01Approach to the Critical Patient/attcp52

Immediate airway priorities

›Critical airway recognition

›Stridor at rest indicates luminal narrowing greater than 50%

›Critical stenosis typically at greater than 70% obstruction

›Immediate intervention threshold

›Inability to speak in full sentences

›Impending respiratory failure

›Escalate immediately

›Cyanosis or SpO2 below 90%

›Pre-oxygenate before any intervention

›Avoid sedation without airway secured

›Airway management decision

›If patent airway and partial stenosis, optimize positioning upright

›Heliox 70:30 mixture reduces turbulent flow resistance

›Reduces work of breathing acutely

›If critical obstruction, awake fiberoptic intubation preferred

›RSI risks complete obstruction with paralysis

›Smallest ETT that passes the stenosis

›Surgical airway if intubation fails below level of stenosis

›Emergency tracheostomy or cricothyrotomy

›ENT or thoracic surgery stat

›Rigid bronchoscopy preferred for definitive acute decompression

›Can dilate acutely in OR setting

›Interventional pulmonology or thoracic surgery activation

Hemodynamic monitoring and targets

›Monitoring bundle

›Continuous pulse oximetry

›SpO2 target 94 to 98%

02History/hx80

Symptom characterization

›Core airway symptoms

›Dyspnea on exertion (most common presenting symptom)

›Progressive exertional limitation

›Inability to perform ADLs

›Stridor character

›Inspiratory = extrathoracic (supraglottic, subglottic)

›Biphasic = fixed intrathoracic or subglottic

›Expiratory = intrathoracic

›Chronic cough

›Non-productive

›Effort-related worsening

›Hoarseness or voice change

›Subglottic or vocal cord involvement

›Onset and progression

›Post-intubation stenosis

›Typically 4 to 6 weeks after extubation

›Delayed dyspnea onset

›Insidious onset in inflammatory causes

›Median diagnostic delay 12 months

›Frequently misdiagnosed as asthma or COPD

›Acute onset suggests malignancy or foreign body

›Alarm features

›Stridor at rest

›Greater than 50% luminal narrowing

›Emergent evaluation required

›Hemoptysis

›Malignant etiology concern

03Physical Exam/exam59

Vital signs and general appearance

›Stability markers

›Respiratory rate

›Greater than 30 per minute as severity threshold

›Accessory muscle use

›Oxygen saturation

›Room air baseline critical

›Hypoxia is a late finding

›Blood pressure and heart rate

›Tachycardia from respiratory distress

›Hypertension from air hunger

›Work of breathing signs

›Suprasternal and intercostal retractions

›Inspiratory effort against fixed obstruction

›Tracheal tug

›Severe obstruction sign

›Tripod positioning

›Near-critical obstruction

›Inability to speak in full sentences

Airway and chest exam

›Auscultation findings

›Monophonic stridor loudest over neck and central airways

›Distinguishes from diffuse polyphonic asthma wheeze

›Fixed upper airway obstruction pattern

›Diminished air entry in severe stenosis

›Bilateral quiet chest is pre-arrest

›Biphasic stridor at rest

›Fixed stenosis pattern

04Differential Diagnosis/ddx42

Life-threatening diagnoses

›Critical airway emergencies

›Malignant tracheal obstruction

›ICD-10 C33 (tracheal malignancy)

›Rapid progression, hemoptysis, constitutional symptoms

›Angioedema

›Acute onset, urticaria, ACE inhibitor use

›Epinephrine response distinguishes

›Epiglottitis

›Acute febrile illness, drooling, muffled voice

›Laryngoscopy confirms

›Foreign body aspiration

›Acute onset, choking episode

›Focal monophonic wheeze

Common mimics

›Obstructive lung disease mimics

›Asthma or reactive airway disease

›ICD-10 J45

›Most common misdiagnosis of tracheal stenosis

›Distinguishing: lack of bronchodilator response, fixed obstruction on PFTs

›COPD

›ICD-10 J44

›Diffuse lower airway obstruction

›Coexisting COPD may mask tracheal stenosis on PFTs

›Vocal cord dysfunction

›Episodic inspiratory stridor

›Normal between episodes

›Provocation testing and laryngoscopy

05Laboratory Tests/lt46

Baseline and preoperative labs

›Routine baseline

›Complete blood count

›Leukocytosis in infectious etiology

›Eosinophilia in eosinophilic granulomatosis

›Comprehensive metabolic panel

›Renal function for contrast clearance

›Hepatic function for drug metabolism

›Coagulation studies (INR, aPTT)

