Increased Hematocrit After Applications of Conducted Energy Weapons (Including TASER^® Devices) to Sus scrofa*

Abstract

Conducted energy weapons (CEWs) are used by law enforcement personnel to incapacitate individuals quickly and effectively, without intending to cause lethality. CEWs have been deployed for relatively long or repeated exposures in some cases. In laboratory animal models, central venous hematocrit has increased significantly after CEW exposure. Even limited applications (e.g., three 5-sec applications) resulted in statistically significant increases in hematocrit. Preexposure hematocrit was significantly higher in nonsurvivors versus survivors after more extreme CEW applications. The purpose of this technical note is to address specific questions that may be generated when examining these results. Comparisons among results of CEW applications, other electrical muscle stimulation, and exercise/voluntary muscle contraction are included. The anesthetized swine appears to be an acceptable animal model for studying changes in hematocrit and associated red blood cell changes. Potential detrimental effects of increased hematocrit, and considerations during law enforcement use, are discussed.

Pathophysiologic changes due to TASER® devices versus excited delirium: Potential relevance to deaths-in-custody?

“…Potential causes (prior to any use of an ECD) include psychological stress, endocrinopathy, diabetes, chronic alcohol abuse, cocaine use, or use of opiates. 93 There is also an increased lethality of cocaine when used in combination with heroin, opiates, and alcohol. 109 …”

“…93 Although polycythemia increases blood oxygen content, this potential benefit may be counterbalanced by a decrease in cardiac output, which will, in turn, adversely affect pulmonary diffusion and alveolar ventilation.…”

“…The mechanisms of these changes in hematocrit have not been determined, but potential candidates have been reviewed previously. 93 These include: a) increased capillary hydrostatic pressure due to effects of muscle contraction on venules (with plasma fluid pushed into the extravascular space); b) release of metabolic waste products from muscles (with increased osmolality of the interstitial space); and c) splenic contraction.…”

“…67 Hyperglycemia may result in decreased erythrocyte deformability, 106 which can occur concurrently with increased hematocrit. 93 It is unknown whether increased blood glucose is a function of physical struggle, excited delirium, drug intoxication, or ECD applications during law-enforcement situations. Alcohol, 107 opioids, and opioid analogs 108 can, by themselves, result in hyperglycemia.…”

Acute pathophysiological influences of conducted electrical weapons in humans: A review of current literature

“…Even though some animal studies point out certain potential risk factors after an exposure to CEWs, such as increased hematocrit, acidosis or lack of effective respiration [9][10][11][12][13], these Conducted electrical weapons (CEWs) deliver short high-voltage, low current energy pulses to temporarily paralyze a person by causing muscular contraction.…”