1. Ventilation – mov’t of O2 in & CO2 out of the alveoli.

2. Ex∆ of gases across the alv – cap membrane (O2 to pul cap & CO2 t o alv).

3. Transport of gases in the blood.

4. Ex∆ of gases at the tissue level.

Alv are considered gas ex∆ areas & everything above the alv are ventilated only.

Pul artery carried de O2 blood back to the cap which encloses the alv & hbg becomes O2, the pul vein carries O2 Hgb to the L.A. & then pumps it out to the rest of the body.

Lymph sys is imp with ARDS B/c it cleans up excess debris & fluid in the interstitial spaces.

CHF there is a back up of blood & fluid into the pul vein ↑P in the pulvein so fluid travels into interstitial spaces, usually the lymph system carries it away, but it becomes too much, seeping into alv causing pul edema.

VT =amt of air exhaled after a N inhal N= 7-9 cc/kg

Ie. 70 kg man (7-9 cc/kg ) = 490-630 cc

This calc N tidal vol, but problems arise when vent is obs, pt must ↑RR to move same vol = min vent.

Increase WOB, increase E to main vol they decrease VT & increase freq

Ext intercoastals: pull ribs out & up

Ie. VE= VT(RR) VT= 500 RR=15 VE =500x15= 7500 7.5 L/min

Some topics in this essay:
Ie VT=, Boyle’s Law, R/L Plural, O2 CO2, H2O H2O, AIRWAY Factors, Volume VT, ARDS B/c, Dead Space, WOB Accessory, increase wob, pul edema, surface tension, dead space, decrease comp, = decreased, overcome resistance, lung expansion, resistance lung expansion, chest wall, lung b/c, decrease comp 3, lung expansion compliance, tension decrease comp, surface tension decrease,