›Preoperative bronchoscopy preparation

›Anticoagulation reversal planning

Autoimmune and inflammatory workup

›Vasculitis panel

›ANCA (anti-neutrophil cytoplasmic antibodies)

›c-ANCA/PR3 for GPA (sensitivity 85 to 90% in active disease)

›p-ANCA/MPO for microscopic polyangiitis

›ESR and CRP

›Inflammatory activity markers

›Monitoring treatment response

›ANA and anti-dsDNA

›Lupus evaluation if suspected

›Complement levels (C3, C4)

›Consumption in active vasculitis

›Rheumatologic additional markers

›Anti-CCP and rheumatoid factor

›Rheumatoid arthritis-related airway involvement

›Serum ACE

›Sarcoidosis evaluation

06Diagnostic Tests/dt83

Scoring Systems

›Cotton-Myer grading system (subglottic stenosis)

›Grade I: 0 to 50% obstruction

›Often asymptomatic at rest

›Symptoms with exercise

›Grade II: 51 to 70% obstruction

›Exertional dyspnea

›Stridor with exertion

›Grade III: 71 to 99% obstruction

›Stridor at rest

›Critical stenosis threshold

›Grade IV: 100% obstruction (complete)

›No lumen

›Requires surgical airway

›McCaffrey classification (laryngotracheal stenosis)

›Stage I: subglottic or tracheal only, less than 1 cm

›Stage II: subglottic only, greater than 1 cm

›Stage III: subglottic and tracheal without glottic involvement

›Stage IV: any involvement of glottis

›Higher stage correlates with worse surgical outcomes

›Myer-Cotton grading guides surgical planning

›Grade I to II: endoscopic dilation often sufficient

›Grade III to IV: laryngotracheoplasty or resection usually required

MRI

›MRI indications for tracheal stenosis

›Soft tissue characterization

›Better tissue contrast than CT for inflammatory vs fibrotic disease

›Cartilage involvement assessment in relapsing polychondritis

›GPA-associated subglottic stenosis grading

›MRI accuracy correlates well with PFTs and laryngoscopy

›Useful when radiation minimization desired (younger patients)

›MRI technique

›T1 and T2 sequences through larynx and trachea

›Active inflammation: T2 hyperintense

›Fibrosis: T1 and T2 hypointense

›Gadolinium enhancement

›Active granulomatous disease enhances

›Contraindicated in renal impairment (GFR below 30)

›MRI limitations

›Motion artifact from respiration

›Respiratory gating required

›Limited availability in acute settings

›Cannot be used in patients with ferromagnetic implants

CT

›CT indications

›First-line imaging for suspected tracheal stenosis

›ACR Appropriateness Criteria: CT is initial modality of choice (Usually Appropriate)

›CT with IV contrast preferred when malignancy or mediastinal pathology suspected

›Length, location, and degree of stenosis quantification

›Coronal and sagittal multiplanar reformats essential

›Virtual bronchoscopy reconstruction possible

›CT findings

›Intraluminal narrowing measurement

›Compare to adjacent normal tracheal caliber

›Normal adult tracheal diameter: 13 to 25 mm transverse

›Airway wall thickening pattern

›Circumferential in post-intubation and GPA

›Posterior sparing in relapsing polychondritis

›Extraluminal causes

›Mediastinal mass, thyroid goiter, vascular ring

›Dynamic expiratory CT

›Tracheobronchomalacia diagnosis

›Expiratory collapse greater than 50% diagnostic

›Complements static CT when dynamic obstruction suspected

›CT protocol

›Helical acquisition from thoracic inlet to carina minimum

›Slice thickness 1 mm or less for reformats

›Inspiratory and expiratory phases if dynamic collapse suspected

Ultrasound

›Ultrasound role in tracheal stenosis

›Point-of-care assessment

›Tracheal diameter estimation possible at neck

›Less accurate than CT for stenosis grading

›Guidance for percutaneous tracheostomy

›Tracheal ring identification

›Vessel avoidance (anterior jugular veins)

