Lecture 18 4/8/14 Flashcards
Is breathing a active or passive process?
Active Process
Relaxing on Expiration is what type of process?
Passive Process
Decrease in surface area decreases what?
Gas Exchange
Tracheal Rings
Trachea is lined with approx. 20 tracheal ringed cartilages
Anatomy of Trachea
C shaped circulation. The esophagus expands when we swallow. Opened in the back, as it expands the esophagus during swallowing.
Trachealis Muscle
A muscle that goes across the back of the Trachea. The muscle will contract on forceful inspiration to help keep the trachea opened.
Why do we need the tracheal rings?
Or Portion of Cartilage Rings? To provide structure and prevent collapse on inspiration. The reason why is because when you’re sucking it is causing negative pressure. Prevent the collapse of walls during inspiration.
Right and Left Main Bronchi
The bifurcation is located at the T5 vertebral level. Like the tracheal rings, the primary bronchi contain incomplete rings lined by ciliated columnar epithelium.
Transition from Cartilage to No Cartilage Description
The bronchials and terminal bronchials, and respiratory bronchials, the trachial rings are not there because the collapsing force is not as strong as those in the Trachial rings. We transition from cartilage to smooth muscle from the segmented bronchi to the bronchioles because the collapsing pressure is non-existent at this level.
8 Levels of Bronchial Tree
a) R and L Main Bronchi
b) Secondary or Lobar Bronchi –
c) Tertiary or Segmental Bronchi –
d) Bronchioles
e) Terminal Bronchioles
f) Respiratory Bronchioles
g) Alveolar Ducts
h) Alveoli
Alveoli
About 300 million of these and significant (7 Tennis Courts) surface area for gas exchange about 70 square meters. Look like Cup shape out pouchings. Look like grape like cluster. Is where gas exchange occurs between air and the blood.
Cell Types of Alveoli
- Simple Squamous Epithelium
2. Septal Cells
Simple Squamous Epithelium
One cell layer thick, flat, allows for easy gas exchange across the membrane.
Septal Cells
Known as Type 2 surfactant cells. Because they lay in the septa.
Septal Cells Produce What?
Produce surfactant (phospholipids) which reduces the surface tension between the alveoli.
Surfactant Cells in babies are What?
Surfactant cells are the immature cells with premature babies, the babies having to go to oxygen tents and give them growth factors to accelerate the growth of these cells
Surfactant Cells Help babies with What?
To help babies mature more quickly because if you don’t have Type II Surfactant cells, that decreases the surface tension within the alveoli and it makes it much harder for these babies to breath.
Surfactant cells reduce surface tension between what?
Surfactant cells reduce surface tension between water molecules so that the Alveoli can be opened to get air back into the lungs.
Describe the lobes of the lungs
3 Lobes on the right and 2 Lobes on the left on the lungs.
Right Lungs
Divided into Superior, Middle, and Inferior Lobes.
Horizontal Fissure of Right Lung
Separates Superior from Middle lobes
Oblique Fissure of Right Lung
Separates Middle from Inferior lobes
Left Lung
Divided into Superior and Inferior Lobes
Oblique Fissure of Left Lung
Separates superior and inferior lobes.
Lungs
Main Organ of Respiration
Surface Anatomy of Lungs
Parietal Pleura
Visceral Pleura
Parietal Pleura
Is the Serrous membrane that adheres to the inside of the thoracic cage.
Visceral Pleura
Is going to adhere to the outside of the lungs.
Laws Associated with Respiration
External Respiration
Internal Respiration
External Respiration
Gas exchange between the outside air and the blood at the lungs.
Internal Respiration
Gas exchange between the blood in the cells and the tissues.
Profusion of the tissues
Ventilation
AKA Breathing; process by which atmospheric gases travel into the lungs and waste gases travel outside of the lungs.
Alveolar Ventilation
movement of air in and out of the alveoli. Not an active process, it’s diffusion.
Inspiration
AKA Inhalation – process by which air enters the lungs.
Is an active process.
Contraction of the diaphragm, pulling it downward, creating a vacuum and pulling air into the lungs.
Negative pressure, creating a vacuum.
External Intercostals
Run obliquely; attach to the rib up above and below. Pulls the rib upward to increase thoracic cage diameter.
Muscles involved with Inspiration
Diaphragm
External Intercostals Muscles
Intrapulmonic Pressure
Intra means within. So it’s pressure measured across the lungs into the alveoli. This is the lesser of the two pressures.
Interpleural Pressure
Inter means between. So it’s pressure measured in between the pleural membranes. This is the greater of the two pressures. Because it has to be great enough to pull the alveoli closer to the lungs.
Which is the greater pressure between Interpleural Pressure or Intrapulmonic Pressure
The intrapulmonic pressure is significantly less than interpleural pressure but great enough to open the alveoli.
Expiration
AKA Exhalation - process by which air leaves the lungs. Is a passive process. Inspiratory muscles - they are relaxing
Muscles involved for normal expiration
Diaphragm
External Intercostals
Forced Expiration
what actually contracts. Have to exhale quickly to increase our rate of gas exchange
Muscled involved for forced expiration
Internal Intercostals - it pulls the ribs downward
Abdominal obliques - they will contract and pull ribs downward also
Rectus Abdominus
Respiratory Law
Boyle’s Law
Boyle’s Law
Is the reason why respiration works, the inspiration and expiration.
System is inversely proportional to pressure; V = 1/P
Decrease the pressure we are increasing the volume.
Pressure differences inside the lung, relative to constant atmospheric pressure, causes air to move in and out of the lungs.
Respiratory Emergencies
Pneumothorax
Decreased Surfactant Production
Pneumothorax
We’ve got air in the pleural cavities
Abnormal collection of air or gas in the pleural space that separates the lung from the chest wall and which may interfere with normal breathing.
