Ventilation
The process of moving gas (usually air) in and out of the lungs
Ventilation
(P1V1 = P2V2) As lung volume increases, intra-alveolar pressure drops below atmospheric pressure (to about -1 mmHg, or 759 mmHg)
Boyle's Law
Dead space for a patient on 40%, PaO2 80, and 150 lb of ideal body weight
1 mL/ 1 lb= 150 mL
3. Barriers to diffusion
A/C membrane has three main barriers
1.Alveolar structure (scarred)
2.Interstitial space (fluid)
3. Capillary structure (thickness
Relationship between PaO2 and SaO2 is S-shaped refers to
HbO2 dissociation curve
refers to the physiologic processes of oxygen use at the cellular level.
Respiration
Lungs distend easily (hyperinflate) but poor recoil
Compliance
VT 800, RR 8, 180 lbs, PaO2 92, SpO2 95%. Calculate the alveolar ventilation
(800 - 180) = 620 * 8 = 4.960 L
Normal PA -PaO2 is normally
PaO2 5-10 mm Hg less than PAO2
Normal Total oxygen content of blood
is 16-20 ml/dl
Volume measured during either inspiration or expiration
Tidal volume
4 Factors Contributing to Work of Breathing
1.Compliance
2.Resistance
3.Active Exhalation
4.Ventilatory Pattern
PaO2 80, PaCO2 40, FiO2 21%. Calculate the alveolar air equation
PAO2 = ((760 – 47)0.21 – (40/0.8)
713 x 0.21 = 150 – 50 = 100 PAO2
Each gram of Hb can bind _____ of oxygen.
1.34 ml
DO2 is normal, but cells undergo hypoxia
Dysoxia