›Endobronchial ultrasound (EBUS)

›Mediastinal lymphadenopathy assessment

›Malignant or sarcoid involvement of nodes

›Transbronchial needle aspiration (TBNA) guidance

›Tissue diagnosis for extrinsic compression

›Neck ultrasound

›Thyroid goiter quantification

›Tracheal deviation degree

›Vascular mapping before surgery

›Limited by tracheal air column artifact

›Posterior tracheal wall not assessable

07Disposition/dispo32

Admission indications

›ICU-level admission criteria

›Stridor at rest or impending airway compromise

›Requires continuous monitoring

›Immediate bronchoscopy availability

›SpO2 below 92% on supplemental oxygen

›Escalating oxygen requirement

›Post-procedural airway edema risk

›Following dilation in high-grade stenosis

›New or planned tracheostomy

›Immediate post-procedure care

Ward or monitored bed admission

›Intermediate care criteria

›Moderate symptomatic stenosis requiring scheduled bronchoscopy

›Stable on supplemental oxygen

›No stridor at rest

›Newly diagnosed autoimmune tracheal stenosis

›Immunosuppression initiation

›Monitoring for steroid complications

›Post-dilation without complications

›4 to 6 hour observation minimum

›Discharge when tolerating oral intake and SpO2 stable

Discharge criteria

›Safe discharge requirements

›SpO2 greater than 93% on room air or baseline home oxygen

›Stridor absent at rest

›Tolerating secretions and oral intake

›Clear follow-up plan

08Treatment/t93

Acute stabilization and oxygen delivery

›Initial oxygen and positioning

›High-flow supplemental oxygen

›Target SpO2 94 to 98%

›Avoid hyperoxia if COPD component

›Upright positioning (head of bed 30 to 45 degrees)

›Reduces obstruction from tracheal compression and secretions

›Heliox 70:30 (helium:oxygen)

›Reduces turbulent flow through stenotic segment

›Bridge therapy while arranging definitive intervention

›Contraindicated if FiO2 requirement above 0.3 (limits helium concentration)

›Inhaled medications (adjunctive)

›Nebulized racemic epinephrine 2.25% solution

›0.5 mL in 2.5 mL normal saline nebulized

›Mucosal edema reduction (short-term)

›Reassess within 3 to 4 hours (rebound edema)

›Inhaled budesonide

›Post-procedural recurrence prophylaxis

›Long-term use in inflammatory stenosis

Endoscopic interventions

›Rigid bronchoscopy and dilation

›Primary endoscopic intervention for benign stenosis

›Mechanical dilation with bougies or balloon

›Immediate symptom improvement

›Balloon bronchoplasty

›Radial dilation force reduces mucosal tearing compared to bougie

›Balloon diameter titrated to adjacent normal tracheal diameter

›Recurrence is common

›Greater than 85% of idiopathic SGS patients require repeat within 5 years

›76% relapse rate in inflammatory causes

›Adjunctive endoscopic therapies

›Intralesional triamcinolone acetonide injection

›40 mg per mL, inject at time of dilation

›Reduces recurrence: 37% vs 54.5% without injection

›4-quadrant injection at stenosis margins

›Topical mitomycin C application

›0.4 mg per mL concentration applied with pledget for 3 to 5 minutes

›75% success rate at 4 months vs 15% for dilation alone

›Antifibrotic action on submucosal fibroblasts

›Spray cryotherapy

›Endoluminal liquid nitrogen spray

›Disrupts fibrotic scar tissue

›Emerging evidence for benign stenosis

›Laser therapy (CO2 or Nd:YAG)

›Reserved for scar resection, not primary treatment

›Avoid with FiO2 above 0.4 (airway fire risk)

›KTP or diode laser preferred for airway use

›Airway stenting

›Indications

›Malignant obstruction, inoperable cases, complex post-surgical stenosis

›Bridge to surgery in selected cases

›Silicone stents

›Removable, preferred for benign disease

›Dumon stent most widely used

›Self-expanding metal stents (SEMS)

