Prolonged TASER use on exhausted humans does not worsen markers of acidosis

Abstract

Objective: There are safety concerns about TASER conducted electrical weapon (CEW) use on humans, and there have been media reports of adverse human outcomes after CEW exposure. Conducted electrical weapons are often used on physically exhausted subjects. A single CEW application of a CEW is generally accepted to be 5 seconds of exposure. Some exposures in reality involve more than 5 seconds. We sought to determine if a prolonged (15 seconds) CEW exposure on exhausted humans caused acidosis, hyperkalemia, serum lactate change, or troponin change.

Methods: This was a prospective study of generally healthy human volunteers. Medical histories and baseline serum values were obtained, and several of the volunteers did have acute or chronic medical problems. Subjects underwent an exercise protocol until subjective exhaustion. Exhaustion was defined by the volunteer no longer being able to perform the exercise at a given pace. Blood was drawn immediately (defined as within 20 seconds) after exercise and was immediately followed by a 15-second CEW exposure. Blood was drawn immediately after exposure and again at 16 to 24 hours after exposure. Blood was analyzed for pH, pco(2), potassium, lactate, and troponin. Data were compared using Wilcoxon signed rank tests.

Results: There were 38 subjects enrolled with an average age of 39 years. The following health conditions were reported among the volunteers: hypertension (2), gastritis/reflux (2), active respiratory tract infections (3), asthma (2), chronic muscular pain conditions (4), pituitary adenoma (1) and glaucoma (1). Sixteen volunteers reported use of prescription medication at the time of their participation. The median initial pH of 7.38 (interquartile range [IQR], 7.35-7.40) decreased to 7.23 (IQR, 7.19-7.31) immediately after exercise. Immediately after exposure, median pH was 7.22 (IQR, 7.18-7.25). It was 7.39 (IQR, 7.37-7.43) at 24 hours. The pCO2 increased from 46.3 (IQR, 43.0-54.5) to 57.4 (IQR, 49.9-67.7) immediately after exercise, decreased to 51.3 (IQR, 44.4-65.0) immediately after exposure, and was 46.3 (IQR, 42.7-51.7) at 24 hours. Lactate increased from a median of 1.65 (IQR, 1.14-2.55) to 8.39 (IQR, 6.98-11.66) immediately after exercise, increased to 9.85 (IQR, 7.70-12.87) immediately after exposure, and was 1.02 (IQR, 0.91-1.57) at 24 hours. Serum potassium increased from 3.9 (IQR, 3.8-4.4) to 4.2 (IQR, 4.0-4.9) immediately after exercise, decreased to 3.8 (IQR, 3.7-4.4) immediately after exposure, and was 4.1 (IQR, 3.9-4.6) at 24 hours. No troponin elevations were detected.

Conclusion: Prolonged CEW application on exhausted humans was not associated with worsening change in pH or troponin. Decreases in pCO2 and potassium and a small increase in lactate were found. Worsening acidosis theories due to CEW use in this population are not supported by these data.