Study guide
4.1 Upper Airway Obstruction
AHA PALS Provider Pediatric Advanced Life Support
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1 Chapter 1: Course Overview & Exam Logistics
1.1 Current Exam Facts 1.2 Audience, Prerequisites & Study Plan
2 Chapter 2: Systematic Pediatric Assessment
2.1 Pediatric Assessment Triangle (PAT) 2.2 Evaluate–Identify–Intervene Sequence 2.3 Primary Assessment: ABCDE 2.4 Secondary Assessment, SAMPLE & Vitals by Age
3 Chapter 3: Respiratory Distress & Failure
3.1 Respiratory Distress vs Failure 3.2 Recognition & Immediate Intervention Priorities 3.3 Oxygen Delivery & Basic Airway Support
4 Chapter 4: Airway Problems & Ventilation Strategies
4.1 Upper Airway Obstruction 4.2 Lower Airway, Lung Tissue Disease & Disordered Control 4.3 Bag-Mask Ventilation & Advanced Airways During CPR
5 Chapter 5: Shock Fundamentals & Hypovolemia
5.1 Compensated vs Hypotensive (Decompensated) Shock 5.2 Hypovolemic Shock 5.3 Isotonic Fluid Bolus 10–20 mL/kg & Reassessment
6 Chapter 6: Distributive, Cardiogenic & Obstructive Shock
6.1 Distributive & Septic Shock Pathway 6.2 Cardiogenic Shock 6.3 Obstructive Shock
7 Chapter 7: Pediatric BLS & High-Quality CPR
7.1 High-Quality CPR Metrics 7.2 Compression-Ventilation Ratios 7.3 CPR Quality Monitoring: ETCO2 & Diastolic BP
8 Chapter 8: Pediatric Cardiac Arrest Algorithm
8.1 Arrest Recognition & Systematic Approach 8.2 VF/pVT & Defibrillation Energy 8.3 Asystole & PEA 8.4 Epinephrine in Arrest: Dose & Timing
9 Chapter 9: Bradycardia & Narrow-Complex Tachycardia
9.1 Bradycardia with Poor Perfusion 9.2 Sinus Tachycardia vs SVT 9.3 Stable SVT: Vagal Maneuvers & Adenosine
10 Chapter 10: Unstable Tachycardia & Wide-Complex Rhythms
10.1 Unstable Tachycardia & Synchronized Cardioversion 10.2 Wide-Complex Tachycardia & VT with Pulse 10.3 Antiarrhythmics for Tachycardia with Pulse
11 Chapter 11: Reversible Causes & Special Circumstances
11.1 Reversible Causes: The H's and T's 11.2 Special Circumstances at Exam Level 11.3 Extracorporeal CPR (ECPR) Overview
12 Chapter 12: Post–Cardiac Arrest Care
12.1 Post-ROSC Oxygenation & Ventilation 12.2 Post-Arrest Hemodynamic Support 12.3 Temperature Control & Glucose 12.4 Neuroprognostication & Transport
13 Chapter 13: Vascular Access & Core Pharmacology
13.1 IV and Intraosseous Access 13.2 Epinephrine Dosing in Depth 13.3 Amiodarone, Lidocaine & Adenosine 13.4 Weight-Based Dosing Aids & Drugs to Avoid Routinely
14 Chapter 14: Team Dynamics & Megacode Readiness
14.1 High-Performance Team Roles 14.2 Closed-Loop Communication 14.3 Constructive Intervention, Debriefing & Exam Integration
4.1 Upper Airway Obstruction
Key Takeaways Explain This Topic AI
Upper-airway obstruction produces inspiratory stridor, a prolonged inspiratory phase, and often a barky cough or voice change; lower-airway disease more often produces expiratory wheeze and prolonged expiration.
Croup care includes keeping the child calm, oxygen when indicated and corticosteroid treatment; moderate or severe croup also warrants nebulized epinephrine and observation. Humidified mist has no demonstrated benefit.
2025 foreign-body airway obstruction (FBAO): infants receive 5 back blows + 5 chest thrusts; children receive 5 back blows + 5 abdominal thrusts; if unresponsive, start CPR, remove only a visible foreign body, and never perform blind finger sweeps.
Anaphylaxis with airway involvement is treated first with intramuscular epinephrine; airway support and oxygen follow—do not delay epinephrine for IV access or antihistamines alone.
Distinguish complete from partial obstruction: effective cough means encourage coughing; ineffective cough, inability to speak/cry, or cyanosis means immediate relief maneuvers.
Last updated: September 2026
Upper vs Lower Airway Obstruction: Clinical Discrimination
Respiratory emergencies are a core PALS course area, and recognizing whether obstruction is above or below the thoracic inlet guides therapy. Anatomy drives the sounds and the therapy. The upper airway (nose, pharynx, larynx, and extrathoracic trachea) is a narrow tube; small decreases in caliber produce large increases in resistance (Poiseuille’s relationship). The lower airways (intrathoracic trachea, bronchi, bronchioles) narrow further on expiration, so small-airway disease lengthens the expiratory phase.
