Management of Airway Obstruction and Stridor in Pediatric Patients

Table of Contents

 

Children are more likely than adults to experience upper airway obstruction, which often presents with stridor. Because stridor is a sign and not a diagnosis, the underlying etiology must be determined to guide management. In this issue, you will learn:

Key findings on the history and physical examination that will help make the diagnosis

How to determine when imaging studies are necessary and which provide the most information

Evidence-based recommendations for proper management of infectious, noninfectious, and chronic etiologies of stridor

How to decide when a patient can be safely discharged home and when they need to be admitted 

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Anatomy and Pathophysiology
6. Etiology and Epidemiology
   1. Croup
   2. Epiglottitis
   3. Bacterial Tracheitis
7. Differential Diagnosis
8. Prehospital Care
9. Emergency Department Evaluation
   1. History
      1. Patient Age
      2. Timing and Onset of Symptoms
      3. Precipitating Events
   2. Physical Examination
      1. Initial Evaluation
      2. Examination
10. Diagnostic Studies
    1. Radiographic Imaging
    2. Endoscopy
       1. Acute Stridor
       2. Chronic Stridor
11. Management
    1. Emergent Airway Management
    2. Management of Infectious Etiologies
       1. Croup
       2. Epiglottitis
       3. Bacterial Tracheitis
       4. Mononucleosis
       5. Diphtheria
       6. Deep Space Neck Infections
    3. Management of Noninfectious Etiologies
       1. Foreign Bodies
       2. Anaphylaxis
       3. Airway Ingestions and Burns
       4. Vocal Cord Disorders
    4. Management of Chronic Etiologies
       1. Laryngomalacia
       2. Tracheomalacia
       3. Subglottic and Tracheal Stenosis
       4. Rings, Slings, and Other Etiologies
12. Special Circumstances
13. Controversies and Cutting Edge
14. Disposition
15. Summary
16. Key Points
17. Risk Management Pitfalls for Management of Children With Stridor
18. Time- and Cost-Effective Strategies
19. Case Conclusions
20. Clinical Pathway for Management of Pediatric Patients With Stridor in the Emergency Department
21. Tables and Figures
    1. Table 1. Differential Diagnosis of Stridor
    2. Figure 1. Airway Diameter and the Effect of Edema on Resistance in Infants and Adults
    3. Figure 2. Lateral Neck X-ray Demonstrating the Thumbprint Sign of Edema of the Epiglottis
    4. Figure 3. Lateral Neck X-Ray Demonstrating 2 Magnets Around the Epiglottis
    5. Figure 4. Neck MRIs Demonstrating a Soft-Tissue Mass Obstructing the Airway at the Base of the Tongue
22. References

Abstract

Stridor is a result of turbulent air-flow through the trachea from upper airway obstruction, and although in children it is often due to croup, it can also be caused by noninfectious and/or congenital conditions as well as life-threatening etiologies. The history and physical examination guide initial management, which includes reduction of airway inflammation, treatment of bacterial infection, and, less often, imaging, emergent airway stabilization, or surgical management. This issue discusses the most common as well as the life-threatening etiologies of acute and chronic stridor and its management in the emergency department.

Case Presentations

A 20-month-old boy is brought into the ED by his mother who is concerned because he woke up with a barky cough and he sounded like he was having difficulty breathing. Prior to tonight, he had 2 days of fever and a runny nose. The mother states that her son's voice sounds more hoarse than usual. The boy’s vital signs are notable for a fever of 39.2°C (102.6°F), a respiratory rate of 60 breaths/min, and a pulse oximetry reading of 98% on room air. He is not in significant acute distress when you walk into the room, but you immediately notice inspiratory stridor at rest, and subcostal retractions. The physical examination is otherwise notable for clear rhinorrhea and transmitted upper airway sounds in the lungs. The nurse asks if you would like to order urgent medications or imaging. Do you give racemic epinephrine and/or dexamethasone immediately? Is a chest x-ray necessary? How long should you observe this patient before deciding on his disposition?

A few minutes later, EMS brings in a 4-year-old boy for stridor and drooling. Per the paramedics' report, he’s had 6 days of rhinorrhea and cough, followed by fever for the past 2 days. Tonight, his mother called 911 when he started drooling at the dinner table and would not participate in the family’s conversation. On EMS arrival, he is febrile to 40°C (104°F), his respiratory rate is 44 breaths/min, and he has a pulse oximetry reading of 92% on room air. The EMS team started supplemental oxygen via facemask and attempted to place a peripheral IV catheter, without success. On ED arrival, the boy is sitting up on the stretcher, unwilling to move. You ask him his name, but he just looks at you and doesn’t answer. The collar of his shirt is wet from drooling, and he looks afraid. At this point, what initial steps should be taken? Should you make another attempt to obtain IV access? Is imaging necessary?

Near the end of your shift, a 3-month-old girl is brought into the ED by her parents for noisy breathing while feeding tonight. She was born at 34 weeks and has had several visits to her pediatrician for intermittent stridor and noisy breathing that started approximately 1 month after birth. She has been treated multiple times for croup over the past 4 weeks. On examination, she is very active and well-appearing, with intermittent stridor. She has no retractions or tachypnea, and her vital signs are all within normal limits. What additional questions on history would aid in making the diagnosis? How will you confirm a diagnosis in this patient? Is imaging useful in this scenario?

