At first, electrosurgical units (ESUs) seemed like an expensive novelty. However, they have changed surgical practices, offering better precision and safety.

Now, ESUs are essential tools in surgery. Using various electrical energy forms, EUSs cut, coagulate, and seal tissue during surgical interventions.

These tools allow surgeons to achieve unparalleled precision during intricate procedures, reducing the risks of traditional surgery. They also help surgeons achieve the best results, lower blood loss, and improve patient recovery.

Although ESUs are common in surgeries, some are different. Because there are so many options, choosing the right one for your practice can be difficult.

This guide aims to give you knowledge about electrosurgical units (ESUs). It covers how they work, the different types, and safety tips. This information will help you make an intelligent choice when selecting the right ESU for your practice.

What is an Electrosurgical Unit (ESU)?

An electrosurgical unit (ESU) is a medical equipment that employs high-frequency electrical current to cut, coagulate, desiccate, or fulgurate tissue while performing surgery. One feature of high-frequency alternating current is the “skin effect.” This happens because electrical current prefers to travel along the path of least resistance at high frequencies.

This tends to be closer to the surface of conductive materials, including biological tissues. As the frequency of electrical current increases, the depth it can reach, called “skin depth,” decreases. This means the current stays closer to the surface of the tissue.

ESUs use the skin effect and high-frequency electrical current. This current ranges from 100 kilohertz to 5 megahertz.

Electrosurgery generates heat in or near the tissue, quickly heating it. Different temperatures can have various effects on the body.

When a tissue volume heats from average body temperature to 107.6°F (42°C) in just a few seconds, it changes chemically. These changes are completely reversible. When the temperature returns to normal, the cells usually go back to normal quickly.

However, the cytochemical changes become irreversible if the same tissue volume experiences a heat increase above 107.6°F (42°C). They inhibit normal cell functions and eventually lead to cell death.

Higher temperatures, between 107.6°F and 140°F (42-60°C), cause cell proteins to change. They lose their structure and become solid. This process is called coagulation, and it leads to tissue blanching.

Raising the temperature to 212°F (100°C) causes tissue to dry out, a process known as “desiccation.” When temperatures go above 212°F (over 100°C), the solid parts of the tissue turn into carbon. Electrosurgery uses concentrated electrical current to create heat in tissue. The results depend on the voltage and frequency used.

For example, lower voltage with continuous electrical waveforms will produce excellent cutting results as it vaporizes the tissue. On the other hand, higher voltages and interrupted waveforms with short and scarce “ON time” will make excellent coagulation. The combination of both achieves blending.

Choosing the proper effects for surgical procedures is simple. It depends on selecting the correct voltage and waveform.

Most ESUs have separate “cut” and “coagulate” modes. You can use these modes alone or together, depending on the type of surgery or other clinical needs.

ESUs are unique because they reduce the risk of complications like excessive bleeding. This bleeding often happens during surgery. They do this by sealing blood vessels as they cut through tissue. This also allows surgeons to perform said procedure to maintain a clear surgical field and optimal visualization.

Types of Electrosurgical Devices

Surgeons use ESUs in many modern surgeries. However, the units can differ significantly in usage. Some ESUs remain unused in the operating room. Surgeons also use them in many other surgical applications, including dental procedures.

An ESU’s main feature is its power output, which ranges from 10 Watts to over 300 Watts.

Many practitioners prefer units with lower power output for delicate procedures. This helps ensure precision, reduce the risk of overheating, and protect sensitive tissues from damage.

Higher power output usually leads to better and more efficient cutting. This is especially helpful in procedures that need quick and precise tissue removal. It also helps improve bleeding control.

However, higher power increases the risk of unintended tissue damage and burns if not used carefully. Below is a quick description of typical ESU models, ranked by their power output:

Desiccators and Hyfrecators

Healthcare professionals often use desiccators and Hyfrecators in-office for skin procedures, such as removing skin tags. These handheld devices, which run on batteries, have limited modes of operation and don’t need a return pad. Dermatologists commonly use them for simple skin procedures.

These devices have a limited power output, ranging between 10 and 50 Watts. However, the power output is usually easily adjustable. They also feature cut, blended cut, and pinpoint coagulation modes.

Standard Electrosurgical Units

Standard ESUs are used in various operating rooms and ambulance settings, which dictates their power and size. For example, specialists can use a 120-watt electrosurgical device, a more robust option than the desiccators and hyfrecators mentioned earlier. Ambulatory centers may use a 200-watt unit for emergency surgeries.

Full-featured operating rooms often use 300-watt ESUs. These devices are solid and provide excellent power.

Standard units also have protective features and can withstand long periods of use without problems. Common modalities associated with standard units include the cut above, blend, and coagulation variations but rely on different electrosurgical techniques.

Types of Electrosurgical Techniques: Monopolar vs. Bipolar

Electrosurgical units typically consist of a generator and a handpiece with one or more electrodes. You can control the device’s settings on the generator’s user interface. A switch on the handpiece or a foot switch delivers the electrical current.

The generators can create different electrical waveforms between 100kHz and 5MHz. These waveforms do not cause contractions in nerves and muscles. However, high voltages and frequencies can disrupt implants, especially pacemakers. Standard ESU devices often offer two modes that meet specific surgical needs and procedures.

Monopolar Electrosurgery

In monopolar electrosurgery, the electrical current is transmitted through the patient’s body through the connected handpiece (active electrode) directly to the affected tissue. It then travels through the patient’s body to where the return electrode, called a “dispersive pad,” sits. This way, the current passes through the patient’s body and completes the circuit.

The dispersive pad safely removes the current from the patient. However, the contact surface between the skin and the pad has excellent electrical resistance and produces heat. In typical applications, the size of the dispersive pad and its conductivity usually dissipate the heat.

