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Dysrhythmias are classified according to the heart rate, QRS width, and the patient’s clinical stability.
Sinus bradycardia in the neonate always requires aggressive evaluation and treatment.
Infants with paroxysmal supraventricular tachycardia (PSVT) may present in a low output state with irritability, poor feeding, tachypnea, and diaphoresis.
An accessory pathway is the most common mechanism for PSVT in the child. Digoxin may precipitate ventricular tachycardia (VT), and therefore should only be used under the supervision of a pediatric cardiologist.
Atrial fibrillation or atrial flutter associated with accessory pathway disease or hypertrophic cardiomyopathy (HC) puts a child at high risk for 1:1 conduction abnormalities, ventricular tachycardia, and sudden death.
Either amiodarone or lidocaine may be used for shock-refractory ventricular fibrillation and ventricular tachycardia.
Concerning risk factors for hypertrophic cardiomyopathy (HCM) and sudden death include a family history of sudden death, exercise-induced symptoms, and a murmur on physical examination.
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Disorders of rate and rhythm are fortunately rare in the pediatric population. The most common dysrhythmia is supraventricular tachycardia. Rhythm disturbances, such as sinus bradycardia, can be life-threatening, particularly in the neonate.
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Dysrhythmias in children that are the result of cardiac lesions have a poorer prognosis than patients with a structurally normal heart. Noncardiac causes, such as hypoxia, electrolyte disturbances, toxins, and inflammatory disease, must be considered, as should cardioactive drugs, such as digoxin or over-the-counter cold remedies. The initial evaluation includes an electrocardiogram (ECG).
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Age is an important consideration in the child presenting with a dysrhythmia. Age is also a factor in the clinical presentation of the dysrhythmia. A young infant may present with poor feeding, tachypnea, irritability, or signs of a low output state. Caregivers often note that their baby is “not acting right.” An older child often presents with more specific symptoms, such as syncope from decreased cerebral blood flow, chest pain from decreased coronary blood flow, or palpitations. The ventricular rate in third-degree heart block may be adequate for the 2-month-old child, but will not provide an adequate cardiac output for a 12-year-old child. Adolescents involved in competitive athletics who present with syncope, palpitations, or worrisome chest pain should be evaluated promptly. Normal ranges for heart rate and blood pressure are listed in Tables 43-1 and 43-2.
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The initial emergency management of dysrhythmias is dependent on three factors: rate, QRS width, and clinical stability. Management decisions should be based on 12-lead ECG interpretation, since single-lead monitor strips can be misleading. Rapid rates may appear supraventricular in origin in the child with tachycardia. Children tolerate most rhythm disturbances well, providing ample time for precise interpretation.
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Since dysrhythmias are relatively uncommon in the pediatric patient population, high-fidelity simulation has been shown to be useful for training purposes. Simulation training has been shown to decrease stress levels and increase levels of skill satisfaction in emergency care providers. Both technical and nontechnical skills showed significant improvement in those ...