Cardiovascular Emergencies Objectives Understand the causes and management

Cardiovascular Emergencies

Objectives • Understand the causes and management priorities of bradycardia in children. • Identify risk factors for serious causes of syncope in children. • Describe the resuscitation and stabilization of a child presenting with cardiopulmonary failure. • List the strategies for prevention of submersion injuries in infants and children.

Case Presentation • You are called to a suburban home for toddler found submerged in backyard pool. • A sobbing mother is performing CPR on 15 -month-old girl on pool deck. • As you take over resuscitation, the mother tells you, “The phone rang; I was only gone for 5 minutes!”

General Assessment: PAT Appearance Unconscious, unresponsive; poor muscle tone Work of Breathing No spontaneous respirations Circulation to Skin Ashen, cyanosis of hands and lips What is your general impression?

General Impression and Management Priorities • General impression: – Sick: respiratory arrest; possible cardiorespiratory failure § Unresponsive, apneic, abnormal circulation to skin – Physiologic problem: global hypoxemic –ischemic event • Immediate management: – Start oxygenation and ventilation while assessing for spontaneous circulation.

Initial Assessment: ABCDEs • Airway — patent • Breathing —good air movement with bag-mask ventilation; wet crackles on auscultation • Circulation — HR 20; femoral pulse barely palpable; capillary refill > 5 seconds; BP not obtained • Disability — pupils dilated, sluggishly reactive; unresponsive to pain • Exposure — no bruises, no signs of injury What is your overall assessment?

Case Progression • Cardiopulmonary failure due to hypoxemia. – Chest compressions are indicated for HR < 60. • No evidence of associated injuries. – Consider spinal injury. § Less likely in toddler submersion than with adolescent diving injury. – Consider nonaccidental trauma. § No “red flags” What are your management priorities?

Management Priorities • BLS: – Place on spine board. – Open airway; begin bag-mask ventilations, 100% 02. – Perform chest compressions. – Dry to prevent further heat loss/hypothermia. • ALS: – IV access, consider endotracheal intubation. – Epinephrine, 0. 01 mg/kg IV/IO, or 0. 1 mg/kg by endotracheal tube; repeat every 3– 5 minutes.

Transport Decision: Stay or Go? • BLS: – Rapid transport to nearest appropriate ED. – Continuous reassessment for return of pulse and circulation en route. • ALS: – Transport after airway/ventilation is secure, IV/IO access is established, and the first dose of epinephrine is given. – Do not delay transport if vascular access fails.

Key Concepts: Bradycardia • Treatable causes of bradycardia with poor perfusion: – – – – Hypoxemia Hypothermia Hypovolemia Heart block Toxins, poisoning, drugs Tampondae, cardiac Tension pneumothorax Trauma (Head injury)

Key Concepts: Bradycardia with Submersion Event • Bradycardia in near-drowning reflects significant hypoxia and myocardial ischemia. – The brain and other vital organs may also have suffered ischemic injury. – Rapid support of ventilation and oxygenation will reduce the risk of secondary injury. – The drug of choice is oxygen, followed by epinephrine.

Key Concepts: Drowning Prevention • Pool drowning prevention: – Close supervision – Four-sided pool fence – Self-locking gate – Pool alarms • Open water drowning prevention: – Supervision of all age groups. – Use of personal floatation devices. – Educate teens about dangers of alcohol and water sports. • Risk awareness, as toddler drownings may occur in shallow water.

Key Concepts: Injury Prevention • Multiple strategies are necessary for an effective injury prevention program. – Passive strategies – Legislative action – Enforcement of laws – Education

Case Progression • Oxygen provided by bag-mask device, compressions continued. – After 30 seconds, the heart rate increases to 80 per minute and compressions are discontinued. – After 1 minute, the heart rate is 120 per minute; spontaneous respirations return.

Case Progression • En route: – Supplemental oxygen is delivered by mask. – Blankets are applied to prevent heat loss.

ED Course • In the ED: – The child shows progressive improvement in level of consciousness, asking for her mommy. – She remains hemodynamically stable. – Sa. O 2 is 94% on 100 % O 2, and chest X-ray shows diffuse infiltrates. – She is admitted to the pediatric intensive care unit and transferred to a ward the next morning. • Diagnosis: near drowning; pulmonary edema • Outcome: weaned from oxygen on day 2; home on day 4 with normal neurologic exam.

Summary • Submersion results in hypoxia, leading to bradycardia, tissue ischemic injury, and eventually, cardiac arrest. • Early oxygenation and ventilation are the most effective ways to restore spontaneous circulation. • Prehospital management is a major determinant of outcome in children with submersion injury. • Submersion injuries are predictable — prevention is the best treatment!

