Bronchoscopy in ICU: A Practical Guide Manoj K Goel, Ajay Kumar, Gargi Maitra
INDEX
Page numbers followed by b refer to box, f refer to figure, fc refer to flow chart, and t refer to table.
A
Abdominal distension 95
Acid-fast stain, modified 76
Acinetobacter baumannii 54
Adrenaline 106
Airway
Berman 118f
breathing and circulation, principles of 104
cells, predominantly 75
collapse, dynamic 90
diseases, obstructive 46
dynamics of lower 159
examination 139
extraluminal compression of 42
fistula 177
inflammation 41f
nomenclature of 12, 13t
obstruction 95, 181f
benign 35, 42
malignant 35, 42
pressure
bi-level positive 49, 88
continuous positive 88
expiratory positive 88
inspiratory 49
inspiratory positive 88
noninvasive bi-level 24
protection 153
resistance 25
size of 24
stenosis 101f
stenting 126
trauma 36
upper 1, 1f
bronchoscopic anatomy of 1
evaluation of 159
Alcohol flush 147
Alfentanil 62
Aluminum 111
Alveolar architecture, preservation of 111f
Alveolar arterial oxygen gradient 114f
Alveolar ground-glass opacities 111f
Alveolar hemorrhage 73
diffuse 77
sign of 78
Ambu aScope 20, 20f
American Foundation for Blind 56
American Society of Anesthesiologists 117
Aminobutyric acid 62, 63
Amoxicillin 55
Analgesia 154, 154b
Anesthesia 60, 61, 154
general 119
in bronchoscopy, monitoring during 61
topical 64
Argon plasma coagulation 20
Arm-brain circulation time 60
Arrhythmia 60, 135
Aspergillosis
allergic bronchopulmonary 48, 77, 104, 168f
bronchopulmonary 77
Aspergillus fumigatus 54
Aspiration 40
event, witnessed 41fc
pneumonia 82f, 162
Asthma
bronchial 48, 77
severe 48
Atelectasis 99
and collapse 39, 95
clinical presentation 96
investigations 96
management 97
bronchoscopy for 99
nonobstructive 95
obstructive 95
segmental 98
subsegmental 98, 99
treatment of 97
types of 95
Auramine 76
Autoimmune disease 124
Automated endoscope reprocessors 147, 147f
advantages 147
disadvantages 147
B
Bacteremia, transient 137
Bacteria 54
Bacteriological cultures 57
Bacteroides
fragilis 54
melaninogenicus 54
Balloon bronchoplasty 126, 127, 183, 183f
Balloon dilatation 127f
Balloon tamponade 106
Barotrauma 25
Barotrauma, risk of 31
Basal segments 165f, 166f
Benzodiazepines 62, 63, 119
advantage of 62
Biopsy 180
forceps 21f, 70f, 107f
open jaws of 71f
tip of 173f, 179f
types of 21f
Bleeding 137
active massive 169f
disorders 72
Blood
dyscrasia, uncorrectable 112
pressure 23
prevent aspiration of 106f
urea nitrogen 51
Bone marrow transplantation 111
Bowden mechanism 19
Brachytherapy
catheter 181f, 182f
endobronchial 181
Breathing sounds, abnormal 151
British Thoracic Society 64, 150
Bronchi
distal 72
lateral segmental 165f
medial segmental 165f
posterior segmental 164f
Bronchial artery embolization 106
Bronchial aspirate 56
Bronchial brushing 57, 157
Bronchial divisions, segmental 6f
Bronchial inflammation, severe 179f
Bronchial lavage 73, 167f, 168f
Bronchial mucosa, cicatrized hyperemic 171f
Bronchial stenosis 162, 177
Bronchial stump 179
after left upper lobectomy, dehiscence of 38f
Bronchial tree 67f, 69f
left 10
right 7
Bronchial washings 158
Bronchiectasis 42, 103, 104, 162, 171
Bronchiolitis obliterans 36, 77
Bronchitis
chronic 104, 169f
asthmatic 111
Bronchoalveolar lavage 20, 25, 34, 46, 48, 56, 57, 61, 72, 73, 76, 76b, 77, 86, 89, 136
diagnostic 29
fluid
analysis of 76fc
smears of 76b
indications of 73, 73b
organism identified in 76b
samples 57b
site of 74
technique 73
Bronchodilators, nebulised 61
Bronchomalacia 159, 161f, 162
Bronchopleural fistula 38f
closure of 35, 152
development of 37
postoperative 37
Bronchoscope 2, 6f, 14, 15f, 16, 41f, 67f, 68f, 71f, 85f, 98, 99, 99f, 104, 108f, 120f, 122f, 130f, 143, 144, 144f
care of 142
diameter 24
disposable flexible 20f
distal end of 108f
distal tip of 15f
flexible video 20f
handling of 66
hold tip of 67f
insertion
cord of 67f
tip of 72
light source of flexible 16f
lubricate insertion cord of 69f
newer 19
parts of 14
pediatric flexible 155t
precleaning of 143
reprocessing in stepwise manner 143fc
size of 24, 153
storage of 148f
suction port of 68f
tip of 66f, 69f, 71f
types of 14
video 14, 18, 19, 71
processor 16f
with water, rinsing of 145f
Bronchoscopic accessories, reprocessing 147
Bronchoscopic anatomy, cornerstone of 1
Bronchoscopic aspiration 98
Bronchoscopic cryosurgery 99
Bronchoscopic guidance 42
Bronchoscopic interventions 125, 126, 133
Bronchoscopic intubation 117, 119, 120
indications for 117b
Bronchoscopic laser 109
Bronchoscopic lung biopsy 92
Bronchoscopic management 126, 133
in postintubation tracheal stenosis 124
causes and risk factors of 124
management of 125
treatment of 126
types of 125
Bronchoscopic procedures 56, 86, 157
Bronchoscopic samples 68f
Bronchoscopic specimen quality, criteria for 56b
Bronchoscopic tamponade 106
Bronchoscopic techniques 103
Bronchoscopic toileting 98
Bronchoscopist satisfaction scores 64
Bronchoscopy 2, 24, 35, 39, 60, 62, 63t, 64, 66, 68f, 88, 97, 106, 121, 131, 139, 156, 157
adaptor 23
atlas 164
autofluorescence 20
carries 52
complications of 135b, 156, 156t
components of modern 14
contraindications of 139b, 155
during mechanical ventilation 80
indications 80
postprocedure care 85
preprocedure preparation 81
evolution of 60
in atelectasis, indications for 98b
in intensive care unit
indications of 35b
anesthesia and sedation during 60
indications of 34, 35, 98b
interventional 128
lung volume reduction 20
mask 118f
monitoring during 29
plays 103
premedication for 61
preparation 91
procedure 61, 91
suite 74
team 156
typical 85f
with noninvasive ventilation, steps of 49b