›Permanent, difficult to remove

›Reserved for malignant or end-stage disease

›Complications of stenting

›Granulation tissue formation (most common)

›Stent migration, mucus plugging, infection

Surgical management

›Tracheal resection and primary anastomosis

›Gold standard for definitive management of benign stenosis

›Long-term success rate 90 to 95%

›Low recurrence when performed at high-volume centers

›Indications

›Stenosis length up to 4 to 6 cm (approximately 6 tracheal rings)

›Failed endoscopic management

›Grade III to IV stenosis in good surgical candidates

›Contraindications

›Poor cardiopulmonary reserve

›Extensive stenosis length beyond resectable limits

›Active systemic infection

›Laryngotracheoplasty

›Subglottic and laryngotracheal stenosis involving glottis

›Costal cartilage grafting to widen lumen

›Staged procedures may be required

›Staged laryngotracheoplasty

›Stent placement followed by decannulation

›Predictors of decannulation: unilateral vocal cord paralysis, grade of stenosis

Pharmacologic management

›Autoimmune and inflammatory stenosis

›GPA (granulomatosis with polyangiitis)

›Systemic glucocorticoids: prednisone 1 mg per kg per day initially

›Taper over 3 to 6 months based on disease activity

›Rituximab 375 mg per m2 IV weekly for 4 doses (induction)

›Preferred over cyclophosphamide in subglottic GPA

›Methotrexate 15 to 25 mg per week as steroid-sparing maintenance

›Relapsing polychondritis

›Prednisone 0.5 to 1 mg per kg per day

›Dapsone 50 to 100 mg per day for mild disease

›Biologics (infliximab, abatacept) for refractory cases

›GERD treatment for idiopathic stenosis

›Omeprazole 80 mg per day (high-dose PPI)

›Reduces acid reflux contributing to mucosal inflammation

›Concurrent anti-reflux dietary modifications

›H2 blockers as adjunct if PPI alone insufficient

09Special Populations/sp77

Pregnancy

›Physiologic considerations

›Increased minute ventilation in pregnancy

›Dyspnea may be attributed to pregnancy

›Tracheal stenosis diagnosis may be delayed

›Reduced functional residual capacity

›Faster desaturation during apnea

›Increased urgency for airway management

›Supine aortocaval compression

›Left lateral decubitus positioning required

›Management modifications

›Bronchoscopy technically feasible in all trimesters

›Second trimester preferred for elective intervention

›Fetal monitoring during and after procedure

›Heliox safe in pregnancy

›Useful bridge to definitive intervention

›Anesthetic considerations

›Awake fiberoptic intubation strongly preferred

›Increased aspiration risk with RSI

›Drug safety

›Mitomycin C: avoid in pregnancy (teratogenic potential)

›Systemic steroids: generally safe, monitor for gestational diabetes

›Rituximab: contraindicated in pregnancy

›Methotrexate: absolutely contraindicated (Category X)

›Tracheal resection

›Deferred until postpartum when possible

›Cesarean section may be planned before elective repair

Geriatric

›Physiologic considerations

›Reduced respiratory reserve

›Less tolerance for partial obstruction

›Symptoms may develop at lower obstruction grades

›Comorbidity burden

›Cardiac disease limits surgical candidacy

›Reduced mucociliary clearance increases secretion burden

›Polypharmacy

›ACE inhibitor cough may be confounding

›Anticoagulation increases procedural risk

›Management modifications

›Endoscopic dilation preferred over surgery

›Higher surgical risk in elderly

›Repeated dilations accepted over definitive resection

›Stent use more acceptable

›Long-term stent complications outweigh in limited life expectancy

›Steroid dosing

›Increased risk of osteoporosis, diabetes, infection

›Calcium 1000 to 1200 mg per day and vitamin D supplementation

›Bone density monitoring with long-term use

›Post-procedure care

›Extended observation after bronchoscopy

›Fall risk assessment post-sedation

Pediatrics

›Unique considerations

›Congenital tracheal stenosis

›Complete cartilaginous rings (absent posterior membrane)

›Usually diffuse and affects distal two-thirds of trachea

›Associated cardiac anomalies in 50% (pulmonary artery sling most common)

›Acquired causes in pediatrics

›Post-intubation (NICU, PICU)

