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Cardiac Arrest

Cardiac arrest is the sudden, complete cessation of cardiac output Cardiac output The volume of blood passing through the heart per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with stroke volume (volume per beat). Cardiac Mechanics with hemodynamic collapse. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present as pulseless, unresponsive, and apneic. Rhythms associated with cardiac arrest are ventricular fibrillation Ventricular fibrillation Ventricular fibrillation (VF or V-fib) is a type of ventricular tachyarrhythmia (> 300/min) often preceded by ventricular tachycardia. In this arrhythmia, the ventricle beats rapidly and sporadically. The ventricular contraction is uncoordinated, leading to a decrease in cardiac output and immediate hemodynamic collapse. Ventricular Fibrillation (V-fib)/ tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children, asystole, or pulseless electrical activity. The treatment of cardiac arrest begins with basic life support Basic Life Support Airway Management ( BLS BLS Airway Management) when out-of-hospital and advanced cardiac life support (ACLS) when in-hospital. Basic life support Basic Life Support Airway Management comprises checking the patient’s mental status, activating the emergency response system, and cardiopulmonary resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome (CPR). An automated external defibrillator ( AED AED Cardiac electrical stimulators that apply brief high-voltage electroshocks to the heart. These stimulators are used to restore normal rhythm and contractile function in hearts of patients who are experiencing ventricular fibrillation or ventricular tachycardia that is not accompanied by a palpable pulse. Some defibrillators may also be used to correct certain noncritical dysrhythmias (called synchronized defibrillation or cardioversion), using relatively low-level discharges synchronized to the patient's ECG waveform. Cardiopulmonary Resuscitation (CPR)) should be used once available. High-quality CPR (with early defibrillation Defibrillation Ventricular Fibrillation (V-fib) in shockable rhythms) is crucial to survival in cardiac arrest. Advanced cardiac life support includes CPR, securing the airway Airway ABCDE Assessment, administering medications (such as epinephrine Epinephrine The active sympathomimetic hormone from the adrenal medulla. It stimulates both the alpha- and beta- adrenergic systems, causes systemic vasoconstriction and gastrointestinal relaxation, stimulates the heart, and dilates bronchi and cerebral vessels. Sympathomimetic Drugs), and identifying and treatment of the cause of cardiac arrest. Post-cardiac arrest care follows return of spontaneous circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment (ROSC).

Last updated: Apr 11, 2023

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Definition

Sudden cardiac arrest (SCA) is the abrupt cessation of cardiac activity.

Epidemiology

  • Approximately 350,000 SCAs per year occur in the United States.
    • 60% occur out-of-hospital, with a 10% survival rate (up to 30% when witnessed by a bystander).
    • 40% occur in-hospital, with a 20% survival rate.
  • Incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency of cardiac arrest increases linearly with age.
  • 57% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are men.
  • Survival rate is 10% for non-shockable rhythms and > 30% for shockable rhythms.

Risk factors

  • Smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases 
  • Family history Family History Adult Health Maintenance of SCA
  • Heavy alcohol intake (6 or more drinks/day) or binge drinking
  • Elevated free fatty acids Acids Chemical compounds which yield hydrogen ions or protons when dissolved in water, whose hydrogen can be replaced by metals or basic radicals, or which react with bases to form salts and water (neutralization). An extension of the term includes substances dissolved in media other than water. Acid-Base Balance (associated with sudden cardiac death ( SCD SCD Sickle cell disease (SCD) is a group of genetic disorders in which an abnormal Hb molecule (HbS) transforms RBCs into sickle-shaped cells, resulting in chronic anemia, vasoocclusive episodes, pain, and organ damage. Sickle Cell Disease) and ventricular arrhythmia after a myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction)

