What is Croup Syndrome?
Croup is a common, primarily pediatric viral respiratory illness and the most common cause of hoarseness, cough, and acute stridor in febrile children. Its alternative names, acute laryngotracheitis and acute laryngotracheobronchitis, point to where it lands: the larynx and trachea, sometimes extending to the bronchi. The name comes from the Anglo-Saxon kropan or the old Scottish roup, meaning to cry out in a hoarse voice.
Pathophysiology
The viruses spread by direct inhalation of a cough or sneeze, or by contaminated hands touching the eyes, nose, or mouth. The nose and nasopharynx are the entry ports; infection then spreads to the larynx and trachea. Inflammation and edema of the subglottic larynx and trachea, especially near the cricoid cartilage, are the clinically significant lesion. Histologically the area is edematous with cellular infiltration in the lamina propria, submucosa, and adventitia. This narrowing produces the seal-like barky cough, turbulent airflow, stridor, and chest-wall retractions, while edema-limited vocal cord mobility causes the hoarseness.
Statistics and Incidences
Croup is the most common pediatric cause of acute stridor, accounting for about 15% of annual clinic and emergency department visits for pediatric respiratory tract infections. It is mainly a disease of infants and toddlers, peaking at 6 months to 36 months (3 years). In North America incidence peaks in the second year of life, at about 5 to 6 cases per 100 toddlers. It is uncommon after age 6 years but can occur in preteens, adolescents, and rarely adults. The male-to-female ratio is about 1.4:1. It occurs most often in late fall and early winter but can present any time of year, and about 5% of children have more than 1 episode.
Causes
Parainfluenza viruses (types 1, 2, 3) cause about 80% of cases, with types 1 and 2 accounting for nearly 66% (StatPearls). The bacterial pathogen Mycoplasma pneumoniae has been identified in a few cases.
Clinical Manifestations
Croup usually starts with nonspecific respiratory symptoms. It may be preceded by coryza and hoarseness, or by no apparent respiratory signs during the evening. Fever is generally low grade (38 to 39°C) but can exceed 40°C. Within 1 to 2 days the characteristic hoarseness, barking cough, and inspiratory stridor develop, often suddenly, with variable respiratory distress. Symptoms worsen at night, and most ED visits occur between 10 pm and 4 am. Spasmodic (recurrent) croup typically presents at night with sudden croupy cough and stridor.
Assessment and Diagnostic Findings
Croup is primarily a clinical diagnosis based on history and exam. Pulse oximetry is usually within the normal range but helps assess the need for supplemental oxygen and detect worsening compromise (tachypnea, falling saturations). Radiographs can help confirm the diagnosis but are not required in uncomplicated cases.
Medical Management
Treatment depends on the degree of respiratory distress. Corticosteroids reduce laryngeal mucosal edema and the need for salvage nebulized epinephrine, and are warranted even in mild symptoms. Children given nebulized racemic epinephrine in the ED should be observed for at least 3 hours afterward, because of rebound bronchospasm, worsening distress, or persistent tachycardia; discharge only if they are clinically stable with good air entry, baseline consciousness, no stridor at rest, and have received corticosteroids. Heliox, a mix of helium and oxygen (with not less than 20% oxygen) delivered by nasal cannula, mask, or hood, has low viscosity and specific gravity that promote laminar airflow, easing the work of breathing and reducing distress.
Pharmacologic Management
The mainstays are corticosteroids and nebulized epinephrine; steroids help in severe, moderate, and mild croup. Corticosteroids decrease airway edema through their anti-inflammatory effect; a single dose of dexamethasone (typically 0.6 mg/kg) improves symptoms and reduces return visits and hospitalization in croup of any severity (AAFP). Epinephrine stimulates alpha and beta2 receptors, constricting precapillary arterioles to decrease airway edema; because of tachycardia and hypertension risk, it is reserved for moderate to severe disease.
Nursing Management
In mild croup the child may have only a croupy cough and need parental guidance and reassurance, given alertness, minimal distress, good oxygenation, and stable fluid status.
Nursing Assessment
Determining the degree of airway obstruction is the most important part of assessment. Begin while taking the history, observing the child seated on the parent's lap at a non-threatening distance; much can be learned without disturbing the child. Assess respiratory rate, accessory muscle use, tracheal tug, and the presence or absence of central cyanosis. A child who is agitated, tired from the effort of breathing, or showing a decreasing level of consciousness needs close monitoring. Stridor at rest, tracheal tug, chest-wall retractions, and changing respiratory and pulse rates indicate treatment is needed.
