Editing Pulseless electrical activity (section)

{{Infobox medical condition (new)
| name = Pulseless electrical activity
| synonyms = '''Electromechanical dissociation'''
| image = Pulseless electrical activity EKG.svg
| caption = A drawing of what a rhythm strip showing PEA could look like
| pronounce = 
| field = [[Emergency Medicine]], [[Cardiology]]
| symptoms = Loss of Consciousness, Respiratory Arrest, Sudden death
| complications = [[Death]]
| onset = 
| duration = 
| types = 
| causes = 
| risks = Certain drug overdoses, [[Heart attack]], Chest trauma, [[Pulmonary Embolism]], Hypoxia, [[Hypothermia]], [[Hypokalemia]], [[Hyperkalemia]], [[Hypovolemia]]
| diagnosis = [[Electrocardiogram]]
| differential = [[Cardiac arrest]]
| prevention = 
| treatment = [[Cardiopulmonary Resuscitation]]
| medication = [[Epinephrine]]
| prognosis = Poor (2-5% outside of the hospital)
| frequency = Incidence out-of-hospital: 22% to 30% of cardiac arrest events 
Incidence in-hospital: 35% to 40% of cardiac arrest events
| deaths = 
}}
'''Pulseless electrical activity''' ('''PEA''') is a form of [[cardiac arrest]] in which the [[electrocardiogram]] shows a heart rhythm that should produce a [[pulse]], but does not. Pulseless electrical activity is found initially in about 20% of out-of-hospital cardiac arrests<ref>{{Cite journal |last1=Bergström |first1=Mattias |last2=Schmidbauer |first2=Simon |last3=Herlitz |first3=Johan |last4=Rawshani |first4=Araz |last5=Friberg |first5=Hans |date=December 2018 |title=Pulseless electrical activity is associated with improved survival in out-of-hospital cardiac arrest with initial non-shockable rhythm |url=https://pubmed.ncbi.nlm.nih.gov/30352246/ |journal=Resuscitation |volume=133 |pages=147–152 |doi=10.1016/j.resuscitation.2018.10.018 |issn=1873-1570 |pmid=30352246|s2cid=53025153 }}</ref> and about 50% of in-hospital cardiac arrests.<ref>{{Cite journal |last1=Norvik |first1=A. |last2=Unneland |first2=E. |last3=Bergum |first3=D. |last4=Buckler |first4=D. G. |last5=Bhardwaj |first5=A. |last6=Eftestøl |first6=T. |last7=Aramendi |first7=E. |last8=Nordseth |first8=T. |last9=Abella |first9=B. S. |last10=Kvaløy |first10=J. T. |last11=Skogvoll |first11=E. |date=2022-07-01 |title=Pulseless electrical activity in in-hospital cardiac arrest – A crossroad for decisions |url=https://www.sciencedirect.com/science/article/pii/S0300957222001423 |journal=Resuscitation |language=en |volume=176 |pages=117–124 |doi=10.1016/j.resuscitation.2022.04.024 |pmid=35490937 |hdl=10810/57896 |issn=0300-9572|hdl-access=free }}</ref>

Under normal circumstances, electrical activation of muscle cells precedes mechanical contraction of the heart (known as ''electromechanical coupling''). In PEA, there is electrical activity but insufficient [[cardiac output]] to generate a pulse and supply blood to the organs, whether the heart itself is failing to contract or otherwise.<ref name="2010AHA" /> While PEA is classified as a form of cardiac arrest, significant cardiac output may still be present, which may be determined and best visualized by bedside ultrasound ([[echocardiography]]).

<!-- Treatment and prognosis -->
[[Cardiopulmonary resuscitation]] (CPR) is the first treatment for PEA, while potential underlying causes are identified and treated. The medication [[epinephrine]] (aka adrenaline) may be administered.<ref name="2010AHA" /> Survival is about 20% if the event occurred while the patient was already in the hospital setting.<ref name=Bal2016>{{cite journal|last1=Baldzizhar|first1=A|last2=Manuylova|first2=E|last3=Marchenko|first3=R|last4=Kryvalap|first4=Y|last5=Carey|first5=MG|title=Ventricular Tachycardias: Characteristics and Management.|journal=Critical Care Nursing Clinics of North America|date=September 2016|volume=28|issue=3|pages=317–29|pmid=27484660|doi=10.1016/j.cnc.2016.04.004}}</ref>