ENT JC086: Upper Airway Obstruction And Tracheostomy Flashcards
Upper airway obstruction in Neonate / Infant
Causes:
Congenital
1. **Laryngomalacia
2. **Vocal cord palsy
3. **Subglottic stenosis
4. Congenital tumour, cyst
5. **Subglottic haemangioma
6. Vascular + Lymphatic malformation
7. Tracheal anomaly
8. **Craniofacial abnormalities (syndromal causes)
9. **Choanal atresia
Clinical presentation:
1. **Stridor
2. Stertor (i.e. Snoring)
3. **Choking
4. Frequent aspiration
5. Voice change: Hoarseness, **Weak cry, No cry
6. Respiratory distress: ↑ RR, **Insucking (suprasternal, intercostal, subcostal region), Accessory muscles, ↓ Air entry
Stridor
- Important sign for ***upper airway obstruction
- High-pitched, harsh sound
- ∵ Turbulent airflow through partially obstructed airway —> noisy breathing
- Inspiratory: Supraglottic, Vocal cord
- Expiratory: Trachea, Bronchi
- Biphasic (Inspiratory + Expiratory): Subglottis, Trachea
History taking of paediatric airway obstruction
Unstable patients: Immediate resuscitation + Intubation
Stable: History taking
History taking:
1. Perinatal history
2. Birth history
3. **Age of onset
4. Aggravating factors (e.g. worse during feeding)
5. Voice, Cry
6. **Choking on feeding
7. History of intubation (post-intubation traumatic subglottic stenosis)
P/E of paediatric airway obstruction
- Quality of stridor
- RR
- Signs of respiratory distress
- **Intercostal, Suprasternal, Subcostal insucking
- **Nasal flaring - Agitation
- Fatigue
- ↓ Consciousness (late sign)
- Fever
- ***Cyanosis (or cyanotic spell)
- Position of child (e.g. acute epiglottitis, retropharyngeal abscess)
- ***Craniofacial anomaly
- Neck swelling
- Cutaneous haemangioma
- Auscultation
Investigations of paediatric airway obstruction
- ***AP + Lateral neck X-ray
- CXR
- Endoscopy
- **Flexible laryngoscopy (NA/LA)
- **Rigid laryngoscopy (GA)
- Ventilating bronchoscopy (GA)
- Microlaryngoscopy + CO2 laser - CT virtual bronchoscopy
- MRI / MR angiography (look at great vessels in mediastinum)
Flexible laryngoscopy vs Rigid laryngoscopy vs Ventilating bronchoscopy
Flexible laryngoscopy:
- ***Dynamic assessment of larynx
—> Vocal cord mobility, Coordination of larynx, Laryngomalacia (cause prolapse of supraglottis)
- done awake / under LA
Rigid laryngoscopy / Laryngotracheobronchoscopy (LTB):
- More detailed examination of larynx, vocal cord, ***trachea
- done under GA
- for more severe stridor
—> severe stridor
—> biphasic stridor
—> desaturation / cyanotic spell
—> failed extraction for 3 times
—> frequent aspiration / choking
—> failure to thrive
—> XR suggestive of subglottic / tracheal obstruction
—> clinical suspicion e.g. previous intubation, cutaneous haemangioma
Ventilating bronchoscopy:
- for severe distress patient requiring anaesthetic agent during airway examination
- **bypass obstruction for difficult intubation
- **removal of foreign body in trachea
- Laryngomalacia
- 軟喉症
- Inward prolapse of arytenoids —> obstruction of larynx
- 70-80% Stridor in infant
- M:F = 2:1
- presents within first ***2 weeks of life
Clinical features:
- Inspiratory stridor
- **Normal cry
- **No cyanosis
- Worsen on supine position, improves in prone, sitting, hyperextension of neck
- Feeding difficulties (e.g. choking)
Natural course:
- **Self-limiting
- **Resolution by 12-18 months
Complications:
- OSA
- ***Failure to thrive
- Cor pulmonale
- Chest deformity
Treatment:
- ***CO2 Supraglottoplasty / Laser aryepiglottoplasty
- Vallecula and Laryngeal cyst
- Stridor in neonate
- Presented with respiratory distress
- GA for excision
- Subglottic stenosis
Definition:
- Full term infant: Subglottic diameter <4 mm
- Preterm: Subglottic diameter <3.5 mm
Stenosis:
- Membranous vs Cartilaginous
- **Congenital (abnormal cricoid ring) vs **Acquired (post-intubation)
Grading of Subglottic stenosis: **Laryngotracheobronchoscopy (i.e. Rigid bronchoscopy)
- Size the airway with ET tube (largest tube with air leak at 25 cmH2O)
- **Cotton-Myers classification:
—> Grade 1: <50% obstruction
—> Grade 2: 50-70%
—> Grade 3: 71-99%
—> Grade 4: 100%
Treatment:
1. **CO2 laser
2. Balloon dilatation
3. **Laryngotracheal reconstruction (LTR) (definitive: for abnormal cricoid ring)
- Bilateral vocal cord palsy
Congenital
- Stridor shortly **after birth
- **Weak cry / no cry
- Choking
- Idiopathic
- Need to rule out ***CNS pathology e.g. Arnold-Chiari malformation (abnormal herniation of cerebellum)
Acquired
- Post-cardiac, lung, thyroid surgery (Recurrent laryngeal nerve damage)
Treatment:
1. Treat underlying cause
2. Conservative
3. **Bilateral: 50% tracheostomy
4. **Congenital palsy majority recover at 2-5 yo
5. Definitive surgery after adolescence: Lateralisation / Arytenoidectomy
Unilateral vocal cord palsy
- Post-cardiac, Post-thyroid surgery
- Majority have good compensation by other cord
