Lung Physiology 1 and 2 Flashcards
Structures which contribute to respiratory pump?
1) Bones (Ribs and sternum)
2) Muscles (Diaphragm and IC’s)
3) Pleura
4) Nerves
What nerves are the diaphragm innervated by?
C3,4,5
Define dead space?
Where air is supplied, but no GE occurs
What does ventilation allow for?
Bulk flow in airways
1) O2/CO2 movement
What is perfusion and specific to lungs?
1) Blood supply
2) Pulmonary blood supply i.e. P arteries
What is a V/Q mismatch?
Perfusion of blood in capillaries doesn’t match alveoli ventilation
What is Pulmonary capillary perfusion dependent on? (3)
1) Alveolar pressure
2) PA pressure
3) PV pressure
What is hypoxic pulmonary constriction?
Constriction of vasculature, means O2 not delivered to dependent points in lungs
Distinguish differences in Respiratory Nomenclature (4)
1) Pa is arterial pressure
2) PA is alveolar pressure
3) Pi is inspired pressure
4) v̇ w/ (A= Alv vent) [CO2 is CO2 prod]
What causes ODC shift to right and meaning?
1) Increase in Temp, decrease in pH
2) Increased o2 dissociation, so affinity decreased
What are 7 layers for gas exchange?
1) Alveolar Epithelium
2) Interstitial Fluid
3) Capillary Endothelium
4) Plasma Layer
5) RBC Membrane
6) RBC Cytoplasm
7) HB Binding sites
What is the alveolar gas equation?
PAO2 = PiO2 - (PaCO2/R)
Enzyme catalysing formation of HCO3- and H+ from CO2 and H2O?
Carbonic Anhydrase
What is the acid/base dissociation equation?
CO2 + H2O = H2CO3 = HCO3- + H+
Name the HH equation
pH= pKA + log (A-)/(HA)
What causes respiratory acidosis and alkalosis?
1) Ac: Inadequate ventilation
2) Alk: Hyperventilating due to Hypoxia
Renal compensation mechanism for R acidosis/alkalosis?
1) ^NH3 formed, H+^ secretion, so more HCO3- reabsorbed
2) H+V sec, so more H+ retained, less HCO3- reabsorbed
What causes metabolic acidosis and alkalosis?
1) Ac: Renal failure (VHCO3-, XS H+ prod)
2) Al: Vomiting (Loss of H+)
Respiratory compensation for each metabolic?
1) CR stim, enhance resp, PaCO2 V
2) CR inhib, V insp, PaCO2 ^
Define FVC
Max vol of air forcibly exhaled after max in
Define FEV1
Max forced vol of air in 1 second
Define TLC and how calculate?
1) Full capacity of lungs
2) Vital capacity + Residual volume
Define Peak flow
Greatest rate of airflow that can be obtained during forced exhalation
What is lung compliance?
Measure of lungs ability to stretch and expand
Compliance = ∆V/∆P.
What is DLCO?
Uptake of CO in ml at standard T and Pa
Why is CO used to estimate DLCO?
High affinity to bind to HB
What does DLCO show?
Ability of lung to transfer gas into blood stream from inhaled air