Bronchospasm 74, 135, 136
Bronchus
anterior segment 11
apicoposterior 11
bleeding 108f
dilated 171f
intermedius 8, 8f, 9f, 175f, 179f, 182f
left main 11f
lingular 11f
segmental 12f
lower lobe
left 12, 12f
right 10
obstruction of left main 40f
right
main 7
middle lobe 9, 10f
subsegmental 74
tooth occluding right intermediate 82f
upper lobe
left 11, 11f
right 8, 164f
Brush biopsy 180f
C
Capillary pressure 124
Carbapenems 55
Carbon monoxide 115
Carcinoma
bronchoalveolar 73
bronchogenic 73, 134
Cardiac arrhythmias 29, 92, 136
Cardiac chambers 162
Cardiac index 50
Cardiovascular depressant effects, minimal 62
Cardiovascular effects 27
Cardiovascular perturbations 31
Carina 7
lower end of 169f
widening of 173f, 176f
Catheter mount 69f, 157f
Cauliflower growth 173f
Cefepime 55
Ceftriaxone 55
Cement 111
Cerebral edema 27
Cervical segment ends 7
Cetacaine spray 119
Chest
computed tomography 111f, 114f, 132f
physiotherapy 97
trauma, blunt 36
ultrasound 96
X-ray 40f, 105
Chlamydia 75
Chou's classification 39t
Churg-Strauss syndrome 77
Clavulanate 55
Clopidogrel 50
Coagulopathy 50, 104
Coccidioides immitis 54
Cold saline lavage 106
Comorbid diseases 135, 139
Complete blood count 104, 105
Conchae 2
Contrast-enhanced computed tomography 105
Cor pulmonale 110
Cormack-Lehane score 118
Coronavirus 54
Craniofacial trauma 152
Crazy paving 111
Critical care medicine 60
Cryoadhesion 152
Cryoprecipitate 140
Cryoprobe 127
Cryotherapy 101f
Cryptococcus neoformans 76
Cryptogenic organizing pneumonia, acute 77
Cuff pressure 124
Cystic lung disease 104
Cytology 57, 77
brush 21, 22f
tip of 158f
Cytomegalovirus 54
pneumonia 55
D
Debulk tumor mass 182f
Desamino-8-D-arginine 51
Dexmedetomidine 64, 119
Diode laser 183f
Disinfection 145
Double-lumen tube 110, 117
Drug administration 128
Drug toxicity 73
Dry bronchiectasis 171f
Dry cough 114f
Dumon stents 128, 128f
Dyspnea 114f
severe 111
E
Echocardiography, transesophageal 131
Edema
cardiogenic pulmonary 88
mucosal 168f, 170f
Electrocardiography, continuous 23
Electrocautery 181
knife 127f
Electromagnetic navigation 20
Emphysema, obstructive 42
End-expiratory pressure, positive 25, 46, 47, 48, 74, 138, 151, 153
Endobronchial balloon 107f
tamponading 107f
Endobronchial biopsy 158
forceps, ends of 158f
Endobronchial brushings 86
Endobronchial lesions 109
Endobronchial needles 21
Endobronchial photocoagulation techniques 108
Endobronchial tamponading 108
Endobronchial ultrasound 15, 57, 86
bronchoscope 15f, 19f
Endoscope, flexible 142
Endoscopy 131
mask 118f
Endotoxins 137
Endotracheal aspirate 75
Endotracheal intubation 167f, 177f, 178f, 183f
double-lumen 112
Endotracheal suctioning, application of 26
Endotracheal tube 24, 29, 39, 41f, 69f, 85f, 104, 118, 120f, 121, 121f, 122f, 142, 150, 168f
double-lumen 106f, 112, 113f
natural curve of 69f
placement of 152
Enteral nutrition 55
Enzyme-linked immunosorbent assay 57
Eosinophilia 77
Eosinophilic pneumonia 73
acute 77
chronic 77
Erythrocytosis 78
Esophageal growth 180f
Esophageal stent 130f, 131
placement 134
Esophagectomy 177f
Esophagus, carcinoma 39f, 176f, 177f, 180f
Ethylene oxide sterilization 147
Exacerbations, acute 88
Extrapulmonary malignancies 73
F
Fentanyl 62, 63
Fiberoptic bronchoscope 15f, 29, 37, 46, 47, 47t, 48, 49, 50, 50f, 50fc, 51t, 52, 91f, 95, 107f, 117, 139, 151
handling of 66
typical 18f
Fiberoptic bronchoscopy
contraindications for flexible 155b
flexible 29, 34, 52, 140, 152, 154b, 155
in mechanically ventilated patient 47fc
pathophysiological consequences of 46fc
in specific medical conditions 47t
indications of 49b
monitoring after 32
routes of insertion of flexible 155b
sedation and analgesia during flexible 154b
technique of 66
with coagulopathy 51t
Fiberoptic
bundles 18
intubation 117, 122
principle of 16, 18f
Fibrosis, idiopathic pulmonary 77
Fistula
formation 128
large
malignant 177f
tracheoesophageal 39f
Fleshy vascular growth 174f
Flexible bronchoscope 14, 112, 144f, 150
leak testing 19
portable light source of 16f
Flumazenil 62
Fluorescent antibody testing, direct 76
Fluoroscopy 34
Foamy macrophages 78
Fogarty balloon catheter 106, 107f
Food and Drug Administration 145, 146t
Forceps 21
biopsy 180f
Foreign body 42, 162, 179
aspiration 163f
bronchoscopic removal of 82f
diverticulum 179f
long-standing 42
removal of 100f, 152
Fospropofol 64
Fresh frozen plasma 48, 140
Fungal infections 73, 77
Fungating growth 175f
Fungi 54
Fusobacterium nucleatum 54
G
Gas exchange 26
Gastric pull-up surgery 177f
Gastrointestinal balloon dilator catheter 183f
Gastrointestinal endoscopy, upper 39
Gastroscopes 19
Gastrotracheal fistula 177f
German Society of Hematology and Medical Oncology 57
Glottic area 5
bronchoscopic view of 5f
Glue therapy 107
Glutaraldehyde 145, 146
Gram stain 57, 76
Granulation tissue 161f
formation 36f
Granulomas 173f
Grillo's rule 125
H
Haemophilus influenzae 54
Halogen 19
Head injury, traumatic 31
Heart failure, congestive 104
Hematological malignancy 51
Hemidiaphragm
elevation of 96
right 96f
Hemodynamic
changes 27
collapse 48
instability 96
Hemoptysis 42, 103, 109
active 166f
bronchoscopic management of 103
causes of 103
common causes of 104b
management of 104, 105fc
recurrent 171f
Hemorrhage 169, 174f
petechial 169f
Hemosiderin laden macrophages 78
Herpes simplex 54
High-resolution computed tomography 105
Hilar displacement 96
Histoplasma capsulatum 54, 76
Human immunodeficiency virus, bronchoscopy in 35b
Human metapneumovirus 54
Hydatid cyst 104
Hydrogen peroxide 145
Hydropneumothorax 114
Hypercapnia 26, 92, 136
Hypercarbia 31, 32