Case Presentation • You are dispatched to a middle-school athletic field for a child with loss of consciousness. • A 13 -year-old boy is lying on the grass, receiving CPR by his coach. • The coach tells you that the child collapsed while running for a ball, and that “this happened before. ” What is the first thing you will do on arrival?

General Assessment: PAT Work of Breathing No spontaneous respirations Appearance Unresponsive Circulation to Skin Pale, cyanotic What is your general impression?

General Impression and Management Priorities • General impression: – Sick: cardiopulmonary failure § Scenario suggests primary cardiac event. • Management: – BLS: apply AED. – ALS: “quick look” on monitor/defibrillator.

Initial Assessment: ABCDEs • Since this was a witnessed collapse, attach the AED as soon as available. – Airway: patent – Breathing: no chest movement – Circulation: absent pulses, no heart sounds; shockable rhythm on AED, ventricular fibrillation (VF) on monitor – Disability: unresponsive to pain – Exposure: no bruising or signs of injury What is your overall assessment?

Case Progression • VF cardiac arrest – Possible mechanisms: § Primary cardiac disease § Trauma (direct blow to precordium) § Toxin/drugs What are your management priorities?

Management Priorities • BLS: – – Establish absence of respirations, pulse. Turn on AED. Attach AED electrode pads. Analyze rhythm. § Shock if advised, then resume CPR immediately for five cycles (2 minutes). § If no shock is advised, resume CPR for five cycles (2 minutes). – Check for signs of circulation and rhythm every 2 minutes and repeat sequence from analyze rhythm.

Management Priorities • ALS: BLS priorities plus: – Place on monitor, check rhythm. – Defibrillate. § 2 joules/kg § Resume CPR for five cycles (2 minutes), check rhythm; if VF, defibrillate with 4 joules/kg. – Resume CPR immediately. – Intubate, secure airway (optional). – Obtain vascular access. – Epinephrine 0. 01 mg/kg (1: 10, 000) IV or 0. 1 mg/kg ETT (1: 1000); repeat every 3 -5 minutes. – After five cycles (2 minutes); check rhythm. If shockable: – Defibrillate (4 joules/kg). – Resume CPR immediately. – Consider antiarrhythmic. § Lidocaine 1 mg/kg IV/IO/ET § Amiodarone 5 mg/kg IV/IO

Transport Decision: Stay or Go? • Stay on scene and treat until a pulse is established or the child is asystolic. • As in adults, the outcome is strongly linked to resuscitation in the field. – Survival statistics are poor for a child brought to the ED in asystole.

Key Concepts: Ventricular Fibrillation • Airway management and correction of hypoxia while making rhythm diagnosis is critical. • Although pediatric VF is uncommon, early recognition and treatment improve the chance of successful resuscitation. – Early defibrillation increases the survival rate. • Increased availability and use of AEDs in community can improve outcomes for both pediatric and adult VF victims.

Key Concepts: High-risk Groups/Causes for VF • Cardiomyopathies • Coronary artery abnormalities: – Post-Kawasaki disease aneurysms, thrombi – Congenital anomalies • Direct blow to chest • Dysrhythmia syndromes

Key Concept: Identifying Cardiac Syncope • Most fainting spells are benign, but “red flags” can identify serious cardiac causes. – Was the episode associated with chest pain? – Was there a brief or absent aura? – Were there palpitations prior to fainting? – Did it occur during exercise? – Is there a family history of sudden death?

Case Progression • At scene: – Rescue breathing and cardiac compressions started. – AED shows VF — converted to NSR on second shock. – Vascular access obtained • En route: – Lidocaine bolus 1 mg/kg IV and then 20 micrograms/kg/min infusion or bolus every 15 minutes – Continues in sinus rhythm

ED Course • In the ED: – Lead 2 rhythm strip shows QTc = 0. 52 – The mother arrives and reports three prior brief episodes of exerciseassociated syncope; sudden death at the age of 28 in uncle. • Outcome: child diagnosed with long QTc syndrome. A pacemaker is placed. The patient is discharged neurologically intact 5 days later.

Summary • Most episodes of syncope in children are benign. • Ventricular fibrillation is a rare cause of loss of consciousness in pediatrics. • Early recognition of VF and defibrillation improve survival rates. • When VF is diagnosed, standard cardiac resuscitation protocols should be followed, regardless of the age of the patient.

Summary • The primary cause of cardiopulmonary arrest in children is severe hypoxia associated with respiratory failure. – Asystole or profound bradycardia is the most common arrest rhythm on EMS arrival. • Rapid intervention and return of vital signs in the field are associated with good outcome. – Patients with ventricular fibrillation who have return of sinus rhythm have good survival rates. – Children with asystole as the presenting rhythm on scene rarely survive.