Bronchography - Comprehensive MD Exam Answer (10 Marks)

Definition

Contrast Media Used

• Radio-opaque (iodine-based)
• Viscid enough to coat bronchial walls
• Absorbable or removable by coughing

1. Propyliodone (Dionosil) - oil-based suspension; most commonly described in classical texts
2. Dionosil aqueous - water-miscible, less irritating
3. Barium sulfate - rarely used due to retention risk
4. Powdered tantalum - insoluble, used for radiographic contrast in some centres

Indications

Primary Indications:

1. Bronchiectasis - the classical indication; to determine extent and localization of disease before surgical resection. Most disease affects the left lower lobe and lingula.
2. Lung abscess - to delineate the cavity and draining bronchus
3. Congenital anomalies of the bronchial tree - sequestration, bronchial atresia
4. Suspected bronchial obstruction or stenosis - where bronchoscopy is not possible (e.g., lumen too narrow for bronchoscope)
5. Tracheomalacia / bronchomalacia - when endoscopic access is limited
6. Bronchobiliary fistula or bronchopleural fistula - to define the communication
7. Foreign body localization - pre-operative planning
8. Unresolved or recurrent pneumonia - to identify underlying structural abnormality
9. Preoperative evaluation before pulmonary resection
10. Selective bronchography - as an adjunct to fiberoptic bronchoscopy for segmental assessment

Contraindications

Absolute Contraindications:

1. Known iodine hypersensitivity (iodism)
2. Active haemoptysis - risk of flooding the airways
3. Severely compromised respiratory reserve (cannot tolerate even unilateral lung filling)

Relative Contraindications (K.J. Lee's Essential Otolaryngology):

1. Acute infection / active pulmonary tuberculosis
2. Acute asthmatic attack (bronchospasm risk)
3. Acute cardiac failure
4. Pregnancy (radiation and contrast exposure)
5. Recent myocardial infarction
6. Severe pulmonary hypertension

Pre-Procedure Preparation

1. Iodine sensitivity test must be performed and excluded before the procedure
2. Physiotherapy - postural drainage and percussion to clear accumulated secretions before the procedure; reduces risk of mixing contrast with pus
3. Fasting - patient kept nil-by-mouth
4. Sputum culture and sensitivity - to assess baseline infection
5. Respiratory function tests (spirometry) - baseline assessment
6. Sedation / antibiotic prophylaxis as needed
7. If children require the procedure - general anaesthesia, and only one lung at a time should be studied

Technique

Anaesthesia:

• Preferred: Local anaesthesia - so the patient can cough vigorously and help distribute contrast and clear it post-procedure
• General anaesthesia - used in children; only one lung per session

Steps:

1. Topical anaesthesia of the larynx, trachea, and bronchi using 4% lignocaine (lidocaine) spray
2. Patient positioned appropriately (supine, then tilted to fill dependent bronchi)
3. Catheter introduction - a gum elastic catheter (Metras catheter) or cricothyroid injection needle is passed:
   • Via translaryngeal (transglottic) route - catheter passed through the glottis
   • Via cricothyroid puncture - needle introduced through cricothyroid membrane directly into trachea
   • Via fiberoptic bronchoscope - for selective bronchography (most modern approach)
   • Via nasotracheal route - in children
4. Contrast injection: 10-20 mL of contrast introduced slowly under fluoroscopic guidance; patient is tilted in different positions (Trendelenburg, lateral decubitus) to fill specific bronchopulmonary segments
5. Radiographs taken immediately in AP, lateral, and oblique projections
6. Patient encouraged to cough forcibly to clear contrast
7. Physiotherapy post-procedure to assist clearance

Findings on Bronchogram

• Trachea, main bronchi, lobar, segmental, and sub-segmental bronchi
• Normal branching pattern ("tree in leaf" appearance)

Pathological findings:

Complications

1. Bronchospasm / laryngospasm - due to contrast irritation
2. Exacerbation of pulmonary infection - chemical irritation precipitates acute flare
3. Aspiration pneumonitis - if contrast floods alveoli
4. Iodine hypersensitivity reaction - mild (urticaria) to severe (anaphylaxis)
5. Respiratory failure - if bilateral filling done simultaneously in compromised patient
6. Vagal reaction / vasovagal syncope - during catheter manipulation
7. Haemoptysis - mucosal trauma from catheter
8. Retention of oily contrast - granuloma formation (with oil-based agents)

Current Status / What Has Replaced It

Summary Table for Quick Recall

• Pye's Surgical Handicraft, 22nd Edition - Bronchography section
• Murray & Nadel's Textbook of Respiratory Medicine - Chapter on Imaging
• K.J. Lee's Essential Otolaryngology - Contraindications and ENT perspective
• Scott-Brown's Otorhinolaryngology Head & Neck Surgery - Tracheal stenosis evaluation