{
 "topic": "Respiratory Failure",
 "slug": "respiratory-failure",
 "category_id": 15555,
 "summary": "The mechanisms, formal diagnostic criteria, and causes of pediatric respiratory failure, and how management differs by cause and by chronicity.",
 "written_by": "claude-sonnet",
 "references": [
  {
   "title": "Kliegman R. Nelson Textbook of Pediatrics 2-Volume Set 22ed 2024",
   "author": null,
   "pages": [
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   ]
  },
  {
   "title": "Pediatric Pulmonology",
   "author": "American Academy of Pediatrics Section on Pediatric Pulmonology and Sleep Medicine;Michael J Light;Kristin Van Hook;",
   "pages": [
    1152
   ]
  },
  {
   "title": "Caring for the Hospitalized Child",
   "author": "Section on Hospital Medicine, American Academy of Pediatrics;Jeffrey C. Gershel;Daniel A. Rauch;",
   "pages": [
    776,
    778
   ]
  },
  {
   "title": "2021_Fleisher_&_Ludwig's_Textbook_of_Pediatric_Emergency_Medicine.epub",
   "author": null,
   "pages": []
  },
  {
   "title": "Cover",
   "author": "Vitalsource Download",
   "pages": [
    7758
   ]
  },
  {
   "title": "Algorithms in Pediatrics",
   "author": null,
   "pages": [
    182
   ]
  }
 ],
 "short": [
  {
   "title": "In short",
   "content": "- Respiratory failure = oxygenation and/or ventilation insufficient to meet the body's metabolic demands; it is often the end stage of respiratory distress if not intercepted early.\n- Conceptually it results from a \"respiratory balance\" failure: ventilatory muscle power and central respiratory drive must overcome the respiratory load \u2014 failure occurs when muscle power/central drive falls and/or load rises enough that adequate ventilation cannot be sustained.\n- Formal criteria (2 clinical + 1 laboratory finding suggest respiratory failure): clinical \u2014 tachypnea/bradypnea/apnea/irregular respirations, pulsus paradoxus >30 mm Hg, stridor/wheeze/grunting, severe retractions with accessory muscle use, cyanosis in 40% O2, altered consciousness, weak/absent cough or gag, poor muscle tone; laboratory \u2014 PaO2 <60 mmHg in 60% O2, PaCO2 >60 mmHg and rising, pH <7.3.\n- Infants/toddlers are physiologically predisposed: proportionally large tongue, narrow subglottic airway, small/compliant airways, fewer alveoli, more compliant chest wall, more fatigable respiratory muscles, and an immature respiratory center.\n- Site of pathology predicts the physical exam pattern: extrathoracic airway obstruction produces stridor with markedly increased retractions; intrathoracic (extrapulmonary or intrapulmonary) obstruction produces wheezing; alveolar/interstitial disease produces grunting and crackles with the most severe tachypnea and retractions.\n- Etiologies span 5 categories: upper airway obstruction (adenotonsillar hypertrophy, choanal atresia, croup, epiglottitis, foreign body, retropharyngeal abscess), lower airway obstruction (asthma, bronchiolitis, bacterial tracheitis), parenchymal lung disease (ARDS, aspiration, pneumonia, pulmonary contusion), pulmonary edema (heart failure), neuromuscular weakness (botulism, Guillain-Barr\u00e9, muscular dystrophy, spinal cord injury, SMA), and thoracic mass effect (effusion/empyema, pneumothorax, tumor, ascites).\n- Spirometry distinguishes restrictive from obstructive disease: both reduce FEV1 and vital capacity, but the FEV1/vital-capacity ratio stays normal in restrictive disease and falls in obstructive disease; obstructive disease also causes air trapping with elevated functional residual capacity and residual volume.\n- In cystic fibrosis, about 90% of patients ultimately die of respiratory failure, often precipitated by a pulmonary exacerbation, hemoptysis, pneumothorax, or nonpulmonary surgery; noninvasive ventilation is increasingly used to rest respiratory muscles in this population.\n- Give supplemental oxygen cautiously in chronic CO2 retainers (e.g., advanced CF), since it can suppress hypoxic ventilatory drive.\n- Acute respiratory failure from a severe infectious illness can be recovered from fully with aggressive treatment \u2014 intensive antibiotics, postural drainage, oxygen, and ventilatory support as needed continued for 1\u20132 weeks after the patient returns to baseline."
  }
 ],
 "long": [
  {
   "title": "Definition",
   "content": "Respiratory distress is a clinical state of abnormal respiratory rate or effort, most often manifesting as tachypnea and increased work of breathing (a child with neurologic illness may instead show an abnormal respiratory pattern or bradypnea). Respiratory failure is a clinical state of inadequate oxygenation, inadequate ventilation, or both, and represents the end stage of respiratory distress if it is not recognized and treated promptly. More formally, respiratory failure occurs when oxygenation and ventilation together are insufficient to meet the body's metabolic demands, arising from abnormalities in the lungs/airways, the chest wall and muscles of breathing, or the central/peripheral chemoreceptors that drive breathing."
  },
  {
   "title": "Pathophysiology",
   "content": "Adequate ventilation depends on a balance in which ventilatory muscle power and central respiratory drive must be sufficient to overcome the respiratory load. Respiratory failure results when muscle power and/or central drive fall, and/or the respiratory load rises, to the point that a child cannot sustain adequate ventilation. Infants and toddlers are disproportionately vulnerable to this imbalance because of anatomic and physiologic immaturity: a proportionally large tongue and narrow subglottic airway, small and highly compliant airways, fewer alveoli, a more compliant (less supportive) chest wall, respiratory muscles that fatigue more easily, and an immature respiratory center. Children with underlying metabolic, genetic, or developmental disorders carry additional risk from poor airway control, chronic aspiration, severe muscle weakness, scoliosis, and restrictive lung disease."
