Conductiing Zone

No gas exchange

Has its own blood vessels

Increaseing dead zone increases what?

you increase the degree in which no gas exchange

The percentage of oxygen that is distributed

through the body is affected by ?

The conducting zones blood vessels

Concha /Turbinators  

Create air turbulence

filters out heavy particulates

Have blood vessels, swelling bodiesthat alternate vasodilating & vasoconstriction (very vascular)

adds (100%) humidity and warm air to body temperature

The swelling bodies add?

100% humdity 

brings inspired air to body temp

Gas exchange is based on what?

Percentages not numbers

Larynx

• Cartilaginous

• Glottis(the hole) covered by the Epiglottis (flap)

• During swallowing larynx lifts up and epiglottis closes

• Attached to hyoid bone

soft palate does the same thing the epiglottis

does, but for the nasal cavity

Soft palate goes up and closes of the nasal passages vs. epiglottis closing off the airway.  

Dichotomous branching

• Each bronchi split into 2 and each of those terminal ends split into 2, and repeats through the bronchioles (systematically splitting/ dividing by two.

The terminal bronchiols signifies what?

The conducting zone ends

cartilaginous rings

design and purpose

They’re “C” shaped, but the “C” is crooked to have more diameter change that increases the amount of bronchodilating/ bronchoconstricting.

• During Inspiration a vacuum sucking force is being created.  The cartilaginous rings prevents everything from collapsing

• allow for bronchodilation/ bronchoconstriction

Ciliated Pseudo

stratified Columnar Epithelial

Has basement membrane

Made of Columnar cells in one layer

“baby” columnar cell (refer to pic) isn’t mature enough to reach lumen surface so it appears as a 2nd layer, but it’s not.

every cell touches the basement membrane

Goblet cells

muco-ciliary escalator

• sits on surface of the Pseudo stratified Columnar Epithelial.

• 
  

• It will be swallowed down and digested away.

• roundworms utilize the muco-ciliary escalator as part of their reproductive cycle

Cystic Fibrosis (CF)

Mucus related disease

chloride channels that have CFTR (Cystic fibrosis trans membrane regulator) which are regulated by cAMP (Cyclic AMP)

If you have insufficient chloride channels or defective CFTR than chloride won’t move and H20 in the airways wont’ move

If CFTR is knocked out, mucous is still produced, but it’s thick. It gets clumpy and doesn’t move = air trapping, collapse of small airways

gas exchange still occurs

become sticky and act like agar creating a nutrient broth of protein and mucous

acts as a reservoir to grow and feed bacteria that get trapped in the mucous

Pancreatic enzymes

Chest PT

Humidification 

What do the ciliated pseudo stratified columnar epithelial cells change into in the respirtory zone

 simple squamous 

There are chloride channels that have CFTR (Cystic fibrosis trans membrane regulator)

What is it regulated by?

cAMP (Cyclic AMP)

need to be thin for diffusion

Alveolar sacs

have

Type 1 pneumocytes (simple squamous epithelial cells)

and 

Type 2 pneumocytes (interspersed amongst the type 1)

interspersed amongst the type 1

release surfactant

What is surfactent and what does it do?

a phospholipid.

Breaks some of the hydrogen bonds between the H20 molecules and intermingle with the H20 and reduce surface tension.

What happens in Adult Respiratory Syndrome?

damage has been done to the deep lung and killed of Type 2 pneumocytes > no surfactant > collapse of alveolar sacs with every exhalation

How much pressure is needed for a baby to initially inflate the lungs

60-70mmHg

Alveolar Macrophages (immune system)

crawl around the surface of the resp. system

Alveolar macrophages don’t leave the lungs. When they fill up they die and other macrophage eat them. They clean junk up and keep it within like a garbage bag.

Alveolar macrophages don’t leave the lungs. When they fill up they die and other macrophage eat them. They clean junk up and keep it within like a garbage bag.

Apex

Right behind the collar bone @ cupola

No muscle guarding apex.

There’s tough connective tissue

Visceral pleura

the pleua next to the lung

Parietal pleura

does not touch the lung, its next to the rib cage

Pleural space

In the middle of parietal and visceral layers

Not really isn’t a space.  

Has serous fluid that’s watery, cohesive, and adhesive.  

The serous fluid glues the visceral pleura to the parietal pleura. Your lungs are glued to the thoracic cavity by H20.

Elastin elastic

surface tension

physiology atmospheric pressure 

and

Alveolar Pressure (alveolar space is an open system)

alveolar pressure goes from

+1 to a -1cmH20

pleural pressure goes from

-5 to -8 cmH20

Max lung volume

4.5L - 5L

Tidal volume

500 ml

All diaphragm

No ribs

The max amount of air you can take in from end expiration 

inspiratory capacity

If you get rid of your tidal volume while inspiring

inspiratory reserve

your capacity is how much you can go from the troph to the peak to breathe in

When you subtract out the tidal volume

maximum volume of air that can be exhaled following a deep inspiration

Vital capacity 

 the volume of air that remains in the lungs during quite breathing

Functional Residual Capacity (FRC) 

or the amount of air left in the lung after quite expiration

Forced expiratory volume

FEV

measures how much air a person can exhale during a forced breath

FEV1

Amount of air expired in 1 second

Should be 80%

What if FEV1 is low (<.80)?

COPD

Residaul volume

volume of air still remaining in the lungs after the most forcible expiration possible

prevents lungs from collapsing, It represents stale air

If Vt is 500 how much goes to lungs and how much stays in conducting zone?

350 ml to resp. zone

150 ml stays in conducting zone

How many breathes does it take to completely saturate and fill the lungs?

