GC220 Upper Airway Obstruction And Tracheostomy
Upper airway obstruction is a partial or complete blockage of the airway above the tracheal bifurcation that may necessitate tracheostomy—a surgical opening in the anterior tracheal wall—to establish a secure airway and maintain ventilation.
Upper Airway Obstruction and Tracheostomy
Big idea: Upper airway obstruction (UAO) is a life-threatening emergency that spans all age groups — from the neonate with laryngomalacia to the adult with a head-and-neck tumour. The key clinical skill is recognising the signs of airway compromise, understanding the anatomical level of obstruction from the stridor pattern, knowing the age-specific differential diagnoses, and being able to manage patients from basic airway manoeuvres all the way to definitive surgical airway (tracheostomy). This lecture also covers tracheostomy indications, surgical technique, complications, tube selection, and post-operative care.
Learning objectives (from the lecture):
- Identify causes of UAO in neonates/infants, children, and adults
- Recognise clinical presentation of airway obstruction
- Approach to assessment — history, examination, investigations
- Understand congenital airway diseases in detail
- Manage common paediatric UAO emergencies (croup, epiglottitis, retropharyngeal abscess, foreign body, recurrent respiratory papillomatosis)
- Manage adult UAO causes (tumours, deep neck infections, bilateral vocal cord palsy, anaphylaxis, trauma)
- Know indications, technique, complications, tube types, and care of tracheostomy
Core Concepts and Mechanisms
Stridor is a high-pitched sound due to turbulent airflow through a partially obstructed airway. [1]
From first principles: when a tube's lumen narrows, flow velocity increases (Venturi effect), and once Reynolds number exceeds ~2000, laminar flow becomes turbulent, producing audible vibration. In the extrathoracic airway, during inspiration negative intrathoracic pressure is transmitted to the airway, which tends to collapse extrathoracic structures inward — hence extrathoracic obstruction worsens on inspiration (inspiratory stridor). During expiration, positive intrathoracic pressure compresses intrathoracic airways — hence intrathoracic obstruction worsens on expiration (expiratory wheeze). [2]
Phase of Stridor = Level of Obstruction
| Phase | Level | Examples |
|---|---|---|
| Inspiratory | Supraglottis, vocal cord | Laryngomalacia, epiglottitis |
| Biphasic | Subglottis, trachea | Croup, subglottic stenosis |
| Expiratory | Trachea, bronchi | Tracheomalacia, foreign body in bronchus |
This is directly from the lecture and is one of the most commonly tested discriminators. [1]
- Stridor: high-pitched, from laryngeal/tracheal level — implies narrowing of the airway at or below the larynx
- Stertor (snoring): low-pitched, from above the larynx (nasopharynx/oropharynx) — e.g., adenotonsillar hypertrophy, tongue base prolapse [1]
- Neonates are obligate nasal breathers — bilateral choanal atresia is therefore an ENT emergency [1]
- The paediatric airway is narrowest at the cricoid ring (subglottis), not at the glottis as in adults; even 1 mm of mucosal oedema dramatically increases resistance (resistance ∝ 1/r⁴ by Poiseuille's law)
- Cartilage is softer and more collapsible (laryngomalacia)
Causes of Upper Airway Obstruction — Age-Based Classification
Laryngomalacia, Vocal cord palsy, Subglottic stenosis, Congenital tumour/cyst, Subglottic haemangioma, Vascular & lymphatic malformation, Tracheal anomaly, Craniofacial abnormalities, Choanal atresia
Croup, Epiglottitis, Retropharyngeal abscess, Recurrent respiratory papillomatosis, Obstructive sleep apnoea, Foreign body
Tumour, Infection, Bilateral vocal cord palsy, Trauma, Foreign body, Anaphylaxis, Obstructive sleep apnoea
| Feature | Significance |
|---|---|
| Stridor | Key sign of UAO |
| Stertor (snoring) | Suggests obstruction above larynx |
| Choking on intake of milk | Suggests supraglottic/glottic or laryngeal cleft pathology |
| Frequent aspiration, cyanosis | Severe compromise |
| Voice change — hoarseness, weak cry, no cry | Vocal cord pathology (palsy, web) |