Etiology and Clinical Presentation

Cardiac causes of cardiac arrest

  • Structural heart disease: 
    • Coronary heart disease Coronary heart disease Coronary heart disease (CHD), or ischemic heart disease, describes a situation in which an inadequate supply of blood to the myocardium exists due to a stenosis of the coronary arteries, typically from atherosclerosis. Coronary Heart Disease (CHD): associated with up to 70% of SCAs
    • Congenital Congenital Chorioretinitis heart diseases
    • Cardiomyopathies Cardiomyopathies A group of diseases in which the dominant feature is the involvement of the cardiac muscle itself. Cardiomyopathies are classified according to their predominant pathophysiological features (dilated cardiomyopathy; hypertrophic cardiomyopathy; restrictive cardiomyopathy) or their etiological/pathological factors (cardiomyopathy, alcoholic; endocardial fibroelastosis). Cardiomyopathy: Overview and Types
    • Valvular heart diseases
    • Myocarditis Myocarditis Myocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. There are numerous etiologies of myocarditis, but all lead to inflammation and myocyte injury, most often leading to signs and symptoms of heart failure. Myocarditis
    • Aortic dissection Aortic dissection Aortic dissection occurs due to shearing stress from pulsatile pressure causing a tear in the tunica intima of the aortic wall. This tear allows blood to flow into the media, creating a “false lumen.” Aortic dissection is most commonly caused by uncontrolled hypertension. Aortic Dissection
    • Acute pericardial tamponade Pericardial tamponade Compression of the heart by accumulated fluid (pericardial effusion) or blood (hemopericardium) in the pericardium surrounding the heart. The affected cardiac functions and cardiac output can range from minimal to total hemodynamic collapse. Penetrating Chest Injury
  • No structural heart disease:
    • Complete heart block
    • Brugada syndrome Brugada syndrome An autosomal dominant defect of cardiac conduction that is characterized by an abnormal st-segment in leads v1-v3 on the electrocardiogram resembling a right bundle-branch block; high risk of ventricular tachycardia; or ventricular fibrillation; syncopal episode; and possible sudden death. This syndrome is linked to mutations of gene encoding the cardiac sodium channel alpha subunit. Ventricular Tachycardia
    • Idiopathic Idiopathic Dermatomyositis ventricular fibrillation Ventricular fibrillation Ventricular fibrillation (VF or V-fib) is a type of ventricular tachyarrhythmia (> 300/min) often preceded by ventricular tachycardia. In this arrhythmia, the ventricle beats rapidly and sporadically. The ventricular contraction is uncoordinated, leading to a decrease in cardiac output and immediate hemodynamic collapse. Ventricular Fibrillation (V-fib)
    • Long QT syndrome Long QT syndrome Long QT syndrome (LQTS) is a disorder of ventricular myocardial repolarization that produces QT prolongation on electrocardiogram (ECG). Long QT syndrome is associated with an increased risk of developing life-threatening cardiac arrhythmias, specifically torsades de pointes. Long QT Syndrome
    • Preexcitation syndrome
    • Familial sudden cardiac death
    • Chest wall Chest wall The chest wall consists of skin, fat, muscles, bones, and cartilage. The bony structure of the chest wall is composed of the ribs, sternum, and thoracic vertebrae. The chest wall serves as armor for the vital intrathoracic organs and provides the stability necessary for the movement of the shoulders and arms. Chest Wall: Anatomy trauma ( commotio cordis Commotio cordis A sudden cardiac arrhythmia (e.g., ventricular fibrillation) caused by a blunt, non-penetrating impact to the precordial region of chest wall. Commotio cordis often results in sudden death without prompt cardiopulmonary defibrillation. Blunt Chest Trauma)

Non-cardiac causes of cardiac arrest

  • Trauma
  • Electrocution 
  • Excessive hemorrhage
  • Hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia
  • Pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism
  • Drowning Drowning Drowning occurs due to respiratory impairment from submersion or immersion in a liquid medium. Aspiration of water leads to hypoxemia, which affects all organ systems, resulting in respiratory insufficiency and acute respiratory distress syndrome (ARDS), cardiac arrhythmias, and neuronal damage. Drowning
  • Sudden infant death syndrome Sudden Infant Death Syndrome Sudden infant death syndrome (SIDS) describes the sudden death of an otherwise healthy infant (< 1 year of age) with no identifiable cause. Sudden infant death syndrome is the leading cause of death in children between 1 and 12 months of age in the United States. Sudden Infant Death Syndrome (SIDS) ( SIDS SIDS Sudden infant death syndrome (SIDS) describes the sudden death of an otherwise healthy infant (< 1 year of age) with no identifiable cause. Sudden infant death syndrome is the leading cause of death in children between 1 and 12 months of age in the United States. Sudden Infant Death Syndrome (SIDS))
  • Sudden unexplained death Unexplained Death Sudden Infant Death Syndrome (SIDS) in epilepsy Epilepsy Epilepsy is a chronic brain disorder marked by recurrent and unprovoked seizures. These seizures can be classified as focal or generalized and idiopathic or secondary to another condition. Clinical presentation correlates to the classification of the epileptic disorder. Epilepsy (SUDEP)

Mnemonics

The 5 Hs HS Hypertrophic scars and keloids are raised, red, and rigid (3 rs) scars that develop during cutaneous wound healing and are characterized by a local abnormal proliferation of fibroblasts with over-production of collagen. Over-expression of growth factors and decreased production of molecules that promote matrix breakdown appear to be involved in the etiology. Hypertrophic and Keloid Scars and 5 Ts of the common reversible causes of SCA:

