Stridor

Related Subjects: |Acute Epiglottitis |Croup |Acute Tracheitis |Stridor

🚨 Stridor suggests impending upper airway obstruction — airway management is the absolute priority. ➡️ Fast bleep anaesthetics + ENT immediately. ⚠️ Never leave the patient unattended.

🌬️ About

• Stridor = high-pitched harsh sound from turbulent airflow due to partial obstruction.
• Inspiratory stridor → usually extra-thoracic (e.g. larynx, pharynx).
• Expiratory stridor → usually intra-thoracic (e.g. trachea).
• Biphasic stridor → fixed obstruction (foreign body, tumour, subglottic stenosis).

🧾 Causes

• Inspiratory: Croup, Epiglottitis, Bacterial tracheitis, Retropharyngeal/peritonsillar abscess, Laryngomalacia, Anaphylaxis, Vocal cord palsy.
• Expiratory: Tracheal stenosis, Bacterial tracheitis, Anaphylaxis.
• Biphasic: Foreign body, Subglottic stenosis, Haemangioma, Tumour/mass.

🩺 Clinical Features

• Signs of obstruction: stridor, tachypnoea, chest retractions, drooling 🤤, trismus, dysphagia, tripod/"sniffing" position.
• Stridor + fever + rapid progression = 🚨 think Epiglottitis or Bacterial tracheitis.
• Afebrile with sudden onset = ⚠️ Foreign body, Anaphylaxis, or thermal injury.
• Slow progressive stridor + weight loss/cachexia = 💭 Tumour.

💊 Management

• 🏥 ABC + 15 L/min O₂ (humidified). Continuous monitoring.
• 👀 Do NOT examine throat in suspected epiglottitis → wait for senior airway support.
• 🪑 Keep patient upright, minimise distress.
• 🍴 Foreign body: choking algorithm (back blows, Heimlich). If persistent, airway inspection.
• 🌬️ Heliox (80:20 He:O₂) can reduce work of breathing if available.
• 💉 Adrenaline 0.5 mg IM if anaphylaxis (repeat if needed). 💨 Nebulised adrenaline (1–5 ml 1:1000) for acute obstruction.
• 📞 Immediate anaesthetic + ENT referral if deteriorating. Expect difficult intubation (smaller ETT). If unable → “front of neck airway” (scalpel–bougie cricothyroidotomy).
• 💊 Dexamethasone 8 mg IV for inflammatory/anaphylactic/malignant causes.
• 📊 Once stable: CXR + bloods. Definitive: • Tumour → radiotherapy ± laser/stenting • Severe fixed obstruction → ENT intervention • End-stage/no options → comfort + palliative measures

🔴 Red Flags (Think Epiglottitis)

• Drooling + tripod posture
• Sudden onset, high fever
• Toxic, very unwell child/adult
• NEVER attempt throat exam until airway secure

📚 References

• Resuscitation Council UK – Airway Emergencies
• ENT UK – Guidelines for Acute Stridor

Cases — Stridor

• Case 1 — Acute Epiglottitis (Emergency) 🚨: A 7-year-old child presents with sudden onset fever, sore throat, drooling, and inspiratory stridor. Sitting forward, unable to swallow, muffled “hot potato” voice. Diagnosis: Acute epiglottitis. Management: Do not examine throat; call anaesthetics/ENT urgently; secure airway in theatre; IV antibiotics (e.g., ceftriaxone).
• Case 2 — Laryngeal Tumour (Subacute) 🎭: A 62-year-old man, heavy smoker, develops progressive hoarseness and noisy breathing over months. Exam: biphasic stridor, palpable cervical lymphadenopathy. Diagnosis: Stridor due to obstructing laryngeal carcinoma. Management: Urgent ENT referral; flexible laryngoscopy; secure airway if compromised; oncological treatment (surgery, radiotherapy).
• Case 3 — Anaphylaxis (Rapid Onset) 🐝: A 30-year-old woman stung by a wasp develops facial swelling, inspiratory stridor, urticaria, and hypotension (BP 75/40). Diagnosis: Stridor due to upper airway oedema in anaphylaxis. Management: IM adrenaline 0.5 mg immediately; high-flow O₂; IV fluids; IV hydrocortisone + chlorphenamine; airway team standby for intubation/tracheostomy.

Teaching Commentary 🧠

Stridor = upper airway obstruction, turbulent flow on inspiration (often extrathoracic). - Acute causes: epiglottitis, anaphylaxis, croup, foreign body. - Subacute/chronic causes: laryngeal cancer, vocal cord palsy, tracheal stenosis. Always assess with ABCDE, call anaesthetics/ENT early, and never delay securing the airway in life-threatening cases. Oxygen, nebulised adrenaline, or heliox can be used as temporising measures while definitive management is arranged.