Hyperemia 168f, 170f
Hypertension 60
Hypothermia 74
Hypoventilation 95, 136
Hypoxemia 26, 31, 121, 136
refractory 92
severe 89
Hypoxia, intraoperative 114
I
Idiopathic hypereosinophilic syndrome 77
Imidazobenzodiazepine derivative 62
Immunocompromised host 55, 55b, 88, 151
bronchoscopy in 54
Immunocompromised state 51
Infections 138
bacterial 73
diagnostic of 76b
granulomatous 131
Inflammation 168
acute 168f
Inflammatory mediators, release of 137
Inflation catheter technique 48
Influenza 54
A virus 76
B virus 76
Inhalation burn injury, bronchoscopic findings of 39t
Inhalational exposure 111
Inhalational injury 52
Insertion cord, flexible 15
Inspiratory pressure 31
level 25
Intensive care unit 24, 34, 49, 73, 73b, 88, 96, 105, 118, 124, 150, 151
Interlobular septal thickening 111f
International normalized ratio 51, 137
Interstitial lung disease 36
acute 77
Interstitial pneumonia, acute 36, 77
Interventional pulmonology procedures 71
Intrabronchial growths, multiple 175f, 176f
Intracranial pressure 51, 60, 138
elevated 135
monitoring 150
raised 51, 138
Intracytoplasmic cytomegalovirus 55
Intraluminal growth 43f
Intranasal trauma 72
Intrinsic obstruction 43f
Intubation injury 36
Invasive aspergillosis 55
Ischemic heart disease 46, 48, 50, 50fc
anticoagulants in 50fc
J
Jackson-Huber classification 12
K
Kaposi sarcoma, endobronchial 35
Kidney function tests 105
Kinetic therapy 97
Klebsiella pneumoniae 54
L
Laryngeal cleft 160f
Laryngeal edema
postextubation 36f
postintubation 36f
Laryngeal mask airway 23, 157, 157f, 158f
selection guidelines 157t
Laryngeal structures 121
Laryngocele 160f
Laryngomalacia 160f
Laryngopharynx 3
Laryngospasm 121, 135, 136
Larynx 2, 119
anatomy of 4f, 5f
bronchoscopic view of 5f
evaluation of 159
Laser photocoagulation 182
Leak test 19, 143
Legionella 75
pneumophila 54, 76
Leiomyoma, endobronchial 163f
Leukemia 111
Lidocaine 64, 154
Light source 15, 16f, 18
Light transmission cord 15
Lignocaine 119
gel 119
jelly 69f
solution 64
Liquid chemical germicide 145b
Liver
disease 51
function tests 105
Lobar atelectasis 98
Lobar emphysema, congenital 162
Lorazepam 62
Lower lobe
basal segments
of left 12f
of right 10f
Lumen of trachea, severely compromised 180f
Lung
abscess 104
carcinoma 173
compliance 26
diffusing capacity of 115
disease 77
diffuse 36
drug induced 77
infiltrates
febrile neutropenic patients with 57b
in immunocompromised host 73
injury, inhalational 112
insufflation, method of 99
mechanics 25
parenchyma 112
pulse sign 96
segments 72
squamous cell carcinoma of 169f
ultrasound 97f
Lymph node 162
enlargement, subcarinal 173f, 176f
Lymphangitis carcinomatosis 73
Lymphocytosis 77
Lymphoma 73, 176f
Lysinuric protein intolerance 111
M
Macrophages 78
Massive hemoptysis 42, 81f
source of 103
Mechanical ventilation 82f, 83f, 161f
Mediastinal emphysema 130
Mediastinal lymph node 172f
Mediastinal mass 162
Membranous trachealis muscle 164f
Mercedes-Benz cuts 126
Metallic stent, self-expandable 127, 133f
Metastatic lymph node enlargement 181f
Micronodular opacities 36
Midazolam 62, 63
use of 62
Minocycline 77
Mitral stenosis 43f, 104
Molecular tests 57
Montgomery T-tube 128, 128f
Moraxella 138
Mouth 119
bronchoscopic anatomical boundary of 2f
Mucoid secretions 167f, 176f
Mucolytic agents 97
Mucopurulent secretions 168f, 171f
Mucosal bleeding 169f
diffuse 169f
Mucosal injury 169f
Mucosal necrosis 128
Mucosal overgrowth 180f
Mucus extractor 68f
Mucus gland pits 171f
Mucus plugs 48, 111
removal of 99
Muscle relaxation 153
Mycobacteria 73, 75
Mycobacterium
avium-intracellulare 54
tuberculosis 35, 54, 56, 76
Mycoplasma 75
pneumoniae 76
Myocardial dysfunction 135
Myocardial infarction 48, 50
Myocardial ischemia 92
N
N-acetylcysteine 110
Naloxone 63
Narcotics, synthetic 151
Nasal cavity, lateral wall of 2f
Nasal intermittent mandatory ventilation 48, 49
Nasal intubation 120
Nasal mucosa 119
Nasopharyngeal mass 159f
Nasopharynx 3, 119, 138
anatomy of 3f
Neodymium-doped yttrium aluminum garnet, use of 108
Neoplasm 104
Neurotrauma 82f
Neutrophilia 77
N-galactomannan test 35
Nitrofurantoin 77
Nocardia 54, 76
Nodular growth 174f
Noninvasive ventilation 49, 88, 91f, 92
assisted bronchoscopy 90, 92f
causes of 49
interfaces 90
protocol 91
O
Obstructive airways disease, chronic 168f
Obstructive pulmonary disease, chronic 48, 49, 49b, 88, 136, 170
Olympus MAF mobile bronchoscope 158f
Opioids 62, 63
Optical coherence tomography 20
Oral
cavities 2f
intubation 118f
Orlipressin 106
Oropharynx 2, 3, 4f, 119
anatomy of 4f
Orthophthalaldehyde 145
Ovassapian fiberoptic intubating airway 118f
Oxygen
arterial partial pressure of 136
saturation 150
supplementation 74
P
Paragonimiasis 104
Parainfluenza 54
Paranasal sinuses 2
Parasites 54
Parasitic lung diseases 104
Parenchymal disease, severity of 26
Partial thromboplastin time 48
Patchy consolidation, bilateral 36
Peak inspiratory pressure 25
Peak-end expiratory pressure 60
Pediatric ambu bag 99f
Pediatric critical care, bronchoscopy in 150
Pediatric intensive care unit, bronchoscopy in 150
Penicillin 77
Peribronchoscopy period 27
Periodic acid-Schiff 76
accumulation of 111f
Persistent cough 162
Phagocytose erythrocytes 78
Pharmacological sedative agents 64
Pharyngeal wall, posterior 120f
Pharynx, anatomy of 3f
Photodynamic therapy 20
Pierre Robin syndrome 152
Pig bronchus 166f
Piperacillin 55
Plateau pressure 25
Pneumocystis
carinii 54, 75, 76
carinii pneumonia 55
diagnosis of 73
jirovecii 55, 57
pneumonia 31
Pneumomediastinum 42
Pneumonia 89, 104, 168f
bacterial 55
organizing 36
recurrent postobstructive 82f
