Pulseless electrical activity

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Pulseless electrical activity
Other namesElectromechanical dissociation
Pulseless electrical activity EKG.svg
A drawing of what a rhythm strip showing PEA could look like
Specialty Cardiology   OOjs UI icon edit-ltr-progressive.svg

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 [1] and about 50% of in-hospital cardiac arrests. [2]

Contents

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. [3] 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).

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. [3] Survival is about 20% if the event occurred while the patient was already in the hospital setting. [4]

Signs and symptoms

Pulseless electrical activity leads to a loss of cardiac output, and the blood supply to the brain is interrupted. As a result, PEA is usually noticed when a person loses consciousness and stops breathing spontaneously. This is confirmed by examining the airway for obstruction, observing the chest for respiratory movement, and feeling the pulse (usually at the carotid artery) for a period of 10 seconds. [3]

Causes

These possible causes are remembered as the 6 Hs and the 6 Ts. [5] [6] [7] See Hs and Ts

The possible mechanisms by which the above conditions can cause pulseless in PEA are the same as those recognized as producing circulatory shock states. These are (1) impairment of cardiac filling, (2) impaired pumping effectiveness of the heart, (3) circulatory obstruction and (4) pathological vasodilation causing loss of vascular resistance and excess capacitance. More than one mechanism may be involved in any given case.[ citation needed ]

Diagnosis

Pulseless electrical activity, it is possible to observe by invasive blood pressure (red) the transition from a normal mechanical activity of the heart, which progressively changes in rhythm and contractile quality to asystole, even in the presence of normal electrical activity (green), also confirmed by the pulse oximeter detection even if with artifacts (blue) Dissociazione elettromeccanica (PEA).svg
Pulseless electrical activity, it is possible to observe by invasive blood pressure (red) the transition from a normal mechanical activity of the heart, which progressively changes in rhythm and contractile quality to asystole, even in the presence of normal electrical activity (green), also confirmed by the pulse oximeter detection even if with artifacts (blue)

The absence of a pulse confirms a clinical diagnosis of cardiac arrest, but PEA can only be distinguished from other causes of cardiac arrest with a device capable of electrocardiography (ECG/EKG). In PEA, there is organised or semi-organised electrical activity in the heart as opposed to asystole (flatline) or to the disorganised electrical activity of either ventricular fibrillation or ventricular tachycardia. [3]

Treatment

Cardiac resuscitation guidelines (ACLS/BCLS) advise that cardiopulmonary resuscitation should be initiated promptly to maintain cardiac output until the PEA can be corrected. The approach in treatment of PEA is to treat the underlying cause, if known (e.g. relieving a tension pneumothorax). Where an underlying cause for PEA cannot be determined and/or reversed, the treatment of pulseless electrical activity is similar to that for asystole. [3] There is no evidence that external cardiac compression can increase cardiac output in any of the many scenarios of PEA, such as hemorrhage, in which impairment of cardiac filling is the underlying mechanism producing loss of a detectable pulse.[ citation needed ]

A priority in resuscitation is placement of an intravenous or intraosseous line for administration of medications. The mainstay of drug therapy for PEA is epinephrine (adrenaline) 1 mg every 3–5 minutes. Although previously the use of atropine was recommended in the treatment of PEA/asystole, this recommendation was withdrawn in 2010 by the American Heart Association due to lack of evidence for therapeutic benefit. [3] Epinephrine too has a limited evidence base, and it is recommended on the basis of its mechanism of action.[ citation needed ]

Sodium bicarbonate 1meq per kilogram may be considered in this rhythm as well, although there is little evidence to support this practice. Its routine use is not recommended for patients in this context, except in special situations (e.g. preexisting metabolic acidosis, hyperkalemia, tricyclic antidepressant overdose). [3]

All of these drugs should be administered along with appropriate CPR techniques. Defibrillators cannot be used to correct this rhythm, as the problem lies in the response of the myocardial tissue to electrical impulses.[ citation needed ]

Related Research Articles

<span class="mw-page-title-main">Bradycardia</span> Heart rate below the normal range

Bradycardia is a slow resting heart rate, commonly under 60 beats per minute (BPM) as determined by an electrocardiogram. It is considered to be a normal heart rate during sleep, in young and healthy or elderly adults, and in athletes.

<span class="mw-page-title-main">Cardiac arrest</span> Sudden stop in effective blood flow due to the failure of the heart to beat

Cardiac arrest occurs when the heart stops beating. It is defined as cessation of normal circulation of blood due to failure of the heart to pump effectively. It is a medical emergency that, without immediate medical intervention, will result in cardiac death within minutes. When it happens suddenly, it is called sudden cardiac arrest. Cardiopulmonary resuscitation (CPR) and possibly defibrillation are needed until further treatment can be provided. Cardiac arrest results in a rapid loss of consciousness, and breathing may be abnormal or absent. Coma can occur as a result of the cardiac arrest when the brain goes too long without oxygen.

