Electrosurgery 

Updated: Jul 30, 2018
Author: William D Holmes, MD; Chief Editor: Dirk M Elston, MD 

Overview

Background

Electrosurgery is a term used to describe multiple modalities that use electricity to cause thermal destruction of tissue through dehydration, coagulation, or vaporization.[1, 2] The two types of electrosurgery most commonly used are high-frequency electrosurgery and electrocautery.

High-frequency electrosurgery refers to four different methods: electrocoagulation, electrodesiccation, electrofulguration, and electrosection. These methods involve high-frequency alternating current, which is converted to heat by resistance as it passes through the tissue.[1] The result of heat buildup within the tissue is thermal tissue damage. These modalities are commonly used for hemostasis, debulking procedures such as rhinophyma excision, and treatment of benign and malignant skin conditions ranging from acrochordons (skin tags) to basal cell carcinoma (BCC).[1]

Electrocautery is a form of direct transference of heat to tissue. Instead of passing electrical current through the tissue, the current is used to heat a handheld element, which is then applied to the tissue. This form of electrosurgery is most commonly used for hemostasis and tumor destruction when high-frequency electrosurgery is contraindicated.

Additional modalities of electrosurgery include electrolysis, which uses a chemical reaction created by direct current to damage tissue, and coblation, used for facial rejuvenation, which uses an electrical current to ionize a conduction medium such as isotonic saline. The ionized medium is then used to transmit heat to tissue.

Indications

There are multiple indications for electrosurgery (see Table 1); in many cases, electrosurgery is combined with another modality such as a scalpel, scissors, or curette. Preserving a specimen for histopathological examination and better control of the depth of destruction are the primary benefits of combination therapy.[1]

Electrodesiccation and curettage (ED&C) of BCC is likely the most common indication for electrosurgery.[1] ED&C is indicated for nodular and superficial forms of BCC. Other forms of BCC, such as micronodular, recurrent, or morpheaform BCC, should be excised with adequate margins because of the likelihood of deeper infiltration in the dermis.

Table 1. Indications for Electrosurgery* [1] (Open Table in a new window)

 

 

Electrocoagulation

Electrodessication

Electrofulguration

Electrosection

Benign

Acne keloidalis nuchae

 

 

 

X

Acrochordon

 

X

X

X

Angioma, cherry

X

X

X

 

Angioma, spider

X

 

 

 

Condyloma acuminatum

 

X

 

 

Dermatosis papulosis nigra

 

X

X

 

Molluscum contagiosum

 

X

X

 

Mucous cysts

 

X

X

 

Nevi

 

 

 

X

Oral fibromata

 

X

X

 

Papilloma

 

X

X

 

Pyogenic granuloma

X

 

 

X

Rhinophyma

 

 

 

X

Seborrheic keratosis

 

X

X

 

Sebaceous hyperplasia

X

 

 

 

Syringoma

 

X

 

 

Telangiectasia

X

 

 

 

Verruca vulgaris

 

X

 

 

Verruca plana

 

X

X

 

Premalignant

Actinic keratosis

 

X

X

 

Malignant

Squamous cell carcinoma in situ without extensive follicular involvement

 

X

X

 

Nodular BCC

 

X

X

X

Superficial BCC

 

X

X

X

*Adapted from SL Soon and CV Washington, Electrosurgery, in Robinson, et al., Surgery of the Skin, 2nd Edition. Mosby, Elsevier; 2010.[1]

Contraindications

Anatomical location and the presence of an implantable electronic device (IED) are the two main considerations when evaluating for possible contraindications to electrosurgery.

Anatomical locations of concern include sites near the eye and any site/mass with a narrow stalk or base such as the scrotum, finger, or large papilloma.[1]

Application of current at sites with a narrow stalk or base can cause a phenomenon called “channeling,” in which the current is concentrated as it passes through the narrowed region, creating the potential for tissue damage at the base.[1] Channeling may also result in distant damage if the current contacts and then travels along tissue that is more conductive than the surrounding tissue (eg, nerves or vessels). This form of channeling may result in distant coagulation with severe consequences if it occurs on a finger or the penis.[1]

Ocular injury is not a result of the channeling phenomenon; rather, it is caused by sparks or direct thermal injury and can be prevented by avoiding use of the treatment electrode near the eye or by using corneal shields.