ventilator associated 73, 75
Pneumonitis
acute hypersensitivity 77
hypersensitivity 73
Pneumothorax 42, 60, 114, 137
Polymerase chain reaction 55, 57, 75
Polypoidal growth 173f
Polyurethane particles 106
Polyvinyl alcohol particles 106
Postbronchoscopy
care 92
fever 137
Postsynaptic membrane, hyperpolarization of 63
Post-tracheostomy tracheal stenosis 124
Potassium hydroxide 57
preparation 76
Prebronchoscopy levels 31
Pressure ulceration 167f
Propofol 63, 64, 119
infusion syndrome 63
Protein debris 144
Prothrombin time 48
Pseudomonas aeruginosa 54, 138
Pulmonary alveolar
pressure 25
proteinosis 73, 76, 110, 111, 111f
Pulmonary arterial hypertension 48, 50
Pulmonary artery flotation catheter 107f
Pulmonary atelectasis, management of 101fc
Pulmonary disorders 34
Pulmonary embolism 104
Pulmonary hypertension 27
moderate 50
severity of 50
Pulmonary infection 34, 73, 88
Pulmonary infiltrates
in immunocompromised host, infective causes of 54b
noninfective causes of 55b
nonspecific 36
Pulmonary insufficiency 135
Pulmonary interventions 39
Pulmonary lung disease, diffuse 73
Pulmonary malignancy 73
Pulmonary tuberculosis 104
Pulse oximetry 23, 61, 150
Purulent bronchiectasis 172f
Purulent bronchitis 171f
R
Radial cuts 126
Radiation, endobronchial 181f
Ramsay sedation scale 61b
Reflux disease 124
Remifentanil 64
Renal elimination 62
Renal insufficiency 51
Respiratory depression, risk of 119
Respiratory distress 83f, 92
syndrome 151
acute 77, 136
Respiratory failure 49, 82f
acute 88
hypoxemic 93
Respiratory rate 23
Respiratory syncytial virus 54, 76
Rhinovirus 54
Rhodamine 76
Rhodococcus equi 54
Richmond agitation-sedation scale 31
Rigid bronchoscope 14, 80, 86, 104
Riker sedation-agitation scale 31
Road traffic accident 38f
S
Saline instillation 74
Sarcoid granulomas 173f
multiple 173f
Sarcoidosis 73, 173
Secretions 167
Sedation 119, 135, 138, 153, 154, 154b
Sevoflurane 119
Silica 111
Silicone
stent insertion 128
stent placement 82f
Y-stent covering fistula 82f
Silver methenamine 76
Smoke inhalation injury 37
Smooth extrinsic compression 176f
Sodium iodide 110
Specimen brush, protected 57, 7577
Staphylococcus 138, 148
coagulase-negative 148
Stem cell transplant, allogeneic 57
Stenosis
complex 125, 125f
extrinsic 43f
initial assessment of 126b
length of 126, 128
position of 126
simple web-like 125f
subglottic 124, 159
types of 126
Stent in situ 125
Stomal site, sepsis of 124
Streptococcus 138
pneumoniae 54
Stridor 82f, 162b
Strongyloides stercoralis 54, 76
Subglottic area 5
Subglottic web 160f
Supraglottic area 4
bronchoscopic view of 4f
Swivel adapter, dual-axis 157, 157f, 158f
Systemic inflammatory response syndrome 137
T
Tachyarrhythmias 106
Tachycardia 60
Tazobactam 55
Tenacious mucoid secretions 171f
Terlipressin 106
Tetracaine 119
Thoracic surgery, video-assisted 55
Thrombocytopenia 51, 72
Tidal volume 25, 151, 153
Titanium 111
Tortuous stenosis 127
Toxoplasma gondii 54, 76
Trachea 6, 7f, 119, 130f
bifurcation of 164f
bronchoscopic view of 8f
evaluation of 159
extrinsic compression of 43f
growth in 183f
lower end of 169f
postintubation stricture of segment of 37f
Tracheal aspirate 76
blind 75
Tracheal candidiasis 162
Tracheal dilation 131
Tracheal intubation 131
Tracheal lumen 83f
Tracheal mucosa 124, 172f
ischemia of 124
Tracheal stenosis 37f, 82f, 152, 159, 178, 178f
postintubation 124, 125
web-like 181f
Tracheal stenting 131
Tracheal wall, tear of posterior 38f
Tracheobronchial tree 1, 6, 44, 52
bronchoscopic anatomy of 1
Tracheobronchomalacia 90, 159
Tracheoesophageal fistula 37f, 39, 39f, 82f, 130, 132f, 133f, 134, 176f
benign 131b, 177f
bronchoscopic
management of 130
view of 39f
causes of benign 131b
closure 35
corrosive injury-related 132, 132f
features 132
infections related 131
infectious 133
investigations 132
malignant 130f, 133
management 132
noninfectious benign 132
postinfectious 133f
postintubation 130, 131b, 131f
postsurgical 131
risk factors for postintubation 131b
traumatic 131
Tracheomalacia 126, 159, 161f, 162, 178, 178f
Tracheostomy 83f, 178f
percutaneous 42, 131
tube 41f
Transbronchial biopsy 51, 57, 72, 86, 158
Transbronchial lung biopsy 46, 48, 51, 137
fiberoptic bronchoscopy with 51t
Transbronchial needle 21
aspiration 21, 57, 86
Transcutaneous capnography 61
monitoring, use of 61
Trauma 52
penetrating 131
Traumatic complications 135, 136
Traumatic intubation 130
Trendelenburg position 113
Tubercular granulomas 172f
Tubercular stricture 172, 177f
Tuberculosis 54, 56, 105, 170f, 172, 172f
endobronchial 57, 101f, 162
Tuberculous bronchial stenosis 163f
Tumor
endobronchial 42, 162
mass 182f
U
Upper lobe segments, right 9f
V
Vagal tone 62
Vallecular cyst 159f
Varicella zoster 54
Vascular growth, lobulated 174f
Vascular ring 162
Vascular signs 96
Vascular tumor 83f
Vasovagal syncope 135
Ventilation 61, 74
physiological effects of noninvasive 88
requiring noninvasive 61
Ventilation-assisted bronchoscopy
contraindications for noninvasive 90
indications for noninvasive 89
Ventilation-assisted fiberoptic bronchoscopy
contraindications for noninvasive 90b
indications of noninvasive 90b
Ventilation-perfusion
imbalance 136
mismatch 114
Ventilator settings 151
Viruses 54
Vocal cord 6f, 166
normal 164f
palsy
left 167f
right 166f
postintubation pressure ulceration of 36f
W
Wang's TBNA needle 22f
Wedging scope 74
Wheeze 159
bilateral 162
causes of bilateral 162b
localized 38, 162b
unilateral 162, 162b
Whole lung lavage 110
procedure 112
X
Xenon lamps 19
Y
Yamashita Japanese classification 12
Z
Ziehl–Neelsen stain 57
×
Chapter Notes