| Respiratory distress — suprasternal/subcostal insucking, accessory muscle use, poor air entry, tachypnoea | Objective severity markers |
Approach to Paediatric Airway Obstruction
Unstable patients need immediate resuscitation or intubation [1]
Perinatal history, Birth history, Age of onset, Aggravating factors, Voice/cry, Choking/feeding, History of intubation
Why each matters:
- Perinatal history: maternal infections (HPV → RRP), birth trauma (vocal cord palsy), prematurity (subglottic stenosis from intubation)
- Age of onset: stridor from birth = congenital cause; onset at weeks-months = laryngomalacia or haemangioma; acute onset = infection or foreign body
- History of intubation: acquired subglottic stenosis is the commonest acquired cause of subglottic narrowing
Phase of stridor, Signs of respiratory distress (respiratory rate, suprasternal/subcostal insucking, nasal flaring, agitation, fatigue, decreased consciousness), Fever, Cyanosis, Position of child, Craniofacial anomaly, Neck swelling, Cutaneous haemangioma, Auscultation
Clinical Pearl
50% of patients with subglottic haemangioma have cutaneous haemangioma — always examine the skin! [1]
Individualised: AP & lateral neck XR, CXR, Endoscopy, CT, MRI/MRA
| Investigation | When & Why |
|---|---|
| AP & lateral neck XR | Steeple sign (croup), thumb sign (epiglottitis), retropharyngeal widening (abscess) |
| CXR | Foreign body (hyperinflation), pneumothorax, mediastinal mass |
| Endoscopy | Gold standard for direct visualisation |
| CT with contrast | Deep neck infections/abscesses, tumours, vascular anomalies |
| MRI/MRA | Vascular malformations, lymphatic malformations, soft tissue detail |
| Type | Setting | Purpose |
|---|---|---|
| Flexible laryngoscopy | Awake or under LA | Dynamic assessment of larynx — especially vocal cord mobility and laryngomalacia |
| Rigid laryngoscopy / Laryngotracheobronchoscopy (LTB) | Under GA | Detailed anatomy of larynx, vocal cords, trachea; for severe stridor, failed extubation, subglottic pathology |
| Ventilating bronchoscope | Under GA | Ventilation via side ports during airway examination; bypass obstruction for difficult intubation; foreign body removal |
| Microlaryngoscopy | GA | Airway intervention — can use with CO₂ laser for excision of lesions |
What the airway-instrument slides show: rigid LTB under GA with the scope in the airway; a ventilating bronchoscope set with side ports and length scale — you can ventilate while examining/removing FB, unlike a simple diagnostic flexible look. [1]
Congenital Causes — Detailed Coverage
Commonest cause of stridor in infant — 80%
| Feature | Detail |
|---|---|
| M:F = 2:1 | |
| Onset | First 2 weeks of life |
| Stridor character | Inspiratory stridor during sleep, feeding or throughout the day |
| Feeding | May have choking during feeding |
| Cry | Normal cry, no cyanosis |
| Natural history | Majority self-limiting — grows out by 12-18 months |
| Some infants may deteriorate | Failure to thrive, apnoeas |
Clinical assessment: Good history → PE (stridor characteristics, insucking, respiratory distress) → Growth charts (body weight maintained along or increasing percentile) → duration of each milk intake, choking [1]
Management: Monitor with regular follow-up by Paediatrician or ENT. Severe cases may need supraglottoplasty under GA [1]
Why supraglottoplasty works: In laryngomalacia, the supraglottic tissues (omega-shaped epiglottis, short aryepiglottic folds, redundant arytenoid mucosa) prolapse into the airway during inspiration. Supraglottoplasty/aryepiglottoplasty trims this redundant tissue to widen the supraglottic inlet.
Subglottic diameter < 4 mm in full-term infant; < 3.5 mm in preterm
| Classification | Detail |
|---|---|
| Membranous vs Cartilaginous | Membranous = soft tissue; cartilaginous = harder to treat |
| Congenital vs Acquired | Acquired = post-intubation (commonest acquired cause) |
Grading — Cotton-Myers Classification [1]:
| Grade | Obstruction |
|---|---|
| I | < 50% |
| II | 50-70% |
| III | 71-99% |
| IV | 100% (complete) |
How it's graded: During LTB, the subglottis is sized with endotracheal tubes — the largest tube with air leak at 25 cmH₂O determines the functional diameter [1].