While not an absolute contraindication to the use of electrosurgery, IEDs such as cardiac and gastric pacemakers, implantable cardioverter defibrillators (ICDs), cochlear implants, and deep brain, nerve, spinal cord or bone stimulators create unique risks. Patients with these devices require thorough preprocedure evaluation and may require intraoperative monitoring and postprocedure device assessment.[3] (See Complications.)

Technical Considerations

For a detailed discussion of the electrical principles involved in electrosurgery, including waveforms and tissue effect, circuit types, transformers, direct and alternating current, and ohmic heating, please refer to Surgery of the Skin; Procedural Dermatology, 2nd edition, Chapter 9.[1]

For technical aspects of electrocautery, electrodesiccation, electrofulguration, electrocoagulation, and electrosection, please refer to Technique.

Outcomes

The success rate of ED&C for BCC depends on the clinician’s skill using the curette. When using the curette for BCC, the tumor’s physical consistency is different from surrounding normal skin. A skilled clinician can detect subclinical extension of the tumor based on this physical consistency and obtain adequate margins beyond this subclinical border (usually 2-4 mm). Reported recurrence rates are as low as 1.6% in a prospective cohort study of 93 patients treated with ED&C at a VA hospital[4] to a range of 5.7-18.8% reported in a structured review.[5]

Complications

Electric shocks are a risk, especially when a grounding pad is not used and the current is dispersed randomly throughout the body, creating the buildup of static electricity. Shocks may be felt by the patient if there is contact with grounded objects such as nearby metal or metal on the treatment table. Shocks may also be delivered to grounded people nearby, including the practitioner. Not making or breaking contact with the patient during current application may minimize the risk.[1]

Burns may occur in the presence of flowing oxygen or when flammable cleansers such as alcohol are used. The use of nonflammable cleansers such as povidone-iodine or chlorhexidine may eliminate the risk.[6] It may also occur after the use of aluminum chloride solutions that contain alcohol.

Electrical burns may occur if a patient is in contact with a grounded object, creating a low-resistance path that concentrates the current in a small surface area. Intravenous poles, rectal temperature probes, and electrocardiography needles or plates are hazards.[1] In addition, electrical burns may result from current channeling (see Contraindications) and faulty placement of the grounding pad. Avoiding placement of the grounding pad over metal implants, scar tissue, and bony prominences, as well as ensuring good contact between the grounding pad and the skin, will minimize the risk of burns.[1]

Eye injury may result from sparks or direct thermal injury when electrosurgery is used near the orbit. Injury can be prevented by avoiding use of the treatment electrode near the eye or using corneal shields.[1]

Transmission of infection is a theoretical and real risk of treatment with electrosurgery. Bacterial and viral particles may be transferred directly or via aerosolization during treatment.[7] Precautions include the use of surgical masks and eyewear, as well as the use of a smoke evacuator with the nozzle placed within 2 cm of the operative site.[1, 7, 8, 9]

Electromagnetic interference with IEDs is a much-discussed risk of electrosurgery. Heat electrocautery is generally considered the safest form of electrosurgery in these patients, as no current passes through the body. The main risk of electrocautery is direct thermal injury to an underlying implantable device when using the instrument directly over the device.[1, 3]

The next safest form of electrosurgery is biterminal (bipolar) electrosurgery, such as electrocoagulation or electrosection. The electrical current in biterminal electrosurgery passes from one electrode through the patient to the other terminal, thus minimizing random dispersion of electrons within the body and interaction with an IED. When used properly, data suggest that biterminal electrosurgery poses no risk of device malfunction with cardiac devices.[1, 3]

Monoterminal (monopolar) electrosurgery (ie, electrofulguration and electrodesiccation) has the highest risk for electromagnetic interference (EMI) with an IED[1] because of the dispersion of the electrical current throughout the body. High-powered units found in hospital operating rooms seek to minimize this risk by using a grounding pad attached to the patient. The electrical current initiated in the unit is delivered through the single unheated electrode to the body, where it travels through the tissue to the grounding pad and then back to the unit to complete the circuit.[3]