Exam-level contrast table
- Feature Upper-airway obstruction Lower-airway obstruction
- Typical sound Inspiratory stridor (high-pitched) Expiratory wheeze
- Phase most affected Inspiration prolonged Expiration prolonged
- Voice / cough Hoarse, barky (croup), muffled (epiglottitis rare) May be normal voice; cough often tight
- Preferred posture Sniffing / upright; tripoding if severe May sit forward; less classic "sniff"
- Classic examples Croup, FBAO, anaphylaxis (laryngeal edema), bacterial tracheitis Asthma, bronchiolitis
Immediate focus Keep airway calm/open; relieve obstruction; IM epi if anaphylaxis Oxygen, bronchodilators, assist ventilation if failing
Stridor is turbulent flow through a narrowed extrathoracic airway and is classically inspiratory . Wheeze is lower-airway narrowing and is classically expiratory . Real children can have mixed findings (for example anaphylaxis affecting both larynx and lower airways), but the exam expects you to pick the dominant pattern and the matching first intervention.
Severity signals that apply to any upper-airway problem
Partial obstruction with effective cough and ability to cry/speak → support, oxygen if needed, allow the child to clear if possible.
Ineffective cough , silent or weak cry, cyanosis, or progressive lethargy → emergency obstruction pathway (FBAO maneuvers or advanced airway support depending on cause).
Drooling, tripod posture, and toxic appearance raise concern for severe infectious obstruction—minimize agitation and prepare for difficult airway with expert help.
Croup (Laryngotracheobronchitis)
Croup is the most common infectious upper-airway obstruction in toddlers. Viral inflammation (often parainfluenza) narrows the subglottic trachea. The classic history is a young child with a preceding upper respiratory infection who develops a barking/seal-like cough , hoarse voice, and inspiratory stridor , often worse at night.
Clinical picture on the PAT and primary assessment
Appearance: May be anxious but usually interactive unless severe or failing.
Work of breathing: Tachypnea, stridor, suprasternal retractions; severity tracks with stridor at rest and degree of effort.
Circulation to skin: Usually normal early; cyanosis is late.
Severity framing used on exams:
Mild: Barky cough, minimal or no stridor at rest, little work of breathing.
Moderate: Stridor at rest, moderate retractions, still interactive.
Severe: Marked stridor, severe retractions, agitation or fatigue, hypoxia—this is upper-airway obstruction with high risk of failure.
Impending failure: Quiet breathing after severe effort, lethargy, poor air entry, bradycardia.
Management priorities (exam level)
Keep the child calm. Agitation worsens dynamic obstruction. Allow preferred posture; avoid forced examination of the throat if the child is severely obstructed.
Oxygen as needed for hypoxemia or significant distress (blow-by if a mask increases agitation).
Give corticosteroid treatment for croup according to the clinical protocol. Humidified mist has no demonstrated benefit and is not recommended as treatment.
Nebulized epinephrine (often racemic epinephrine) when there is stridor at rest or moderate-to-severe obstruction. Epinephrine reduces laryngeal mucosal edema via α-adrenergic vasoconstriction. Observe after dosing for recurrence of stridor or distress as the effect wears off.
Corticosteroids (commonly dexamethasone in clinical practice) reduce inflammation and are standard for croup; PALS vignettes may mention steroid therapy as part of definitive medical care after acute airway support.
If respiratory failure develops—inadequate effort, severe hypoxia, progressive lethargy— open the airway and provide bag-mask ventilation with oxygen; prepare for advanced airway with anticipated difficulty and call for the most experienced airway clinician available.
Differentials the exam may contrast
Foreign body: Sudden onset during eating or play, may lack viral prodrome.
Anaphylaxis: Rapid onset with urticaria, angioedema, wheeze, hypotension.
Epiglottitis / bacterial tracheitis: Toxic appearance, high fever, drooling (epiglottitis), or toxic child with croup-like picture that worsens—rare but high stakes; do not agitate; early airway expertise.
Do not confuse mild croup (calm care and corticosteroid treatment) with severe obstruction needing nebulized epinephrine and possible assisted ventilation.
Loading diagram... Upper Airway Obstruction Decision Map (PALS Exam Level)
Foreign-Body Airway Obstruction (FBAO) — 2025 AHA/AAP Updates
Foreign-body aspiration is a classic sudden-onset upper-airway emergency. Suspect FBAO when a previously well child develops acute coughing, gagging, stridor, or inability to speak or cry during eating or play—especially with small objects, nuts, grapes, or hot dogs.
