Premature Infants: Underdeveloped Lungs at Birth

The mechanism ?

Surfactant air interface deficiency in premature babies

now an embryo's alveoli has a fluid -air interface
I mean the fluid lining the alveoli is in contact with the air entering

late in fetal life , Cortisone and Thyroxine stimulate surfactant formation that will form a surfactant -air interface
I mean now surfactant ( lipoprotein ) seperates between fluid and air

a premature baby doesnt have surfactant
How can this harm him ?

Laplace law ( P ) = 2T/r

I mean the more u decrease the radius of the alveoli ( r ) the more u increase the pressure ( P ) so this will contract the alveoli
weither the contraction degree leads to collapse or not this is the difference

In fluid air interface

The surface tension ( force of atraction between molecules ) is higher than surfactant air interface , so this will contract the alveoli till it ( collapse ) leading to air movement according to concentration gradient from b ( lower pressure )to a(higher pressure )

In surfactant air interface
Surfactant surface tension is 10 times less than fluid ( since its lipoprotein ) so it prevents the collapse of alveoli keeping it patent during expiration especially which facilitates respiration Since surface area for air exchange will be more

So in premature decreased lung volume is due to decreased surface area for gas exchange due to alveoli collapse caused by fluid air interface

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Now this thickness is caused by increased filtration of fluid from the pulmonary vessel to the interstitium = pulomary edema

Mechanism ?

To keep the lung dry allah created pulmonary vessel ( 10 mmHg ) with Hydrostatic pressure less than systemic ( 35 mmHg )so that fluid keeps flowing from interstitum ( higher pressure ) to the pulmonary vessel ( lower pressure )

If the alveoli contracts in premature infant it will increase the width of interstitium that lies between it and the blood vessel decreasing the interstitium pressure in contrast to alveolar pressure that rises

This will causereversal of fluid flow from vessel to interstitium = pulmonary edema

Conclusion

This process and these 3 points up is affected in a premature infant due to : surfactant air interface deficiency

Great Job
Thanks !

here's a rush mistake but no need for correction easy to comprehend it

i apologize i make lots of rush mistakes

addition :
Hyaline membrane disease; Infant respiratory distress syndrome (IRDS
on clinical examination lack of surfactant will put the infant in an episode of tachypnea or even apnea to compensate for the less gas exchange . Infants may also appear cyanotic

The lungs have a characteristic "ground glass" appearance, which often develops 6 to 12 hours after birth

Note diffuse granularity of the lungs and air bronchograms.

It is the most common cause of respiratory failure in newborn infants.

it is produced by type 2 pneumocytes
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conventional therapy for the affected infant includes :
respiratory support with oxygen
continuous positive airway pressure
mechanical ventilation
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artificial surfactant improve RDS
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chronic lung disease is a long-term complication of RDS
why ?do you know?

a thoery of mine :

since the treatment is mainly oxygen this can put the infant at risk of oxygen toxicity-one of which is retinopathy-- blindness .
Air also might escape to the surrounding spaces ( pneumothorax - pneumomedianum -pneumopericardium )

or maybe the oxygen lack in case of normal RDS progress will affect all organs -including lung- during periods of hypoventilation to brain , lung , heart , for ex.

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continuous positive airway pressure (CPAP)that delivers slightly pressurized air through the nose can help keep the airways open
Extracorporeal membrane oxygenation (ECMO) to directly put oxygen in the blood if a breathing machine can't be used
Inhaled nitric oxide to improve oxygen levels

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incredible you are genious

am not a genious , am just a hard worker with much of a mother's blessings

and if i had the key , the MOST EFFECTIVE for any success door is quran , the more u read per day the more u open doors

am not talking from an islamic vision , am talking from a trial vision