MODULE 5 Electrosurgery RPN 2023.pdf

MODULE 5: Electrosurgery Suggested Readings Alexander’s Care of the Patient in Surgery (2022) p. 220 - 225 ORNAC Standards 2023 p. 3-141 - 153 www.medtronic.com/covidien/products/vessel-sealing/...

MODULE 5: Electrosurgery Suggested Readings Alexander’s Care of the Patient in Surgery (2022) p. 220 - 225 ORNAC Standards 2023 p. 3-141 - 153 www.medtronic.com/covidien/products/vessel-sealing/ ligasure-retractable-l-hook www.medtronic.com/covidien/ Learning Outcomes Understand the term Electrosurgery and Electrocautery Describe how monopolar and bipolar and argon energies differ Understand ORNAC Standards relating to safety and placement of dispersive pads on the patient. Describe the potential hazards of electrosurgery. Any energy that is used within the perioperative setting has the potential to start a fire. It is critical to ensure all safety parameters are in place. Electrosurgical Unit (ESU) Electrosurgical units (ESUs) have been used for many years to cut and coagulate tissue during surgical procedures. The ESU machines function on the basic principle of electricity. The 2 modes electrosurgery are Monopolar or Bipolar. Properties of Electricity Current - The flow of electricity measured in amps. Voltage - The force that moves the electrons from place to place measured in volts. Impedance – The opposition met by the electrons impeding the flow measured in ohms. Electricity must have a complete circuit or pathway so that the electron can flow. Two forms of electrical current used today - direct current (DC) and alternating current (AC). Direct Current (DC) - The electrons flow in one direct through a wire. The wire provides resistance and becomes hot. As the wire is held in contact with tissues coagulation or burring of a vessel will occur. The term for this is Electrocautery. Alternating Current (AC) – The electrons flow back and forth as polarity changes. Module 5: ESU In the Operating Room, electrosurgery devices use AC, which enters the body, causing the patient to become part of the circuit as the energy is returned to the source of the energy. Electrosurgical Modes Monopolar In the Monopolar system, electrical energy flows from the generator through the active electrode (the surgeon is holding the active electrode in the picture below) to the patient. The patient’s tissue provides impedance and controlled heat is generated and coagulation is achieved. The energy passes through the patient to a dispersive electrode (pad) or a patient return electrode (PRE). See image below of a pad placed on patient’s thigh. The pad is large so that energy is not concentrated enough to generate heat; preventing a burn. This energy is then returned to the generator and the circuit is then complete. If the dispersive electrode pad is tented, or if a small part of the pad is in contact with the patient’s body, electrical energy becomes concentrated and a burn can result. Two buttons are used to activate the system Blue - Coagulation mode Yellow - Cutting mode Active electrode – Handpiece / Cord Module 5: ESU If active electrode does not have manual buttons the surgeon will require a foot pedal to activate the energy. A typical machine has settings for both monopolar and bipolar, so there is no need to switch machines when the surgeon switches modes. A smoke evacuator must be used with Monopolar cautery, which removes the harmful, noxious ingredients that exist in the plume when tissue is vaporized. It protects the surgical team from inhaling harmful plume containing carcinogenic elements as well as viruses. Bipolar Electrosurgery Bipolar uses coagulation only and the settings are much lower, compared to monopolar. A pad (dispersive electrode) is not needed, as the current flows from one prong or tine of the forceps to the other prong, as it passes through the tissue located between these tines. Energy returns to the generator via the other prong completing the circuit. There is NO flow of electricity through the patient’s body. The vast majority of bipolar ESUs utilize a foot pedal to activate the bipolar cautery. Electrosurgical Dispersive Patient Return Electrode Pads Two types of dispersive pads used to ground the patient: dispersive monitoring pads and capacitive pads. Dispersive Monitoring Pads – An adhesive, one-time use pad that is used to protect the patient from dispersive electrode site burns caused by inadequate contact of the dispersive electrode. Placement of the pad is integral to prevent injuries. The pad should be placed over an area that is well vascularized, such as a thigh or buttocks. Sites with excessive hair, bony prominences, excessively dry skin, or adipose tissue should be avoided. Capacitive Pads – A large reusable pad that is placed on the OR table that the patient lies directly on. A