14 Electrosurgery

Richard P. Usatine, MD, and John L. Pfenninger, MD

Electrosurgery is used in dermatologic practice to destroy benign and malignant lesions, to control bleeding, and to cut or excise tissue. Many types of electrosurgical units are available for use in the office setting. Modern high-frequency electrosurgery units transfer current to the patient through “cold” electrodes. The water molecules are energized to the point that cells literally vaporize as opposed to being burned. The term electrocautery implies that heat is transferred directly to tissue with a heated electrode; electrocautery is just one type of electrosurgery. The battery-powered units that produce a red wire when activated are an example of a simple cautery unit and are useful for draining a subungual hematoma and other minor procedures such as cauterizing the lumens of resected vas deferens where residual tissue damage is not an issue.

The major electrosurgical functions include fulguration, electrodesiccation, electrocoagulation, and electrosection (cutting). In fulguration, the electrode is held away from the skin so that there is a sparking to the surface (such as happens with lightning). In fact, the term fulguration comes from the Latin term fulgur, which means “lightning.” Fulguration produces a high-intensity but more shallow level of tissue destruction (Figure 14-1). With electrodesiccation, the active electrode touches or is inserted into skin to produce deeper tissue destruction (Figure 14-2). Epilation is a type of desiccation in which a fine-wire electrode is inserted into a hair follicle to literally “cook it.” Electrocoagulation is used to stop bleeding in deep and superficial surgery (Figure 14-3). In electrosection, the unit is set so the electrode cuts tissue (Figure 14-4). The higher the unit’s operating electrical frequency (not to be confused with power), the less tissue damage is left behind when using the cutting function.

FIGURE 14-1 In fulguration, the electrode is held away from the skin so that there is a sparking to the surface (such as happens with fulgur, “lightning”). Fulguration produces a high intensity but more shallow level of tissue destruction that may reach the upper dermis.

(Adapted from Sebben JE. Electrosurgery. In Ratz JL, ed., Textbook of Dermatologic Surgery. Philadelphia: Lippincott-Raven; 1998.)

FIGURE 14-2 With electrodesiccation, the active electrode touches or is inserted into the skin to produce tissue destruction deeper into the dermis.

(Adapted from Sebben JE. Electrosurgery. In Ratz JL, ed., Textbook of Dermatologic Surgery. Philadelphia: Lippincott-Raven; 1998.)

FIGURE 14-3 (A) Electrocoagulation is used to stop bleeding in deep and superficial surgery. In this image an indifferent electrode is being used to produce deeper tissue coagulation. Electrocoagulation can also be performed without an indifferent electrode. (B) Electrocoagulation is being performed in the undermined area of an ellipse using a Hyfrecator while the surgical assistant holds up the tissue with skin hooks.

(A: Adapted from Sebben JE. Electrosurgery. In Ratz JL, ed., Textbook of Dermatologic Surgery. Philadelphia: Lippincott-Raven; 1998.)

FIGURE 14-4 (A) In electrosection, the unit is set so the electrode cuts tissue. This mode requires an indifferent electrode. (B) Electrosection is being performed with a very tip electrode attached to a Surgitron. An indifferent electrode is placed under the patient near the surgical site.

(A: From Vidimos A, Ammirati C, Poblete-Lopez C. Dermatologic Surgery. London: Saunders; 2008.)

Current can be applied either in a unipolar or bipolar fashion. The majority of electrosurgical units (ESUs) are unipolar. Unipolar refers to the fact that the current enters a site at the point of the electrode and passes through the body to a grounding plate to complete the circuit. With bipolar applications, the current travels from one point of the electrode, through the tissue, to another point of the electrode (e.g., with fine forceps, from point to point). No grounding plate is needed for this type of use. This reduces possible complications from burns at unwanted sites where the current can exit. It also reduces complications with pacemakers. The bipolar units are ideal to control bleeding since forceps can pinpoint and grasp a bleeder. When the current is applied, only the tissue between the tips of the forceps is affected (Figure 14-5).

FIGURE 14-5 (A) Selection of bipolar forceps that could be used on a number of electrosurgical units. (B) Bipolar forceps in action for electrocoagulation while doing an elliptical biopsy. Note that a small gap is preserved between the ends of the bipolar forceps around the bleeding site. Clamping the forceps close together is not an effective method of electrocoagulation.

With dual-frequency (DF) ESUs, 1.7 MHz (1.7 million cps) is used in the bipolar function, which is better for coagulation because of the lower frequency, whereas unipolar functions (cut, blend) are at 4.0 MHz to decrease tissue damage in the cutting functions.