  },
  {
   "title": "Etiology",
   "content": "Causes of respiratory failure fall into recognizable categories. Upper airway obstruction: adenotonsillar hypertrophy, choanal atresia/stenosis, croup, epiglottitis/supraglottitis, excessive or inspissated secretions, foreign body, neuromuscular disease with poor airway control, and retropharyngeal abscess. Lower airway obstruction: asthma, bronchiolitis, bacterial tracheitis. Parenchymal lung disease: acute respiratory distress syndrome, aspiration or inhalation injury, exacerbation of chronic lung disease, noncardiogenic pulmonary edema, pneumonia, and pulmonary contusion. Pulmonary edema from heart failure is a separate category. Neuromuscular weakness or paralysis: botulism, Guillain-Barr\u00e9 syndrome, muscular dystrophy, spinal cord injury, spinal muscular atrophy, transverse myelitis, and other underlying neuromuscular conditions. Thoracic mass effect: ascites, pleural effusion or empyema, pneumothorax, and tumor. Cardiovascular pathology (e.g., left-to-right shunts causing decreased lung compliance) can also manifest as respiratory distress. In cystic fibrosis specifically, thickened airway secretions, bacterial infection, mucous hypersecretion, bronchoconstriction, mucosal edema, inflammation, and fibrosis combine to fatigue the respiratory muscles and drive progressive respiratory failure; about 90% of CF patients eventually succumb to it, often precipitated by a pulmonary exacerbation, hemoptysis, pneumothorax, or surgery for a nonpulmonary problem."
  },
  {
   "title": "Clinical features",
   "content": "The physical exam pattern correlates with the anatomic site of pathology. Extrathoracic airway lesions produce stridor with markedly increased respiratory rate and severe retractions. Intrathoracic extrapulmonary and intrapulmonary lesions both produce wheezing, with progressively greater respiratory rate and retractions for intrapulmonary disease. Alveolar or interstitial disease produces the most severe tachypnea and retractions, manifesting as grunting and crackles. Formal criteria for respiratory failure combine clinical and laboratory findings, and it is considered likely when at least two clinical findings and one laboratory finding are present together. Clinical findings include tachypnea, bradypnea, apnea, or irregular respirations; pulsus paradoxus greater than 30 mm Hg; stridor, wheeze, or grunting; severe retractions with accessory muscle use; cyanosis while receiving 40% oxygen; depressed or heightened level of consciousness with decreased response to pain; a weak or absent cough or gag reflex; and poor muscle tone. Laboratory findings include PaO2 below 60 mmHg while receiving 60% oxygen (excluding cyanotic heart disease), PaCO2 above 60 mmHg and rising, and pH below 7.3."
  },
  {
   "title": "Diagnostics",
   "content": "Diagnosis combines the clinical/laboratory criteria above with pulmonary function testing when feasible, which helps distinguish restrictive from obstructive disease patterns: both reduce FEV1 and vital capacity, but the FEV1-to-vital-capacity ratio remains normal in restrictive disease and falls in obstructive disease; obstructive intrathoracic airway disease also causes air trapping with abnormally elevated functional residual capacity and residual volume. Reactive airways dysfunction syndrome is one specific pattern to recognize: documented absence of prior respiratory symptoms, onset after a single high-level irritant exposure (gas, smoke, fumes, vapors), symptom onset within 24 hours persisting at least 3 months, asthma-like symptoms (cough, wheeze, dyspnea), airflow obstruction on pulmonary function testing (with or without methacholine hyperresponsiveness), and exclusion of other pulmonary disease."
  }
 ],
 "clinical": [
  {
   "title": "Management",
   "content": "Prompt recognition and early intervention in respiratory distress prevents progression to respiratory failure and cardiorespiratory arrest, so treat respiratory distress as a time-sensitive warning sign rather than waiting for the formal failure criteria to appear. Provide supplemental oxygen to correct hypoxemia, but do so cautiously in patients with chronic CO2 retention (e.g., advanced cystic fibrosis), since aggressive oxygen supplementation can suppress hypoxic ventilatory drive. A rising PaCO2 may require ventilatory assistance; noninvasive support (CPAP or BiPAP) can rest fatigued respiratory muscles and is increasingly used, including in CF, before escalating to invasive ventilation.\n\nTarget the underlying cause: intensify airway clearance and antibacterial therapy for infectious/suppurative causes, treat right-sided heart failure vigorously when present, and evaluate for and treat precipitating comorbidities (e.g., atypical infection, allergic bronchopulmonary aspergillosis, pneumothorax) that can trigger acute decompensation in a patient with chronic lung disease. Endotracheal or bronchoscopic suction may be needed to clear inspissated secretions and can be repeated daily. High-dose steroids have anecdotal benefit in some severe acute presentations. When acute respiratory failure follows a severe infectious illness in a patient with only mild-to-moderate underlying lung disease, intensive therapy is warranted because full recovery to baseline is achievable; continue intensive intravenous antibiotics and postural drainage for 1\u20132 weeks after the patient has returned to baseline status, since recovery is often slow."
  }
 ]
}