Defects in the Development of the Respiratory System (Easy to Understand)

Anomalies in the development of the lungs explained in 10 minutes.

If you are completely new to embryology and you want to understand it quickly, this should be the first video you watch:
   • Introduction to Embryology - Fertilis...  

Normal lung development (Easy to Understand):
   • Embryology of the Lungs (Easy to Unde...  

0:00 Brief Introduction to Embryology
1:53 Message from Sponsor
3:12 Respiratory Development
5:29 Tracheoesophageal fistula and oesophageal atresia
8:08 Respiratory Distress Syndrome

--------------------------------------------
MESSAGE FROM SPONSOR
--------------------------------------------
Many thanks to BNX for sponsoring this video. BNX makes high-quality American made N95 masks/respirators. I wore them instead of the usual N95 masks I am required to wear and found them considerably more comfortable than the hospital grade masks that provide the same protection. They are lightweight, comfortable, and lint-free. Use the links below to check it out, and don't forget to use the code L5YCZTEC for a discount: https://bnx.com/made-in-usa/n95-mask-...

Product links:
BN-N95-H95B-10PP - https://amzn.to/3PDBmDs
BN-N95-H95W-10PP - https://amzn.to/3PJspIW
BN-N95-F95W-10PP - https://amzn.to/3wOI2WL
BN-N95-F95B-10PP - https://amzn.to/3GeC7yi
BN-KN95-E95-BLACK-20PP - https://amzn.to/3a98ORS
BN-KN95-E95-WHITE-20PP - https://amzn.to/3wJqNpD
BN-N95-H95B-10PP - https://amzn.to/3PDBmDs
BN-N95-H95W-10PP - https://amzn.to/3PJspIW
BN-N95-F95W-10PP - https://amzn.to/3wOI2WL
BN-N95-F95B-10PP - https://amzn.to/3GeC7yi
BN-KN95-E95-BLACK-20PP - https://amzn.to/3a98ORS
BN-KN95-E95-WHITE-20PP - https://amzn.to/3wJqNpD

--------------------------------
Recommended Text
--------------------------------
Easy Embryology is a book that is dedicated to the simplification of embryology. It is available at https://drminass.com/product/easyembr.... Contact Dr. Minass for more information.

----------------------------------------
Interact With Dr. Minass!
----------------------------------------
Website - https://www.drminass.com
Email - [email protected]
Patreon -   / drminass  
Facebook -   / m1na55  
Instagram - @m1.nass
Post - Address to:
Minass
Parcel Locker 10106 04448
59 Penshurst Street
Willoughby, NSW
Australia 2068

Summary for your notes (this video):
Abnormalities in partitioning of the esophagus and trachea result in oesophageal atresia with/out tracheoesophageal fistulas (TEF).
There are various types, most frequent of which occurs with the upper portion of the oesophagus ending in a blind pouch and the lower end forming a fistula with the trachea.
Respiratory distress syndrome (hyaline membrane disease) occurs when there is insufficient surfactant in the newborn lungs causing collapse of the lungs on expiration
Ectopic lung lobes can also arise from the trachea or oedsophagus
Congenital cysts of the lung may also occur from dilatation of bronchi (not mentioned in the video but important to note)

Summary for your notes (normal lung development):
Formation of the lung buds: at 4 weeks of gestation, the respiratory diverticulum (lung bud) appears as an outgrowth from the ventral foregut. Retinoic acid from surrounding mesoderm is the initiating factor (as it causes up-regulation of transcription factor TBX4) - not spoken about in video to keep things simple.
Epithelium of the lung is derived from foregut.
Connective tissue, muscle, and cartilage is from splanchnic mesoderm.
Parietal pleura is from somatic mesoderm; and visceral pleura is from splanchnic mesoderm.
Tracheoesophageal ridges separate the lung bud from the foregut, and fuse to form a tracheoesophageal septum.
Lung buds form bronchial buds which form into the right and left main bronchi.
Growth is caudal and lateral to fill the pericardioperitoneal canals.
10 tertiary bronchi (segmental) are developed on the right, and 8 in the left. These correspond to the bronchopulmonary segments in an adult lung.
Terminal bronchioles divide to form respiratory bronchioles and these divide into alveolar ducts.
The terminal sacs are initially cuboidal epithelium but the distal portion become squamous as the vascular supply grows near it - these are the Type 1 alveoli.
Type 2 produce surfactant.

Congenital abnormalities:
Esophageal atresia: abnormalities in partitioning of the oesophagus and trachea. Fistulas may also persist
The three types spoken about in the video make up the most common types.
The proximal blind ended esophagus, and a tracheoesophageal fistula to the distal part of the esopahgus is the most common type (90%).
There are two other types which are much rarer (1% each) so it wasn't spoken about in the video. They include: (1) a proximal fistula, and a distal blind-ended esophagus, and (2) a fistula to the trachea from the esophagus both distally and proximally.