Chapter 23: Electrical Safety and Defibrillation
Preoperatively, a patient is wearing a metal umbilical (belly button) ring. The planned surgical procedure is on the left arm and it requires the use of an electrosurgical unit (ESU). The patient is informed of potential risks but refuses to remove the item. Of the following options, what is the most appropriate course of action?
(A) no alteration is required as the line isolation monitor (LIM) will detect potential microshock
(B) lift and tape the umbilical ring so the smallest possible area is in contact with the skin
(C) tape the umbilical ring flat to the abdomen
(D) place the dispersive electrode (grounding pad) on the opposite side of the surgical site
(E) have the surgeon use a unipolar ESU rather than a bipolar ESU
The answer is C. An electrosurgical unit (ESU) operates at high frequencies and applies high current via a small surface area electrode. Unipolar electrosurgery applies electric current through one electrode that is collected by a dispersive electrode (grounding pad) placed remote from the surgical site. Bipolar electrosurgery applies and collects electric current through a set of forceps; there is no need for a dispersive electrode (grounding pad).
Metal jewelry can potentially cause a burn when an ESU is used, as the metal jewelry can reconcentrate some of the electric current passing nearby. Remove all metal jewelry to eliminate this risk. If this is not possible, tape metal jewelry against the skin with as large a contact area as possible—in this case, tape the umbilical ring flat to the abdomen. Also, for unipolar electrosurgery, place the dispersive electrode (grounding pad) so that jewelry is not in the path of the current traveling to the grounding pad; in this case it should be placed on the same side as the surgical site. A line isolation monitor will not protect a patient wearing metal jewelry from potential burn risks.
Ref: Miller RD. Miller's Anesthesia, 8th ed. Philadelphia, PA: Elsevier; 2015.
An operating room is equipped with a line isolation monitor (LIM). What does activation of the LIM alarm mean?
(A) The ground fault circuit interrupter (GFCI) is now active.
(B) The patient is grounded.
(C) The power supply is grounded.
(D) A piece of electrical equipment is grounded.
(E) There is significant static buildup on the operating room floor.
The answer is C. Power ...