Treatment [1]:
CO₂ laser opening, Balloon dilatation, Tracheostomy, Laryngotracheal reconstruction (LTR) with intercostal cartilage augmentation
| Type | Features |
|---|---|
| Congenital | Stridor shortly after birth, Weak cry or no cry, Choking, Idiopathic — need to rule out CNS pathology (Arnold-Chiari malformation) |
| Acquired | Post cardiac, lung, thyroid surgery |
Treatment [1]:
- Treat underlying cause
- Conservative management
- Bilateral: 50% need tracheostomy
- Congenital palsy may recover at 2-5 years old
- Definitive surgery after adolescence: lateralisation or arytenoidectomy
Why Arnold-Chiari malformation? The vagus nerve nuclei in the medulla are compressed by cerebellar tonsillar herniation → bilateral recurrent laryngeal nerve dysfunction.
Symptomatic by 3 months. Inspiratory to biphasic stridor. Recurrent croup. 50% cutaneous haemangioma.
Treatment [1]:
Systemic steroid, Oral propranolol (beta-blocker), CO₂ laser ablation in selected cases, Tracheostomy for obstructing circumferential haemangioma
Why propranolol? Beta-blockers cause vasoconstriction (blocking β₂-mediated vasodilatation), inhibit VEGF/bFGF expression, and promote apoptosis of haemangioma endothelial cells. This is now first-line medical therapy.
Stridor in neonate, respiratory distress, choking, aspiration, difficult intubation. GA for excision.
Congenital midline defect of the posterior larynx, trachea, and anterior wall of oesophagus due to incomplete formation of tracheoesophageal septum.
Benjamin-Inglis Classification [1]:
| Type | Extent of Cleft |
|---|---|
| I | Short posterior laryngeal cleft (supraglottic/interarytenoid) |
| II | Extends farther inferiorly within the laryngeal region (partial cricoid) |
| III | Extends below the larynx into the trachea, above the thoracic inlet |
| IV | Extends below the thoracic inlet — high mortality |
- Presents as stridor, aspiration on feeding
- Treatment depends on grading: conservative → endoscopic repair → open surgery
- Teratomas
60% present at birth. 75% in head & neck region. Macrocystic or microcystic. Can cause airway obstruction.
Treatment: Surgical excision; Injection with OK432 (an attenuated strain of Streptococcus pyogenes) [1]
Why OK432? It acts as a sclerosant, inducing an intense inflammatory reaction within the cyst wall, leading to fibrosis and shrinkage. Works best for macrocystic lesions.
1:8000 live births. F:M = 2:1. Failure of breakdown of buccopharyngeal membrane. Unilateral:Bilateral = 3:2. Bilateral is an ENT emergency because neonates are obligate nasal breathers. Treatment: Transnasal opening of atresia.
Exam Trap
A unilateral choanal atresia may present late (chronic unilateral nasal discharge) and is NOT an emergency. Only bilateral is immediately life-threatening because neonates cannot mouth-breathe effectively.
Pierre Robin syndrome, Treacher Collins syndrome, Apert syndrome, Crouzon syndrome — causing hypoplastic mandible, hypoplastic maxilla, retrognathia, choanal atresia
- Mandibular distraction may be used to advance the mandible and relieve airway obstruction [1]
Vascular ring (double aortic arch), Aberrant subclavian artery, Aberrant pulmonary artery — all cause extrinsic compression of trachea. Managed by CTSU (Cardiothoracic Surgical Unit).
Paediatric Acquired UAO Emergencies
6 months to 3 years, peak at 2 years. Caused by Parainfluenza virus, Influenza virus type A, RSV, Mycoplasma pneumoniae.
| Feature | Detail |
|---|---|
| Preceded by URTI | Viral prodrome |
| Hoarseness | Laryngeal involvement |
| Barking cough | Pathognomonic — seal-like |
| Biphasic stridor | Subglottic level |
| XR neck: steeple sign | Subglottic narrowing on AP view |
Management [1]:
5-10% may need admission. Systemic steroid. Nebulised adrenaline. Intubation for severe cases.
