Electrosurgical/Surgical Diathermy Units Copyright 2007

Electrosurgical/Surgical Diathermy Units Electrosurgical Basics Electrosurgical Burns Laparoscopic Accidents Injuries to Medical Staff Fires Copyright 2007

Some Basic Electrosurgery Facts Health Canada Talks, Session 10 Some Basic Electrosurgery Facts 23-25 February 2005 Used in about 80% of all surgical procedures Very effective surgical tool Cutting Coagulation Fulguration Not well understood by clinicians Commonly seen in FDA and ECRI problem reporting databases Cutting Typically, small-surface active electrode tip (e.g., needle, wire loop, edge of flat blade) Initially applied (in contact) with target tissue Sufficient amount of steam from vaporized tissue separates electrode from tissue Sparks through vapor layer between active electrode and tissue carry cutting current Relatively low voltage compared to coagulation Contact coagulation (dessication) Direct contact between active electrode and target tissue Results in vaporization of cellular water, denaturation of protein, and drying of tissue Achieved with broad surface active electrode tip and low-voltage mode Produces white coagulum Frequently misapplied for cutting and dessication Arcing (Fulguration) Arcs (sparks) char bleeding tissue surface Intensely concentrated current at small points on tissue surface Active electrode tip held slightly above bleeding tissue surface Produces black coagulum High-voltage mode Greatest potential for interference with other medical devices Copyright 2007 ALdeR

Basic Principles of Electrosurgery Health Canada Talks, Session 10 23-25 February 2005 Basic Principles of Electrosurgery Frequency Typically operate at frequencies between 300 KHz and 1 MHz 300 kHz to 1Mhz avoids complication of electrical nerve stimulation Under certain conditions (e.g., arcing between two dry metal surfaces) low frequency components (<10 KHz) can be introduced with the delivered electrical current Current conducted through a complete circuit including the generator, insulated cables, electrodes, and the patient Copyright 2007 ALdeR

Monopolar Electrosurgery Copyright 2007

Bipolar Electrosurgery Health Canada Talks, Session 10 23-25 February 2005 Bipolar Electrosurgery Electrosurgical Unit Current Flow Current conducted between two electrodes on the same instrument (e.g., forceps) Dispersive return electrode is not needed Current is confined to target tissue at the surgical site between the two electrodes Allows for lower output power than monopolar electrosurgery Generally safer than monopolar electrosurgery – but procedures are often performed on more “delicate” tissue Tissue between tips of forceps Copyright 2007 ALdeR

Electrosurgery Safety Features Continuity Monitor Verifies that a return electrode is connected to electrosurgical unit Cannot detect if return electrode is disconnected from or in poor contact with the patient Copyright 2007

Electrosurgery Safety Features Return Electrode Contact Quality Monitor (RECQM) Offers better level of protection than continuity monitor Assures that good contact exists between the dispersive electrode and patient ECRI strongly recommends using electrosurgical units with RECQM Copyright 2007

Dual Plate Return Electrodes Health Canada Talks, Session 10 23-25 February 2005 Dual Plate Return Electrodes Interrogation current flows between each plate of the electrode and the patient. If one side is partially detached from the patient, an alarm will sound. Single-foil return electrodes must not be used with RECQM safety feature Dual-foil return electrodes must be used with RECQM Return electrode site should be properly prepped prior to placing on patient Area should be shaven to remove excess hair and cleaned to provide optimal electrode-patient contact Electrode should be properly oriented on patient with respect to surgical site Copyright 2007 ALdeR

Electrosurgical Accidents Skin Burns Fires, Explosions Prepping Solutions, Surgical Drapes, Bowel Gas Oxygen-Enriched Atmosphere Active Electrode Arc or Spark Too Much/Too Little Power Delivered Organ Perforations Copyright 2007

A Misconnection Problem Health Canada Talks, Session 10 23-25 February 2005 A Misconnection Problem See Hazard report: monopolar activation more power than expected bowel perforation Copyright 2007 ALdeR

Electrosurgical Accidents Health Canada Talks, Session 10 23-25 February 2005 Electrosurgical Accidents Argon Beam Coagulators Gas Embolism Interference (EMI) ESU as “Source” of EMI User Injuries Hand sensation Alternate pathways Hand sensation: mostly during urologic procedures (TURP) capacitive coupling of instrument handle Wet environment startle injuries Only 2 cases in US history of “muscular degeneration due to ESU. There is not enough current to cause extensive injury. History of use does not support MDs’ contention. Copyright 2007 ALdeR

Electrosurgical Injuries Return Electrode Issues Poor electrode placement Lack of skin prep Complete or partial removal of return electrodes Skin reactions to adhesives “Edge effects” High electrosurgical currents and long activation times Copyright 2007

Electrosurgical Injuries Active Electrode Issues Insulation surrounding conductive shaft Breakdown Repeated Sterilization Cuts, Nicks, Abrasions Capacitive Coupling Electrical current induced by means of capacitance to other instruments or tissues Inadvertent activation! Copyright 2007

Electrosurgical Injuries Active Electrode Organ Perforations Alternate Site Burns (Use a Holster!) Laparoscopic Active Electrodes Laparoscopic Cannula Burns Failure to Use Activation Tone Copyright 2007

Active Electrode Accidents Inadvertent activation of the ESU due to unintentional switch activation User places active electrode on the patient or the surgical drape between intended activations Safety holster not used Audible activation tone volume is set too low Insulation failure along shaft during procedures, such as tonsillectomy causing burn to tissue inside mouth or to lip User makes direct contact with nontarget tissue Copyright 2007

Electrosurgical Injuries Return Electrode Poor Site Preparation Poor Application technique Non-uniform Conductivity Repositioning Patient Electrode Copyright 2007

Return Electrode Accidents Burns Use of electrolytic (conductive) distention/irrigation media during TURP Conductive solution may render electrosurgery less effective Disperses current away from intended surgical site Lower surgical effect may lead user to increase power output of ESU Conductive solution lowers impedance at active electrode, elevating current Increased power and lower impedance increases current through dispersive return electrode Copyright 2007

Laparoscopic Electrosurgery Monopolar vs. Bipolar Current leakage though cannula Insulation breakage Fire Copyright 2007

Laparoscopic Injuries Inadvertent tip to tissue contact Insulation failures Capacitive coupling Trocar insertion sites Device interference Resulting in bowel perforations, excess bleeding, damage to nontarget tissue, etc. Copyright 2007

ESU-caused Fires Heat, sparks, flaming gases Rarely a device failure – “a known complication” Copyright 2007