However, improper use can lead to electrode burns on the skin or inadequate heat dissipation. Modern ESU devices have safety features that prevent burns from poor contact between the disperse pad and the patient’s skin.

Bipolar Electrosurgery

In bipolar electrosurgery, the active electrode sends an electric current through the tissue, which returns to the return electrode. Unlike in the monopolar mode, the return electrode is near the active electrode. The design resembles the tips of a pair of forceps.

Bipolar electrosurgery does not use a dispersive pad, meaning the current only passes through a small tissue area. This is especially helpful when performing coagulation. In addition, bipolar electrosurgery virtually eliminates patient buts.

Bipolar ESU works in any medium, allowing surgeons to solidify in a fluid environment. This method is sometimes called wet coagulation or “wet field cautery.”

The monopolar mode is suitable for cutting and coagulating large areas. In contrast, users employ the bipolar mode for more precise tasks. Surgeons often use it in neurosurgery or eye surgery with small tissue areas.

Modern ESUs have both modes. Knowing which one to use for safe and effective surgery is essential.

Safety Considerations for Using ESUs

While electrosurgical units are an integral part of modern surgery, they are with certain risks. Understanding these risks and following safety rules is essential. This can help prevent problems from using electrical current, like shocks, burns, or tissue damage. Here are common safety concerns and considerations that are typically associated with ESUs:

Correct Grounding

The dispersive pad, or the “patient plate,” is crucial to monopolar electrosurgery. If it is not placed correctly or does not work well, it can cause burns and injuries caused by improperly spreading of the electrical current.

Placing the dispersing pad on a large, flat body area is essential. This helps increase the contact between the skin and the pad.

The area should be free of hair, scars, or blockages, which can increase electrical resistance and cause heat. Inspecting the dispersing pad before and during the surgical procedure is always best.

Avoid Flammable Materials

ESUs produce heat and electrical sparks, igniting flammable materials in the operating room. These include alcohol-based skin preparations, surgical drapes, and even oxygen.

It’s essential to keep the area free of flammable substances and vapors. Avoid using high oxygen concentrations near the surgical field, which can increase fire risk.

Start Slow

Starting the ESU on a higher setting can generate excessive heat and cause unintended tissue damage. Controlling the precision and depth of the cut can be difficult, mainly if the surgeon has yet to use a specific model.

That’s why it’s best to start slow and use the lowest adequate power for output for the surgical procedure. Keeping the active electrode and the entire device in good condition is also essential. We recommend occasional calibration of the ESU to ensure the device’s precision.

Double-Check

In addition to checking the patient plate, ensuring that the ESU is adequately set up and working is essential. Before you use it, please check the cable and electrodes for wear or damage and replace them if worn out or damaged. Isolated power in the OR is also highly recommended to prevent electrical accidents.

All staff should receive training to use the ESU safely. They must learn how to place electrodes and, most importantly, recognize potential hazards. This training helps prevent accidents or injuries to the surgical team and the patient.

This highlights the importance of communication within the surgical team. All team members must understand how the ESU works, including the power settings used and the safety protocols that apply.

Maintenance Matters

Make sure to maintain the ESU regularly. Inspect the units, cables, and components often.

This will keep the equipment safe and working well. I checked the cables and electrodes. I calibrated the device to ensure it produced accurate power.

I also ensured that the return electrode monitoring worked correctly. This will significantly reduce the risk of the ESU malfunctioning and causing burns or electrical shocks.

Smoke Management

Electrosurgery often creates surgical smoke. This smoke can be harmful to anyone who breathes it in. It contains toxic chemicals and possibly infectious particles.

Most modern ESU systems use a surgical smoke evacuation system to prevent this, and most modern operating rooms also rely on this system to keep the space surgically smoke-free.

How to Choose the Right Electrosurgical Unit for Your Practice

When choosing the right ESU for your practice, evaluate its specifications and features. Consider your clinical needs and any limitations. This helps improve care quality and increase efficiency. Here are the most important factors to consider:

Ease of Use and User Interface (UI)

Modern ESUs have easy-to-use interfaces with large buttons. This design helps those in surgical garb navigate settings and switch modes quickly.

They often have customizable presets. These let surgeons save their favorite settings. This increases efficiency and consistency in different procedures.

Please look for a model with an ergonomically designed handpiece to ensure it doesn’t work during lengthy procedures. Intuitive controls should allow for quick adjustments. User-friendly and accessible options must be easy to reach, helping to reduce distractions during surgery.

Portability and Size

These two factors mainly depend on your practice’s needs. A smaller, handheld device may work well if you are an office care physician. However, operating rooms will benefit more from larger units. Practices with limited space should think about using a smaller unit.

This also applies to ambulatory surgical centers and smaller practices. They might benefit from a more portable model.

Budget and Maintenance

Many people find it tempting to buy the cheapest model. However, a lower price often means lower quality or missing essential features.

Think about units that cost more at first. They are likely to save you money in the long run. This is because they need repairs less often.

It would be best to consider the cost of owning an ESU, as these devices require periodic maintenance and calibration. Choose manufacturers that offer strong warranty terms and affordable maintenance plans. Also, make sure they have readily available consumables and replacement parts.

Brand Reputation and Support

Last but not least, brand reputation and customer support should be considered. A well-known brand is more likely to have a reliable supply chain. This means you can easily find replacement parts, electrodes, and accessories for your ESU. Timely technical support is also crucial for ESU, especially in the clinical setting.

Endnote

Choosing the right ESU means picking a model that fits your clinical practice and its needs. You also want to stay within your budget.

Visit Paracor Medical to buy an ESU machine. They are a trusted supplier of laboratories and offer many products that may suit your needs.