Energy surgical instruments originated in the 1920s and have been booming for a hundred years since their birth. After the 1920s,  doctors widely used electric current for tissue cutting and hemostasis. High frequency electrosurgical unit began to be commercialized and quickly became the most widely used and most valuable equipment in surgery. Energy surgical instruments also developed accordingly.

Energy surgical instruments refer to instruments that use electrical or mechanical energy to perform cutting, coagulation, hemostasis, and other operations on tissues during surgical procedures. As modern surgery develops towards minimally invasive, less damaging and faster recovery, more energy forms including radio frequency, ultrasound, plasma, laser, etc. are widely used in surgical operations, making difficult operations simple, efficient, safe and reliable.

At present, the energy forms of common energy surgical instruments in clinical practice are mainly electrical energy and mechanical energy. According to the energy type, energy surgical instruments can be divided into four types: electrical energy instruments, ultrasonic energy instruments, integrated instruments and other energy instruments. Among them, electrical energy instruments can be divided into monopolar electrical energy instruments and bipolar electrical energy instruments.

According to product type, energy surgical instruments can be divided into high-frequency, radio frequency, plasma, ultrasonic，ultrasonic bone electrosurgical unit and other products.

High-frequency electrosurgical unit is the energy surgical instrument with the longest clinical application history. Its output frequency is usually between 200kHz and 3.3MHz. It can be widely used in surgical operations such as abdominal cavity, digestive tract, head and neck, and plays a role in rapid cutting and coagulation of small blood vessels. The 4MHz radio frequency electrosurgical unit, as a supplement to high-frequency electrosurgical unit in the megahertz range, has its unique use in head and neck surgery and skin beauty.

The output frequency of plasma electrosurgical unit is lower than that of high-frequency electrosurgical unit, generally at 100kHz, which can achieve fine cutting, tissue ablation, protect surrounding tissues, and complement high-frequency electrosurgical unit. It is mainly used in otolaryngology, sports medicine, spinal surgery, and urology.

As another form of energy, ultrasonic electrosurgical unit, compared with the above several types of electric energy instruments, can coagulate thicker blood vessels while cutting efficiently and accurately, and is often used in thoracic and abdominal surgery. Ultrasonic bone scalpel applies the basic principle of ultrasonic scalpel to hard tissue cutting, achieving precise and safe bone tissue cutting in spinal and oral surgery.

In short, energy surgical instruments with different output frequencies and different energy types have completely different and irreplaceable product characteristics and clinical effects, and surgeons can choose and match them according to specific surgical conditions.

Plasma electrosurgical unit: a revolutionary technology in energy surgical instruments, from thermal energy to kinetic energy

Plasma electrosurgical unit is derived from high-frequency electrosurgical unit. It was first used in clinical practice in China in 2000. Since then, soft tissue cutting has gradually shifted from radio frequency high temperature to low temperature and safety. An excellent plasma electrosurgical unit should have the qualities of rapid plasma generation, strong applicability and high reliability.

The plasma electrosurgical unit with pulsed radio frequency technology. When the blade comes into contact with human tissue, the radio frequency electric field vaporizes and decomposes the electrolyte liquid in the tissue, and a plasma vapor layer containing free electrons, ions, neutral chemical groups and other neutral substances is generated at the tip of the blade. When the charged particles in the plasma are accelerated by the electric field, the molecular bonds of tissue cells can be broken, causing the cells to disintegrate, achieving the effect of cutting and ablation.

Working principle of plasma electrosurgical unit 

Plasma electrosurgical unit cause less thermal damage to tissues. They can precisely control energy to achieve the effect of low-temperature tissue decomposition. Compared with ordinary radio frequency equipment, plasma electrosurgical unit can cut and ablate tissues at lower temperatures (40-70°C) at lower radio frequencies (100KHz), minimizing thermal damage. In comparison, the operating temperature of other energy surgical instruments is between 350-700°C.

Currently, plasma electrosurgical unit are mainly used in otolaryngology, sports medicine, spinal surgery and urology.

High-frequency electrosurgical unit - a must-have weapon for surgeons

High-frequency electrosurgical unit is an energy surgical instrument that replaces traditional mechanical scalpels for tissue cutting. It has been used in surgical operations for more than 80 years. High-frequency electrosurgical unit applies high-frequency and high-voltage current to the patient's body through electrodes, cauterizes and cuts the tissue, cuts the lesion or stops bleeding by coagulation, and achieves cutting (separation of body tissue) or coagulation (coagulation of blood or tissue fluid).

According to different clinical needs, high-frequency electrosurgical units with various functions have appeared in the clinic, including argon electrosurgical unit, LEEP electrosurgical unit, and vascular sealing system.

Schematic diagram of high-frequency electric knife equipment改成High-frequency electrosurgical unit

Ultrasonic electrosurgical unit: a sharp sword in minimally invasive precision surgery

According to the "Medical Device Classification Catalog", ultrasonic and ultrasonic bone electrosurgical unit are both ultrasonic surgical equipment. Ultrasonic electrosurgical unit are used for cutting soft tissue and closing blood vessels, while ultrasonic bone electrosurgical unit are used for fine cutting of human bone tissue. Both are indispensable products in the field of surgery.

Ultrasonic electrosurgical unit appeared in the 1950s and began to be used clinically in the 1980s. The ultrasonic electrosurgical unit consists of a main unit, a transducer handle, an ultrasonic blade head and a foot pedal. The main mechanism of action is that the main unit outputs an electrical signal, and the transducer handle uses the electrostrictive effect or magnetostrictive effect to convert electrical energy into mechanical energy to generate high-frequency vibration. The blade head contacts tissue protein under high-frequency vibration, generating cavitation, quickly vaporizing the water in the tissue, breaking the protein hydrogen bonds, and denaturing the protein into a viscous coagulant, thereby achieving the effects of cutting, coagulating tissue and stopping bleeding.

Ultrasonic soft tissue cutting and hemostasis equipment