Responsive child: complete vs partial obstruction
Status Findings Action
Mild / partial Effective cough, can cry or speak, good color early Do not interfere with forceful coughing; position of comfort; oxygen if needed; ready to escalate
Severe / complete Ineffective or silent cough, inability to speak/cry, cyanosis, progressive distress Immediate relief maneuvers by age
2025 relief sequences (must memorize)
Infants (<1 year):
Deliver 5 back blows (infant face-down along forearm, head lower than chest, blows between scapulae with heel of hand).
Turn infant face-up and deliver 5 chest thrusts using the heel of one hand on the infant’s sternum, following the 2025 infant FBAO technique.
Repeat cycles of 5 back blows + 5 chest thrusts until the object is expelled or the infant becomes unresponsive.
Do not use abdominal thrusts in infants —risk of solid-organ injury.
Children (≥1 year):
Deliver 5 back blows (lean child forward; heel of hand between scapulae).
Deliver 5 abdominal thrusts (Heimlich-type: fist above navel, upward thrusts).
Alternate 5 back blows + 5 abdominal thrusts until the object is expelled or the child becomes unresponsive.
The 2025 emphasis on combining back blows with thrusts for children (not thrusts alone as the only remembered step) is a high-yield update relative to older single-maneuver mental models. Match the sequence to age on every vignette.
If the child becomes unresponsive
Start CPR immediately (begin with chest compressions as for cardiac arrest/BLS).
Each time the airway is opened for breaths, look in the mouth —if you see a foreign body, remove it.
Never perform blind finger sweeps —you may push the object deeper or cause injury.
Attempt ventilation when indicated by the BLS sequence; if the chest does not rise, reposition and continue CPR with checks for a visible object.
Activate emergency response / ALS backup early.
Link to PALS advanced care
After relief, reassess ABCs. Residual wheeze or focal findings may indicate a remaining distal foreign body needing imaging and specialty care. If obstruction cannot be relieved and the child remains critically ill, advanced airway attempts and surgical airway readiness may be required in real systems—exam focus stays on correct BLS FBAO sequence and no blind sweeps.
Anaphylaxis with Airway Involvement
Anaphylaxis is a rapid, multi-system allergic reaction that can obstruct the upper airway (laryngeal edema, tongue swelling) and constrict lower airways (bronchospasm) while causing distributive shock. Triggers include foods (peanut, tree nut, shellfish, milk), insect stings, medications, and latex.
Recognition clues
Acute onset after exposure (minutes to a few hours).
Skin/mucosal signs: urticaria, flushing, angioedema of lips/tongue/face.
Respiratory: stridor, hoarseness, drooling, wheeze, dyspnea, hypoxia.
Circulatory: tachycardia, hypotension, poor perfusion (may present as shock).
GI: vomiting, crampy pain (supportive of multi-system involvement).
Not every case has a full rash. Airway and circulation findings alone can still be anaphylaxis when the history fits.
First-line therapy
Intramuscular epinephrine in the mid-outer thigh immediately —this is the definitive first-line drug. Do not delay IM epinephrine to start an IV, give antihistamines alone, or "watch the rash."
Position of comfort; if hypotensive, supine with legs elevated when feasible (avoid forcing flat if severe respiratory distress requires upright posture—use clinical judgment).
High-flow oxygen and airway support; prepare for bag-mask and difficult airway if edema progresses.
Rapid IV/IO access after epinephrine for fluid boluses if shock is present (isotonic crystalloid per shock algorithms).
Adjuncts (antihistamines, bronchodilators for wheeze, corticosteroids) are secondary —they do not replace epinephrine.
Observe for biphasic recurrence; prepare for repeat IM epinephrine if symptoms return.
Exam traps
Choosing diphenhydramine or steroids as the first drug when airway/breathing/circulation are threatened.
Confusing isolated mild urticaria with anaphylaxis—but when stridor, respiratory distress, or hypotension is present, treat as anaphylaxis.
Forgetting that anaphylaxis can present with both upper-airway stridor and lower-airway wheeze; epinephrine still comes first.
Clinical scenario (synthesis)
A 4-year-old develops facial swelling, inspiratory stridor, and wheezing minutes after a peanut exposure. The child is anxious with retractions; SpO2 is 91% on room air. This is anaphylaxis with upper- and lower-airway involvement. Immediate action: IM epinephrine , oxygen, continuous monitoring, IV access and fluids if perfusion worsens, and readiness to support the airway. Nebulized bronchodilators may help wheeze but are not a substitute for epinephrine. If the child becomes unresponsive with inadequate breathing, a healthcare provider checks for a pulse for no more than 10 seconds. With no definite pulse, start CPR. With a pulse but inadequate breathing, support ventilation at 20–30 breaths/min; start CPR if the heart rate remains below 60/min with poor perfusion despite effective oxygenation and ventilation. This anaphylaxis assessment is distinct from the unresponsive-choking CPR pathway.
Mastering upper-airway patterns—croup, FBAO, anaphylaxis—and matching each to the correct first move is core PALS respiratory content and feeds directly into the ventilation skills in Section 4.3.