This document discusses the anatomy and bronchoscopic examination of the tracheobronchial tree. It begins with the surgical anatomy of the trachea, including its length, cartilage rings, and blood supply. It then describes the branching pattern and segments of the main bronchi and lungs. Different types of bronchoscopy are explained, including rigid, flexible, and interventional bronchoscopy. Various bronchoscopic procedures are outlined such as foreign body removal, biopsy, washing, and endobronchial ultrasound-guided sampling of lymph nodes. Embryological development of the tracheobronchial tree and lungs is also summarized.

1. Tracheobronchial Tree
Anatomy and Bronchoscopy
Dr. K. Srikanth
DNB (Cardiothoracic Surgery) Resident – 2nd year
NH, Bangalore
12.09.2018

2. Surgical anatomy of trachea
• 10 – 11 cm long
• Begins at C6 below cricoid cartilage, terminates at
carina (lower border of T4)
• Anterolaterally has 16-20 incomplete hyaline
cartilaginous rings
• Posteriorly trachealis muscle (to permit peristalsis
of esophagus)

3. • Luminal diameter around 1-1.5cm
• On bronchoscopy, we can appreciate the sharp
carina
• Arterial supply – Inferior thyroid artery
branches and ascending branches of bronchial
arteries (implications on tracheal Tx)
• Venous drainage – inferior thyroid venous
plexus
• Lymphatic drainage – Pretracheal and
paratracheal nodes

5. Main Bronchi
• Right main bronchus – 1.5cm long from
bifurcation to the point of RUL
bronchus division
• RMB – Wider and more vertical than
LMB (clinical significance)
• LMB – Narrower and 4-6 cm long from
bifurcation to LUL bronchus division

7. Bronchopulmonary segments
• Anatomic and functional subdivision of lung aerated by a single
tertiary bronchus and supplied by a single segmental pulmonary
artery
• Pyramidal shape, Apex towards hilum, base towards costal surface
• Segmental vein runs in connective tissue between adjacent
bronchopulmonary segments
• Can be surgically resected - segmentectomy

10. Generations of airways

11. Bronchoscopy
(endoscopic visualisation of the
tracheobronchial tree)

12. Types
Based on utility
Diagnostic
Therapeutic (Interventional)
Based on type of scope
Rigid bronchoscopy
Flexible bronchoscopy

13. Rigid Bronchoscopy
Indications
Management of obstructing airway lesions
Retrieval of foreign bodies
Suctioning of inspissated secretions
Visualisation of bleeding/ friable lesions
Obtaining tissue biopsy specimens of endobronchial lesions deeper
and more generous than those provided by the flexible bronchoscope

14. • Internal diameter of 6-8mm, length of scope 40 cm
• Always done under GA
• Has a side port for ventilation during procedure
• Disadvantages - Needs general anaesthesia, Peripheral biopsy of
upper lobe very difficult
• Complications - injury to the gums and tooth dislodgement,
hypoventilation, airway bleeding, and direct injury to the larynx or
rupture of the tracheobronchial tree

15. Rigid bronchoscopy demo

16. Flexible bronchoscopy
• More commonly used nowadays compared to rigid scopy
Indications
Diagnosis of airway lesions
Airway trauma
Pre-op evaluation of trachea-bronchial tree
Interventions – EBUS-TBNA, Bronchial brushing, BAL collection,
bronchoscopic biopsy, etc.,

17. • Outer diameter – 6.2 mm (adult scope), 2.7mm (paediatric scope)
• Can be done awake / under IV sedation/ oropharyngeal anaesthetic
spray / intra-tracheal topical anaesthesia/ GA
• Monitoring of vitals during procedure is mandatory (vasovagal
response)
• Sterilisation of scopes is important (cidex - 2% glutaraldehyde) for
atleast 6-8 hours
• Interventional bronchoscopy – utilises flexible scopy mostly

18. Tip of the scope

19. Flexible bronchoscopy demo

20. Tracheobronchial anatomy from the inside

21. To be continued...

22. Embryology of Tracheobronchial
Tree & Lungs
Dr. K. Srikanth
DNB (Cardiothoracic Surgery) Resident – 2nd year
NH, Bangalore
17.09.2018

23. Development of proximal airways
• The development of the respiratory system begins at 4 weeks of
gestation with the development of an endodermal bud growing into
the splanchnic mesenchyme.
• The endodermal components become the epithelium and glands,
whereas the mesenchyme becomes cartilage, connective tissue, and
muscular components.
• The primordial lung appears and bulges anteriorly from the primitive
foregut. Separation of the trachea from the esophagus occurs by the
sixth week.