Recurrent croup needs to rule out underlying subglottic stenosis [1]
ENT & Paediatric emergency. 2-6 years old, peak 3-4 years. Caused by Haemophilus influenzae type B, β-haemolytic Streptococcus, Pneumococcus, Staphylococcus.
| Feature | Detail |
|---|---|
| Rapidly worsening sore throat | Abrupt onset (hours, not days) |
| High fever | > 38.5°C, toxic child |
| Inspiratory stridor | Supraglottic obstruction |
| Drooling | Cannot swallow secretions |
| Hot potato voice, muffled | Supraglottic swelling |
| Tripod sign | Sitting upright, leaning forward, hands on knees |
| XR neck: thumb sign | Swollen epiglottis on lateral view |
Management [1]:
Keep calm. No attempt for throat exam, blood taking or IV access [in the ward]. Diagnosis by history. Consult senior, senior paediatrician, ENT, anaesthetist. Bring patient to operation theatre. Gaseous induction followed by intubation. Blood culture, set up IV line [AFTER intubation]. Antibiotics: 3rd generation Cephalosporin.
Critical Exam Point
NEVER examine the throat of a child with suspected epiglottitis outside the operating theatre. Using a tongue depressor can provoke laryngospasm and complete airway obstruction. All invasive procedures (blood taking, IV access) should wait until the airway is secured. [1]
Croup vs. Epiglottitis — Key Discriminators:
| Feature | Croup | Epiglottitis |
|---|---|---|
| Onset | Over days | Abrupt (hours) |
| Age | 6 months–3 years | 2–6 years |
| Prodrome | URTI | None |
| Appearance | Relatively well | Toxic, very ill |
| Fever | Low (< 38.5°C) | High (> 38.5°C) |
| Drooling | No | Yes |
| Cough | Barking | Absent |
| Swallowing | Normal | Dysphagia |
| Voice | Hoarse | Hot potato, muffled |
| Stridor | Loud, harsh | Soft, whispering |
| XR sign | Steeple sign | Thumb sign |
| Treatment | Steroids + neb adrenaline | Secure airway in OT + IV 3rd gen ceph |
Commonest deep neck infection in children < 4 years. Infected retropharyngeal lymph nodes.
| Feature | Detail |
|---|---|
| Mimics croup | Hx of URTI |
| Toxic, fever | |
| Head hyperextended, stiff | Neck rigidity |
| Inspiratory stridor | |
| Dysphagia, dribbling | |
| XR neck: increased retropharyngeal space | > half vertebral body width in children |
| CT with contrast | Gold standard for diagnosis |
Management: Watch out for airway. Transoral drainage and antibiotics. [1]
HPV 6, 11. Mother infected with genital warts → transmitted during delivery. Mean age of presentation 2 years. Papillomas can occur from lips to lungs. Presents with hoarseness, stridor.
Treatment [1]:
Excision with laryngeal debrider, CO₂ laser ablation, may need repeated sessions to prevent airway obstruction
Common between 1-3 years. Ask about choking episode, coughing spells, any witness.
| Feature | Detail |
|---|---|
| Variable signs and symptoms | |
| Stridor, wheezing | Depends on location |
| Poor feeding | |
| Unilateral decreased air entry, wheezing | Classic sign |
| CXR: hypoinflation on inspiration, hyperinflation on expiration | Air trapping distal to FB |
| 25-50% can have normal CXR | Do NOT exclude on normal CXR |
Management: Rigid bronchoscopy (ventilating bronchoscope) under GA for removal [1]
Adult Upper Airway Obstruction
Tumours (nasal cavity to larynx, thyroid), Infection (parapharyngeal abscess, peritonsillar abscess, Ludwig's angina, submandibular abscess), Bilateral vocal cord palsy, Trauma, Foreign body, Anaphylaxis, OSAS
Sore throat, Dyspnoea, Dysphagia, Hoarseness, Blood in saliva, Nasal symptoms, Smoking, Drinking, Fever, Neck swelling/pain
Vital signs, Fever, Head & neck exam, Oral cavity, Thyroid, Neck lymph nodes
XR neck, CXR, Laryngoscopy, Urgent CT neck ± oral cavity or thorax with contrast
Collection of pus between tonsillar capsule and superior constrictor. Sore throat, Dysphagia, Odynophagia, Airway obstruction, Peritonsillar swelling, Deviation of uvula to the other side, Trismus.