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Bronchoscopic Anatomy of Tracheobronchial TreeCHAPTER 1

Manoj K Goel,
Lokender Kumar,
Surya Kant
 
INTRODUCTION
Bronchoscopy is a diagnostic and therapeutic procedure to visualize the airway and its pathological alterations. Knowledge of the upper and lower respiratory tract structures is the cornerstone of bronchoscopic anatomy. Jakson and Huber1 in the year of 1943 were the first ones to recognize the importance of a systematic classification of the tracheobronchial tree. In fact, their classification is the basis of the international nomenclature system approved by the British Thoracic Society in 1949.2 The aim of this article is to describe the gross structural anatomy visible while doing a flexible bronchoscopy, during its passage, when the patient is in supine position. Bronchoscopy involves examination of both upper airway and lower respiratory tract. However, in intubated and tracheostomized patients, the upper airway is bypassed and bronchoscopic examination of only lower respiratory tract is possible beginning from the lower part of trachea.
 
UPPER AIRWAY
The bronchoscopic anatomy of upper airway includes mouth, nose, pharynx, and larynx. The mouth and nasal cavity are separated from each other by soft and hard palate. The bronchoscope can be introduced through nose as well as mouth leading to oropharynx, and then onwards further into respiratory passages (Fig. 1).
zoom view
FIG. 1: The upper airway.
 
Mouth
  • The bronchoscopic anatomical boundary of mouth is made by lips anteriorly, hard and soft palate superiorly, floor of the tongue inferiorly, and the oropharynx posteriorly (Fig. 2)
  • Via the oral approach, bronchoscope is introduced in-between the lips, passed through the oral cavity, over the tongue and below the hard and soft palates, to the oropharynx and then to larynx.
 