  • 5 Hs:
    1. Hypoxia Hypoxia Sub-optimal oxygen levels in the ambient air of living organisms. Ischemic Cell Damage
    2. Hypovolemia Hypovolemia Sepsis in Children
    3. Hypokalemia Hypokalemia Hypokalemia is defined as plasma potassium (K+) concentration < 3.5 mEq/L. Homeostatic mechanisms maintain plasma concentration between 3.5-5.2 mEq/L despite marked variation in dietary intake. Hypokalemia can be due to renal losses, GI losses, transcellular shifts, or poor dietary intake. Hypokalemia or hyperkalemia Hyperkalemia Hyperkalemia is defined as a serum potassium (K+) concentration >5.2 mEq/L. Homeostatic mechanisms maintain the serum K+ concentration between 3.5 and 5.2 mEq/L, despite marked variation in dietary intake. Hyperkalemia can be due to a variety of causes, which include transcellular shifts, tissue breakdown, inadequate renal excretion, and drugs. Hyperkalemia
    4. Hypothermia Hypothermia Hypothermia can be defined as a drop in the core body temperature below 35°C (95°F) and is classified into mild, moderate, severe, and profound forms based on the degree of temperature decrease. Hypothermia
    5. Hydrogen ion ( acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis)
  • 5 Ts:
    1. Toxins
    2. Tamponade Tamponade Pericardial effusion, usually of rapid onset, exceeding ventricular filling pressures and causing collapse of the heart with a markedly reduced cardiac output. Pericarditis
    3. Tension pneumothorax Tension Pneumothorax Pneumothorax
    4. Thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus ( myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction)
    5. Thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus ( pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism)

Clinical presentation

  • Unresponsive (loss of consciousness)
  • Pulseless
  • Apneic (may have agonal respirations)
  • Some have warning symptoms
    • Most common symptoms:
      • Chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
      • Dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea
    • Up to 80% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship have symptoms 1 hour before and 50% have symptoms 1 month before the SCA.

Cardiac Rhythms

Four major cardiac rhythms are associated with SCA. These rhythms are divided into shockable and non-shockable rhythms.

Shockable rhythms

Shockable rhythms are usually caused by primary cardiac disease (most commonly ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage). Less commonly, they are caused by systemic conditions (electrolyte disturbances, toxins, autoimmunity Autoimmunity Autoimmunity is a pathologic immune response toward self-antigens, resulting from a combination of factors: immunologic, genetic, and environmental. The immune system is equipped with self-tolerance, allowing immune cells such as T cells and B cells to recognize self-antigens and to not mount a reaction against them. Defects in this mechanism, along with environmental triggers (such as infections) and genetic susceptibility factors (most notable of which are the HLA genes) can lead to autoimmune diseases. Autoimmunity).

  • Ventricular fibrillation Ventricular fibrillation Ventricular fibrillation (VF or V-fib) is a type of ventricular tachyarrhythmia (> 300/min) often preceded by ventricular tachycardia. In this arrhythmia, the ventricle beats rapidly and sporadically. The ventricular contraction is uncoordinated, leading to a decrease in cardiac output and immediate hemodynamic collapse. Ventricular Fibrillation (V-fib) ( VF VF Ventricular fibrillation (VF or V-fib) is a type of ventricular tachyarrhythmia (> 300/min) often preceded by ventricular tachycardia. In this arrhythmia, the ventricle beats rapidly and sporadically. The ventricular contraction is uncoordinated, leading to a decrease in cardiac output and immediate hemodynamic collapse. Ventricular Fibrillation (V-fib)):
    • Disorganized high-frequency electrical activity in the ventricles
    • No mechanical contraction, which means no pulse
  • Pulseless ventricular tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children ( VT VT Ventricular tachycardia is any heart rhythm faster than 100 beats/min, with 3 or more irregular beats in a row, arising distal to the bundle of his. Ventricular tachycardia is the most common form of wide-complex tachycardia, and it is associated with a high mortality rate. Ventricular Tachycardia):

Non-shockable rhythms

  • Asystole:
    • No discernible electrical activity
    • Flatline on electrocardiogram Electrocardiogram An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) (P waves and QRS complexes are not present)
  • Pulseless electrical activity (PEA):
    • Electrocardiogram Electrocardiogram An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) ( ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG)) shows a cardiac rhythm without a palpable pulse.
    • May be organized (with normal-appearing ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) complexes) or unorganized (no discernible complexes on ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG))
    • From electromechanical dissociation Dissociation Defense Mechanisms, or no cardiac filling (“empty heart”)

Management with Basic Life Support (BLS)

Chain of survival

  1. Recognize an arrest and confirm scene safety.
    • Attempt to rouse the patient verbally and physically.
    • Observe for signs of breathing ( patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship may have agonal breathing Agonal Breathing ABCDE Assessment in cardiac arrest).
    • Check the patient’s pulse within 10 seconds:
  2. Activate the emergency response system.
    • Call for help/call other people for assistance.
    • Call 911.
    • Have someone get an automated external defibrillator ( AED AED Cardiac electrical stimulators that apply brief high-voltage electroshocks to the heart. These stimulators are used to restore normal rhythm and contractile function in hearts of patients who are experiencing ventricular fibrillation or ventricular tachycardia that is not accompanied by a palpable pulse. Some defibrillators may also be used to correct certain noncritical dysrhythmias (called synchronized defibrillation or cardioversion), using relatively low-level discharges synchronized to the patient’s ECG waveform. Cardiopulmonary Resuscitation (CPR)), if available.
  3. Start cardiopulmonary resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome (CPR) immediately.
    • Ideally done simultaneously with calling for help
    • Important addition: If opioid Opioid Compounds with activity like opiate alkaloids, acting at opioid receptors. Properties include induction of analgesia or narcosis. Constipation overdose is suspected, give naloxone Naloxone A specific opiate antagonist that has no agonist activity. It is a competitive antagonist at mu, delta, and kappa opioid receptors. Opioid Analgesics if available.
  4. Check the cardiac rhythm with an AED AED Cardiac electrical stimulators that apply brief high-voltage electroshocks to the heart. These stimulators are used to restore normal rhythm and contractile function in hearts of patients who are experiencing ventricular fibrillation or ventricular tachycardia that is not accompanied by a palpable pulse. Some defibrillators may also be used to correct certain noncritical dysrhythmias (called synchronized defibrillation or cardioversion), using relatively low-level discharges synchronized to the patient’s ECG waveform. Cardiopulmonary Resuscitation (CPR) once it arrives.
  5. When shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock is indicated, continue chest compressions Chest Compressions Cardiopulmonary Resuscitation (CPR) until just before shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock is ready to be given.
  6. Resume chest compressions Chest Compressions Cardiopulmonary Resuscitation (CPR) immediately after delivery of shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock, continuing until emergency responders are available.