›Subglottic hemangioma (presents at 1 to 6 months of age)

›Croup scar

›Classic triad of congenital tracheal stenosis

›Inverted steeple sign on plain film

›Tracheal tug

›Biphasic stridor

›Weight-based and age-specific management

›Balloon dilation

›Balloon diameter selected to match adjacent normal tracheal diameter

›Smaller balloons (4 to 8 mm) in neonates and infants

›Slide tracheoplasty (surgical repair of congenital stenosis)

›Preferred surgical technique for long-segment congenital stenosis

›Divides trachea and anastomoses in offset fashion to widen lumen

›Better outcomes than resection for diffuse congenital disease

›Subglottic hemangioma

›Propranolol 2 to 3 mg per kg per day (first-line)

›Intralesional steroid injection as adjunct

›Pediatric intubation precautions

›Uncuffed tubes in children under 8 years

›Cuffed tubes at low pressure (below 20 cmH2O) if required

›High-pressure cuffs are primary iatrogenic injury mechanism

10Background/b87

Epidemiology

›Prevalence and incidence

›Post-intubation tracheal stenosis

›Incidence 10 to 22 per million people per year

›Clinically significant stenosis in 1 to 2% of intubated patients

›Severe stenosis requiring intervention in 0.1 to 0.2% of intubated patients

›Most common cause of acquired benign tracheal stenosis

›Greater than 80% of cases are iatrogenic

›Idiopathic subglottic stenosis

›Almost exclusively middle-aged white females

›Mean age 45 to 55 years

›Inflammatory causes

›GPA accounts for 41% of inflammatory stenosis

›Relapsing polychondritis accounts for 26%

›Diagnostic delay

›Median diagnostic delay of 12 months in inflammatory cases

›Frequent misdiagnosis as asthma or COPD

›Flow-volume loop often not ordered initially

›Up to 30% of patients labelled as asthma or COPD have upper airway obstruction on flow-volume loop

›Natural history

›Benign post-intubation stenosis

›Progressive without intervention

›May stabilize after initial scar maturation (3 to 6 months)

›Inflammatory stenosis

›High recurrence rate: 76% with GPA and relapsing polychondritis

›Requires ongoing endoscopic surveillance

›Idiopathic SGS

›Greater than 85% require repeat intervention within 5 years

›Gradual progression over years

Pathophysiology

›Mechanisms of stenosis formation

›Ischemic mucosal injury (primary mechanism in post-intubation)

›Tracheal mucosal blood flow ceases at 30 mmHg transmural pressure

›Cuff-to-trachea ratio greater than 150% predictive of ischemia

›Progression: ischemia, ulceration, perichondritis, granulation, fibrosis, contracture

›Granulation tissue formation

›Excessive myofibroblast activation

›TGF-beta signaling central to fibrotic process

›Tracheostomy-specific injuries

›Stoma granulation tissue

›Tracheomalacia adjacent to stoma

›High incision injures cricoid cartilage

›Inflammatory stenosis mechanisms

›GPA (granulomatosis with polyangiitis)