Nose
  • The nose begins anteriorly with two nostrils and communicates posteriorly with the nasopharynx (Fig. 3)
  • The palate separates nasal cavity above and oral cavity below (Figs 1 and 4)
  • The nasal septum divides nasal cavity into two nasal fossae (Fig. 3)
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FIG. 2: Bronchoscopic anatomical boundary of mouth.
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FIG. 3: Skull showing the frontal view of nasal passage.
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FIG. 4: Sagittal view showing the palate dividing the nasal and oral cavities, while pharynx is seen as the common conduit to both respiratory and alimentary tract.
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FIG. 5: Sagittal view showing the three turbinates in the lateral wall of nasal cavity.
  • The lateral wall of nasal cavity has three bony projections called turbinates or conchae. These are described as superior, middle, and inferior turbinates. The superior turbinate is not visible during bronchoscopy (Fig. 5)
  • Going through the nasal cavity the turbinates are seen laterally and the nasal septum medially. Therefore, each nasal cavity is bounded medially by the nasal septum, laterally by the three turbinates, and inferiorly by the hard palate (Figs 1, 3 and 5)
  • The area under each turbinate is called meatus in which paranasal sinuses open. These are called superior, middle, and inferior meatus respectively, which allow air to be humidified and warmed-up to the lower airway35
  • Via the nasal approach, the bronchoscope is inserted through nostrils, passed usually below the inferior turbinate or between the middle and inferior turbinates to the nasopharynx, over the uvula to the oropharynx, and then to larynx.
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Pharynx
  • The pharynx is a muscular tube that connects the nasal and oral cavities to the larynx and esophagus. Pharynx is unique in a way that it is common to both the alimentary and the respiratory tracts (Fig. 4)
  • The pharynx begins at the base of the skull and ends inferior to the cricoid cartilage
  • It is comprised of three parts6 (Fig. 6) from superior to inferior as follows:
    • Nasopharynx
    • Oropharynx
    • Laryngopharynx.
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FIG. 6: Anatomy of pharynx.
 
Nasopharynx
  • The nasopharynx is found between the base of the skull above and the soft palate below, and is a continuation of the nasal cavity (Fig. 7).
 
Oropharynx
  • The middle part of pharynx called oropharynx extends anteriorly between soft palate above and base of tongue below; and from tip of uvula to epiglottis behind (Fig. 8).
 
Laryngopharynx
  • The most distal part of the pharynx also called laryngopharynx or hypopharynx, lies posterior to larynx between the superior border of the epiglottis and inferior border of the cricoid cartilage (C6), at which point it becomes continuous with the esophagus (Fig. 8)
  • During routine bronchoscopy, hypopharynx is not negotiated, as from oropharynx the bronchoscope is directly passed into larynx.
 
Larynx
  • The larynx is a 5–7 cm long communicating structure between the upper and lower respiratory tract7
  • The larynx starts at the tip of epiglottis and ends at the lower border of cricoid cartilage, consisting of three areas (Fig. 9) as follows:
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    FIG. 7: Anatomy of nasopharynx in relation to the surrounding structures.
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    FIG. 8: Anatomy of oropharynx in relation to the surrounding structures.
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    FIG. 9: Anatomy of larynx.
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    FIG. 10: Bronchoscopic view of supraglottic area as seen from the oropharynx.
    1. Supraglottic area
    2. Glottic area
    3. Subglottic area.
 
Supraglottic Area
  • From oropharynx during bronchoscopy, the supraglottic area is seen consisting of epiglottis, vallecula, and base of the tongue (Fig. 10)
  • The epiglottis is a leaf-shaped structure arising from the base of tongue. It is the first laryngeal structure seen when the bronchoscope is in the oropharynx
  • The base of the tongue joins the anterior surface of the epiglottis and forms the median and lateral glossoepiglottic folds
  • The space between the median and lateral glossoepiglottic folds called vallecula, which is a pouch like fold between the epiglottis and the base of the tongue
  • Moving further posteriorly and inferiorly, one can see the aryepiglottic folds connecting the epiglottis and arytenoid cartilages. There are bumps in the mucosa of aryepiglottic folds representing the underlying cuneiform and corniculate cartilages (Figs 11 and 12)
  • Lateral to the aryepiglottic folds are the piriform fossae of the pharynx. The piriform sinuses are pyramid shaped with the bases superior at the level of the laryngeal inlet and the apices at the inlet of the esophagus (Fig. 12)
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FIG. 11: Anatomy of larynx as viewed from the supraglottic area.
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FIG. 12: Bronchoscopic view of larynx as seen from the supraglottic area.
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FIG. 13: Bronchoscopic view of glottic area.
  • Hence, visualizing from oropharynx, the larynx is bounded anteriorly by the free border of the epiglottis, laterally by aryepiglottic folds, and posteriorly by the corniculate tubercles of the arytenoid cartilages (Figs 11 and 12).
 
Glottic Area
  • The glottic area corresponds with the vocal cords (Figs 11 and 13)
  • From the aryepiglottic folds, there are thick folds of mucous membrane going up to the true vocal cords. These are called vestibular folds, ventricular folds, or false vocal cords. The vestibular fold is formed by the vestibular ligament extending from lateral wall of epiglottis to arytenoid cartilage
  • The true vocal cords lie below the false vocal folds, extending from the anterior surface of the arytenoid cartilage to the thyroid cartilage. The true vocal cords are glistening shining, ivory or pearl white colored, which meet anteriorly to form anterior commissure just below the laryngeal surface of epiglottis. Posteriorly, the true vocal cords are separated from each other articulating with vocal process of arytenoid cartilage. This intercartilaginous area is called posterior commissure. The bronchoscope is introduced between the true vocal cords as near to posterior commissure as possible
  • Above the true vocal cords is the ventricle, superiorly bound by the false vocal cords
  • The opening between the two true vocal cords is called the rima glottidis, or glottis through which the bronchoscope is passed further down the airways.
 
Subglottic Area
  • The subglottic space begins from the inferior border of the true vocal folds and terminates 2 cm below at the level of the cricoid cartilage (Fig. 14)
  • The cricoid is the lower margin of the larynx and forms the only complete cartilage ring in the airway (Fig. 15)
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FIG. 14: Subglottic area viewed as the bronchoscope is negotiated across the vocal cords.
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FIG. 15: Subglottic area showing cricoid forming the complete cartilage ring.
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FIG. 16: Trachea dividing into major bronchi and then further subsequent lobar and segmental bronchial divisions.
  • From below the cricoid cartilage, the lower respiratory tract also called the tracheobronchial tree begins.
 