Proper placement of the grounding pad to avoid a direct line of travel for the current from the electrode through the IED to the grounding pad may reduce but not completely eliminate the risk for electromagnetic interference. Low-power units used in outpatient settings generally do not require a grounding pad, and the current is left to disperse randomly throughout the body, increasing the risk of interference.[3]

Modern cardiac pacemakers may have more protection from EMI, at least in part, owing to efforts by manufacturers to protect the devices.[1, 3] Examples include metallic shielding, which helps protect against high-frequency interference; “bandpass filters,” which ignore signals falling outside the narrow range of cardiac depolarization frequencies; bipolar leads; and noise-sampling periods that convert the pacemaker to a fixed rate if ongoing EMI is sensed.[1, 3]

Of all patients with implantable cardiac devices, those who have no underlying rhythm (pacemaker-dependent) should be identified.[3] This special subset comprises 5%-10% of patients with implantable cardiac pacemakers.[3] Prolonged EMI could lead to symptomatic disruption of the pacemaker. Unfortunately, this status is not always known by the patient. The cardiologist or the device representative should know whether the patient is pacemaker-dependent and may place the device into an asynchronous pacing status thought to minimize the potential for disruption, although complications have still been reported.[3]

 

Periprocedural Care

Patient Education & Consent

Informed consent should take place prior to any procedure involving electrosurgery. The clinician should review the risks and benefits of the recommended electrosurgical modality, as well as alternative therapies. Most often, the informed consent is documented on a form that outlines these risks, benefits, and alternatives and that both the patient and clinician sign. Below is a sample informed consent for ED&C.

ELECTRODESICCATION AND CURETTAGE (ED&C)

This is a general summary about this procedure and does NOT list every possible benefit, risk, or adverse event ever reported about this procedure.

What is ELECTRODESICCATION AND CURETTAGE (ED&C)?

See the list below:

  • It is a surgical technique which involves sequential curettage (scraping) of a skin lesion followed by electrodesiccation (a form of electronic cautery). The sequence is generally repeated 3 or 4 times.

  • It is an alternative to more invasive surgery.

  • It is used to treat benign and superficial malignant skin lesions including but not limited to: seborrheic keratosis, actinic keratosis, nodular and superficial basal cell carcinoma, squamous cell carcinoma in-situ.

Benefits, alternatives, risks:

Benefits may include treatment of skin lesions, lower cost (compared to more invasive surgery), and rapid delivery of treatment.

Alternatives vary depending on the type of lesion being treated but may include observation, excision, topical chemotherapy, cryotherapy and curettage, and excision.

Risks include discomfort, pain, bleeding, burns, electric shock, recurrence, conversion to excision, infection, changes in pigmentation, and scar. Please contact your doctor if these or other adverse symptoms occur.

Absolute Contraindication: Implanted cardiac defibrillator

Relative Contraindications: Cardiac pacemaker, implanted deep-brain stimulator, other implantable electrical device, and bleeding disorders.

Please sign below if the following statements apply to you:

I understand the information provided to me above.

I understand that I can ask my health care provider for any additional information or clarification.

I have been given the opportunity to ask my health care provider about alternative therapies.

_____________________________________________________________________________________

Patient Parent Health Care Proxy Date Time

_____________________________________________________________________________________

Practitioner’s signature: MD, APRN, PA-C Date Time

Pre-Procedure Planning

The preprocedure workup should be focused on identifying and minimizing risks. The patient’s history should be reviewed to identify risk factors for excessive bleeding and disease conditions that may affect healing. The history and physical examination should identify patients with IEDs. Once an IED is identified, further investigation is warranted.[3]

The IED should be characterized by type, medical indication, anatomic location, date of implantation, programmability, date of last interrogation, symptoms if turned off, and need for postoperative interrogation. Depending on the complexity of the planned procedure and type of electrosurgery required, it may be necessary to contact the physician managing the device, as well as the respective industry representative.[3]

Equipment

Electrosurgical equipment is manufactured and distributed by multiple vendors. Office-based units come in a wide variety of styles, and most units have a range of optional features. The images below depict several types of electrosurgical equipment but do not represent all of the available brands or options. The authors have no affiliation with the makers of these devices and this is not intended as an endorsement.