Management: Transoral incision and drainage, antibiotics [1]
Parapharyngeal abscess, retropharyngeal abscess. Causes: tonsillitis, dental origin. Neck swelling, sore throat, odynophagia, trismus, airway obstruction, stridor.
Management: Urgent consult ENT, watch out for airway obstruction, Laryngoscopy, Urgent CT neck with contrast, Transcervical drainage ± tracheostomy, Antibiotics, Consult dental for assessment. [1]
Infection of floor of mouth, submental and submandibular space. Septic. Hot-potato voice, dysphagia. Tender swelling at submental. Superior, posterior displacement of tongue → airway obstruction. Trismus.
Management: Urgent consult ENT, Laryngoscopy, CT oral cavity and neck with contrast, Transcervical drainage ± tracheostomy [1]
Why is Ludwig's angina so dangerous? The infection spreads through the fascial planes of the floor of mouth, pushing the tongue posterosuperiorly into the airway. Unlike quinsy, the pus is diffuse (cellulitis/phlegmon), making drainage more challenging, and airway compromise is rapid.
Can occur in adults. Sore throat, rapid onset, dysphagia. PE: painful over central neck. Watch out for airway obstruction. Consult ENT → laryngoscopy ± intubation or tracheostomy. Severe cases may be done in operation theatre. IV Augmentin.
Obstruction due to CA oropharynx, tongue, larynx, hypopharynx, thyroid. Bilateral vocal cord palsy in advanced CA oesophagus, thyroid. NPC.
- Blunt or penetrating neck injury → laryngeal fracture, haematoma, oedema → airway compromise
- Requires urgent ENT assessment, may need emergency tracheostomy
Difficulty in breathing, stridor. Causes include tumours, iatrogenic cause, stroke. Consult ENT, Laryngoscopy, Emergency tracheostomy.
Why bilateral VCP causes airway obstruction: Both cords sit in the paramedian position (adducted), leaving only a narrow slit for airflow. Unilateral palsy usually causes hoarseness without significant airway compromise because one cord can still abduct. [4][5]
Tracheostomy
1. Upper airway obstruction 2. For assisted ventilation 3. Prolonged intubation 4. Bronchial toilet
These align with the anaesthesia/surgery framework [4][5]:
- Bypass UAO (intrinsic tumour/foreign body, extrinsic compression, post-op oedema)
- Prolonged mechanical ventilation (avoid complications of prolonged ETT — laryngeal injury, patient discomfort)
- Facilitate weaning from ventilation
- Suctioning of secretions (bronchial toilet)
GA or LA (if failed intubation). Dissection down to trachea. Incision between 2nd and 3rd tracheal ring. Insertion of tracheostomy tube.
Why between 2nd and 3rd ring? Too high (1st ring/cricothyroid membrane area) risks subglottic stenosis and damage to the cricoid cartilage. Too low risks injury to the innominate artery and increases the risk of tracheo-innominate fistula. The 2nd-3rd interspace is the sweet spot for access while minimising complications.
| Early | Late |
|---|---|
| Bleeding | Granuloma — skin, suprastomal |
| Misplaced tube / false tract | Stenosis — subglottis, suprastomal, stomal, cuff, tip |
| Surgical emphysema | Tracheo-innominate fistula |
| Pneumothorax | Tracheoesophageal fistula |
| Obstructed tube | Suprastomal collapse |
| Dislodged tube | Chest infection |
Tracheo-innominate Fistula
This is a life-threatening late complication. The innominate artery crosses anterior to the trachea at approximately the 9th tracheal ring, but a low tracheostomy or an excessively long tube/high cuff pressure can erode into it. Presents as massive haemorrhage from the stoma. Emergency management: overinflate the cuff, apply digital pressure through the stoma against the manubrium (Utley manoeuvre), and rush to OT. [1][5]
CXR to rule out pneumothorax. Check tube tip position — 1-2 cm above carina for infants.