High-quality CPR

General cardiopulmonary resuscitation (cpr) cycle

General CPR cycle: (start: bottom image)
1. Upon recognition of cardiac arrest, give 30 firm chest compressions.
2. Follow the compressions with 2 rescue breaths.
3. When an AED arrives, place pads in appropriate areas.
4. When prompted by the AED, check rhythm and deliver the shock when indicated (after making sure that no one is in physical contact with the patient).
Resume CPR cycle after shock delivery.

Image: “Aed ablauf” by Jörg Rittmeister. License: Public Domain

Management with Advanced Cardiac Life Support (ACLS)

Circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment, airway Airway ABCDE Assessment, breath (CAB)

Circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment, airway Airway ABCDE Assessment, breath is the advanced cardiac life support mantra. Since 2010, management has focused on starting chest compressions Chest Compressions Cardiopulmonary Resuscitation (CPR) first to address circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment, then airway Airway ABCDE Assessment access and rescue breathing Rescue Breathing Drowning.

  • C ( circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment):
    • High-quality CPR
    • Determine rhythm; in PEA/asystole, continue CPR.
    • Defibrillate shockable rhythms:
      • Shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock at 120–200 joules on a biphasic defibrillator (lower peak electric current efficient in terminating ventricular tachyarrhythmias).
      • Shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock at 360 joules on a monophasic defibrillator. 
    • Establish intravenous (IV) or intraosseous (IO) access.
    • Epinephrine Epinephrine The active sympathomimetic hormone from the adrenal medulla. It stimulates both the alpha- and beta- adrenergic systems, causes systemic vasoconstriction and gastrointestinal relaxation, stimulates the heart, and dilates bronchi and cerebral vessels. Sympathomimetic Drugs 1 mg IV and repeat every 3–5 minutes for all rhythms.
    • Medications for shockable rhythms (ventricular tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children/fibrillation):
      • Amiodarone Amiodarone An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting potassium channels and voltage-gated sodium channels. There is a resulting decrease in heart rate and in vascular resistance. Pulmonary Fibrosis 300 mg IV with repeat dose of 150 mg IV as indicated
      • Consider lidocaine Lidocaine A local anesthetic and cardiac depressant used as an antiarrhythmic agent. Its actions are more intense and its effects more prolonged than those of procaine but its duration of action is shorter than that of bupivacaine or prilocaine. Local Anesthetics.
      • For torsades de pointes Torsades de pointes A malignant form of polymorphic ventricular tachycardia that is characterized by heart rate between 200 and 250 beats per minute, and QRS complexes with changing amplitude and twisting of the points. The term also describes the syndrome of tachycardia with prolonged ventricular repolarization, long qt intervals exceeding 500 milliseconds or bradycardia. Torsades de pointes may be self-limited or may progress to ventricular fibrillation. Ventricular Tachycardia: magnesium sulfate Magnesium Sulfate A small colorless crystal used as an anticonvulsant, a cathartic, and an electrolyte replenisher in the treatment of pre-eclampsia and eclampsia. It causes direct inhibition of action potentials in myometrial muscle cells. Excitation and contraction are uncoupled, which decreases the frequency and force of contractions. Laxatives (not for routine use)
  • A ( airway Airway ABCDE Assessment): 
    • Bag-mask device (if not intubated)
    • Use of an advanced airway Airway ABCDE Assessment (endotracheal tube or ETT): 10/min
  • B (breathing): 
    • Oxygenate patient with 100% oxygen 100% Oxygen Cluster Headaches.
    • Use quantitative waveform capnography (check end-tidal (ETCO₂)): If ETCO₂ is low or decreasing, check CPR quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement.
  • Differential diagnosis: 5 Hs HS Hypertrophic scars and keloids are raised, red, and rigid (3 rs) scars that develop during cutaneous wound healing and are characterized by a local abnormal proliferation of fibroblasts with over-production of collagen. Over-expression of growth factors and decreased production of molecules that promote matrix breakdown appear to be involved in the etiology. Hypertrophic and Keloid Scars and 5 Ts; treat accordingly
Adult cardiac arrest diagram