<span class="mw-page-title-main">Cardiopulmonary resuscitation</span> Emergency procedure for cardiac arrest

Cardiopulmonary resuscitation (CPR) is an emergency procedure consisting of chest compressions often combined with artificial ventilation, or mouth to mouth in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person who is in cardiac arrest. It is recommended for those who are unresponsive with no breathing or abnormal breathing, for example, agonal respirations.

<span class="mw-page-title-main">Cardioversion</span> Abnormally fast heart rate or arrhythmia is converted to a normal rhythm using electricity

Cardioversion is a medical procedure by which an abnormally fast heart rate (tachycardia) or other cardiac arrhythmia is converted to a normal rhythm using electricity or drugs. Synchronized electrical cardioversion uses a therapeutic dose of electric current to the heart at a specific moment in the cardiac cycle, restoring the activity of the electrical conduction system of the heart. Pharmacologic cardioversion, also called chemical cardioversion, uses antiarrhythmia medication instead of an electrical shock.

<span class="mw-page-title-main">Advanced cardiac life support</span> Emergency medical care

Advanced cardiac life support, advanced cardiovascular life support (ACLS) refers to a set of clinical guidelines for the urgent and emergent treatment of life-threatening cardiovascular conditions that will cause or have caused cardiac arrest, using advanced medical procedures, medications, and techniques. ACLS expands on Basic Life Support (BLS) by adding recommendations on additional medication and advanced procedure use to the CPR guidelines that are fundamental and efficacious in BLS. ACLS is practiced by advanced medical providers including physicians, some nurses and paramedics; these providers are usually required to hold certifications in ACLS care.

<span class="mw-page-title-main">Defibrillation</span> Treatment for life-threatening cardiac arrhythmias

Defibrillation is a treatment for life-threatening cardiac arrhythmias, specifically ventricular fibrillation (V-Fib) and non-perfusing ventricular tachycardia (V-Tach). A defibrillator delivers a dose of electric current to the heart. Although not fully understood, this process depolarizes a large amount of the heart muscle, ending the arrhythmia. Subsequently, the body's natural pacemaker in the sinoatrial node of the heart is able to re-establish normal sinus rhythm. A heart which is in asystole (flatline) cannot be restarted by a defibrillator, but would be treated only by cardiopulmonary resuscitation (CPR) and medication. Like this asystole sometimes converts into a shockable rhythm, which can be treated by cardioversion or defibrillation.

<span class="mw-page-title-main">Ventricular fibrillation</span> Rapid quivering of the ventricles of the heart

Ventricular fibrillation is an abnormal heart rhythm in which the ventricles of the heart quiver. It is due to disorganized electrical activity. Ventricular fibrillation results in cardiac arrest with loss of consciousness and no pulse. This is followed by sudden cardiac death in the absence of treatment. Ventricular fibrillation is initially found in about 10% of people with cardiac arrest.

<span class="mw-page-title-main">Asystole</span> Medical condition of the heart

Asystole is the absence of ventricular contractions in the context of a lethal heart arrhythmia. Asystole is the most serious form of cardiac arrest and is usually irreversible. Also referred to as cardiac flatline, asystole is the state of total cessation of electrical activity from the heart, which means no tissue contraction from the heart muscle and therefore no blood flow to the rest of the body.

<span class="mw-page-title-main">Automated external defibrillator</span> Portable electronic medical device

An automated external defibrillator or automatic electronic defibrillator (AED) is a portable electronic device that automatically diagnoses the life-threatening cardiac arrhythmias of ventricular fibrillation (VF) and pulseless ventricular tachycardia, and is able to treat them through defibrillation, the application of electricity which stops the arrhythmia, allowing the heart to re-establish an effective rhythm.

<span class="mw-page-title-main">Ventricular tachycardia</span> Medical condition of the heart

Ventricular tachycardia is a fast heart rate arising from the lower chambers of the heart. Although a few seconds of VT may not result in permanent problems, longer periods are dangerous; and multiple episodes over a short period of time are referred to as an electrical storm. Short periods may occur without symptoms, or present with lightheadedness, palpitations, or chest pain. Ventricular tachycardia may result in ventricular fibrillation (VF) and turn into cardiac arrest. This conversion of the VT into VF is called the degeneration of the VT. It is found initially in about 7% of people in cardiac arrest.

Precordial thump is a medical procedure used in the treatment of ventricular fibrillation or pulseless ventricular tachycardia under certain conditions. The procedure has a very low success rate, but may be used in those with witnessed, monitored onset of one of the "shockable" cardiac rhythms if a defibrillator is not immediately available. It should not delay cardiopulmonary resuscitation (CPR) and defibrillation, nor should it be used in those with unwitnessed out-of-hospital cardiac arrest.

<span class="mw-page-title-main">Advanced life support</span> Life-saving protocols

Advanced Life Support (ALS) is a set of life saving protocols and skills that extend basic life support to further support the circulation and provide an open airway and adequate ventilation (breathing).

A flatline is an electrical time sequence measurement that shows no activity and therefore, when represented, shows a flat line instead of a moving one. It almost always refers to either a flatlined electrocardiogram, where the heart shows no electrical activity (asystole), or to a flat electroencephalogram, in which the brain shows no electrical activity. Both of these specific cases are involved in various definitions of death.

