STRIDOR IN CHILDREN

By: Maj Vishal Gaurav

Moderator: Dr A Sethi

Definition

Harsh, high-pitched, noisy respiration/musical sound produced by turbulent airflow through partially obstructed upper airway

• Stridor is a symptom/sign, not a diagnosis/ disease

• Always indicative of airway obstruction

• Stertor Low-pitched snoring type

Further Terminology

• Supraglottic obstruction: – Inspiratory stridor (high-pitched)

• Extrathoracic trachea obstruction – includes glottis & subglottis: – Biphasic stridor (intermediate pitch)

• Intrathoracic trachea obstruction: – Expiratory stridor (wheeze)

Physics

• Poiseuille’s Law: Resistance inversely proportional to radius to 4th power

• Bernoulli’s Law: Pressure decreases as velocity increases, causing tendency to collapse

Anatomy

• LARYNX IN CHILDREN– HIGHER– LUMEN SMALLER– MORE ACUTE– EPIGLOTTIS: tubular & less rigid– OTHER LARYNGEAL CARTILAGES: less

rigid

Predictably stridor is more in children

Etiology

• Congenital

– Laryngomalacia

– Subglottic Stenosis

– Laryngeal Web

– Subglottic Haemangioma

– Congenital Vocal Cord Palsy

Etiology

• Inflammatory

– Acute Supraglottitis

– Acute Laryngo-Tracheo-Bronchitis

– Laryngeal Edema

– Amyloidosis

– Scleroma

– Neck Space Infections / Abscess

Etiology

• Neoplastic

– Benign

• Salivary Tumors of Airway

• Haemangioma

• Adenoma

• Fibroma

Etiology

• Neoplastic

– Malignant

• Squamous Cell Carcinoma

• Thyroid Malignancies

• Lymphoma

Etiology

• Traumatic

– Laryngo-Tracheal Trauma

– Iatrogenic

• Thyroid Surgery

• Cardiothoracic Surgery

• Prolonged Intubation

– Thermal Injury

– Smoke Inhalation

Etiology

• Miscellaneous

– Foreign Bodies

– Laryngospasm

– Angioedema

– Tracheomalacia

– Laryngocele

Causes of Laryngeal Inspiratory Stridor

• Congenital– Web– Subglottic stenosis– Cyst– Laryngomalacia– VC Paralysis– Micrognathia– Cleft Larynx– Lymphangioma– Hemangioma

• Acquired– Pyrexial

• Ac Epiglottitis• Ac Laryngitis• Ac L-T-Bronchitis• Diphtheria

– Apyrexial• FB• Injury• Scald• Papilloma

Associated Symptoms

• Dyspnoea– Stridor & Dyspnoea are both manifestations of

airway obstruction; severity of one reflects severity of the other

• Cough– Harsh, barking

• Hoarseness– of speech/ cry

• Deglutition– Stridor increases during feeding– Stidorous infants are poor feeders

History taking

• Continuous (more serious) / Intermittent

• Severity– loudness, cyanosis, apnoea

• Age at onset– Congenital disease , manifest some time after

birth (activity, first URTI)

• Relationship to feeding/crying/exercise– May only be noticeable then

Physical examination

• Signs of increased airway resistance– Flaring of nostrils– suprasternal/intercostal/substernal recession

• Tachypnoea• Cyanosis• Rising Pulse rate• Periods of apnoea• Bronchopneumonia• Emphysema• Bronchiectasis

Radiology

• Plain lat Soft-tissue X-rays– Epiglottis– Subglottis

• X-ray Chest– atelectasis, consolidation, emphysema

• CT scan, MRI

• Barium swallow

Endoscopy

All children with stridor should be

endoscoped

Laryngoscopy• Bronchoscopy• Microlaryngoscopy• Flexible endoscopy – problematic in infants

Documentation

Evaluation of a Case of Stridor

HISTORY

• Onset

• Duration

• Any Cough / Fever / Spasmodic Cough?

• Abnormal cry / Hoarseness

• Any feeding difficulty / Dysphagia?

• Aggravating / Relieving factors

• Related to feeding/ posture?

• Weight loss

Examination

• General Examination

– TPR, Nutrition, Colour

– While Sleeping

– Effect of effort on stridor

– Note quality of cry – Dysphonia?

– Study while feeding

– Change positions and see

• Chest Examination

ENT Examination

• Throat

• Indirect Laryngoscopy

• Video Laryngoscopy

• Flexible Fiberoptic Laryngoscopy

• Neck Examination

Investigations

• If time permits

• Blood Counts, ABG, Electrolytes

• X-Ray Chest (PA), X-Ray Soft Tissue Neck (Lat)

• Fluoroscopy

• Rarely, Ba Swallow, CT Scan

• Direct Laryngoscopy with / without anaesthesia

• Bronchoscopy, if reqd.

• Oesophagoscopy under GA

Laryngomalacia• Most common congenital cause

• Soft supraglottic Lx, decreased inlet

• Long epiglottis, curled

• Short aryepiglottic folds

• Lx suprastructure sucked in during inspiration

• Stridor increased on crying, decreased in prone position

• Disappears by 3rd – 4th year

• Inspiratory stridor without hoarseness suggestive

• Dx following DLS

• Rx - Reassurance

Laryngeal Web

• Generally seen b/w the VC’s anteriorly

• Stridor, aphonia from birth

• If big – early surgery/ Laser

CONGENITAL VOCAL CORD PALSY

Congenital Subglottic Stenosis• If mild – resp infections cause dyspnoea /

stridor

• Dx if subglottic diameter is < 4 mm in a full term neonate

Subglottic Haemangioma

• Increase in size at 3-6 months age

• HPV infection

• Associated cutaneous haemangioma

• Dx FOB or DLS

• Rx Endoscopic surgical removal/ Laser + Adjuvant medical therapy (prolonged steroid adm)

Laryngocoele

• Dilatation of saccule of larynx – extending between the thyroid cartilage and ventricle

• Internal/ External

Principles of Management

• ASSESSMENT OF RESPIRATORY IN SUFFICIENCY

• ASSESSMENT OF THE LIKELY CAUSE

• ESTABLISHING AN AIRWAY

• TREATING THE CAUSE

Management

• Stridor with pyrexia

– Assess quickly

– Humidity, Warmth

– Antibiotics

– Steroids – Inhaled / Parenteral

– Racemic Epinephrine

– If no improvement in few hours hospitalisation

Management

• In hospital

– Assessed by Paed, ENT, Anaes

– Investigations

– Direct Laryngoscopy Intubation (if reqd)

– Alternative Airway

• Tracheostomy

• Cricothyroidotomy

– Treatment of specific cause

Conclusion

• Airway Emergency

• Rapid Assessment

• Treatment of Cause

• Prevent Hypoxia

• Alternative Airway

• Constant Monitoring