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Respiratory failure is the most common cause of cardiac arrest in pediatric patients.
It is important to recognize respiratory distress early so that actions can be taken to prevent respiratory failure whenever possible.
If respiratory failure does occur, prompt intervention will give the patient the best chance for survival with the least neurologic sequelae.
Young children have less physiologic reserve and can deteriorate very rapidly.
In a critical situation, the emergency physician has the task of not only making quick resuscitation management decisions but must also consider age-related anatomic differences, appropriate equipment, and drug-dosage differences when caring for infants and children.
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ANATOMY AND PHYSIOLOGY
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Children have anatomic and physiologic differences that should be considered when evaluating a pediatric patient presenting in respiratory distress. Young infants may be obligate nose breathers, and any degree of obstruction of the nasal passages can produce respiratory difficulty.
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The chest wall of children is more flexible and the muscles are less developed compared to adults. The diaphragm is more prone to fatigue. The limitation of diaphragmatic movement by gastric distention, and increased residual capacity from air trapping from asthma, bronchiolitis, or foreign body obstruction can result in reduction of tidal volume, which may produce respiratory failure. The relatively smaller lower airways are especially vulnerable to mucus plugging and ventilation–perfusion mismatch associated with common diseases of the lower airways, such as asthma and bronchiolitis.1,2
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The actual area available for gas exchange in infants and young children is relatively limited. Alveolar space doubles by 18 months of age and triples by 3 years of age. The limited ability to recruit additional alveoli makes the infant dependent on increasing the respiratory rate to augment minute ventilation and eliminate carbon dioxide. Tachypnea is therefore a universal finding in infants and young children in respiratory distress.1 The combination of increased muscle exertion and the need to sustain a rapid respiratory rate can result in progressive muscle fatigue and respiratory failure. This is especially true in young infants, who have a limited metabolic reserve. Children have about twice the oxygen consumption as adults,1 and they have proportionally smaller functional residual capacity. Infants and children have the potential to desaturate more quickly than adults1,3 (see Chapter 18 for airway differences between infants and children).
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Most commonly, a patient in respiratory distress will present to the ED with a history of difficulty breathing. Parents may note coughing, rapid noisy breathing, or a change in behavior. Feeding problems are often a sign of respiratory compromise in infants. In older children, wheezing or decreased physical activity may be presenting complaints.
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The past medical history is essential in determining the etiology of the acute problem. Infants with a history of significant prematurity may have bronchopulmonary dysplasia, a chronic lung disease syndrome ...