Electrosurgery Versus Cryosurgery

Cryosurgery is often the treatment of choice for seborrheic and actinic keratoses as well as simple warts. It is faster and easier to perform than electrosurgery for these indications because it does not require anesthesia. Cryosurgery also tends to cause less scarring than electrosurgery especially if the lesions are very superficial. However, cryosurgery may be more likely to cause hypopigmentation because the cold destroys melanocytes. This is especially important in a more darkly pigmented person. Electrosurgery can be more effective than cryosurgery for extensive condyloma, especially if a cutting current can be used.

There may be a risk of developing human papilloma virus (HPV) in the respiratory tract from inhaling the plume (smoke) from an HPV lesion as it is being treated.¹^–³ Intact HPV DNA has been isolated from the plume of verrucae that were treated with electrosurgery and lasers. Therefore, it is prudent for all physicians to use a smoke evacuator while performing laser and electrosurgical treatment of verrucae and other viral lesions. (See Safety Measures with Electrosurgery, p. 167.) Unfortunately, evidence is insufficient to measure the magnitude of these risks. These personal risks, however, may be one factor used to determine the physician’s choice of therapy for viral lesions.

One disadvantage of cryotherapy over electrosurgery is that with cryosurgery the final result cannot be seen immediately, and there is more subjective judgment involved in performing the treatment. However, the degree of damage can be estimated accurately with more experience and by following certain guidelines (see Chapter 15). Cryosurgery also causes more postoperative swelling, which may be uncomfortable for the patient but is only a transient phenomenon.

Electrosurgery Versus Scalpel

The traditional instruments for performing excisions and shave biopsies are the scalpel and razor blade. These are inexpensive, the blades are disposable, and the cuts are clean. The cold steel blades cause no heat-induced tissue damage that could obscure the pathology specimen. Using electrosurgery in place of a blade has the advantage of facilitating hemostasis while cutting. However, the lateral heat produced by the electrosurgical instrument can cause residual tissue damage that might result in slow healing as well as artifact on the edges of the biopsy specimen. The higher the frequency, the less residual damage on both the specimen removed and on the viable tissue remaining. Also, the cutting is very quick and it may go more deeply than desired, excising excessive amounts of tissue or damaging deeper nerves and vessels.

High-frequency electrosurgery on the pure cutting current will approach but not match the scalpel for producing an entirely burn artifact–free pathologic specimen. Therefore, if a malignancy (especially melanoma) is suspected, unless wide margins are being obtained, it may be best to obtain a biopsy with the scalpel (cold steel).

For excising benign lesions, the small amount of lateral heat may not interfere with wound healing when used carefully on a low-power cutting setting. A shave excision using a blade followed by electrosurgery with a loop electrode can lead to a nearly scar-free result and combines the best of both techniques to optimize the results. The mode can be set for either cutting/coagulation (blend) or preferably pure cutting only. Ideally then, the lesion (commonly a nevus or seborrheic keratosis) is shaved off with a blade and then the loop of the radio-frequency (RF) unit removes the residual tissue and controls any bleeding. If the loop will be used to perform the shave, the less the coagulation function will be used and, hence, the less damage that will result to the remaining tissue and to the biopsy specimen. Pure cutting will work just fine to make a smooth cut and control bleeding.

The Ellman Surgitron models are a high-frequency units (often termed a radio-frequency unit because it operates at 4.0 MHz, which is in the range of a radio). They employ a Vari-Tip fine-wire electrode that is adjustable in length for cutting through the skin for elliptical and other full-thickness excisions. On the pure cutting setting, the Vari-Tip electrode can cut with less lateral heat and can allow the physician to do quick and bloodless excision of benign lesions. A combined cold steel (blade) and electrosurgical procedure can also be used here. While the scalpel cuts through the skin to provide better depth control, deeper dissection/undermining and excision with cutting or blended cutting and coagulation can control bleeding.

In summary, no instrument can beat the scalpel (or razor blade) for cost and minimization of tissue damage. The high-frequency electrosurgery unit is more expensive to purchase and operate. A radiosurgery unit can be used to perform several kinds of surgery that have been traditionally performed with a scalpel. This may be beneficial if the lesion is benign and very vascular. However, with small biopsies it cannot match the scalpel for quality of pathologic specimen. Superior cosmetic results can be obtained when using the scalpel for a shave excision followed by light “brushing” of the RF loop over the base of the lesion on a pure cutting setting to smooth out any irregularities while at the same time controlling bleeding. This also tends to treat any sparse residual cells of the lesion that may persist.