1. Immediate post-op — CXR to rule out pneumothorax 2. Emergency preparation in case of early dislodgement in ward 3. Frequent suction to prevent blockage, check patency and position of tube and tapes 4. Daily dressing 5. Change of tube — first change at 5-7 days, then depending on tube type and risk of blockage 6. Assess and decide on feeding mode for the patient 7. Long-term: home care plan, types of tube, equipment (suction machine, ventilator), speaking valve 8. Short-term: ENT assessment and time for decannulation
| Feature | Options | Notes |
|---|---|---|
| Size | Paediatric (age-based chart) vs Adult (common size 7, 7.5, 8 Portex) | Match to body build |
| Material | Plastic (Portex) vs Metal (old, seldom used) | |
| Cuff | Cuffed vs Non-cuffed | Cuffed: for ventilation, aspiration prevention. Paediatric tubes: mainly non-cuffed, even for ventilation |
| Fenestration | Non-fenestrated vs Fenestrated | Fenestrated: promotes translaryngeal airflow, aids phonation, but risk of granuloma formation around fenestrated area |
| Inner tube | Long-term tubes have outer + inner tube | Inner tube can be removed for cleaning — reduces risk of blockage |
Components of a long-term tracheostomy tube [1]: outer cannula, shaft, fenestration (if present), cuff, pilot balloon, faceplate, and inner cannula.
Short-term adult tubes require regular change every week. Common adult sizes: 7, 7.5, 8 (Portex). [1]
Paediatric Tracheostomy Size Chart [1]:
| Age | Preterm–1 mo | 1–6 mo | 6–18 mo | 18 mo–3 yr | 3–6 yr | 6–9 yr | 9–12 yr | 12–14 yr |
|---|---|---|---|---|---|---|---|---|
| Tracheal transverse diameter (mm) | 5 | 5–6 | 6–7 | 7–8 | 8–9 | 9–10 | 10–13 | 13 |
| Great Ormond Street ID (mm) | 3.0 | 3.5 | 4.0 | 4.5 | 5.0 | 5.5 | 6.0 | 7.0 |
| Great Ormond Street OD (mm) | 4.5 | 5.0 | 6.0 | 6.7 | 7.5 | 8.0 | 8.7 | 10.7 |
| Shiley size | 3.0 | 3.5 | 4.0 | 4.5 | 5.0 | 5.5 | 6.0 | 6.5 |
One-way valve allows free airflow into lungs. Valve closed on exhalation → directs expired air up the larynx and out through mouth/nose for phonation. Assess duration of use as tolerated, saturation monitoring, may need ST (speech therapy) assessment and training, increase use gradually especially in children.
Prerequisite for speaking valve use: There must be some air leak around the tracheostomy tube (i.e., cuff must be deflated or tube must be uncuffed). If the cuff is inflated, expired air cannot pass upward through the larynx and the patient will suffocate.
| ETT | Tracheostomy | |
|---|---|---|
| Insertion | Easier, quicker | More invasive, surgical |
| Patient comfort | Poor (needs sedation) | Better |
| Suctioning | Harder | Easier |
| Replacement | Difficult | Easy |
| Speech/swallowing | Impaired | Enhanced (with speaking valve) |
| Dead space | Larger | Reduced |
| Complications | Vocal cord injury | Stomal complications |
Integration with Related Material
If a patient presents with UAO:
- Assess ABCDE
- Basic airway manoeuvres: Head-tilt chin-lift (if no C-spine concern), Jaw thrust (if C-spine concern)
- Airway adjuncts: OPA (unconscious only — triggers gag in conscious), NPA (semi-conscious; C/I if basal skull fracture)
- Ventilation: BVM with reservoir + high-flow O₂
- Advanced: ETT intubation (gold standard definitive airway)
- Surgical airway: Needle cricothyrotomy (emergency, last resort, ~30 min max) → Tracheostomy (definitive)
Post-thyroidectomy bilateral RLN injury → bilateral VCP → dyspnoea + stridor upon extubation → require immediate re-intubation ± tracheostomy. Post-thyroidectomy haematoma → venous obstruction → acute laryngeal oedema → airway compromise — management: cut subcuticular stitches and strap muscle stitches to evacuate haematoma. A surgical drain post-thyroidectomy serves to prevent airway obstruction by releasing pressure caused by wound swelling (as tested in 2025 MCQ Q53).
Common Exam Traps
-
Croup vs. Epiglottitis: The examiner will test whether you can differentiate. Key discriminators: barking cough (croup) vs. drooling (epiglottitis); gradual onset vs. abrupt; steeple sign vs. thumb sign. NEVER examine the throat in suspected epiglottitis.