Adult cardiac arrest diagram
Upon recognition of cardiac arrest, rapid evaluation of breathing, pulse and rhythm (once cardiac monitor is available) is done and cardiopulmonary resuscitation (CPR) is initiated. Defibrillate shockable rhythms, ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). If with pulseless electrical activity/asystole, CPR continues. Simultaneously through the process, intravenous (IV) access (or intraosseous access) is obtained to administer needed medications. IV epinephrine is given every 3–5 minutes.
Endotracheal intubation (advanced airway) is performed. Quantitative waveform capnography (which shows end-tidal (et)CO₂) is monitored. If (et)CO₂ is low, reassess CPR quality.
Cycle of steps (defibrillation and/or CPR with minimal interruption + airway support → rhythm, pulse and blood pressure check → IV medication administration) continues until return of spontaneous circulation (ROSC). Continuation of the cycle is also assessed if there is no ROSC. Signs of ROSC are: pulse and blood pressure present, abrupt sustained increase in etCO₂ (about ≥ 40 mm Hg) and spontaneous arterial pressure waves with intra-arterial monitoring.

Image by Lecturio.

Special populations

  • Pediatric advanced life support ( PALS PALS Secondary Lymphatic Organs): 
    • In asystole/PEA, administer epinephrine Epinephrine The active sympathomimetic hormone from the adrenal medulla. It stimulates both the alpha- and beta- adrenergic systems, causes systemic vasoconstriction and gastrointestinal relaxation, stimulates the heart, and dilates bronchi and cerebral vessels. Sympathomimetic Drugs as soon as possible (within 5 min).
    • Use cuffed ETT to reduce air leaks.
    • Respiratory rate Respiratory rate The number of times an organism breathes with the lungs (respiration) per unit time, usually per minute. Pulmonary Examination increased to 20–30/min
    • Medications and shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock energy are given based on weight.
  • Pregnant patient in-hospital ACLS:
    • More prone to hypoxia Hypoxia Sub-optimal oxygen levels in the ambient air of living organisms. Ischemic Cell Damage: oxygenation and airway Airway ABCDE Assessment management prioritized during resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome from cardiac arrest 
    • Adult ACLS + IV placement above the diaphragm Diaphragm The diaphragm is a large, dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. The diaphragm consists of muscle fibers and a large central tendon, which is divided into right and left parts. As the primary muscle of inspiration, the diaphragm contributes 75% of the total inspiratory muscle force. Diaphragm: Anatomy (ensures the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy does not obstruct IV administration)
    • If receiving IV magnesium Magnesium A metallic element that has the atomic symbol mg, atomic number 12, and atomic weight 24. 31. It is important for the activity of many enzymes, especially those involved in oxidative phosphorylation. Electrolytes: Stop and give calcium chloride Calcium chloride A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning. Hypocalcemia or gluconate.
    • Provide lateral uterine displacement Displacement The process by which an emotional or behavioral response that is appropriate for one situation appears in another situation for which it is inappropriate. Defense Mechanisms to relieve aortocaval compression Compression Blunt Chest Trauma.
    • Obstetric and neonatal care:
      • If no ROSC in 5 minutes: immediate perimortem cesarean delivery Cesarean Delivery Cesarean delivery (CD) is the operative delivery of ≥ 1 infants through a surgical incision in the maternal abdomen and uterus. Cesarean deliveries may be indicated for a number of either maternal or fetal reasons, most commonly including fetal intolerance to labor, arrest of labor, a history of prior uterine surgery, fetal malpresentation, and placental abnormalities. Cesarean Delivery
      • Neonatal team to receive neonate Neonate An infant during the first 28 days after birth. Physical Examination of the Newborn
    • Consider etiologies of maternal cardiac arrest (A, B, C, D, E, F, G, H):
      • Anesthetic complications
      • Bleeding
      • Cardiovascular
      • Drugs
      • Embolic
      • Fever
      • General nonobstetric causes (5 Hs HS Hypertrophic scars and keloids are raised, red, and rigid (3 rs) scars that develop during cutaneous wound healing and are characterized by a local abnormal proliferation of fibroblasts with over-production of collagen. Over-expression of growth factors and decreased production of molecules that promote matrix breakdown appear to be involved in the etiology. Hypertrophic and Keloid Scars and 5 Ts)
      • Hypertension
  • Coronavirus disease 2019 Coronavirus disease 2019 Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that mainly affects the respiratory system but can also cause damage to other body systems (cardiovascular, gastrointestinal, renal, and central nervous systems). ( COVID-19 COVID-19 Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that mainly affects the respiratory system but can also cause damage to other body systems (cardiovascular, gastrointestinal, renal, and central nervous systems). ):
    • Whenever possible, patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are placed in negative pressure rooms.
    • Don appropriate personal protective equipment Personal protective equipment Specialized clothing or equipment worn for protection against health hazards. Personal protective equipment may include masks; respiratory protective devices; head protective devices; eye protective devices; ear protective devices; protective clothing; and protective footwear. Leptospira/Leptospirosis (PPE) prior to entry.
    • Limit Limit A value (e.g., pressure or time) that should not be exceeded and which is specified by the operator to protect the lung Invasive Mechanical Ventilation personnel performing CPR.
    • Oxygenation, preferably with low aerosolization risk
    • Pause chest compression Chest Compression Crush Syndrome for endotracheal intubation Intubation Peritonsillar Abscess.
    • When possible, connect patient to a ventilator with inline HEPA (high-efficiency particulate air) filter.