Electrosurgery Versus Laser

Laser is an acronym for light amplified by stimulated emission of radiation. Laser technology uses focused light energy to affect cells. Many types of lasers are available to perform different functions (see Chapters 26 through 30). Electrosurgery is less expensive than laser surgery but is more limited in utility. The standard electrosurgical units are a fraction of the cost of a laser (as low as $1000 to 4000 compared to laser units costing $30,000 to $200,000). Most physicians face the choice of referring a patient for laser surgery versus doing electrosurgery in their own office. As with electrosurgery, the CO₂ laser may be used to cut, coagulate, and ablate (destroy) tissue. It is most often used in the office for resurfacing procedures, such as in the treatment of rhytids (wrinkles) and skin surface irregularities; pigmentation; and small vessels. The pulsed dye laser or a similar yellow-light laser is unequivocally better than electrosurgery for treating large hemangiomas and maximizing the cosmetic result. These lasers are used very effectively to treat port-wine hemangiomas. Visible-light lasers obtain better cosmetic results when treating most other vascular lesions, such as angiomas and telangiectasias. They offer much less chance of scarring.

If high-frequency ESUs are used, the radio waves vaporize cells with much the same effect as light energy from lasers. In both cases, minimal tissue damage occurs since vaporization is accomplished using either light or radiowave energy. If cell destruction is desired (such as with the treatment of a basal cell carcinoma or verrucae) then there really is no benefit to either laser or radio-frequency compared to simpler units.

In some cases, it may be appropriate to allow the patient to choose between being treated with electrosurgery or laser treatment. It is helpful to inform the patient of the risks and benefits of the two. Ultimately, the patient needs to make the final decision (especially if the goal of therapy is purely cosmetic). Although different lasers offer more options for treatment, for the majority of conditions seen in the office, electrosurgery will be more than adequate.

Equipment

Thermal Pencil/Battery Cautery

An inexpensive thermal “pencil” cautery (Figure 14-6) is a useful device to have for small skin lesions. They are also used to occlude the cut ends of the vasa when doing a vasectomy. This disposable device consists of two penlight batteries in a housing connected to a wire filament that heats up when activated. Reusable models are also available with disposable tips. These battery cautery units can be a useful tool for treatment around the eyes and on patients with pacemakers. The devices come in high- and low-temperature varieties; low-temperature devices are preferred in skin surgery.

FIGURE 14-6 Note the red-hot tip of this handheld disposable electrocautery unit. This unit performs true hot electrocautery.

Thermal pencil cautery units are also excellent for opening a subungual hematoma. When the hot electrode perforates the nail, the heated tip is cooled by the blood from the hematoma, preventing damage to the nail bed.

Electrosurgical Units

Basic Electrosurgical Units (Noncutting, Lower Frequency)

• Aaron 940 (Bovie)

• Electricator (Delasco)

• Hyfrecator 2000 (ConMed) (Figure 14-7)

• SurgiStat II (Valleylab).

High-Frequency Units (up to 4 MHz)

• Aaron 950 (Aaron) (Figure 14-8)

• Cameron-Miller (various models)

• Finesse (Utah Medical)

• Force FX (Valleylab)

• LEEP (CooperSurgical)

• Quantum 2000 (Wallach Surgical)

• Surgitron FFPF EMC (Ellman)—unipolar only

• System 2450 (ConMed).

Dual-Frequency Units (Unipolar 4 MHz and Bipolar 1.7 MHz)

• Surgitron AcuSect (Ellman)—unipolar and bipolar (Figure 14-9A)

• Surgitron Dual RF (Ellman) (Figure 14-9B)

• Surgitron Dual RF S5 (Ellman) with built-in cooling system and more robust transistors and transformers for procedures that take longer such as skin tightening [Pellevé]).

FIGURE 14-7 The Hyfrecator 2000 from the ConMed Corporation is a commonly used electrosurgical unit in the office.

FIGURE 14-8 The Aaron 950 by Bovie is an electrosurgical unit that can be used for cutting, bipolar, and the other typical electrosurgical applications.

FIGURE 14-9 (A) The Ellman AcuSect is a new combined monopolar and bipolar unit that performs cutting with a reusable neutral electrode. (B) The Ellman Surgitron dual radio-frequency unit is powerful enough to use in the operating room but may also serve as an in-office all-purpose electrosurgical unit. It can perform all modes of electrosurgery discussed in this chapter.

Some RF units were primarily developed for dermatologic applications, whereas others were introduced when the large loop electrical excision procedure (LEEP) became available for cervical conizations. All units can be used for either purpose if the proper electrodes are available. Be mindful, however, that the goal for most skin procedures is to limit scarring. The higher the operating frequency of the unit, the less tissue damage that will result. For destructive procedures, frequency is of less concern.

