Cardiac Arrest Overview and Causes

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Questions and Answers

What is the primary electrical disturbance responsible for most cases of cardiac arrest?

Atrial Fibrillation

Ventricular Tachycardia

Ventricular Fibrillation (correct)

Electromechanical Dissociation

Which of the following symptoms is NOT typically associated with sudden cardiac arrest?

Loss of consciousness

Sweating profusely (correct)

No breathing

Sudden collapse

What is a significant consequence of global ischemia produced by cardiac arrest?

Hypotension

Bradycardia

Hypertension

Increased intracranial pressure (correct)

Which test records the heart's electrical activity to detect various heart problems?

EKG (Electrocardiogram) Signup and view all the answers

What is a direct consequence of decreased ATP production following cardiac arrest?

Loss of membrane integrity Signup and view all the answers

Which of the following findings on a physical examination is NOT indicative of cardiac arrest?

Fever Signup and view all the answers

How does excess calcium affect cells after resuscitation from cardiac arrest?

It leads to cellular edema. Signup and view all the answers

What condition is characterized by erratic electrical impulses leading to ineffective heart pumping?

Ventricular Fibrillation Signup and view all the answers

What role does an echocardiogram play in assessing cardiac function?

Creates images of the heart using sound waves. Signup and view all the answers

What is a common initial clinical finding during cardiac arrest?

No pulse Signup and view all the answers

What does stress echocardiography primarily assess?

The contraction and blood flow of the heart Signup and view all the answers

Which of the following statements about cardiac MRI is true?

It employs radio waves and magnets for imaging. Signup and view all the answers

What is the primary purpose of cardiac catheterization?

To diagnose and treat heart conditions Signup and view all the answers

Which of the following drugs is administered during cardiac arrest to correct acidosis?

Sodium bicarbonate Signup and view all the answers

What function does an implantable cardioverter defibrillator (ICD) serve?

To reduce the risk of sudden cardiac arrest recurrence Signup and view all the answers

What characteristic is associated with the administration of epinephrine in emergency cardiac situations?

It enhances conductivity and contractility Signup and view all the answers

What initial assessment does the CPR method emphasize in the airway management?

Look, listen, and feel Signup and view all the answers

Which of these procedures does NOT involve imaging of the heart?

Medical management with drug therapy Signup and view all the answers

What is the role of calcium chloride in cardiac treatment?

To enhance myocardial contractile force Signup and view all the answers

What does the catheter in a cardiac catheterization procedure allow doctors to do?

Inject a special dye for imaging Signup and view all the answers

What is a common effect of global ischemia on cells during cardiac arrest?

Direct cellular damage Signup and view all the answers

Which symptom is typically associated with cardiac arrest?

Loss of consciousness Signup and view all the answers

Which of the following describes the primary function of an echocardiogram?

To create pictures of the heart Signup and view all the answers

What can be detected through a cardiac MRI?

The structure and function of the heart Signup and view all the answers

What is a common cause of sudden cardiac arrest?

Hyperkalemia Signup and view all the answers

What is the primary focus of an EKG/ECG test?

Recording heart's electrical activity Signup and view all the answers

Which physiological change occurs as a direct result of cardiac arrest?

Decreased blood circulation Signup and view all the answers

What phenomenon occurs in the heart during ventricular fibrillation?

Erratic electrical impulses Signup and view all the answers

What is the primary function of the dye injected during cardiac catheterization?

To visualize internal structures of the heart Signup and view all the answers

Which of the following actions is NOT part of the current resuscitation protocol recommendations for sudden cardiac arrest?

Administration of high doses of nitroglycerin Signup and view all the answers

What is the main purpose of an implantable cardioverter defibrillator (ICD) for someone who has survived sudden cardiac arrest?

To reduce the chances of dying from a second SCA Signup and view all the answers

In the context of managing arrest caused by ventricular fibrillation, what should be done first if initial interventions fail?

Initiate immediate CPR Signup and view all the answers

Which class of drugs is commonly administered during cardiac emergencies to support heart rhythm?