12 breathes

Right atrium pressure

Right ventricle pressure

RA pressure 0

RV pressure 25

Pulmonary artery pressure

25/8

mean 15

Pulmonary artery

called pulmonary trunk

thinner than aorta

thicker than IVC

about 5cm long

same amount of blood ejected into aorta is eject into PA

so PA has to be very complient 

volume of PA, pulmonary cappillary, and pulmonary vein

PA 190

Pul. capp 70 ml

Pul. vein 190ml

describe pulmonary cappillaries?

low volume, high surface area

NO bulk flow (very little interstitial tissue)

thin basement membrane between the endothelium and type 1 pneumocyte

distance between 2 cells

1/10 of a micron = very short distance

Blood oncotic pressure, up, down, or same?

why?

stays the same b/c blood has protein

Blood hydrostatic pressure increase, decrease, or same?

decreases

b/c of the shorter distance and lower pressure

            systemic                                pulm. system

BO               --                                      --

BH               --                                      --

TO               --                                      --

TH               --                                      --

pulmonry lympatics BH+TO+TH = 29

systemic                                pulm. system

BO             28                                           28

BH            17.3                                          7

TO              8                                            14

TH             -3                                           -8

pulmonry lympatics BH+TO+TH = 39

what is the purpose of the lymphatics system in the lung

Acts like a shop-vac, always on

++keeps lungs dry (moist)

systemic lo O2 and hi CO2 =

pulmonary  lo O2 and hi CO2 =

systemic

you increase metabolism and vasodilate

Pulmonary lobe

vasoconstrict (you don't want to send blood to a lobe with poor gas exhange)

magic number 70 

below blood shunted away 

above blood shunted to that lobe

what happens in

chronic bronchitis?

pneumonia?

all the ateriols are vasoconstricted due to systemic Po2 less than 70 which causes the heart to work harder

Right heart failure

effected lobe vasoconstrited to shunt blood better perfused areas

Left atrium pressure

2 - 3 mmHg

can handle pressure up 5mmHg

Once pressure gets around 6 - 7 mmHg what happens?

back pressure into the pulmonary vein and venules

(causes them to expand/dilate)

once it backs up to the pulm arteriols then they expand causes greater distances between = decreased surface area

causes the right side of heart to work harder can compensate up to 40 - 50 mmHg

(double the pressure head)

pulmonary edema 

right sided heart failure

Disease processes on the left side of the heart that cause right sided heart failure

AV valve regurgitation or stenosis

Regurg. blood pushes back in the wrong direction

        ++worse b/c lung fills very quick

Stenosis valve fails to open = back pressure

        ++ lung fills slow

Conducting zone blood flow

 only venous blood goes threw lungs

segments of the aorta supplies blood to the conducting zone

veins drain conducting system and puts it back into the pulmonary vein 1-2% mixed into LA

(SpO2 is 95-97%, not 100%)

What is the gravitational forces exerted on the top and bottom of the lungs in mmHg?

-15mmHg at the top

8mmHg at the bottom of the lung

gravitational forces exerting pressure on the body creates pooling

describe zone 1

top of the lung, small space above the heart

Considered physiologic dead space

pressure in this zone is -15

zone II

At the level of the heart (so difference is sys. and dia)

pressure in RV is 25 during systole - gravity force(15)

25 - 15 = 10mmHg

during diastole RV pressure is 8

8 - 15 = -7

what is special about blood flow in Zone II?

You only have blood flow during systole b/c you need enough pressure to over come gravtational force

Diastole doesn't exert enough pressure to overcome gravity

Zone III

Zone III is below the heart

systole 

RV 25 + 8(GF) = 33

Diastole

RV 8  + 8(GF) = 16

describe Zone III's pressure in regards to systolic vs. diastolic

both are positive so both exert enough force to overcome gravity

Zone I 

ventilation > perfusion

(over-ventilated, under-perfused)

Zone 3

ventilation < perfusion

(under-ventilated, over-perfused)

What does this mean in regards to V/Q

This is why our V/Q doesn't = 1

The weight of air on you at sea level is?

760 mmHg

partial pressure of O2 and %?

CO2?

pO2 160 mmHG

21%

CO2 is so low we consider it 0

(.3mmHg or .03%)

On the ppO2 vs ppCO2 describe V/Q at the top of the graph (Zone 3) and at the bottom of the graph (Zone 1)?

represents shunts

Zone III Ø/Q = 0

Zone 1 V/Ø = infinity 

mmHG at sealevel

% O2

ppO2

ppCO2

760 mmHg

21%

ppO2 160mmHg

ppCO2 0.3mmHg

Remember diffusion goes form 

hi to lo

Formula

Diffusion

Δpressure X area x solubility

-----------------------------------------------

distance X (square root of) Mol wgt

= diffusion coefficient

Diffusion coefficient formula

solubility ÷ √ molecular weight

What is diffusion coef. of oxygen?

CO2?

ppO2 = 160 = 1 (diffusion coefficient)

ppCO2 = 0.3 = 20.3 (diffusion coefficient)

CO2 diffuses 20 times faster than oxygen

Pulmonary system distance

0.2 - 0.6

RBC   pulmonary    basement     type 1            Alveolar

        endothelium  membrane   pneumocyte    air

Tiny distance 0.2-0.6 microns

1 RBC is 10 microns

Diffusion rates systemic vs pulmonary

Systemic = diffusion slower

Pulmonary = diffusion faster

Capacity vs. Reserve

Wht includes Vt and what doesn't

Capacity includes Vt

Reserve exclude Vt

(lots of reserve, and is old stale air)

How many breathes does it take to replace the air in your lungs?

12 breathes to completely replace all the stale air

or 

17 seconds