Education in Electrosurgery Technology is Key for Patient Safety
By Kelly M. Pyrek
It is estimated that more than 3 million laparoscopic surgical procedures are performed annually in the United States, with approximately 85 percent of surgeons using electrosurgical instruments in these procedures.1 The ubiquitous nature of these procedures has the members of many endoscopic suites paying particular attention to reducing the risk of inflicting thermal burns to patients during minimally invasive surgeries. While minimally invasive surgery technology is revolutionizing healthcare -- reflected in the tremendous advances made in science -- it may exact a greater price for the benefits it yields. These burns can cause patient injury, serious post-operative complications, even death.
These burns are often caused by faulty equipment, such as electrical generators and electrodes, or by incorrect usage by healthcare workers (HCWs). Unintended tissue damage can result from stray electrosurgical burns caused by insulation failure and capacitive coupling during laparoscopy. An elemental understanding of electricity is key to avoiding burns. Since electrical current flows toward the ground and it follows the path of least resistance, it stands to reason that monopolar electrosurgery creates a complete electrical circuit from the active electrode to the targeted tissue, to the dispersive return electrode, and back to the generator.2
George Vilos, MD, professor of obstetrics and gynecology and the director of endoscopic surgery at the University of Western Ontario in Canada, writes, "Because surgeons now work through keyhole incisions and manipulate electrodes and instruments through long, narrow channels, it is more difficult than ever to prevent the electricity from traveling outside this path and burning or vaporizing nontargeted tissue."3
Many burns during electrosurgery can be traced to direct coupling between surgical instruments, insulation failure and capacitive coupling. Insulation failure can occur when the insulation along the shaft of the active electrode breaks down and electrical currents "leak" from the instrument and burn nearby tissue. Causes of insulation defects can range from normal wear and tear, to contact with sharp instruments such as trocar cannula, to stress placed on the electrode from high voltages. Capacitive coupling occurs when electrical current is induced from the active electrode to nearby conductive material through intact insulation. In electrosurgery, the charge on the active electrode switches from positive to negative at a very high frequency. The varying electrical field around the active electrode can transfer high levels of electrical current to nontargeted tissue and cause burns.
Voltage can affect the performance of the electrosurgical electrode, since the higher the peak voltage, the greater the chance for capacitive discharge through the electrode insulation or the radio frequency cable. For this reason, more than two decades ago the American Association of Gynecological Laparoscopists (AAGL) developed voluntary standards to prevent patient injuries. Within these standards, which were published in the Federal Register Feb. 26, 1980, is the recommendation that unipolar output power be limited to 1,200 volts and 100 watts at maximum generator output.4 According to surgical instrument manufacturer Richard Wolf, the maximum output power of the electrosurgery unit must be matched to the surgical application. For gastroenterology, gynecology and rhinolaryngology procedures, the company recommends unipolar output power should not exceed 120 watts and units with incorporated coagulation current source for blended current, 170 watts.5 Electrosurgical generators operate between 500,000 cycles per second (500 KHz) and 3 million cycles per second (3 MHz), with the capacitive effect greater at 3 MHz. Therefore, generators that operate at these extremely high frequencies will be subject to more RF-current leakage through insulated instruments, cables and cannulae, meaning a more probable opportunity for injuries.
While technology and gadgetry can lend an air of heightened patient and HCW safety, there is increased need for caution. "More important than flashy meters is the realization that surgery during the last decade has become enormously sophisticated," Hausner says. "Therefore, a specially designed electrosurgical unit should be utilized for surgical procedures such as endoscopic polypectomy and laparoscopic procedures. The surgeon who has been using electrosurgical equipment empirically for a long time must retrain on the selection and use of electrosurgical equipment for laparoscopy."
Didactic education is imperative, say Michelle Carpenter, BSN, RN, CGRN, hospital supervisor at St. Joseph's/Candler Health, and Lisa Miller, LPN, CGN, staff nurse with Gastroenterology Consultants of Savannah (Ga.). They say it's never too elemental for endoscopy team members and risk managers to review the basics. "Electrosurgery is the basic component for anything that's done therapeutic in an endoscopy suite," Miller says. "There are monopolar and bipolar generators, and HCWs must understand the whole process as well as the mechanics of the units -- especially the older models because there are no safety mechanisms in place. If you have a pad misplaced, the older ones will still fire; the newer models won't fire if you don't have everything hooked up properly. A lot of the education about current flow really needs to come from reading the unit's manual, and HCWs need to know the individual machine; however, they also need the didactic education of learning from peers and educators."
With so many older electrosurgery generators and instruments circulating in hospitals, Miller and Carpenter emphasize that HCWs need to be familiar with the features of older and newer models, and be able to adjust surgical prepping and procedure accordingly.
"The newer models have safety features that prevent firing if the pad is misplaced, or if the cord is not hooked up to the machine properly," Miller says. "The older models will fire and you will get burned. A lot of hospitals have both older and newer models, so that's when you really have to pay attention to the unit and know what you are using. There's so much science involved with electrosurgery. In our education process, we start with the background, such as what a generator is, how electrodes work and what the source of radio frequency energy is and how it works."
"Electrosurgery and endoscopy are booming but it's challenging to find the time to provide up-to-the-minute education," Carpenter says. "It really takes a manager or a director to say, 'We're going to have this orientation process in place and we're going to make sure HCWs meet all of these competencies in electrosurgery technology before we put them out on the floor.' I think there are sufficient opportunities for endoscopy suite members to get educated."
With regard to formal best practices protocol for electrosurgery, Carpenter says there's very little that specifically addresses patient safety. She adds, "Safety is a big thing with Joint Commission on Accreditation of Healthcare Organizations (JCAHO), and it's up to individual endoscopy teams and their hospitals to examine their clinical practices carefully." Carpenter and Miller emphasize that there's no such thing as too much education when it comes to ever-changing technology.
"Education is critical," Miller says. "HCWs must be familiar with whatever equipment and instruments they are using because they are not all the same. The difference between cut and coagulation is big because everyone gets confused on that concept. Even the physicians ask, 'What happens if I turn this (dial) up... does that mean I have more cut or more coagulation?'"
"To really be sure that the insulation is not compromised, I recommend implementing an electrosurgical unit that employs active electrode monitoring technology, which virtually eliminates these type of electrical burns," Vilos says. "AEM encases the insulated electrode in a protective metal shield that is connected to the generator; the entire probe also is covered with an extra layer of insulation. The extra conductive and insulating layers ensure that stray current is contained and flows right back to the generator. The system monitors the electrical circuit so if stray energy reaches dangerous levels, the unit shuts off automatically and sounds an alarm before a burn can occur. This is presently considered the standard of care in endoscopic electrosurgery."6
Manufacturers of electrosurgical products using AEM technology say it requires no change in clinical practice or surgical technique. Other manufacturers are turning to argon-enhanced electrosurgery that introduces a new element of precision and control in electrosurgical applications. The clinical benefits demonstrated by argon-enhanced coagulation include quick and efficient coagulation; a thinner, more flexible eschar; less charring; and less tissue damage.
Carpenter and Miller say HCWs should take several factors into consideration when evaluating electrosurgery products. "Criteria for selecting a brand will differ from hospital to hospital, but we recommend endoscopy team leaders consider what kind of patients they see to determine product needs," Carpenter says. "They also should consider the total number of electrosurgery procedures performed, which will dictate what kind of equipment is needed, for instance We do 1,400 to 1,600 procedures a month. They also should think about how many physicians use the facility and the age of their instruments."