Abstract
Introduction: Negative pressure pulmonary edema (NPPE) is a potentially life-threatening complication that develops rapidly following acute upper airway obstruction. The condition is rare, dramatic but resolves quickly. Prompt recognition and appropriate supportive treatment may prevent unnecessary investigations and iatrogenic complications. Methods: We describe a spectrum of etiologies and clinical manifestation of pediatric NPPE in our center and review of previous publications. Conclusion: The etiology for the development of NPPE in children has shifted over the years. Although dramatic in presentation, this type of pulmonary edema often resolves quickly with minimal support.
| Original language | English |
|---|---|
| Pages (from-to) | 3596-3599 |
| Number of pages | 4 |
| Journal | Pediatric Pulmonology |
| Volume | 58 |
| Issue number | 12 |
| Early online date | 22 Sep 2023 |
| DOIs | |
| State | Published - Dec 2023 |
Bibliographical note
Publisher Copyright:© 2023 The Authors. Pediatric Pulmonology published by Wiley Periodicals LLC.
Funding
NPPE is a rare but serious complication that develops rapidly at the onset or at the relief of acute upper airway obstruction (UAO) in a spontaneously breathing patient.3–5 The pathophysiology of NPPE stems from the markedly negative thoracic pressure induced by inspiratory effort against an obstructed upper airway. Clinical characteristics of NPPE are similar in most reports and include rapid onset during airway obstruction, or shortly after the relief of the obstruction, dyspnea, progressive cyanosis, anxiety, and increased work of breathing, excessive amount of pink frothy secretions from the lungs, and crackles on pulmonary auscultation. The radiographic image is of alveolar filling. The resolution of pulmonary edema usually occurs within 48 h. Diagnosis is based upon scenario, clinical and radiological findings, time course and exclusion of other diagnosis.3,4,6 Therapy is mainly supportive. Prompt recognition may prevent unnecessary investigation, treatments (e.g., corticosteroids, antibiotics) and iatrogenic complications. After reviewing the pediatric literature regarding NPPE, we observed a shift in the etiology of NPPE in children throughout the years. Early reports (1980−2000), described mainly infectious cause of airway obstruction, usually complicated further by airway manipulations. In the two largest pediatric NPPE series 16/17 and 33/45 children with NPPE had epiglottitis or croup.4,7 Over the past two decades, there were anecdotal reports, mostly in anesthesiology and surgical literature.8,9 This shift in etiology may have been the result of the introduction of Hib vaccine in 1993, which led to a decline in acute severe infectious airway obstruction. We present a series of seven children over 5 years (five 12−16 years, one 7 years old, and one infant). In previous publication and in our current report, the true incidence of pediatric NPPE in acute UAO or among pediatric pulmonary edema remains unknown. Three patients developed edema in post-anesthesia setting; two cases resulted from accidental strangulation, one with a foreign body in the trachea and one following laryngotracheobronchitis. All the patients were previously heathy. Rapid clinical and radiologic resolution was observed in all patients with hospital discharge after 1−3 days. None of the cases had further respiratory complications. This clinical description is characteristic of NPPE. NPPE is thought to be more common in young and fit individuals that may produce significant negative pressures.5 Supporting previous reports, in our series, two patients that were avid athletes developed NPPE after brief episode of airway obstruction. Interestingly, 2/7 were obese. This may suggest that obesity is an additional risk factor for developing NPPE in the setting of anesthesia. The plausible mechanism is chronic upper airway collapsibility of the upper respiratory airway that might result in significant negative inspiratory pressure.10 The various etiologies and spectrum of age in this case series may assist pediatricians and ED physicians better recognizing future similar cases.
Keywords
- negative pressure pulmonary edema
- post-obstruction edema
- strangulation
- upper airway obstruction