Because the Hyfrecator and Surgitron are commonly used in the office setting, information provided here will be specific to these two instruments but it can be readily adapted to others. This is not meant as an endorsement of these units. However, their features will be used to provide practical advice for performing electrosurgery,

With many units, accessories are disposable, including grounding pads and standard handpieces. This adds a cost of $10 to $20 per procedure just for tips in addition to increasing waste. If a new grounding pad and handpiece must be used with each patient, the costs can approach $80 to $90 per procedure (e.g., when doing the LEEP procedure). When purchasing an ESU, consider whether reusable equipment is available.

Basic units will only be able to coagulate and fulgurate. To perform modern electrosurgery, units should be capable of pure cutting current, pure coagulation, or a mix of these two (“blend,” “cut and coag”) in addition to fulguration. “Pure cutting” will still have some coagulation function (e.g., Surgitron is 90% cutting with 10% coagulation). The more coagulation, the more tissue destruction. Higher end units are more versatile and digital settings allow the user to customize the cutting and coagulation percentages in the blend setting.

Comparison of Types of Electrosurgical Units

Radiosurgery is electrosurgery using an RF current in the electromagnetic spectrum of the AM radio. Radiosurgery is performed at a much higher frequency than that used by the other basic electrosurgery units (including the Hyfrecator). Radiosurgical units are more than three times the cost of basic ESUs, but are more versatile (especially for cutting).

True radiosurgery uses an “antenna” as the neutral or indifferent electrode. This replaces the grounding plate. This antenna does not have to make contact with the skin. When using a basic ESU, a neutral electrode is not needed. Some units incorporate safety features that will not allow the unit to operate if the patient is not grounded.

The major significant difference between radiosurgery units and a basic ESU is that the radiosurgery units allow for a cutting mode. If radiosurgery is used only for hemostasis and tissue destruction of benign and malignant lesions, there may be no real difference in outcomes between them.

Accessories

Ellman Surgitron Units

• Nondisposable (autoclavable) and disposable electrodes (loops, ball, Vari-Tip) (Figure 14-12)

• LEEP electrodes (Figure 14-13)

• Nondisposable bipolar forceps (Figure 14-5)

• Control handpiece—sterile and those made to be autoclaved (Figure 14-14)

• Neutral plate (Figure 14-15).

FIGURE 14-12 An assortment of medical electrodes for single use may be purchased from Ellman for use with the Surgitron.

FIGURE 14-13 Reusable LEEP electrodes for the Ellman Surgitron or other cutting units. The handles on these are long and sturdy for intravaginal use. However, these electrodes can also be used for the treatment of rhinophyma.

FIGURE 14-14 Reusable sterilizable hand switch for the Surgitron. Note the three buttons for cutting, cutting and coagulation blend, and hemo for pure coagulation.

FIGURE 14-15 The reusable indifferent or neutral electrode for the Surgitron. This does not need to touch the skin of the patient as it works to receive radio-frequency waves.

Note that the bipolar forceps are essentially the same for both instruments. These are especially useful for coagulation of small bleeding vessels because grasping the vessel and coagulation are done in one movement. Bipolar electrosurgery can be used in a bloody field and is safer than unipolar electrosurgery for patients with pacemakers.

Units can be activated using either a hand switch or foot controls. It is a matter of preference, but the clinician may have slightly better control of the handpiece for delicate procedures when foot switches are used for activation.

Smoke Evacuators

Electrosurgery creates a plume (smoke) with a putrid smell. The smoke itself has been shown to include HPV and HIV particles although it is not known if they are infectious. It is best to use some type of smoke evacuator to remove the plume created by the surgery, especially if extensive removal/destruction is being performed. When constructing or remodeling an office, consider installing an exhaust fan (a typical bathroom fan works) to help remove the smell. Types of smoke evacuators include:

• Acu-Evac II 220 (Acuderm)

• Aaron Medical Smoke Shark (Bovie)

• Buffalo Filter

• AER Defense (ConMed) (Figure 14-16)

• OptiMumm (for use with Valleylab units)

• SaftEvac—60 to 65 dB at 1 meter (Delasco)

• Surg-e-Vac (Ellman).

FIGURE 14-16 An example of a smoke evacuator. This one is an AER Defense by ConMed.

Indications for Use of Electrosurgery

• Excising tissue

• Vaporization of tissue fragments

• Controlling bleeding (coagulation)

• Destruction of tissue

• Cosmetic functions (skin tightening)

• Nail matrixectomy

• Epilation.