TRACHEOBRONCHIAL TREE
The lower respiratory tract forms the tracheobronchial tree, which is like a branching of a tree. It begins with trachea and then divides into right and left bronchial tree going into right and left lungs, respectively (Fig. 16).
The right lung has three lobes called right upper, middle, and lower lobes. The right upper lobe has three segments—apical, anterior, and posterior segments. The right middle lobe has two segments called medial and lateral segments. The right lower lobe consists of five segments, which include one superior segment and four basal segments termed as medial, anterior, lateral, and posterior basal segments. To summarize, the right lung has three lobes supplied by respective lobar bronchi and 10 segments supplied by their respective segmental bronchi (Fig. 17).
The left lung has two lobes called left upper and left lower lobes. The left upper lobe has two divisions called upper division and lingua. The upper division of left upper lobe has two segments termed as apicoposterior and anterior segments. The lingular division has two segments called superior and inferior lingular segments. The left lower lobe consists of four segments, which include one superior segment and three basal segments called anterior, lateral, and posterior basal segments. To summarize, the left lung has two lobes supplied by their respective lobar bronchi and eight segments supplied by their respective segmental bronchi (Fig. 17).
 
Trachea
  • Trachea is the initial segment of the lower airway that projects onto the spine from C6 to the level of T5.8 It is a cartilaginous cylindrical tube that extends from the cricoid cartilage to the carina9 (Fig. 18)
  • As it passes downwards, it follows the curvature of the spine and courses slightly backward. Near the tracheal bifurcation, it deviates slightly to the right
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FIG. 17: Segmental anatomy.
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FIG. 18: Trachea.
  • One-third of the trachea is extrathoracic and two-thirds is intrathoracic. The extrathoracic or cervical segment ends at the sternal manubrium and encompasses about the first six tracheal rings
  • The length of the trachea varies according to age. In neonates it is 3 cm, in the pediatric population the range is 7–10 cm,10 and in adults it is approximately 15 cm
  • The diameter of trachea varies in accordance with the gender of the patient. In men, the average diameter of trachea is 22 mm, the coronal diameter is 13–25 mm, and sagittal diameter is 13–17 mm. The tracheal diameter in men is somewhat larger as compared to women who have average diameter 19 mm, coronal 10–21 mm, and sagittal diameter 10–23 mm.11 The average diameter in neonates and pediatrics age group is 6 mm and 10 mm, respectively
  • In adults, the trachea is supported anterolaterally by 16–20 incomplete C-shaped cartilages
  • The anterolateral wall is united posteriorly by a tracheal membrane with no cartilage and is supported by the membranous trachealis muscle,12,13 which overlies esophagus. The membranous trachealis muscle allows expansion of esophagus during deglutition (Fig. 19).
 
Carina
The normal carina is sharp vertical ridge like projection in the center, which causes bifurcation of trachea into right main bronchus at 25–30° and left main bronchus at 45° angle from the midline (Fig. 20).
In children, the carina is usually more displaced to the right and with time it becomes more medial and the angulation tends to be more obtuse.
 
Right Bronchial Tree
The right bronchial tree begins with right main bronchus after bifurcation of carina.
 
Right Main Bronchus
  • The right main bronchus (Fig. 21) is short and more vertical compared to left main bronchus. In men, the average length of right main bronchus is 2.0 cm, whereas it is approximately 1.5 cm in women. The average diameter is 17.5 mm in men and 14 mm in women
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FIG. 19: Bronchoscopic view of trachea.
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FIG. 20: Carina dividing lower end of trachea into right and left major bronchi.
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FIG. 21: Right main bronchus as seen from near the carina.
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FIG. 22: Right main bronchus seen dividing into right upper lobe bronchus and bronchus intermedius with right carina 1 (RC1) in the middle.
  • Right main bronchus divides into two divisions (Fig. 22):
    • Right upper lobe bronchus
    • Bronchus intermedius
  • The secondary carina dividing the right upper lobe from the bronchus intermedius is called the Right Carina 1 or RC-1 (Fig. 22).
 
Right upper lobe bronchus
  • The right upper lobe bronchus is seen originating from the right lateral wall of right main bronchus
  • Right upper lobe bronchus usually branches into three segmental bronchi (Fig. 23) termed as:
    • Apical segment bronchus
    • Anterior segment bronchus
    • Posterior segmental bronchus
  • The openings of the three segmental bronchi of right upper lobe form a triangle. The anterior and posterior segment bronchi are together seen opposite to each other, while the apical segment bronchus forms the apex of the triangle.
 
Bronchus intermedius
  • After generating the right upper lobe bronchus, right main bronchus becomes the bronchus intermedius (Fig. 24), which extends for approximately 2–2.5 cm and then splits into two divisions (Fig. 25):9
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    FIG. 23: Right upper lobe segments.
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    FIG. 24: Bronchus intermedius entry.
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    FIG. 25: Bronchus intermedius is seen dividing into right middle lobe and right lower lobe bronchi with right carina 2 (RC2).
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    FIG. 26: View from bronchus intermedius shows three openings almost at the same level with right middle lobe bronchus and superior segment of right lower lobe opposite to each other while the common opening of right lower lobe is in between the two.
    • Right middle lobe bronchus
    • Right lower lobe bronchus
  • The length of right lower lobe bronchus is very small and it immediately gives off its superior segment. Therefore, the bronchoscopic view from the bronchus intermedius shows three openings appearing almost at the same level (Fig. 26). The medial opening is of right middle lobe bronchus, the lateral opening just opposite to right middle lobe bronchus is superior segment of right lower lobe and in-between the two is the opening of remaining right lower lobe bronchus
  • The secondary carina between the right middle lobe bronchus and the bronchus to the right lower lobe is named the Right Carina 2 or RC-2 (Fig. 25).
 
