Electrosurgery

Article Author:
Dana Baigrie
Article Editor:
Talel Badri
Updated:
9/11/2018 12:06:58 PM
PubMed Link:
Electrosurgery

Introduction

Electrosurgery is a technique often used in dermatologic surgery to provide superficial or deep coagulation or cutting of the skin. The skin has a poor conducting properties for the electrical flow of energy. Therefore, this energy builds up and is converted into heat. The endpoints of electrosurgery vary based on the waveform and result in either desiccation, coagulation, or sectioning of the skin.

Harvard physicist William Bovie made one of the most important contributions to electrosurgery. His device offered both coagulation and cutting currents. This was used in the 1920s by a neurosurgeon to cut through tissues and control bleeding during surgical procedures. The term “bovie” is still used to refer to an electrosurgery device or even the act of performing electrosurgery in general.

The main types of electrical hemostasis used in dermatologic practice include electrocautery, electrofulguration, electrodesiccation, and biterminal electrocoagulation. Electrolysis and electrosection are other types of electrosurgery that may be utilized in the field of dermatology.

Indications

The clinical situation will determine which mode of electrosurgery is appropriate to use. If only the epidermis needs treatment, electrodesiccation would be a good choice as it results in very little or no scarring. Electrodesiccation causes very superficial tissue damage by dehydrating the treated skin. It is a markedly damped, high-voltage current delivered by a monoterminal device. If the surgeon holds the electrode slightly away from the skin, a spark forms between the skin and the electrode. This is termed electrofulguration. This technique also creates a very superficial destruction as the carbonization on the surface insulates the underlying tissues from the spread of heat. These 2 techniques are used commonly by dermatologists. 

Common dermatologic indications for electrofulguration or electrodesiccation for a superficial skin ablation include acrochordons, actinic keratosis, small angiomas, epidermal nevus, seborrheic keratosis, verruca plana, or hemostasis for capillary bleeding.

Electrocoagulation or deep skin ablation can be used to treat angiofibromas, basal cell carcinoma, Bowen’s disease, squamous cell carcinoma, ingrown toenail matrixectomy, sebaceous hyperplasia, hemostasis from arterial bleeding, benign adnexal tumors (syringoma, trichoepithelioma), or verruca vulgaris.

Electrosection involving skin incision or excision may be employed in the treatment of acne keloidalis nuchae, blepharoplasty incision, rhinophyma repair, scar revision, shave removal (benign skin lesions), skin-flap incisions and undermining, and resurfacing. This technique is used for quick and effortless excisions or incisions. The major advantage of electrosection over surgery with a scalpel is the rapid hemostasis that is provided at the time of incision. However, a smoke-plume will be generated with this technique and produces both safety hazards and an unpleasant smell for the patient.

Contraindications

Though not an absolute contraindication, electrosurgery in patients with cardiac pacemakers or implantable cardiac defibrillator (ICD) devices is a topic of much debate. The flow of electrical energy during electrosurgery can interfere with the functioning of these devices. This can lead to skipped beats, firing of a defibrillator, bradycardia, asystole, or reprogramming of a pacemaker. While most modern implantable devices are resistant to external electromagnetic signals, the theoretical risk of interference still exists. 

For patients with these cardiac devices, it is recommended that the surgeon use short bursts of energy of fewer than 5 seconds, lower the power settings, avoid cutting current usage, and avoid treated the area around the cardiac device. The risk also decreases by confining the current to a very small area, for example with the use of bipolar forceps. In the dermatology practice, there have been no reported cases of interference with a pacemaker or ICD. 

To virtually eliminate the risk in high-risk cardiac patients, the surgeon should use true electrocautery. This has potential to cause more tissue damage compared to electrosurgery, but there is no current flowing to cause interference in these patients. Magnets are also commonly used during electrosurgery to reduce the risk of with implantable devices. A magnet, when placed over the device, will cause the pacer to stop paying attention to all electrical signals and pace at a reset rate.

Equipment

The equipment necessary for electrosurgery includes the electrosurgical device itself, as well as sterile sleeves to place over the handle and disposable electrode tips. A smoke evacuator is an essential tool when performing electrosurgery, as it safely removes the smoke plume which has been proven to be mutagenic. 

Personnel

The personnel needed to operate an electrosurgical device include an operator trained to use the device and their surgical assistants. 

Preparation

In preparation for an electrosurgical procedure, the surrounding skin should be cleansed with an antiseptic agent such as chlorhexidine or povidone iodine. Alcohol should be avoided or allowed to dry completely as can it may ignite with electrosurgery. Local anesthetics should also be administered prior to electrosurgery, with few exceptions such as treatment of small facial telangiectasias. A nerve block may be a better option for a rhinophyma repair or more extensive procedures. 