- **Speech therapy
- **Medialisation of vocal cord
- Injection laryngoplasty
- Subglottic haemangioma
- Mass (Haemangioma) below vocal cord
- Symptomatic by ***3 months
- Inspiratory (Supraglottic, Vocal cord) to Biphasic stridor (Subglottis, Trachea)
- ***Recurrent croup
- 50% cutaneous haemangioma
Treatment:
1. **Systemic steroid (to shrink haemangioma)
2. CO2 laser (for obstruction)
3. **Propranolol (to shrink haemangioma)
4. Tracheostomy (for circumferential haemangioma)
5. α2 interferon
- Laryngeal cleft
Congenital midline defect of posterior larynx, trachea, anterior wall of esophagus due to ***Incomplete formation of tracheoesophageal septum
- **Benjamin-Inglis classification:
- Type 1-4
Treatment:
- Endoscopic repair of laryngeal cleft
- Congenital disorder of trachea
- Tracheomalacia
- Vascular compression of trachea (by great vessels)
- Tracheal stenosis (e.g. post-intubation): Balloon dilatation vs Tracheoplasty
- Congenital head and neck tumours
E.g. Teratoma
- Lymphatic malformation
- ***Cystic hygroma
- 60% at birth
- 75% in head and neck region (others e.g. axilla)
Treatment:
- Surgical excision
- Injection ***OK432 (attenuated strain of Streptococcus pyogenes) —> shrink cystic hygroma
- Vascular anomaly
- Vascular ring (e.g. Double aortic arch)
- Aberrant subclavian artery
- Aberrant pulmonary artery
- Extrinsic compression of trachea
- Craniofacial abnormalities
- Pierre Robin syndrome
- Treacher Collin syndrome
- ***Apert syndrome
- Crouzon syndrome
Manifestations:
1. **Hypoplastic mandible —> Mandibular distraction
2. **Hypoplastic maxilla
3. **Retrognathia (small receding chin)
4. **Choanal atresia
- 1:8000 live birth
- F:M = 2:1
- **Failure of breakdown of buccopharyngeal membrane —> obstruction at back of nasopharynx
- Unilateral:Bilateral = 3:2
- Bilateral: ENT emergency —> ∵ Neonates are **obligate nasal breather
- Treatment: Transnasal opening of atresia
Causes of Upper airway obstruction in Toddlers / OIder Children
Infective
1. **Croup
2. **Epiglottitis
3. Retropharyngeal abscess
Others:
1. Recurrent respiratory papillomatosis (benign tumors (papilloma) form along the aerodigestive tract)
2. Obstructive sleep apnea
3. ***Foreign body ingestion
- Croup
aka Laryngotracheobronchitis
- **Subglottic
- 6 months - 3 yo (peak at 2 yo)
- Recurrent croup need to rule out underlying **subglottic stenosis
Causative agents:
1. **Parainfluenza virus
2. **Influenza virus type A
3. ***RSV
4. Mycoplasma pneumoniae
Clinical features:
- Preceded by URTI
- Hoarseness
- ***Barking cough
- Biphasic stridor
Investigations:
- X-ray (***Steeple sign)
Treatment:
1. Close observation
2. 5-10% will need admission
3. **Systemic steroid
4. **Nebulised adrenaline
5. Intubation
- Acute epiglottitis
**ENT + Paediatric emergency
- **Supraglottic
- 2-6 yo (peak at 3-4 yo)
Causative agents:
1. ***Hib
2. β-haemolytic Streptococcus
3. Pneumococcus
4. Staphylococcus
Clinical features:
- Rapidly worsening sore throat
- High fever
- **Inspiratory stridor
- **Drooling
- ***Unable to speak / Muffled “hot potato” voice
- Tripod sign
Investigation:
- X-ray (***Thumb sign) (ONLY do x-ray when stable)
Treatment:
1. Keep calm
2. NO attempt for throat exam, blood taking, IV access
3. Diagnosis by **history
4. Bring patient to **OT
5. Inform senior paediatrician, ENT, anaesthetist
6. Gaseous induction followed by **intubation to secure airway
7. Blood culture + Set up IV line
8. **3rd gen Cephalosporin
Epiglottitis vs Croup
Acute epiglottitis (**Supraglottic):
- **Haemophilus influenzae type B
- 2-4 years
- toxic and unwell
- abrupt onset
- high fever
- minimal/absent cough
- **unable to speak
- **drooling saliva
Croup (**Subglottic):
- **VIRUS
- 3 month - 3 years
- well looking
- **viral prodrome
- moderate fever
- **barking cough
- hoarse voice
- ***able to swallow
- Retropharyngeal abscess
- Commonest deep neck infection in <4 yo
- caused by Infected retropharyngeal LN (∵ retropharyngeal LN disappear in adult —> parapharyngeal abscess)
Clinical features:
- **Mimic croup
- History of URTI
- Toxic, fever
- Head hyperextended, stiff neck
- **Inspiratory stridor
- Dysphagia, drooling
Investigations
- X-ray (↑ Retropharyngeal space)
- Recurrent respiratory papillomatosis (RRP)
Mean age of presentation: 2 yo
Causative agents:
- **HPV 6, 11
- Mother infected with **genital warts —> transmitted during delivery
Clinical features:
- Papilloma can occur from **lips to **lungs
Treatment:
1. Laryngeal debrider
2. ***CO2 laser
- Foreign body
- common between 1-3 yo
Accurate history:
- Witness
- Choking episodes, coughing spells, aspiration
Clinical features:
- Variable S/S
- **Stridor + **Wheeze
- Auscultation: Unilateral ***decrease air entry, Wheezing
Investigations:
- CXR: **Hypoinflation of inspiration, **Hyperinflation on expiration (air-trapping) (but 25-50% normal CXR)
