LETTERS TO THE EDITOR: Letters & Announcements
To the Editor:
Barker and Polson (1) continue the tradition in the anesthesia literature of addressing the hazards of surgical fires and present cogent and timeless recommendations for surgical fire prevention. Their report was based on their investigation of a fire during head surgery under local anesthesia with monitored anesthesia care at University Medical Center (UMC) in Tucson, AZ. We disagree with their conclusion as to the cause of the reported fire and comment here on their testing methodology. We do, however, wholly support the recommendations presented in the article. As such, we present additional resources for recommendations on surgical fire prevention.
Our constructive criticism of the testing performed by Barker and Polson is based on our more than two decades of investigating and publishing on surgical fires and on our development of the first draft standard for electrosurgical equipment and accessories under contract to the FDA in the late 1970s. Our comments on fire causation in the reported case are based on our detailed field investigation of the fire at UMC and on our examination of the burned surgical materials and devices. One of the authors of this letter subsequently presented a combined anesthesia/surgical grand rounds on surgical fires at UMC some months after the incident and had the pleasure of discussing surgical fires with Dr. Barker at that time.
Barker and Polson postulate that electrosurgical ignition of latent prepping agent alcohol vapors caused the UMC fire. This scenario is supported neither by the physical evidence from the case nor by the pattern of burns on the patient. Their conclusions are based on fire recreation testing that they performed. Accurate recreation of the surgical setting for fire recreation is admittedly difficult. However, their surgical recreation did not represent a clinically valid surgical setting in several important technical aspects, including:
- * Not using a body-temperature manikin for the assessment of evaporation characteristics of alcohol in the prepping agents.
- * Not performing the alcohol evaporation characteristic assessment in a room with high ventilation typical of an operating room.
- * Using aluminum foil at the point of electrosurgical sparking rather than skin with a subcutaneous fat layer (such as pig skin), which gives a more realistic electrosurgical flame/arc.
- * Not considering the dynamics of gas flow beneath surgical towels and drapes that can cause almost pure oxygen to blow directly into the fenestration and onto the target tissue during head and neck surgery.
Rather than the alcohol vapor scenario postulated, we believe that the specific risk factor for the cause of the UMC fire was the supplemental oxygen delivered to the patient via an open oxygen mask on the face. With this oxygen present beneath the head drapes, electrosurgical sparks or flame/arc irradiance ignited either the exposed folded edge of the reusable cotton towel within the fenestration or the gauze sponge held by the surgeon immediately adjacent to the target tissue (which then ignited the edge of the towel). The immediate rapid spread of the fire on the underside of the towels and drapes was caused by the oxygen-enriched phenomenon called “surface fiber flame propagation”(2). Prevention of fire under such operating conditions can be accomplished by delivering an FiO2 of <30% to the mask or, if 100% oxygen delivery is indicated, by temporarily ceasing oxygen flow (or decreasing to 30% FiO2) 60 seconds before the use of electrosurgery, electrocautery, or surgical laser (3,4).
For additional surgical fire prevention recommendations, readers are directed to several of ECRI’s many published articles on surgical fires (5,6,7) and to the well-known anesthesia text by Dorsch and Dorsch (8). The full text of many published articles on surgical fires is also available at ECRI’s free clinical Web site (called Medical Device Safety Reports) at www.mdsr.ecri.org (use the search term “fires”). Technical discussions of surgical fires are available elsewhere (2,9), as are discussions and recommendations directed specifically to the surgical community (10).
As Barker and Polson observe, the UMC case did have a unique and specific chain of events leading up to the fire, as do most surgical fires. However, the precursors related to open oxygen use and the resulting fire are, unfortunately, not unique to this type of adverse event.
Mark E. Bruley
Albert L. de Richemond, MS, PE
1. Barker SJ, Polson JS. Fire in the operating room: a case report and laboratory study. Anes Analg 2001; 93: 960–5.
2. Bruley ME, Lavanchy C. Oxygen-enriched fires during surgery of the Head and Neck. In: Symposium on Flammability and Sensitivity of Material in Oxygen-Enriched Atmospheres: Fourth Volume, ASTM STP 1040, Joel M. Stoltzfus, Frank Benz, and Jack Stradling, eds. American Society for Testing and Materials, Philadelphia, 1989:392.
3. ECRI. Surgical fires: Learning prevention. Health Devices 1999; 28 (9): 372–3.
4. ECRI. Fires during surgery of the head and neck area. Health Devices 1979; 9 (2): 50–52.
5. ECRI. Fires from oxygen use during head and neck surgery [hazard]. Health Devices 1995; 24 (4): 155–7.
6. ECRI. Fire hazard created by the misuse of Duraprep solution [hazard]. Health Devices 1998; 27 (11): 400–2.
7. ECRI. Surgical fire hazards of alcohol. Health Devices 1999; 28 (7): 286.
8. Hazards of anesthesia machines and breathing systems. In: Dorsch JA, Dorsch SE. Understanding Anesthesia Equipment, 2nd ed. Williams and Wilkins: Baltimore/London, 1984:314.
9. de Richemond AL, Bruley ME. Insidious iatrogenic oxygen enriched atmospheres as a cause of surgical fires. In: Janoff D, Stoltzfus J, eds. Flammability and sensitivity of materials in oxygen-enriched atmospheres, Sixth volume. ASTM STP 1197. Philadelphia: American Society for Testing and Materials, 1993: 66–73.
10. de Richemond AL, Bruley ME. Head and neck surgical fires. In: Eisele DW, ed. Complications in head and neck surgery. St. Louis: Mosby-Year Book, 1993.