Introduction

Respiratory distress is one of the most common reasons children present to the emergency department (ED), accounting for 10% of visits.¹ Life-threatening airway emergencies are often secondary to obstruction and must be recognized quickly. Upper airway obstruction in children can range from partial to complete, and often presents with stridor, a high-pitched breath sound produced by turbulent air-flow through a partially obstructed airway. Stridor can be acute or chronic, and acquired or congenital. Because stridor is a sign and not a diagnosis, the underlying etiology must be identified to guide management.^2,3 In the ED, identifying severe and life-threatening causes of stridor and acting quickly are crucial to preventing respiratory failure.

The cause of upper airway obstruction can often be identified through history and physical examination alone. The age of the child is an important consideration. While chronic and congenital etiologies of stridor are more common in neonates and infants aged < 6 months, acute infectious etiologies are more prevalent in older infants and children.⁴ The most common cause of acute stridor in children presenting to the ED is croup; the most common cause of chronic stridor is laryngomalacia.^5,6

The management of upper airway obstructions continues to evolve. The development of the Haemophilus influenzae type B (Hib) vaccine has greatly reduced the number of cases of H influenzae type B epiglottitis. Increased knowledge regarding intubation of neonates has led to a dramatic decline in acquired subglottic stenosis, and technological advances in endoscopic airway visualization have revolutionized surgical management of pediatric airways.⁷

This issue of Pediatric Emergency Medicine Practice focuses on the etiology, diagnosis, and management of upper airway obstruction in the ED, specifically, the most common and life-threatening etiologies of acute and chronic stridor. Prompt recognition and appropriate treatment of stridor in the ED are key to recovery for children with upper airway obstruction.

Critical Appraisal of the Literature

A literature search was performed in PubMed using the terms stridor, upper airway obstruction, croup, epiglottitis, bacterial tracheitis, mononucleosis, foreign body, anaphylaxis, biphasic reaction, airway burns, thermal burns, laryngomalacia, subglottic stenosis, vocal cord paralysis, vocal cord dysfunction, respiratory papilloma, subglottic hemangioma, vascular rings, and bronchogenic cysts. The search was filtered for patients aged 0 to 18 years. A total of 193 articles published from 1988 to the present were reviewed. The Cochrane Database of Systemic Reviews was searched using the terms stridor and upper airway obstruction; 14 reviews were identified, with 3 of them pertinent to this article. The American Academy of Pediatrics (AAP) and National Guideline Clearinghouse (www.guideline.gov) were also searched, but there are no official guidelines or clinical algorithms relevant to the scope of this article.

The majority of studies on stridor are retrospective chart reviews, with very few randomized controlled trials or prospective studies. Much of the focus on newer research on stridor and upper airway obstruction has been on the treatment of croup with steroids and nebulized epinephrine. Because many acute causes of stridor—especially those that are life-threatening—are rare in pediatric patients, many of the articles on these topics consist of case reports and case series. High-quality pediatric studies are still needed on the topic of upper airway obstruction, as many clinical questions remain unanswered.

Risk Management Pitfalls for Management of Children With Stridor

1. “We must start an IV and get labs now!”

Children with stridor should be left in positions of comfort, with as little manipulation as possible. Agitating the patient with supplemental oxygen, unnecessary intravenous access, and blood work can lead to worsening respiratory distress; these interventions should be reserved for patients who require parenteral therapy or are deteriorating after history and physical examination.

2. “I didn't want to waste time observing a patient with stridor.”

Observation is important in guiding initial management and can provide a significant amount of information almost immediately. Watching for increased work of breathing and drooling after placing the patient in a position of comfort can determine necessary initial interventions.

3. “This must be croup. The patient is a 26-month old with stridor.”

All stridor is not croup. When a patient is not responding to initial management, consider other less common etiologies.

4. “The child looks comfortable now, so he must be out of the woods.”

Do not underestimate the potential for rapid deterioration in children with stridor. In cases of acute stridor, the airway can be quickly obstructed, so it is important to remain vigilant in monitoring these patients after treatment is initiated.

5. “The chances we will need an emergent airway are pretty small, so let’s just watch and wait.”

Failure to plan ahead and prepare for an advanced airway can result in morbidity and mortality. If there is the possibility that an emergent airway will be needed, ensure the necessary equipment is available and essential personnel are notified.

6. “The child responded to corticosteroids almost immediately, so he is safe for discharge now.”

Steroids do not work immediately. Remain vigilant and take advantage of the observation period. A child can deteriorate after the initial response and may need further interventions.

7. “We should give antibiotics just in case this isn’t viral croup.”

Most well-appearing children with acute stridor will have croup, which is most likely viral and should not be treated with antibiotics. Antibiotics are warranted in cases of epiglottitis, bacterial tracheitis, peritonsillar abscess, and retropharyngeal abscess.

8. “The child needs a CT scan, so he must go off the floor.”

Be judicious in determining which patients are stable enough to leave the ED for diagnostic testing. Consider how the testing will change management acutely.

9. “The patient is up-to-date on all vaccines, so this can’t be epiglottitis.”

The epidemiology of epiglottitis is changing and is often seen in fully immunized patients. Do not rule out the diagnosis on the basis of vaccine status.

10. “We should probably get an x-ray to confirm that this is croup.”

Many cases of stridor are diagnosed clinically and do not require diagnostic testing for confirmation. Additionally, radiographic findings for croup lack sensitivity and specificity.

Tables and Figures

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study, such as the type of study and the number of patients in the study is included in bold type following the references, where available. The most informative references cited in this paper, as determined by the author, are noted by an asterisk (*) next to the number of the reference.

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