Spark-generating properties of electrode gels used during defibrillation. A potential fire hazard
R. S. Hummel 3rd, J. P. Ornato, S. M. Weinberg and A. M. Clarke
Division of Biomedical Engineering, Medical College of Virginia, Richmond 23298.
After a defibrillation attempt started a fire in an oxygen-enriched
intensive care unit environment, seven popular electrode gels were tested
for spark-generating properties by repeated 360-J electrical discharges
into a 50-omega test load. Gels with low initial impedance (7 +/- 1 omega)
allowed a high current flow (51 +/- 1 A), maintained a cool temperature (27
degrees C to 33 degrees C), and did not spark. Gels with high initial
impedance (125 +/- 14 omega) allowed less current (26 +/- 2 A), heated to
52 degrees C +/- 2 degrees C, liquified, and generated an electrical spark
after the fourth or fifth discharge. Federal standards should be developed
to identify and label electrode gels that can be used safely for
high-current applications such as defibrillation.
