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COMPLICATIONS
Patients should be warned of the possibility of delayed bleeding and should be reassured that it can, in the vast majority of cases, be controlled by 20โ30 minutes of constant direct pressure over the wound. Trips to the local emergency room to stop postoperative bleeding are unusual but can occur. Patients should also be advised that for ablative procedures including electrocoagulation, scarring, in the form of a hypopigmented area, may occur.
Other potential hazards of electrosurgery are briefly discussed below.
Fire
There is a risk of fire or explosion if electrosurgical procedures are conducted in the presence of alcohol, oxygen, or bowel gases (methane). Care should be taken to be certain that the operative site is free of alcohol residue, i.e. confirm any alcohol-containing skin preparation has completely dried before proceeding with electrosurgery. Of note, aluminum chloride solutions used for hemostasis can contain over 90% alcohol (v/v). Oxygen is usually not a problem except in the operating room setting. Bowel gases are highly flammable! Use care in the perianal region.
Thermoelectric Burns
Although modern generators are isolated from earth, and are often equipped with sophisticated monitoring systems, current can still be diverted away from the return electrode and cause an accidental burn at the point at which it leaves the patientโs body. Alternative pathways occur when the current is diverted from the return electrode and finds an alternative path to return to the generator. When the point of contact between the patient and the grounded object is small, even a relatively low-power current can generate sufficient current density to cause a burn. Grounded objects may include metal parts of the operating table, table accessories, or ECG electrodes. This problem is reduced, but not eliminated, by the use of isolated electrosurgical units, which have little or no connection to the ground.
Microorganism Transmission
The potential exists for transmission of microorganisms either via the electrode or via smoke plume inhalation. Neither possibility has been investigated in sufficient depth to yield conclusive results. Practitioners should minimize the risk of possible electrode transmission by using disposable or sterilized electrodes. Adapters are available that allow disposable metal hypodermic needles to be used as electrodes.
Surgical Smoke
During surgical procedures using a laser or electrosurgical unit, the thermal destruction of tissue creates a smoke by-product. Research studies have confirmed that this smoke plume can contain toxic gases and vapors such as benzene, hydrogen cyanide and formaldehyde, bioaerosols, dead and live cellular material (including blood fragments), and viruses. At high concentrations, the smoke causes ocular and upper respiratory tract irritation in healthcare personnel and creates visual problems for the surgeon. The smoke has unpleasant odors and has been shown to have mutagenic potential.
Research by the National Institute for Occupational Safety and Health (NIOSH) has shown that airborne contaminants generated by these surgical devices can be effectively controlled by appropriate ventilation using a portable smoke evacuation system. Smoke evacuators contain a suction unit (vacuum pump), filter, hose, and an inlet nozzle. The smoke evacuator should have high efficiency in airborne particle reduction and should be used in accordance with the manufacturerโs recommendations to achieve maximum efficiency. A capture velocity of approximately 100โ150 feet per minute at the inlet nozzle is generally recommended. It is also important to choose a filter that is effective in collecting the contaminants. A high-efficiency particulate air (HEPA) filter or equivalent is recommended for trapping particulates. Various filtering and cleaning processes also exist which remove or inactivate airborne gases and vapors. The different filters and absorbers used in smoke evacuators require monitoring and replacement on a regular basis and are considered a possible biohazard requiring proper disposal.
The smoke evacuator hose inlet nozzle must be kept within 2 inches of the surgical site to effectively capture airborne contaminants generated by these surgical devices. The smoke evacuator should be activated at all times when airborne particles are produced during an electrosurgical procedure that generates a significant smoke plume. After each procedure, all tubing distal to the filter must be considered infectious waste and be disposed of appropriately. The filters themselves may be used for the cumulative time specified by the manufacturer before replacement.