-
Phase of stridor: Inspiratory = supraglottic/glottic. Biphasic = subglottic. If the question says "biphasic stridor in an infant with recurrent croup" → think subglottic stenosis or subglottic haemangioma, not just simple croup.
-
Normal CXR does NOT exclude foreign body — 25-50% can have normal CXR [1].
-
Tracheostomy tube first change at 5-7 days — before this, a fresh tract hasn't matured, and reinsertion through a false tract is dangerous.
-
Laryngomalacia has normal cry — if the cry is weak/absent, think vocal cord palsy.
-
Bilateral choanal atresia = emergency (neonates are obligate nasal breathers). Unilateral is NOT an emergency.
-
Speaking valve requires cuff deflated — if cuff stays inflated, expired air cannot escape upward → suffocation.
-
Subglottic stenosis grading is done at LTB — largest ETT with air leak at 25 cmH₂O, then Cotton-Myers classification.
-
Tracheostomy incision is at 2nd-3rd tracheal ring — NOT at the cricothyroid membrane (that's for emergency cricothyrotomy).
-
Retrosternal goitre causing inspiratory wheeze — tested in 2024 MCQ EMQ (wheezing during inspiration → retrosternal goitre) [9].
High Yield Summary
- Upper airway obstruction key points for exam
- Stridor phase localises the obstruction:** Inspiratory = supraglottic/glottic; Biphasic = subglottic/trachea; Expiratory = trachea/bronchi
- Laryngomalacia** = commonest cause of stridor in infants (80%), onset first 2 weeks, normal cry, self-limiting by 12-18 months, supraglottoplasty for severe cases
- Croup vs. Epiglottitis:** Gradual onset/barking cough/steeple sign vs. Abrupt/drooling/thumb sign. NEVER examine the throat in suspected epiglottitis — take child to OT for gaseous induction + intubation
- Foreign body:** 1-3 years, 25-50% have normal CXR, remove with ventilating bronchoscope
- Adult UAO causes:** Tumour, deep neck infection (Ludwig's, parapharyngeal, peritonsillar abscess), bilateral VCP, trauma, anaphylaxis
- Tracheostomy indications:** UAO, assisted ventilation, prolonged intubation, bronchial toilet
- Tracheostomy complications:** Early (bleeding, false tract, surgical emphysema, pneumothorax, tube obstruction/dislodgement) and Late (granuloma, stenosis at multiple levels, tracheo-innominate fistula, tracheoesophageal fistula)
- Post-op CXR** mandatory to exclude pneumothorax; first tube change at 5-7 days
- Tube selection:** Cuffed for ventilation; fenestrated for phonation (risk of granuloma); paediatric = mainly non-cuffed
- Speaking valve:** Requires cuff deflated; one-way valve directs expired air through larynx for phonation
Active Recall - Lecture Notes
[1] Lecture slides: GC 220. Upper airway obstruction and tracheostomy.pdf [2] Senior notes: Adrian Lui Pediatrics Notes.pdf (p.155) [3] Senior notes: MBBS Final MB (Pediatrics) (Felix PY Lai).pdf (p.137, p.144) [4] Senior notes: Maksim Surgery Notes.pdf (p.14-15, p.288-289) [5] Senior notes: MBBS Final MB (Surgery) (Felix PY Lai).pdf (p.55, p.62-63) [6] Senior notes: Ryan Ho Critical Care.pdf (p.4, p.7, p.12-13) [7] Senior notes: Ryan Ho Endocrine.pdf (p.22) [8] Senior notes: Block A - I am losing weight and sweating all the time_ causes of severe, weight loss; thyrotoxicosis; hypothyroidism.pdf (p.22) [9] Past papers: 2024 Fourth Summative MCQ.pdf (p.37, EMQ Section B Q1)
GC219 Infections And Tumours In Pharynx And Oral Cavity
Infections and tumors of the pharynx and oral cavity encompass a spectrum of inflammatory, infectious, and neoplastic conditions—including pharyngitis, tonsillar abscess, oral candidiasis, and squamous cell carcinoma—that affect the mucosal surfaces of the mouth and throat.
GC221 Vertigo Peripheral And Central
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