Outcomes

Return of spontaneous circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment signs

  • Pulse and blood pressure
  • Abrupt sustained increase in ETCO₂ level (about ≥ 40 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg)
  • Spontaneous arterial pressure waves with intra-arterial monitoring

Criteria for termination of resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome:

  • Several factors considered in making the decision to stop:
    • Duration of resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome (> 30 minutes without perfusing rhythm)
    • Initial rhythm: asystole
    • Absence of brainstem function
    • Long interval between arrest and resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome
    • Patient age and comorbidities Comorbidities The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival. St. Louis Encephalitis Virus
    • Normothermia
  • In out-of-hospital resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome, the criteria are:
    • Arrest not witnessed by emergency medical services (EMS)
    • Asystole/PEA (no shocks delivered)
    • No ROSC before the 3rd dose of epinephrine Epinephrine The active sympathomimetic hormone from the adrenal medulla. It stimulates both the alpha- and beta- adrenergic systems, causes systemic vasoconstriction and gastrointestinal relaxation, stimulates the heart, and dilates bronchi and cerebral vessels. Sympathomimetic Drugs
  • ETCO₂ level:
    • Indicates CO₂ production, which increases with perfusion and pulmonary circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment (↑ in ROSC)
    • When low, confirm endotracheal tube placement Tube placement Surgical procedure involving the creation of an opening (stoma) into the chest cavity for drainage; used in the treatment of pleural effusion; pneumothorax; hemothorax; and empyema. Thoracic Surgery first.  
    • A confirmed low EtCO₂ (< 10 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg) in > 20 min of resuscitation Resuscitation The restoration to life or consciousness of one apparently dead. . Neonatal Respiratory Distress Syndrome: absent circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment and predicts acute mortality Mortality All deaths reported in a given population. Measures of Health Status

Post-resuscitation Care

Goals

  • Brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification injury mitigation
  • Manage ischemia-reperfusion injury and support multi-organ systems.
  • Determine and treat cause of SCA.
  • Involve a multidisciplinary medical team given complexity of post-arrest patient care.

Critical care

  • Hemodynamic support:
    • Use of crystalloid Crystalloid Isotonic solutions of mineral salts, such as ringer’s lactate and sodium chloride (saline solution), used in fluid therapy to rehydrate blood volume. Intravenous Fluids and/or vasopressor Vasopressor Acute Cholangitis or inotropic support
    • Maintain systolic blood pressure > 90 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg or mean arterial pressure Mean Arterial Pressure Mean arterial pressure (MAP) is the average systemic arterial pressure and is directly related to cardiac output (CO) and systemic vascular resistance (SVR). The SVR and MAP are affected by the vascular anatomy as well as a number of local and neurohumoral factors. Vascular Resistance, Flow, and Mean Arterial Pressure > 65 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg.
    • Emergent cardiac intervention in cases of ST-segment elevation myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction and/or cardiogenic shock Cardiogenic shock Shock resulting from diminution of cardiac output in heart disease. Types of Shock
  • Mechanical ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing:
    • Titrate fraction of inspired oxygen (FiO2) for oxygen saturation Oxygen Saturation Basic Procedures (SPO2) > 94%.
    • Titrate to partial pressure Partial pressure The pressure that would be exerted by one component of a mixture of gases if it were present alone in a container. Gas Exchange of carbon dioxide (PaCO2) 35–45 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg.
    • Start at 10/min.
  • Targeted temperature management for comatose Comatose A profound state of unconsciousness associated with depressed cerebral activity from which the individual cannot be aroused. Coma generally occurs when there is dysfunction or injury involving both cerebral hemispheres or the brain stem reticular formation. Hyponatremia patient:
    • Improves neurologic outcome 
    • Use of cooling device with feedback loop, beginning at 32–36ºC (89.6–96.8ºF) for 24 hours
    • ↑ risk of death for each degree rise above 37ºC (98.6ºF)
  • Other critical care management:
    • Continuous temperature monitoring
    • Maintenance of normoxia and normocapnia
    • Lung-protective ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing
    • Maintenance of euglycemia ( insulin Insulin Insulin is a peptide hormone that is produced by the beta cells of the pancreas. Insulin plays a role in metabolic functions such as glucose uptake, glycolysis, glycogenesis, lipogenesis, and protein synthesis. Exogenous insulin may be needed for individuals with diabetes mellitus, in whom there is a deficiency in endogenous insulin or increased insulin resistance. Insulin therapy to maintain a blood glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance of 150–180 mg/dL)
    • Electroencephalogram ( EEG EEG Seizures) monitoring
  • Evaluation and treatment of causes:
    • Obtain brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification computed tomography (CT) scan
    • Other imaging studies depending on the clinical picture
    • Laboratory tests
    • Remember the 5 Hs HS Hypertrophic scars and keloids are raised, red, and rigid (3 rs) scars that develop during cutaneous wound healing and are characterized by a local abnormal proliferation of fibroblasts with over-production of collagen. Over-expression of growth factors and decreased production of molecules that promote matrix breakdown appear to be involved in the etiology. Hypertrophic and Keloid Scars and Ts.