Nursing Diagnosis
- Ineffective airway clearance related to thick, tenacious mucus and swelling or spasm of the epiglottis.
- Deficient fluid volume related to decreased ability or aversion to swallowing, fever, and increased respiratory losses.
Nursing Care Planning and Goals
The child maintains a clear, open airway with normal breath sounds, rate, and depth and can clear secretions after treatments and deep breaths; demonstrates increased air exchange; identifies methods to enhance secretion removal and the significance of sputum changes (color, character, amount, odor); and avoids factors that impair airway clearance. The child stays normovolemic, evidenced by systolic BP greater than or equal to 90 mm Hg (or baseline), no orthostasis, HR 60 to 100 beats/min, urine output greater than 30 mL/hr, and normal skin turgor, and the family verbalizes the causative factors and behaviors needed to correct fluid deficit.
Nursing Interventions
Use humidified air. Cool mist from a humidifier, or sitting with the child in a bathroom (not the shower) filled with steam from running hot water, helps minimize symptoms.
Treat fever with an antipyretic such as acetaminophen or ibuprofen.
Encourage fluids. Push oral intake; frozen juice popsicles ease throat soreness.
Teach caregivers to avoid smoking in the home, since smoke worsens the cough.
Elevate the head. An infant can sit in a car seat and an older child can be propped on an extra pillow; do not use pillows with infants younger than 12 months.
Decrease anxiety. Keep young children comfortable in a parent's arms and avoid unnecessary painful interventions, because crying raises oxygen demand and respiratory muscle fatigue can worsen the obstruction.
Monitor vital signs. Watch heart rate (tachycardia), respiratory rate (tachypnea), respiratory mechanics (sternal retractions), and pulse oximetry (hypoxia).
Cool mist was historically the mainstay (hospitals kept "croup rooms"), on the theory that mist moistens secretions, lowers their viscosity, and soothes inflamed mucosa.
Evaluation
Goals are met when the child maintains a clear, open airway with normal breath sounds and respirations and clears secretions; demonstrates increased air exchange; identifies methods to enhance secretion removal and the significance of sputum changes; avoids factors that impair clearance; stays normovolemic (systolic BP greater than or equal to 90 mm Hg or baseline, no orthostasis, HR 60 to 100 beats/min, urine output greater than 30 mL/hr, normal skin turgor); and the family verbalizes the causes and behaviors needed to correct fluid deficit.
Documentation Guidelines
Document breath sounds, presence and character of secretions, and accessory muscle use; the plan of care and teaching plan; responses to interventions and actions performed; progress toward desired outcomes; and modifications to the plan of care.
Frequently Asked Questions
What is croup? Croup is viral inflammation and swelling of the upper airway, centered on the larynx and the subglottic trachea, that produces a harsh barking cough, hoarseness, and inspiratory stridor. It most often affects children 6 months to 3 years old (StatPearls).
What causes croup? Most cases are viral, and parainfluenza viruses cause about 80% of them. The virus spreads through respiratory droplets and contaminated hands, then inflames the larynx and trachea (StatPearls).
What is the most important nursing assessment? Judging the degree of airway obstruction. Watch respiratory rate, accessory muscle use, tracheal tug, stridor at rest, and level of consciousness, and do it without upsetting the child, because crying narrows the airway further and raises oxygen demand.
How is croup treated? A single dose of corticosteroid, usually dexamethasone 0.6 mg/kg, is first-line for croup of any severity. Nebulized epinephrine is added for moderate to severe disease for fast but short-lived relief, so these children are observed for several hours afterward (AAFP).
When should a child with croup get emergency care? When there is stridor at rest, marked chest-wall retractions, rising heart and respiratory rates, drooling, cyanosis, or a child who is tiring or becoming difficult to rouse. These signal worsening obstruction that needs immediate evaluation.
How is croup different from epiglottitis? Croup comes on gradually with a barking cough and is usually viral and mild. Epiglottitis is a rapidly progressive bacterial emergency with high fever, drooling, and no barking cough, and the child often sits forward in a tripod position. Distinguishing them quickly matters because epiglottitis can close the airway.