The operator should ensure sterile sleeves are placed over the wand handle, and new disposable electrode tips should be utilized. Eye protection, gloves, and masks should be worn by both the operator and the surgical assistants to prevent exposure to smoke-borne organisms or potential mutagens. Smoke evacuation should be ready to remove this smoke plume with electrosection procedures. Smoke evacuators with a high-efficiency particulate air filter and a capture velocity of approximately 100 to 150 feet per minute are recommended. It should be held within 2 inches of the surgical site to collect the airborne contaminants. 

The operator should determine the proper settings for the particular procedure prior to starting the case.

Technique

Electrocautery, invented in 1875, was the forerunner or electrosurgery. Electrocautery and electrosurgery are often incorrectly used interchangeably. Unlike electrosurgery, which is alternating current, electrocautery involves direct current through a metal wire that resists to the flow of energy. With this technique, a surgeon can achieve hemostasis in a wet surgical field. However, the damage to tissues may impair wound healing. Electrocautery is typically reserved for patients with pacemakers or defibrillators because there is no current flowing through the patient to compromise the device’s functioning.

In 1907, Walter de Keating-Hart and Pozzi introduced “fulguration,” which in Latin means "lightning." They postulated the that this superficial carbonization which generated heat without directly applying the electrode to the skin was ideal to treat the skin, as it could selectively destroy tumor cells by disrupting their nutritional supply. In 1911, William Clark introduced “desiccation,” which in Latin means “to dry out.” This technique dehydrated the tissue with fine sparks of energy versus the thicker sparks of electrofulguration. 

Electrodesiccation and electrofulguration are used for very superficial skin lesions in a monoterminal fashion. The main difference is electrodesiccation generates a high-voltage spark which causes dehydration of the treated tissue site via direct contact with the tissue. Electrofulguration is held at a small distance from the tissue achieving superficial destruction secondary to surface carbonization. This carbonization protects the underlying tissues from the spreading of thermal heat. This electric current does not penetrate deeply, so it will not seal nearby blood vessels.

Electrocoagulation was later introduced in 1909 by Doyen as a different “recycling” technique in which the electrode touched the tissue directly, while an indifferent electrode removed the electricity and flowed back into the device. He claimed this was more effective in tumor cell destructions.

Electrocoagulation produces a moderately damped current in a biterminal manner which is higher amerage and lower voltage than electrodesiccation and electrofulguration. Electrocoagulation penetrates deeper than the electrodesiccation/fulguration, therefore greater damage to tissues occurs. Monopolar or bipolar methods can achieve hemostasis by this electrocoagulation. A monopolar method of hemostasis includes briefly touching the bleeding vessel directly, or by touching the electrode to forceps or a hemostat on the clamped vessel. Bipolar electrocoagulation occurs with bipolar forceps are applied directly to the bleeding vessel. Because the energy from the electocoagulation device can travel several millimeters along the vessel, short bursts of energy and minimum power setting are strongly encouraged to prevent delayed bleeding.

The biterminal application of a damped, low-voltage and high amperage current produces minimal tissue damage and lateral heat spread. Unlike other modalities of electrosurgery, it provides hemostasis simultaneously while cutting. A pure cutting method is executed by using an undamped tube current. This will cause vaporization of tissue with no hemostasis. A variety of electrodes may be used depending on the desired effect, with the most common a straight, narrow electrode to incise skin. This is employed in a swift, continuous stroke-like motion. Since it is slightly damped current, there will be some charring present at the excised tissue margins.

Complications

The main complications to consider when treating a patient with electrosurgery are the possibility of delayed bleeding and scarring with hypopigmentation. Patients can be reassured that delayed bleeding can be controlled with 20 minutes of constant direct pressure over the wound. 

Other potential complications of electrosurgery include fire, thermoelectric burns, infectious transmission from the electrode, or smoke plume inhalation. Fire risk is greatest in the presence of alcohol, oxygen, or bowel gases. Aluminum chloride used commonly in hemostasis may contain 90% alcohol; therefore, clinicians must be sure the surgery site has dried completely before using electrosurgery. Also, care should be taken when using electrosurgical devices in the perianal area due to highly flammable bowel methane gas.

Research studies have confirmed surgical smoke by-products contain toxic gases and vapors including benzene, cyanide, cellular material, and viruses. These contaminants can be controlled by using smoke evacuators. 

Clinical Significance

Electrosurgery is used quite frequently in dermatologic procedures, whether it be for removal of benign or malignant neoplasms or cosmetic indications such as acne keloidalis nuchae or dermatosis papulosa nigricans removal. Electrodesiccation and curettage are also used very commonly in dermatology clinics for treatment of superficial skin cancers such as a squamous cell in situ or basal cell carcinoma. It is important to understand the difference in these modalities to employ the correct surgery technique for best patient outcomes.