Electrosurgery (ESU) Machine

What is an electrosurgical Unit (ESU) 

An electrosurgical unit (ESU) is a medical device used to perform surgical procedures with the help of high-frequency electrical currents. It works by using an electrical generator to produce an alternating current that passes through a hand-held electrode or instrument, creating heat that can be used to cut, coagulate, or ablate tissue.

The ESU is commonly used in a variety of surgical specialties, including general surgery, neurosurgery, gynecology, urology, and plastic surgery. It can be used for a range of procedures, from simple skin biopsies to more complex operations such as hysterectomies and brain surgeries.

ESUs come in different types and configurations, with varying power settings, modes, and accessories. Some units are designed for open surgery, while others are specifically intended for minimally invasive procedures such as laparoscopy and endoscopy.

As with any surgical device, the ESU must be used with care and proper training to minimize the risk of complications such as burns, tissue damage, and electrical shock.

Electrosurgical units (ESUs) are commonly used to cut and coagulate tissue. ESUs can support both monopolar and bipolar methods of electrosurgery. The key difference between monopolar and bipolar electrosurgery lies in how the electrical current flows and completes the circuit.

In monopolar electrosurgery, the electrical current passes through the connected device (active electrode) directly to the affected tissue, where the desired tissue effect occurs. It then travels through the patient's body to a dispersive pad electrode, which receives the current and transmits the energy back to the ESU to complete the circuit. This method is more frequently used, but it has the potential to cause adverse effects due to the current passing through the patient's body.

Bipolar electrosurgery, on the other hand, delivers the electrical current directly to the affected tissue through an active electrode, such as a bipolar probe. The same device then returns the current back to the ESU, without the need for a dispersive electrode. This method is less commonly used, but it can be advantageous in certain situations, such as when the patient has implanted lifesaving devices that may be adversely affected by the monopolar current.

In conclusion, both monopolar and bipolar methods of electrosurgery have their advantages and disadvantages. The choice of method depends on the specific circumstances and the preference of the physician performing the procedure.

 

 

Mono-polar Electrosurgery

Bipolar Electrosurgery

What is Crest Factor in Electrosurgery 

In electrosurgery, the crest factor refers to the ratio of the peak voltage to the root-mean-square (RMS) voltage of the electrical signal used for tissue cutting or coagulation. The crest factor is an important parameter in electrosurgery as it can affect the quality of the surgical outcome and patient safety.

A high crest factor indicates a waveform with a high peak-to-average ratio, meaning that the voltage can spike very high, very quickly. In electrosurgery, this can lead to the generation of excessive heat and tissue damage, which can result in poor wound healing and patient discomfort. A low crest factor, on the other hand, indicates a waveform with a flatter peak-to-average ratio, which can result in a more controlled and precise tissue effect.

Therefore, the crest factor of the electrosurgical waveform is an important consideration when selecting an appropriate waveform for a given surgical application. It is often used in conjunction with other waveform parameters such as frequency and duty cycle to achieve the desired surgical effect while minimizing tissue damage and patient discomfort.

 

So finally the crest factor (CF) is a measure of the electrosurgical unit's ability to coagulate tissue without causing excessive cutting or thermal damage. It is based on the principle of selectively shrinking the top layer of tissue to seal and prevent blood loss from capillaries while minimizing damage to surrounding tissue. CF values range from 1.4 for a pure sine wave to approximately 10 for effective coagulation.

 

For waveforms with a continuous current setting or pure sinewave (100% on), the CF is defined as the ratio betweem peak voltage and RMS.

CF = Vp/VRMS

For the other waveforms, the crest factor is defined as the ratio between peak-to-peak voltage and 2 x the RMS voltage.

CF = Vpp/2 x VRMS

 

Advantages of Electrosurgery Machine,

1. Precise cutting: Electrosurgical instruments can make precise incisions and cuts with minimal damage to surrounding tissue, resulting in less scarring and a faster recovery.

2. Coagulation: Electrosurgery can quickly and effectively stop bleeding by coagulating the blood vessels in the surgical area, reducing the risk of hemorrhage and the need for additional suturing.

3. Reduced blood loss: By coagulating blood vessels, electrosurgery can reduce the amount of blood loss during a surgical procedure.

4. Reduced surgical time: Electrosurgery can often reduce the time it takes to perform a surgical procedure, which can reduce anesthesia time and overall surgical stress on the patient.

5. Enhanced visibility: Electrosurgery can provide enhanced visibility during a procedure by reducing the amount of blood in the surgical field, making it easier for surgeons to see what they are working on.

6. Versatility: Electrosurgical instruments can be used for a wide variety of surgical procedures, making them a versatile tool for surgeons.

Overall, electrosurgery can provide significant benefits to both patients and surgeons by reducing surgical time, blood loss, and scarring, while improving surgical precision and outcomes.

Safety precautions need to be considered with electrosurgery

Electrosurgery carries some inherent risks and requires several safety precautions to minimize them. The following are some of the safety precautions that need to be considered during electrosurgery:

1. Proper grounding and insulation: A proper ground connection is essential to prevent electrical current from flowing through unintended pathways. Electrosurgical units must be properly grounded, and all cables and accessories must be insulated and in good condition.

2. Adequate patient preparation: Proper patient preparation is essential for safe electrosurgery. This includes proper skin preparation and ensuring that the patient is not in contact with any conductive material that may cause current to flow through unintended pathways.

3. Proper electrode placement: The electrodes used during electrosurgery must be placed correctly to avoid unintended tissue damage or injury to adjacent structures.

4. Surgeon training: Electrosurgery should only be performed by trained and experienced surgeons who are familiar with the equipment and its proper use.

5. Monitoring: Continuous monitoring of the patient's vital signs, such as heart rate, blood pressure, and oxygen saturation, is essential during electrosurgery to detect any adverse effects and ensure patient safety.

6. Fire prevention: Electrosurgery can create a spark, which can ignite flammable materials. Therefore, all flammable materials, such as alcohol-based skin preparations, should be removed or kept away from the surgical site.

7. Device maintenance: Electrosurgical units and accessories must be properly maintained and inspected regularly to ensure they are in good working condition and safe to use.

By following these safety precautions, the risks associated with electrosurgery can be minimized, and the procedure can be performed safely and effectively.