<span class="mw-page-title-main">ABC (medicine)</span> Initialism mnemonics

ABC and its variations are initialism mnemonics for essential steps used by both medical professionals and lay persons when dealing with a patient. In its original form it stands for Airway, Breathing, and Circulation. The protocol was originally developed as a memory aid for rescuers performing cardiopulmonary resuscitation, and the most widely known use of the initialism is in the care of the unconscious or unresponsive patient, although it is also used as a reminder of the priorities for assessment and treatment of patients in many acute medical and trauma situations, from first-aid to hospital medical treatment. Airway, breathing, and circulation are all vital for life, and each is required, in that order, for the next to be effective. Since its development, the mnemonic has been extended and modified to fit the different areas in which it is used, with different versions changing the meaning of letters or adding other letters.

Pediatric advanced life support (PALS) is a course offered by the American Heart Association (AHA) for health care providers who take care of children and infants in the emergency room, critical care and intensive care units in the hospital, and out of hospital. The course teaches healthcare providers how to assess injured and sick children and recognize and treat respiratory distress/failure, shock, cardiac arrest, and arrhythmias.

The following outline is provided as an overview of and topical guide to cardiology, the branch of medicine dealing with disorders of the human heart. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in cardiology are called cardiologists.

The Hs and Ts is a mnemonic used to aid in remembering the possible reversible causes of cardiac arrest. A variety of disease processes can lead to a cardiac arrest; however, they usually boil down to one or more of the "Hs and Ts".

<span class="mw-page-title-main">Arrhythmia</span> Group of medical conditions characterized by irregular heartbeat

Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia, and a resting heart rate that is too slow – below 60 beats per minute – is called bradycardia. Some types of arrhythmias have no symptoms. Symptoms, when present, may include palpitations or feeling a pause between heartbeats. In more serious cases, there may be lightheadedness, passing out, shortness of breath or chest pain. While most cases of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in sudden death.

Return of spontaneous circulation (ROSC) is the resumption of a sustained heart rhythm that perfuses the body after cardiac arrest. It is commonly associated with significant respiratory effort. Signs of return of spontaneous circulation include breathing, coughing, or movement and a palpable pulse or a measurable blood pressure. Someone is considered to have sustained return of spontaneous circulation when circulation persists and cardiopulmonary resuscitation has ceased for at least 20 consecutive minutes.

<span class="mw-page-title-main">Rearrest</span>

Rearrest is a phenomenon that involves the resumption of a lethal cardiac dysrhythmia after successful return of spontaneous circulation (ROSC) has been achieved during the course of resuscitation. Survival to hospital discharge rates are as low as 7% for cardiac arrest in general and although treatable, rearrest may worsen these survival chances. Rearrest commonly occurs in the out-of-hospital setting under the treatment of health care providers.

References

  1. Bergström, Mattias; Schmidbauer, Simon; Herlitz, Johan; Rawshani, Araz; Friberg, Hans (December 2018). "Pulseless electrical activity is associated with improved survival in out-of-hospital cardiac arrest with initial non-shockable rhythm". Resuscitation. 133: 147–152. doi:10.1016/j.resuscitation.2018.10.018. ISSN   1873-1570. PMID   30352246. S2CID   53025153.
  2. Norvik, A.; Unneland, E.; Bergum, D.; Buckler, D. G.; Bhardwaj, A.; Eftestøl, T.; Aramendi, E.; Nordseth, T.; Abella, B. S.; Kvaløy, J. T.; Skogvoll, E. (2022-07-01). "Pulseless electrical activity in in-hospital cardiac arrest – A crossroad for decisions". Resuscitation. 176: 117–124. doi:10.1016/j.resuscitation.2022.04.024. hdl: 10810/57896 . ISSN   0300-9572. PMID   35490937.
  3. 1 2 3 4 5 6 7 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care (November 2010). "Part 8: Adult Advanced Cardiovascular Life Support". Circulation. 122 (18 Suppl): S729–S767. doi: 10.1161/CIRCULATIONAHA.110.970988 . PMID   20956224.
  4. Baldzizhar, A; Manuylova, E; Marchenko, R; Kryvalap, Y; Carey, MG (September 2016). "Ventricular Tachycardias: Characteristics and Management". Critical Care Nursing Clinics of North America. 28 (3): 317–29. doi:10.1016/j.cnc.2016.04.004. PMID   27484660.
  5. Mazur, Glen (2003). Acls: Principles And Practice. [Dallas, TX]: Amer Heart Assn. pp. 71–87. ISBN   0-87493-341-2.
  6. Barnes, Thomas Garden; Cummins, Richard O.; Field, John; Hazinski, Mary Fran (2003). ACLS for experienced providers . [Dallas, TX]: American Heart Association. pp.  3–5. ISBN   0-87493-424-9.
  7. 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care (December 2005). "Part 7.2: Management of Cardiac Arrest". Circulation. 112 (24 Suppl): IV 58–66. doi: 10.1161/CIRCULATIONAHA.105.166557 .