An office-based, portable electrosurgical unit. An office-based, portable electrosurgical unit.
Electrosurgical tips: disposable blunt tip, dispos Electrosurgical tips: disposable blunt tip, disposable sharp tip, and reusable fine needle tip (front to back).
Handheld electrocautery unit with cap. Handheld electrocautery unit with cap.
Handheld electrocautery unit with activated (hot) Handheld electrocautery unit with activated (hot) tip.
An evacuator such as the one shown, may be used to An evacuator such as the one shown, may be used to safely remove electrosurgical smoke.

Patient Preparation

Patients should be instructed to remove all metal objects, including jewelry, and avoid contact with grounded metal objects during the procedure.[1] This will help minimize the risk of inadvertent shocks and electrical burns.

 

Technique

Electrocautery

Electrocautery is a form of direct transference of heat to the tissue. Instead of passing electrical current through the tissue, low-voltage, high-amperage, direct or alternating current is used to heat a handheld element, which is then applied to the tissue.[1] The resulting effect depends on the tissue; direct application to tumor leads to destruction of tumor cells, whereas application to vessels results in hemostasis. Electrocautery is most commonly used when high-frequency electrosurgery is contraindicated.

Electrodesiccation

In electrodesiccation, the unheated electrode makes contact with the skin and results in superficial dehydration due to ohmic heating.[1] The effect is mostly in the epidermis and carries a minimal risk of scarring except at higher voltages, which increase the depth of destruction and may cause superficial scarring and hypopigmentation.[1]

Electrodesiccation and Curettage

ED&C is a commonly used form of electrosurgery.[1] ED&C is indicated for nodular and superficial forms of BCC, whereas micronodular, recurrent, or morpheaform BCC should be excised with adequate margins because of the likelihood of deeper infiltration in the dermis.[5, 10]

The success rate of ED&C for BCC depends on the clinician’s skill with the curette. When using the curette for BCC, the tumor’s physical consistency differs from surrounding healthy skin. A skilled clinician can detect subclinical extension of the tumor based on this physical consistency and obtain adequate margins beyond this subclinical border (usually 2-4 mm).

Reported recurrence rates are as low as 1.6% in a prospective cohort study of 93 patients treated with ED&C at a VA hospital[4] to a range of 5.7%-18.8% reported in a structured review,[5] but this may reflect selection bias, as a higher percentage of BCCs treated with ED&C are located on the trunk.[10]

The video below depicts the ED&C technique used by the authors.

Electrodesiccation and curettage: the method employed by the authors.

Electrofulguration

Electrofulguration and electrodesiccation both use markedly damped, high-voltage, low-amperage current with a single terminal to produce local tissue destruction.[1] Electrofulguration distinguishes itself from electrodesiccation by the lack of direct contact of the unheated electrode with the skin. The result is superficial epidermal carbonization via sparks from the electrode, which is held 1-2 mm above the skin’s surface.[1] The carbonization tends to insulate the underlying tissue, minimizing deeper damage and reducing scarring.[1]

Electrocoagulation

Electrocoagulation uses an electrode, which makes contact with the skin and an indifferent electrode (grounding pad) and low-voltage, moderately damped, high-amperage current to cause deeper tissue destruction (with minimal carbonization) and hemostasis of vessels less than 1 mm.[1] To obtain hemostasis, a dry surgical field is required; the electrode may then be applied directly to the vessel or by clamping the vessel with forceps and indirectly applying the current to the vessel by touching the treatment electrode to the forceps.[1] The collagen and elastic fibers are fused, and hemostasis is achieved.[1]

Electrosection

Electrosection also uses two electrodes (treatment electrode and indifferent electrode) and low-voltage, high-amperage current.[1] The effect on tissue depends on whether the current is undamped or slightly damped. Undamped electrosection results in cutting without coagulation, whereas a slightly damped current offers some coagulation.[1] Overall, the effect is tissue vaporization with minimal peripheral heat damage.[1] A major advantage of electrosection is the ability to cut tissue while simultaneously obtaining hemostasis.[1]