, and safety considerations. Her article appeared in the November issue of Veterinary Practice News.
Learning About Electrosurgery
Understanding the differences between electrosurgical devices can help surgeons use them more effectively and safely.
Good surgery requires good hemostasis. As we learn in veterinary school, meticulous hemostasis is one of the basic principles of surgery. Controlling bleeding minimizes blood loss, reduces tissue trauma, maintains visibility of the surgical field, and can ultimately make a procedure more efficient.
Electrosurgery is one tool that can help surgeons accomplish these goals. Studies in both veterinary and human medicine have demonstrated decreased blood loss with electrosurgical techniques for tissue incision compared with traditional scalpel incisions. Other studies have demonstrated reductions in surgical time with electrosurgical techniques.
For practices considering an upgrade to their surgical equipment, electrosurgery can be a valuable addition to the surgical suite. However, not all electrosurgical devices work the same way, and understanding the differences between monopolar, bipolar, and vessel-sealing devices can help surgeons use them more effectively and safely.
What is electrosurgery?
Electrosurgery uses electrical current to cut tissue or achieve hemostasis. The electrosurgical generator produces an electrical waveform that is delivered to the tissue through an active electrode. Depending on the waveform and the way the current is delivered, the result can be tissue cutting, coagulation, or vessel sealing.
Electrosurgery should not be confused with electrocautery, which uses electricity to heat an instrument that is then applied to tissue, much like a small branding iron. When using this device, electrical current itself does not pass through the patient. With electrosurgery, current is applied directly to tissue.
The two primary electrosurgical circuits are monopolar and bipolar. Vessel-sealing devices are an advanced form of bipolar electrosurgery.
Monopolar electrosurgery
Monopolar electrosurgery is probably the most familiar form of electrosurgery in veterinary practice. The system uses a pencil-like handpiece with an active electrode at its tip and requires a dispersive or grounding pad. The electrical current travels from the active electrode through the patient's tissue to the dispersive pad and back to the generator.
Monopolar electrosurgery typically has cutting and coagulation functions. Cutting uses a continuous waveform that vaporizes tissue, allowing the electrode to create an incision, while coagulation uses an interrupted waveform that heats tissue in bursts, promoting protein denaturation and hemostasis. Coagulation energy can be applied directly to tissue or to a vessel grasped with a metal instrument when more precise hemostasis is needed.
A variety of monopolar handpieces and tips are available, including blade and needle-style electrodes. Reusable handpieces may be appropriate when sterilized according to the manufacturer's instructions, including any stated limits on autoclave cycles.
About Brandy Willeford, DVM, MS, DACVS-SADr. Brandy Willeford is a board-certified veterinary surgeon and the medical director at
Advanced Veterinary Care in Salt Lake City, Utah, a Thrive Pet Healthcare partner. In addition to her clinical and hospital leadership roles, Dr. Willeford serves as Thrive Pet Healthcare's National Specialty Director of Surgery, supporting surgical teams and specialty care across the organization. Willeford is actively involved in the American College of Veterinary Surgeons and currently serves on the Certification Council. Her clinical interests include oncologic and urogenital surgery, wound management, acute and chronic pain management, and mentorship and leadership in veterinary medicine.