›ANCA-mediated neutrophil activation

›Granulomatous inflammation of submucosal tissue

›Fibrotic scarring after repeated inflammatory episodes

›Relapsing polychondritis

›Autoimmune destruction of cartilaginous matrix

›Loss of structural support leads to collapse and fibrosis

›GERD contribution

›Acid and pepsin cause direct mucosal injury

›Chronic inflammation promotes fibroblast activation

›Flow dynamics

›Turbulent flow begins when Reynolds number exceeds 2000

›Stenosis creates high-velocity jet, increasing resistance non-linearly

›Work of breathing increases exponentially with decreasing lumen diameter

›Stridor onset at greater than 50% luminal narrowing

›Critical stenosis at greater than 70% obstruction

›Any additional edema (infection, allergy) can be life-threatening

Therapeutic Considerations

›Evidence base for endoscopic treatments

›Intralesional triamcinolone reduces recurrence

›Reduces recurrence from 54.5% to 37% vs dilation alone

›Class IIa recommendation from expert consensus

›Mitomycin C adjunctive therapy

›75% success rate at 4 months vs 15% for dilation alone

›Antimitotic agent reduces submucosal fibroblast proliferation

›CHEST guideline: conditional recommendation for adjunctive use

›Spray cryotherapy emerging evidence

›Disrupts fibrotic matrix without heat-related scarring

›Promising for refractory cases

›Surgical outcomes

›Tracheal resection and anastomosis

›90 to 95% long-term success rate

›Less than 5% anastomotic complications at high-volume centers

›Predictors of need for resection vs endoscopic management

›Smoking history, length of stenosis, prior failed dilations

›Cotton-Myer Grade III to IV with failed endoscopy

›Multidisciplinary team approach

›Interventional pulmonology for endoscopic management

›Thoracic surgery for resection planning

›ENT/otolaryngology for subglottic involvement

›Rheumatology for inflammatory causes

›Speech-language pathology for voice and swallowing rehabilitation

›Surveillance strategy

›PFTs with flow-volume loop every 3 to 6 months post-treatment

›PEF decline predicts recurrence

›Bronchoscopy at 4 to 6 weeks after dilation

›Earlier if symptoms recur

11Patient Discharge Instructions/pdi39

copy discharge instructions

›Diagnosis and condition explanation

›Tracheal stenosis means narrowing of the windpipe (trachea)

›This can make breathing feel difficult, especially with exertion

›The narrowing may be caused by prior breathing tube use, autoimmune disease, or scarring

›Your treatment today may have included a breathing tube procedure, medications, or a plan for follow-up surgery

›Medications to take at home

›Take all prescribed medications as directed

›If prescribed steroids, do not stop suddenly without doctor advice

›If prescribed acid-reducing medication (PPI), take before meals

›Continue any home inhalers as prescribed

›Inhalers do not treat tracheal stenosis but help with any lung disease

›Activity instructions

›Avoid strenuous exercise until cleared by your specialist

›Moderate exertion may worsen breathlessness before your follow-up

›Sleep with head of bed elevated if breathing is more comfortable upright

›Pillows behind head and shoulders

›Avoid cigarette smoke (active or passive)

›Smoking worsens scarring and predicts need for surgery

›Diet and lifestyle

›Anti-reflux diet if heartburn is a concern

›Avoid large meals before bedtime

›Avoid spicy, acidic foods, caffeine, alcohol

›Weight reduction if overweight

›Adequate hydration to maintain airway secretion clearance

›Return to emergency department immediately for

›New or worsening noisy breathing (stridor) at rest

›This may indicate worsening narrowing

12References/r60

Guidelines and key sources

›CHEST Central Airway Obstruction Guideline 2025

›Mahmood K, Frazer-Green L, Gonzalez AV, et al.

›Management of Central Airway Obstruction: An American College of Chest Physicians Clinical Practice Guideline

›Chest. 2025

›Conditional recommendation for mitomycin C and steroid injection as adjunctive therapy

›ACR Appropriateness Criteria 2024

›Expert Panel on Thoracic Imaging, Little BP, Walker CM, et al.

›ACR Appropriateness Criteria: Tracheobronchial Disease

›Journal of the American College of Radiology. 2024

›CT chest rated Usually Appropriate as initial imaging

›ERS/ATS Technical Standard on Lung Function 2022

›Stanojevic S, Kaminsky DA, Miller MR, et al.

›ERS/ATS Technical Standard on Interpretive Strategies for Routine Lung Function Tests

›European Respiratory Journal. 2022

›Flow-volume loop interpretation for upper airway obstruction

Key clinical studies

›Risk factors for tracheal stenosis (systematic review and meta-analysis)

›Hong S, Wu X, Feng H, et al.

›Risk Factors for Patients With Tracheal Stenosis: A Systematic Review and Meta-Analysis

›Journal of International Medical Research. 2024

›Diabetes, cuff-to-trachea ratio, intubation duration as modifiable risk factors

›Inflammatory subglottic and tracheal stenosis

›Catano J, Uzunhan Y, Paule R, et al.

›Presentation, Diagnosis, and Management of Subglottic and Tracheal Stenosis During Systemic Inflammatory Diseases

›Chest. 2022

›GPA 41%, relapsing polychondritis 26% of inflammatory cases

›Endoscopic treatment of benign tracheal stenosis

Evidence & Review