left main bronchus

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left main bron·chus

[TA] Avoid the incorrect term left main stem (or mainstem) bronchus.
primary division of the tracheobronchial tree arising as the left branch of the bifurcation of the trachea, then passing in front of the esophagus and enters the hilum of the left lung where it divides into a superior lobe bronchus and an inferior lobe bronchus. It is longer, of narrower caliber, and more nearly horizontal than the right main bronchus, hence, aspirated objects enter it less frequently.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Foreign bodies were located in the left main bronchus in 8 (22.2%) patients, the right main bronchus in 19 (52.8%), the right distal bronchi in 2 (5.5%), and in the left distal bronchi in 1 (2.8%) patient.
Foreign bodies get lodged in any of the three narrow points in the oesophagus: the cricopharyngeal area, the middle third of the oesophagus where the aortic arch and left main bronchus cross the oesophagus or the lower oesophageal sphincter.
The left main bronchus is approximately 5cm long where it bifurcates into left upper and lower lobe bronchus.
Secondly surgery requiring full carinal resection and reconstruction, cross-field ventilation as described above and the cross-field tube is inserted into the left main bronchus after the carina is resected.
Bronchoscopy revealed white-yellowish exudate covering the whole left main bronchus and narrowing the lumen (Figure 1, panel H).
The stenosis sites were divided into 5 locations: (I) trachea, (II) left main bronchus, (III) right main bronchus, (IV) right middle bronchus, and (V) lobe bronchus.
Investigations showed bronchomalacia of left main bronchus. Echocardiography showed ASD II, which was closed surgically at 6 months of age.
[14] reviewed over 1,000 pediatric cases of foreign body aspiration and reported that the bronchoscopically detected lodgment sites included the larynx (3%), trachea (13%), right main bronchus or distal branch (60%), and left main bronchus or distal branch (23%).
Bronchoscopy revealed a large mucous plug completely occluding the left main bronchus. It was necessary to remove the plug.
On flexible bronchoscopy examination of her lower airways, no foreign body was seen, but significant external nonpulsatile compression over the left main bronchus was noticed; the rest of the airway anatomy was normal.
In the left main bronchus, there were scarce and diffuse mucohemorrhagic secretions in the bronchial tree, predominating in the bronchus for the upper left lobe, with no evidence of apparent active bleeding.
Left main bronchus is smaller in size and a bit angulated, thus making it easy for a foreign body to enter right main bronchus.