25. Development of lung
 5 stages of Thurlbeck:
• Embryonic stage (3-8 weeks)
• Pseudoglandular stage (9-16 weeks)
• Canalicular stage (17-28 weeks)
• Saccular stage (28 weeks – birth)
• Alveolar stage (Late fetal period – childhood)

27. Development of lung animation

28. Bronchoscopic procedures

29. Contents
• Foreign body removal
• Bronchial brushing
• Bronchoscopic biopsy
• Bronchial wash/ BAL
• Bronchial balloon dilatation +- stenting
• EBUS/ TBNA
• Autofluorescence bronchoscopy
• Photodynamic therapy

30. Foreign body removal
• Rigid bronchoscopy is preferred over flexible scope
• Caution – Risk of pushing the FB distally and causing impaction, risk of
bleeding due to manipulation
• Use of graspers, snares, graspers, tri-pronged forceps for FB retrieval
• Right bronchial FB commoner than left bronchial FB

32. FB removal demo

33. Bronchial brushing
• Cytological study (similar to a pap smear)
• For suspicious mucosal lesion (erythema/ ulceration/ leukoplakic
lesions)
• Demo

34. Bronchoscopic biopsy
• For submucosal endobronchial lesions, biopsy can be done under direct
vision
• Using flexible scope, biopsy forceps is advanced and a piece of tissue with
surrounding normal tissue is grasped and biopsied
• Management of bleeding after biopsy is important – cautery, balloon
tamponade, 1:100,000 adrenaline soaked gauze, Nd-YAG laser
photoablation, cryo-ablation
• Electromagnetic navigation guided biopsy can be done for peripheral
tumours

35. Bronchial wash/ BAL
• BAL is to done to recover material from terminal bronchiole / alveolar sacs
• Flexible scope is preferably used
• Scope is wedged into a segmental bronchus and 100-200ml saline is
instilled into the wedged segment (BAL), lesser quantity (30-50ml) for wash
• Suction is applied and fluid is evacuated which is trapped in a trap bottle
and sent for microbiological/ pathological evaluation

36. Bronchoscopic balloon dilatation/ stenting
• For short segment tracheal stenosis/ palliation of endo-luminal
tumours, this is a good option
• Using flexible scope, a balloon dilator is passed down to the stenosed
segment, balloon is dilated and kept dilated for atleast 2 minutes
• Post-dilatation, a stent(bare metal/ covered) is deployed to prevent
re-stenosis
• Demo

37. EBUS / TBNA
• CT scan is mandatory prior to TBNA for gauging the distance of the
lymph node from fixed landmarks like carina
• Wang’s lymph nodal map – 11 nodal stations accessible for TBNA
• TBNA not recommended for para-aortic/para-PA nodes
• Simple jabbing technique/ “hub against the wall” technique

38. Wang’s lymph node map

39. • Demo
• Management of bleeding is crucial as explained previously

40. Role of intervention in massive hemoptysis
• Rigid bronchoscope is preferred as it helps to clear out the bledding quickly
and also helps to maintain ventilation simultaneously
• Once bleeder is identified, options are
Adrenaline-soaked pledget
Fogarty balloon tamponade
Electrocautery
Cryo-ablation
Silicone endobronchial stents
Bronchial artery embolization

41. Laser bronchoscopy
• Lasers produce a beam of monochromatic, coherent light that can
induce tissue vaporization, coagulation, hemostasis and necrosis
• Bronchoscopic laser therapy is also beneficial in the treatment of
tracheobronchial disorders including endoluminal endobronchial
lesions, inflammatory strictures, obstructive granulation tissue,
amyloidosis, and benign tumors such as hamartomas.
• Initially, CO2 laser was used because of good cutting property but has
low penetration (0.1-0.5mm) and poor hemostatic property

42. • Presently, Nd-YAG laser (Neodymium – Yttrium, Aluminium, Garnett)
is preferred
• Penetration of about 3-5mm and good hemostatic property, less
efficient for cutting compared to CO2 laser
• Complications may arise and include cardiac arrhythmias, airway
perforation, pneumothorax, hemorrhage, hypoxemia, or
endobronchial fire (ignition of the bronchoscope or endotracheal
tube)
• Risk of fistula formation if used close to adjacent structures

43. Autofluorescence bronchoscopy
• Photosensitizers, such as hematoporphyrin derivative (HPD) and-
aminolevulinic acid (-ALA), are retained more selectively by neoplastic
tissues.
• When stimulated by blue light (wavelength approximately 440 nm),
tissues containing these photosensitizers (i.e., tumors, but not normal
tissues) emit weak fluorescence in the red spectrum (wavelength
approximately 630 nm).
• The low-intensity fluorescence can be captured by specially designed
image intensifiers. The technique may be helpful in cancer detection
or in the delineation of tumor limits.

45. Bronchoscopic brachytherapy
• Endobronchial brachytherapy involves the bronchoscopic insertion of
a thin, hollow catheter through a malignant obstruction under
fluoroscopic guidance.
• A radioactive implant is then inserted into the catheter and left in
position for a predetermined period (2 to 40 hours, depending on the
dose rate).

46. Photodynamic therapy (PDT)
• Tumor necrosis occurs as a result of cellular destruction through the
generation of oxygen-free radicals or by ischemic necrosis mediated
by vascular occlusion resulting from thromboxane A2 release.
• The selective effect of PDT on malignant cells is thought to be due to
the differential uptake and retention of photosensitizing agents in
neoplastic cells rather than in normal cells.
• This selectivity effect appears to be most pronounced approximately
24 to 48 hours after infusion of the photosensitizing agent
(Porphymer sodium). For this reason, bronchoscopic treatment of
target lesions is often performed 1 to 2 days after the agent
(hematoporphyrin derivatives) has been injected.

47. Take home messages
• To understand the basic anatomy & development of the
tracheobronchial tree
• Bronchoscopy – not just a physician’s niche
• To understand appropriate usage of bronchoscopy in a surgical
patient
• To keep abreast about the interventional procedures to put them to
good use in surgical patients

48. Thank you