normal sheet may also be placed over the pad and will not impede its effectiveness. These large pads are uniquely designed to use very low current densities thus eliminating the possibility of skin tissue damage. Capacitive pads are not at risk of becoming Module 5: ESU  tented during the procedure and cause a burn. A very common trade name pad is the green Megadyne pad. ESU in Endoscopic Surgery Both Monopolar and Bipolar are used during endoscopic surgery. There is no hand activation buttons and a foot peddle will be required for the surgeon to activate the energy. Three unique problems may arise when using electrocautery during endoscopic surgery, including insulation failure, direct coupling, and capacitive coupling. Insulation Failure – Endoscopic instruments may lose their insulated covers over time due to age or damage, such as a crack or break. The exposed part of the instrument allows electrical current t escape and burn untargeted surrounding tissue. See picture in Alexander’s p. 226 Figure 8.49. An insulation failure prevention strategy is routine maintenance and care of instruments. Direct Coupling – When an active electrode accidentally touches a non-insulated metal instrument or clip, allowing electrical energy to flow from one to the other (metal to metal sparking). Capacitive Coupling – A natural event that can happen when two conductors are separated from an insulator. Electrical current coming down active electrode can be transferred to another conductive surface, such as an organ, tissue, or conductive instrument. This can happen even if the insulation in between is intact. The use of hybrid instruments (plastic and metal) during endoscopy is avoided to minimize capacitive coupling. Surgeons need to be aware of capacitive coupling and try to keep conductors away from each other and have good insulation in between. See picture in Alexander’s p. 227 Figure 8.50. Argon Enhanced Electrosurgery An Argon-enhanced ESU combines argon gas with electrosurgical energy to improve the effectiveness of the electrosurgical current. Benefits Rapid coagulation of diffuse bleeding at the site with reduced blood loss Decreased blood loss Non-contact tissue coagulation Reduced surgical plume Reduced level of penetration by electrical energy and less adjacent tissue damage Care must be taken when this is used in combination with MIS laparoscopic surgery as over inflation / over pressurization of the abdomen and the addition of argon gas insertion could result in a gas embolism. Module 5: ESU  Other Electro thermal Sealing Devices Ligasure (Electro Thermal Bipolar Vessel) ORNAC Standards Surgical Energy DO’S Scrub Role Circulating Role Provide a clean and dry insulated The pad shall be placed after the surface (holster) for the active patient is positioned and protected electrode (handpiece) to be placed from potential fluid spills. when it is not in use. Remove excessive, oils/lotions prior Be aware of any unusual need to putting the pad on the patient. for more power. Power setting Open the sealed pad once you are should be at the lowest level ready to place on the patient. For possible. pre-gelled patient pads check the Carefully check the cords plate for expiry date, apply the including power cable, active appropriate size dependent on electrode cable for cracks or patient. deterioration. Apply to a well-muscled, clean, dry Keep active electrode blade clean of area as close to the operative site as tissue/eschar buildup using cautery possible with uniform contact. cleaner (scratch pad) Always check the patient site after removing the pad and document site condition. DO NOT Scrub Role Circulating Role Do not use active electrode in an Do not place the disposal dispersive oxygen-enriched environment pad on a wet site. Do not re-adjust or re-apply Module 5: ESU  dispersive pad. Avoid placing pad on tattoos (if possible) Do not use tape to secure disposal dispersive pads. Do not kirk or wrap disposal dispersive pad cord or active cord around any objects. Do not cut or adjust the disposal dispersive pad to size for infants. Recommendations to Avoid Electrosurgical Patient Complications in MIS Inspect instrument insulation carefully Use lowest possible power setting Use a low voltage waveform (cut) Use brief intermittent activation vs. prolonged activation Do not activate in open circuit Do not activate in close proximity or direct contact with another instrument Use bipolar electrosurgery when appropriate Select an all metal cannula system as the safest choice. Do not use hybrid cannula systems that mix metal with plastic. Utilize available technology, such as a tissue response generator to reduce capacitive coupling or an active electrode monitoring system to eliminate concerns about insulation failure and capacitive coupling. Module 5: ESU