1. Without reference, identify principles about Electrosurgical Units with at least 70 percent accuracy.

2.  Purpose of an Electrosurgical Unit (ESU) ◦ A system that uses radio frequency to  Sever tissue  Stop bleeding (hemeostasis) ◦ Units operate in the range of 300 kHz to 3 MHz

3.  Types ◦ Monopolar  Active electrode - one side of the generator  The electrosurgical effect takes place at the active electrode only  Typically offers the best alternative for wide surface coagulating and dissection of tissue  Return electrode  The other side is known as o patient plate o Reference electrode o dispersive electrode

4.  No electrical effect is intended or desired  Needed to complete the electrical circuit  Placement  As close as possible to the surgical site  Minimize the distance that the current will need to travel through the body ◦ Bipolar  Both sides of the generator are connected to a surgical handpiece  Allows for better current control  The current passes between two poles of a forceps rather than through the entire body

5.  Surgical Effects and Operational Modes ◦ Coagulation  Used to control or stop bleeding  It is a low power technique  Uses an interrupt current to supply controlled dehydration  Can also be used for destroying undesirable tissue masses ◦ Cutting  Heats tissue so rapidly that cells explode and contents vaporize leaving an incision  When used, the electrode is separated from the tissue by a thin layer of steam  Used like a stainless steel scalpel  Little or no control over bleeding

6. ◦ Blend  Hybrid of cut and coagulate  Used when surgeon desires more hemeostasis effect than cut provides  This mode saves time, as only one pass with electrode is necessary ◦ Spray (fulguration)  Used for rapid control of bleeding across a wide area  A non-contact type of coagulation  The current sparks or jumps from active electrode to the tissue  Uses  To destroy surface layers of cells in the bed from which a lesion has been removed  Ideal for sealing off hidden bleeders due to their path of least resistance

7.  Power ◦ Can be varied for all modes ◦ Setting depends on tissue type, procedures, and the type of electrode used ◦ Low power  Neurosurgery  Oral ◦ Medium power  General surgery  Abdominal opening ◦ High power  Open the chest  Mastectomies

8.  Precautions ◦ Return plate burns  Protect the patient from being burned  The pad must have as much direct contact with the patient as possible  Edge effect – use a pad that has a larger edge to lower current density  Monitor Systems  Used to prevent a patient from a pad related burn  The ESU is designed to send a small current up one side of the pad through the patient’s skin and back through the other side of the pad  If the ESU senses a change in resistance from the pad to patient contact it will set off an alarm

9. ◦ Alternate current path burns  When the pencil is activated there is opportunity for RF leakage interference  Wrapping surgical cable around metallic material and securing it to a flammable material may lead to a fire hazards  You need to be aware of the hazards of RF leakage and choose products that are shielded properly from these hazards  Prevent electrical shock  Know the basic principles of electricity, current density, and the path of least resistance  Never activate in open circuit