Right Middle Lobe Bronchus
  • The right middle lobe bronchus emerges anterolateral to bronchus intermedius with a length of 1–2 cm (Figs 25 and 26)
  • It divides into two divisions (Fig. 27):
    1. Lateral segment bronchus
    2. Medial segment bronchus
  • The lateral segment bronchus is visualized more distally as compared to medial segment bronchus, which originates more obliquely.
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FIG. 27: Right middle lobe bronchus and its two divisions.
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FIG. 28: Right lower lobe bronchus seen dividing into its superior segment and the common division of four basal segments.
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FIG. 29: Basal segments of right lower lobe.
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FIG. 30: Left main bronchus as seen from the level of carina.
 
Right Lower Lobe Bronchus
  • Right lower lobe bronchus (Fig. 28) divides into five segmental bronchi:
    1. Superior segment bronchus
    2. Medial basal segment bronchus
    3. Anterior basal segment bronchus
    4. Lateral basal segment bronchus
    5. Posterior basal segment bronchus
  • The superior segment bronchus of right lower lobe arises posteriorly opposite and across to the origin of middle lobe bronchus. The remaining four basal segments of right lower lobe arise from a common division, which is seen in-between the openings of right middle lobe bronchus and superior segment bronchus of right lower lobe (Fig. 26)
  • The medial basal segment bronchus arises a bit more distally on the medial wall of right lower lobe bronchus separately from subsequent division of right lower lobe, which finally divides into anterior basal, lateral basal, and posterior basal segment bronchi (Fig. 29).
 
Left Bronchial Tree
  • The left bronchial tree begins with left main bronchus after bifurcation of carina (Figs 20 and 30)
  • The left main bronchus is usually 4–5 cm long. Its lumen is narrow and relatively horizontal as compared to right main bronchus11
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    FIG. 31: Left main bronchus seen dividing into left upper lobe and left lower lobe bronchi with left carina 1 (LC1) in the middle.
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    FIG. 32: Left main bronchus seen dividing into left upper lobe and left lower lobe bronchi with left carina 1 (LC1) in the middle. Further divisions of left upper lobe bronchus also visible.
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    FIG. 33: Left upper lobe bronchus seen dividing into its upper division and lingular bronchus by Left carina 2 (LC2).
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    FIG. 34: Upper division of left upper lobe bronchus and its two divisions.
  • The left main bronchus divides into two lobar bronchi for their respective lobes (Fig. 31) which are:
    1. Left upper lobe bronchus
    2. Left lower lobe bronchus.
 
Left Upper Lobe Bronchus
  • It divides into two divisions (Figs 32 and 33) as:
    1. Upper division bronchus
    2. Lingular bronchus, which is also called lower division bronchus.
  1. Upper division of left upper lobe bronchus:
  • The upper division of left upper lobe is lateral to lingular division
  • This divides into two segmental bronchi (Fig. 34) called:
    1. Apicoposterior bronchus
    2. Anterior segment bronchus
  • The apicoposterior bronchus as the name suggests is most apicoposterior and lateral. It subsequently divides into the:
    1. Apical subsegment bronchus
    2. Posterior subsegment bronchus
  • The subcarina separating the upper division of left upper lobe bronchus from the lingular segment is termed Left Carina-1 or LC-1(Fig. 32).
  1. Lingular division:
  • The lingular division is seen slightly inferomedial to upper division (Figs 32 and 33)
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FIG. 35: Lingular segmental bronchus and its two divisions.
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FIG. 36: Left lower lobe bronchus seen dividing into its superior segment and the common opening of three basal segments.
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FIG. 37: Basal segments of left lower lobe.
  • It is 2–3 cm long and divides into two divisions (Fig. 35) termed as:
    • Superior lingular segment bronchus
    • Inferior lingular segment bronchus
  • The secondary carina separating the lingular division from the left lower lobe bronchus is called Left Carina-2 or LC-2 (Fig. 32).
 
Left Lower Lobe Bronchus
  • The left lower lobe bronchus (Fig. 32) is slightly longer than right lower lobe bronchus by about 1 cm
  • The left lower lobe bronchus divides into its four segments:
    • Superior segment bronchus
    • Anterior basal segment bronchus
    • Lateral basal segment bronchus
    • Posterior basal segment bronchus
  • The left lower lobe initially gives rise to the superior segment bronchus, which is posteriorly located separately and at a greater distance from the its basal divisions (Fig. 36)
  • The three basal pyramid bronchi called left anterior basal, left lateral basal, and left posterior basal segment bronchi are in mirror shape compared to those on the right (Fig. 37)
  • The left medial basal segmental bronchus is usually but not always absent.
 
NOMENCLATURE OF AIRWAYS
Jackson-Huber classification is most commonly used that describes and names the divisions in accordance with the anatomic space orientation.1 Yamashita Japanese classification classifies bronchial tree with numerical nomenclature,14 which assigns numbers to the segmental airways (Table 1). The other less popular classification is Boyden's,15 which is more for surgical purposes. This classification also divides bronchial tree numerically. The Boyden surgical anatomy refers to the anterior and posterior segments of the upper lobe as B2 and B3. This nomenclature is usually not used by bronchoscopists, who prefer the Japanese System using anterior as B3 and posterior as B2. However, the Jackson-Huber classification is most widely used and less complex.13
Table 1   Nomenclature of airways
Right bronchial tree
Left bronchial tree
Jackson-Huber nomenclature
Japanese Yamashita classification
Jackson-Huber nomenclature
Japanese Yamashita classification
Right upper lobe
Left upper lobe
Apical
B1
Upper division
Anterior
B3
Apicoposterior
B12
Posterior
B2
Anterior
B3
Right middle lobe
Lingular division
Lateral
B4
Superior
B4
Medial
B5
Inferior
B5
Right lower lobe
Left lower lobe
Superior
B6
Superior
B6
Medial basal
B7
Anterior
B8
Anterior basal
B8
Lateral
B9
Lateral basal
B9
Posterior
Posterior basal
 
CONCLUSION
The anatomy of respiratory tract is complex and includes both upper and lower airways. It is not something just to get past in order to do the bronchoscopy. The spatial orientation of the airways is key to recognition of various anatomical structures in the airways. A proper understanding of airway anatomy is necessary for one to become an expert bronchoscopist. This will aid in performing specialized diagnostic and therapeutic bronchoscopic procedures.
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