Antiarrhythmics Signup and view all the answers

Study Notes

Cardiac Arrest

Cardiac arrest is a sudden, unexpected loss of heart function, breathing, and consciousness.
It typically results from an electrical disturbance in the heart.
This disturbance disrupts the heart's pumping action, stopping blood flow to the rest of the body.

Causes of Cardiac Arrest

Ventricular Fibrillation: The most common cause. It's an arrhythmia where rapid, erratic electrical impulses cause the ventricles to quiver uselessly, preventing effective blood pumping.
Ventricular Tachycardia: Rapid heartbeat of the ventricles.
Electromechanical Dissociation: A disconnect between the electrical and mechanical activity of the heart.

Symptoms of Cardiac Arrest

Sudden collapse
No pulse
No breathing
Loss of consciousness
Pale, ashen gray skin
Bluish discoloration (cyanosis)
Dilated pupils
Absence of blood pressure (BP)

Pathophysiology of Cardiac Arrest

Cardiac arrest causes global ischemia (lack of blood flow) at the cellular level.
This leads to cellular damage and edema (fluid buildup), particularly damaging the brain due to limited space for expansion.
Increased intracranial pressure results from edema, negatively impacting cerebral perfusion.
Resuscitated patients may experience short or long-term cerebral dysfunction.
Reduced ATP (energy) production leads to loss of membrane integrity and electrolyte imbalances (Na, K, Ca).
This can cause cellular edema and damage to mitochondria, decreasing ATP production further.
Free radical formation and protease activation also occur, damaging cellular contents.

Cardiac Arrest vs. Heart Attack

Cardiac arrest is an electrical problem, where rapid, unusual heartbeats override the normal rhythm;
Heart attack is a problem of blood flow disruption caused by a blocked artery, preventing blood reaching the heart muscle.
A heart attack can sometimes lead to cardiac arrest.

Diagnostic Tests and Procedures

EKG (Electrocardiogram): A painless test that records the heart's electrical activity to detect heart abnormalities.
Echocardiography: A painless procedure that uses sound waves to create images of the heart. This allows doctors to assess the heart's structure and function, and if the heart muscle cannot contract normally.
Stress echocardiography assesses whether blood flow to the heart diminishes under stress.
Cardiac Magnetic Resonance Imaging (MRI): A safe test that uses radio waves and magnets to create detailed images of the heart, capturing the heart's beat and blood vessels.

Cardiac Catheterization

A procedure used to diagnose and treat heart issues.
A catheter is inserted into a blood vessel, reaching the heart for diagnostic or therapeutic activities.
Special dye may be injected to visualize heart structures and blood vessels using X-rays.

Medical Management (Cardiopulmonary Resuscitation)

Airway: Assessment and maintenance of a free airway (look, listen, feel).
Breathing: Resuscitation techniques to restore breathing.
Circulation: Chest compressions to revive blood flow.

Drug Therapy for Cardiac Arrest

Medications like lidocaine, procainamide, and verapamil for arrhythmia management are frequently used.
Dopamine and isoproterenol aid in enhancing heart function.
Epinephrine is used to boost myocardial function (contractility, excitability, and conductivity).
Atrophine sulfate can increase heart rate.
Sodium bicarbonate may be administered to correct metabolic acidosis.
Calcium chloride can improve myocardial contraction.
Defibrillation is an electric shock to restore a normal heart rhythm.

For People Surviving Sudden Cardiac Arrest

Individuals who have survived SCA are at high risk for recurrence.
An implantable cardioverter-defibrillator (ICD) is often implanted to reduce the chance of a second SCA.
An ICD is surgically placed under the skin, connected to the heart by wires to detect potentially dangerous arrhythmias.
If an abnormal heart rhythm is detected, the ICD delivers an electric shock to correct the pattern.

Nursing Interventions

Monitor arrest caused by ventricular fibrillation.
Initial treatment involves precordial thump, followed by lidocaine if successful; otherwise, defibrillation is attempted.
If defibrillation fails, cardiopulmonary resuscitation (CPR) is initiated.
Assist in administering and monitoring further emergency medications.

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Description

This quiz covers key concepts about cardiac arrest, including its definition, causes, symptoms, and pathophysiology. Understanding these elements is crucial for recognizing cardiac emergencies and responding effectively. Test your knowledge and learn about this critical medical condition.