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Three Part Question

In [adult ED patients receiving a Taser discharge] is [monitoring] necessary [to detect cardiac dysrhythmias].

Clinical Scenario

A 25 year old patient is subdued by law enforcement with the use of a Taser device. He is brought to your Emergency Department for further evaluation. You would like to know what type of cardiac monitoring is necessary (and for how long).

Search Strategy

Ovid MEDLINE(R) 1950 to June Week 1 2009, Embase 1980 to 2009 Week 23 using multifile searching:
[(exp stun gun.mp or taser.mp or electromuscular incapacitation device.mp or electrical weapon.mp or energy device.mp) AND (exp arrhythmias, cardiac/ or cardiac.mp or arrhythmia.mp or exp monitoring, physiologic/ or monitoring.mp or exp electrocardiography/)]. LIMIT to human AND English.
The Cochrane Library Issue 2 2009: (taser):ti,ab,kw OR (stun gun):ti,ab,kw OR (electrical weapon):ti,ab,kw 1 record 0 relevant

Search Outcome

34 unique papers were found of which 4 were relevant to the three part question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Vilke GM et al, 2008, USA	32 healthy volunteer subjects receiving a Taser X26 discharge	Prospective observational	Minor changes in heart rate, PR and QT interval	No clinically relevant ECG changes	Unable to continuously monitor subjects with a 12 lead monitor. Changes may have resolved by one minute. Subjects were generally healthy and free of disease, which may not mimic true population. Duration of Taser activation was limited to 5 seconds, which may not represent what occurs in the field.
Ho JD et al, 2006, USA	66 Human subjects after standard conducted electrical weapon application 32 underwent ECG assessment	Prospective observational	Troponin elevations	One subject had a troponin of 0.6 ng/ml. no evidence of acute myocardial infarction found	Study population may not be reflective of general population. Resting population may not be representative of true agitated or stressed population. Single, five second application of CEW may not be representative of true events in the field.
			ECG	No changes noted
Levine SD et al, 2007 , USA	Humans with voluntary exposure to Taser X 26	Prospective observational	Changes in heart rate and QT interval	No significant changes	Relatively small sample size. Single lead electrocardiographic data. 12 lead might provide more accurate tracings. Healthy patient population at rest is not representative of the true population of Taser victims. Single 5 second shock may not be representative of what occurs in the field. There was also significant motion artifact during the shock itself, which may obscure momentary dysrhythmias.
Ho JD et al, 2008, USA	33 adult male volunteers underwent a 10 second Taser discharge placed across the ideal cardiac axis (right upper sternum to the apex) 11 of 33 had significant medical problems requiring medication	Observational	Echocardiography	No dysrhythmias noted	Movement artefact meant that echocardiographic view was poor in 38.3% (12/33) of subjects during the actual Taser discharge

Comment(s)

There is a theoretical concern that administration of a conducted electrical weapon or Taser has the potential to cause significant cardiac dysrhythmias and possibly sudden death. These four studies, by means of cardiac monitoring and measurement of skin-to-heart distance, assess for the potential for induction of dysrhythmias and cardiac damage. There are several common limitations of these studies, including selection bias of healthy subjects. Another common weakness is single firing and discharges less than five seconds, which may not be representative of true events in the field. Larger studies are needed, as well as studies involving a better representation of the physiologic state of typical Taser victims.

Clinical Bottom Line

Based on the current evidence, however, it appears that no further cardiac evaluation is necessary in patients with a normal sinus rhythm in the Emergency Department after receiving a Taser discharge.

References

1. Vilke GM. Sloane C. Levine S. Neuman T. Castillo E. Chan TC. Twelve-lead electrocardiogram monitoring of subjects before and after voluntary exposure to Taser X26. The American Journal of Emergency Medicine 26(1):1-4, 2008 Jan.
2. Ho JD. Miner JR. Lakireddy DR. Bultman LL. Heegaard WG. Cardiovascular and Physiologic Effects of Conducted Electrical Weapon Discharge in Resting Adults. Academic Emergency Medicine 13(6):589-95, 2006 Jun.
3. Levine SD. Sloane CM. Chan TC. Dunford JV. Vilke GM. Cardiac monitoring of human subjects exposed to Taser. Journal of Emergency Medicine 33(2):113-7, 2007 Aug.
4. Ho JD, Dawes DM, Reardon RF, Lapine AL, Dolan BJ. Lundin EJ, Miner JR. Echocardiographic evaluation of a TASER-X26 application in the ideal human cardiac axis. Acad Emerg Med 2008;15:838-44.