One of the most common uses of high-frequency electrosurgery is the cutting current that is used to smooth out the skin at the site of a shave removal that has been performed with a blade. After removing a nevus, bleeding often occurs and an irregular surface remains. The blood makes it difficult to see the tissue. Using a large skin loop at pure cutting (level 2 or 15 to 20 W) and using a light “brushing” technique, the residual base of tissue is not only smoothed out but bleeding is controlled. Any small residual lesion can be vaporized. This all affords an excellent cosmetic result. Although the removal can be performed using the loop itself (i.e., no blade is used first), two potential problems can arise: (1) it cuts so quickly it easily goes too deep and (2) the tissue sent to the pathologist will have very minimal but definite “burn artifact,” which can make interpretation difficult. If the power is set too high, the tissue can also be totally destroyed precluding any pathologic examination. For pure destruction of lesions, there is again no advantage to the high-frequency units.

Contraindications

There are really no absolute contraindications to using electrosurgery but there are some precautions relative to contraindications:

• Pacemakers (see Pacemaker Problems, p. 168).

• Electrosurgery/cautery is not indicated as a treatment modality or for obtaining a biopsy of pigmented lesions suspicious for dysplasia or melanoma.

• Electrodesiccation and curettage (ED&C) should generally be avoided in the following circumstances:

• Aggressive (morpheaform, sclerotic), large (greater than 1 cm), or recurrent basal cell carcinoma (BCC).

• BCC larger than 2 cm will have a higher recurrence rate with ED&C (see Chapter 34, Diagnosis and Treatment of Malignant and Premalignant Lesions).

• Squamous cell carcinoma (SCC) greater than 7 to 8 mm. Excise to be sure of complete removal because SCCs are more aggressive than BCCs by their very nature.

• Immune-suppressed patients, especially those who have had organ transplants, may be best served by excising the lesions to ensure complete removal in all but the smaller lesions (less than 7 to 8 mm).

• Patients with slow healing (diabetes, peripheral vascular disease) may do better with excisional rather than destructive methods.

Location is also an important consideration when using destructive techniques for nonmelanoma skin cancers (NMSCs). Higher recurrence rates are associated with NMSC in the following areas:

• Alar groove, preauricular and periocular.

• H-zone on the face. Associated with higher recurrence rates for recurrent BCC treated with surgery rather than Mohs surgery (see Chapter 37). This was not true for primary BCC in these regions treated with surgical excision. ED&C may be performed in the H-zone as long as the patient understands that there may be a higher recurrence rate than with surgery.⁴

• SCC on non–sun-exposed skin and mucous membranes such as the lip and eyelid margins (may also be more aggressive biologically).

Electrosurgical Techniques: General Principles

Power Setting

Every electrosurgical unit is different, and the desired setting will vary for each model, procedure, lesion, or patient. Even two supposedly identical electrosurgical models may require different settings. Therefore, the setting levels provided are only starting points (Tables 14-1 to 14-3 and Box 14-1). The basic principle for setting the correct power output is to start low and increase the power until the desired outcome (destruction, coagulation, or cutting) is achieved. For ablation/destruction, the tissue should bubble or turn gray. Keep in mind that destruction of tissue below the visible area of treatment can occur. The power setting for coagulation is generally higher than the setting needed for tissue destruction. A rule of thumb is to use the lowest power setting that accomplishes a given result so as to achieve cosmetically acceptable outcomes. It helps to moisten the tissue to provide better contact and allow a lower power setting.

TABLE 14-1 Range of Power Settings with the Hyfrecator 2000

Lesions	Power Setting (watts on low)	Type of Electrode
Benign
Angiomas (cherry)	2–2.5	Sharp or dull
Angiomas (spider)	2–2.5	Sharp or needle
Condyloma acuminata	12–18	Dull
Dermatosis papulosa nigra	2–2.5	Dull or sharp
Pyogenic granulomas	16–20 or switch to high	Dull
Sebaceous hyperplasia	2–2.5	Dull
Seborrheic keratosis	10–14	Dull
Skin tags (acrochordons)	2–2.5	Sharp
Syringomas	2–2.5	Sharp
Telangiectasias	2–2.5	Sharp or needle
Verrucae vulgaris	12–18	Dull
Verrucae plana	12–18	Sharp or dull
Malignant
Basal cell carcinoma	16–20	Dull
Squamous cell carcinoma	16–20	Dull

Disclaimer: Every patient and every electrosurgical unit is different. These numbers are just suggestions and each clinician must find the best settings based on experience with their patients and unit.