Prevention

Primary prevention

  • Screen for risk factors for CHD ( lipid disorders Lipid disorders An abnormal amount of lipid in blood is called dyslipidemia, which includes abnormal levels of cholesterol, triglycerides, and/or lipoproteins. Dyslipidemia may be primary (familial) or secondary (acquired). Both primary and secondary causes can lead to the development of premature cardiovascular (atherosclerosis) disease. Lipid Disorders, hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension).
  • Screen for CHD (in appropriate patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship).
  • Reduce risk factors:
    • Control hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension.
    • Treat hypercholesterolemia Hypercholesterolemia A condition with abnormally high levels of cholesterol in the blood. It is defined as a cholesterol value exceeding the 95th percentile for the population. Lipid Disorders.
    • Treat diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus.
    • Smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases cessation
    • Moderate alcohol consumption
    • Heart-healthy diet and regular Regular Insulin exercise

Secondary prevention

  • Implantable cardioverter-defibrillator (ICD):
    • Terminates ventricular arrhythmias when they recur
    • Recommended in the following:
      • Survivors of SCA (from VT VT Ventricular tachycardia is any heart rhythm faster than 100 beats/min, with 3 or more irregular beats in a row, arising distal to the bundle of his. Ventricular tachycardia is the most common form of wide-complex tachycardia, and it is associated with a high mortality rate. Ventricular Tachycardia/ VF VF Ventricular fibrillation (VF or V-fib) is a type of ventricular tachyarrhythmia (> 300/min) often preceded by ventricular tachycardia. In this arrhythmia, the ventricle beats rapidly and sporadically. The ventricular contraction is uncoordinated, leading to a decrease in cardiac output and immediate hemodynamic collapse. Ventricular Fibrillation (V-fib)) with heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) and cardiomyopathy Cardiomyopathy Cardiomyopathy refers to a group of myocardial diseases associated with structural changes of the heart muscles (myocardium) and impaired systolic and/or diastolic function in the absence of other heart disorders (coronary artery disease, hypertension, valvular disease, and congenital heart disease). Cardiomyopathy: Overview and Types
      • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with structural heart disease (associated with hemodynamically unstable VT VT Ventricular tachycardia is any heart rhythm faster than 100 beats/min, with 3 or more irregular beats in a row, arising distal to the bundle of his. Ventricular tachycardia is the most common form of wide-complex tachycardia, and it is associated with a high mortality rate. Ventricular Tachycardia or spontaneous sustained VT VT Ventricular tachycardia is any heart rhythm faster than 100 beats/min, with 3 or more irregular beats in a row, arising distal to the bundle of his. Ventricular tachycardia is the most common form of wide-complex tachycardia, and it is associated with a high mortality rate. Ventricular Tachycardia)
  • Antiarrhythmic therapy:

Clinical Relevance

The following conditions are causes of cardiac arrest:

  • Pericardial tamponade Tamponade Pericardial effusion, usually of rapid onset, exceeding ventricular filling pressures and causing collapse of the heart with a markedly reduced cardiac output. Pericarditis: a clinical syndrome caused by the accumulation of fluid in the pericardial space Pericardial Space Pericardial Effusion and Cardiac Tamponade; results in reduced ventricular filling Ventricular filling Cardiac Cycle and subsequent hemodynamic compromise. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with Beck’s triad Beck’s triad The triad describes the classic findings in cardiac tamponade: hypotension, jugular venous distension, muffled heart sounds on auscultation. Pericardial Effusion and Cardiac Tamponade ( hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension, distended jugular veins Veins Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia. Veins: Histology, and muffled heart sounds Muffled Heart Sounds Pericardial Effusion and Cardiac Tamponade). Tamponade Tamponade Pericardial effusion, usually of rapid onset, exceeding ventricular filling pressures and causing collapse of the heart with a markedly reduced cardiac output. Pericarditis can cause cardiac arrest. Treatment is with pericardiocentesis Pericardiocentesis Puncture and aspiration of fluid from the pericardium. Cardiac Surgery.
  • Tension pneumothorax Tension Pneumothorax Pneumothorax: an abnormal collection of air in the pleural space Pleural space The thin serous membrane enveloping the lungs (lung) and lining the thoracic cavity. Pleura consist of two layers, the inner visceral pleura lying next to the pulmonary parenchyma and the outer parietal pleura. Between the two layers is the pleural cavity which contains a thin film of liquid. Pleuritis due to laceration Laceration Torn, ragged, mangled wounds. Blunt Chest Trauma of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy. Types of pneumothorax Pneumothorax A pneumothorax is a life-threatening condition in which air collects in the pleural space, causing partial or full collapse of the lung. A pneumothorax can be traumatic or spontaneous. Patients present with a sudden onset of sharp chest pain, dyspnea, and diminished breath sounds on exam. Pneumothorax include simple (spontaneous) and tension. Physical exam findings include decreased breath sounds, hyperresonance on percussion Percussion Act of striking a part with short, sharp blows as an aid in diagnosing the condition beneath the sound obtained. Pulmonary Examination, and tracheal deviation Tracheal Deviation Pneumothorax. Treatment includes needle decompression Needle Decompression Pneumothorax and chest tube placement Tube placement Surgical procedure involving the creation of an opening (stoma) into the chest cavity for drainage; used in the treatment of pleural effusion; pneumothorax; hemothorax; and empyema. Thoracic Surgery.
  • Coronary heart disease Coronary heart disease Coronary heart disease (CHD), or ischemic heart disease, describes a situation in which an inadequate supply of blood to the myocardium exists due to a stenosis of the coronary arteries, typically from atherosclerosis. Coronary Heart Disease: acute anginal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways because of partial or total occlusion of 1 or more coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology due to advanced coronary heart disease Coronary heart disease Coronary heart disease (CHD), or ischemic heart disease, describes a situation in which an inadequate supply of blood to the myocardium exists due to a stenosis of the coronary arteries, typically from atherosclerosis. Coronary Heart Disease. Three clinical entities can be identified: unstable angina Unstable angina Precordial pain at rest, which may precede a myocardial infarction. Stable and Unstable Angina, non-ST-segment elevation myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction ( MI MI MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction), and ST-segment elevation MI MI MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction. Diagnosis is by ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) and cardiac enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes. Treatment is with percutaneous coronary intervention Percutaneous coronary intervention A family of percutaneous techniques that are used to manage coronary occlusion, including standard balloon angioplasty (percutaneous transluminal coronary angioplasty), the placement of intracoronary stents, and atheroablative technologies (e.g., atherectomy; endarterectomy; thrombectomy; percutaneous transluminal laser angioplasty). Ptca was the dominant form of pci, before the widespread use of stenting. Cardiac Surgery and/or medical management.
  • Cardiomyopathies Cardiomyopathies A group of diseases in which the dominant feature is the involvement of the cardiac muscle itself. Cardiomyopathies are classified according to their predominant pathophysiological features (dilated cardiomyopathy; hypertrophic cardiomyopathy; restrictive cardiomyopathy) or their etiological/pathological factors (cardiomyopathy, alcoholic; endocardial fibroelastosis). Cardiomyopathy: Overview and Types: a group of myocardial diseases associated with impaired systolic and diastolic function. Classified into dilated, hypertrophic, and restrictive cardiomyopathies Cardiomyopathies A group of diseases in which the dominant feature is the involvement of the cardiac muscle itself. Cardiomyopathies are classified according to their predominant pathophysiological features (dilated cardiomyopathy; hypertrophic cardiomyopathy; restrictive cardiomyopathy) or their etiological/pathological factors (cardiomyopathy, alcoholic; endocardial fibroelastosis). Cardiomyopathy: Overview and Types. Potential complications include heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR), arrhythmias, and sudden death. Treatment varies based on type and includes medications and/or surgery.

References

  1. Marine, J., Russo, A., Knight, B., Levy, S., Yeon, S. (2020) Secondary prevention of sudden cardiac death in heart failure and cardiomyopathy. UpTodate. Retrieved December 19, 2020, from https://www.uptodate.com/contents/secondary-prevention-of-sudden-cardiac-death-in-heart-failure-and-cardiomyopathy
  2. Panchal, A. et al. (2020). Part 3: Adult Basic and Advanced Life Support: 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation 142 (16): S366–S468. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000916
  3. Podrid, P. (2019). Overview of sudden cardiac arrest and sudden cardiac death. UpToDate. Retrieved December 5, 2020, from https://www.uptodate.com/contents/overview-of-sudden-cardiac-arrest-and-sudden-cardiac-death
  4. Rittenberger, J and Callaway, C. (2020). Post-cardiac arrest management in adults. UpToDate. Retrieved December 5, 2020, from https://www.uptodate.com/contents/post-cardiac-arrest-management-in-adults
  5. Podrid, P. (2019). Pathophysiology and etiology of sudden cardiac arrest. UpToDate. Retrieved December 5, 2020, from https://www.uptodate.com/contents/pathophysiology-and-etiology-of-sudden-cardiac-arrest
  6. Rittenberger, J and Callaway, C. (2020). Post-cardiac arrest management in adults. UpToDate. Retrieved December 5, 2020, from https://www.uptodate.com/contents/post-cardiac-arrest-management-in-adults
  7. Topjian, A. et al. (2020). Part 4: Pediatric Basic and Advanced Life Support: 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation 142(16):S469–S523.

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