Pathophys quiz 2 Pulmonary Flashcards
Ventilation
exchange of air between the atmosphere and alveoli (difference in pressure if created by respiratory muscles)
Flow=
Change in pressure / resistance
Flow is greatest if the difference in gas pressure is _____ and resistance is ______
high, low
Boyles law
At constant temperature, the pressure of a gas varies inversely with its volume
P1V1=P2V2
If pressure in the lungs goes down, volume goes______ and if pressure in the lungs goes up, volume goes ______
up , down
Inspiration
Palv < Patm
Expiration
Palv > Patm
for every ___ units of O2 you intake, you expel ____ units of CO2
10, 8
Palv when exhaling
positive (creates pressure to force air out)
Palv when inhaling is
negative
Palv at the end of both inhaling and exhaling is
0, no air movement
Alveolar ventilation
total volume of fresh air entering the alveoli per minute
Tidal Volume
Total amount of air that we inhale and exhale
Inspiratory reserve volume
the extra air we can breath in past normal breathing
expiratory reserve volume
the extra air we can breath out past normal breathing
residual volume
the air we can not breath out (why the Heimlich maneuver works)
at what % of saturated hemoglobin do you have to breath?
65%
How do low temps affect how Hb holds onto O2?
- Metabolism slows so O2 demand is less
- Hb holds onto O2 tighter
How do high temps affect how Hb holds onto O2? (fever)
Hb drops off O2 faster
How do high pH affect how Hb holds onto O2?
Hb holds onto O2 tighter
How does low pH affect how Hb holds onto O2?
Hb lets go of O2 easier
How does high 2, 3 DPG (produced by glycolysis) affect how Hb holds onto O2?
Hb lets go of O2 easier
How do low 2, 3 DPG (produced by glycolysis) affect how Hb holds onto O2?
Holds onto O2 tighter
Hypoxemia
lack of oxygen in the blood
Hypoxemic hypoxia
reduced arterial O2 (can be caused by lack of oxygenated air, pulmonary problems, lack of ventilation-perfusion coupling)
Hypoxia
inadequate oxygen delivery to tissues
4 causes of hypoxia
- Anemic
- ischemic
- histotoxic
- hypoxemic
Anemic Hypoxia
poor O2 delivery because of too few RBC’s or abnormal hemoglobin
Ischemic Hypoxia
Blood circulation is impaired
Histotoxia hypoxia
the body’s mitochondria are unable to use O2 (cyanide causes this)
Hypoxemic hypoxia
reduced arterial O2 (can be caused by lack of oxygenated air, pulmonary problems, lack of ventilation-perfusion coupling)
you can have _____ without ______ but if you have ______ you WILL have______
hypoxia without hypoxemia
hypoxemia you will have hypoxia
in what zone does gas exchange happen?
respiratory zone
what makes up the respiratory zone?
alveoli
what makes up the conducting zone?
everything besides alveoli
Conducting zone:
low-resistance airflow, defense against foreign material / infection, warm the air
what 2 things make up the trachea?
cilia and goblet cell
Goblet cell produce what?
mucous
what does smoking kill?
cilia (when they grow back ex smokers develop a cough
alveolar cells are responsible for what?
gas exchange
Type I alveolar cells are also called what?
pneumocytes
what do type II alveolar cells produce?
surfactant
why is the bronchus covered in smooth muscle?
to direct air flow
3 types of relexes
Foreign body reaction
Voluntary control of breathing
J receptors
Foreign body reaction
coughing and sneezing
Voluntary control of breathing
holding your breath or rapid breathing
J receptors
- in lung tissue, innervated by the vague nerve
- stimulated by fluid buildup in lungs interstitial space (embolism, pulmonary edema, exercising extremely hard)
- results in: dyspnea, rapid breathing, dry cough
Pleural sacs
- there are 2 of them, so if one is damaged the other one can still function
- Thoraic wall - parietal pleura - intrapleural fluid - visceral pleura - lung
intrapleural fluid
lubrication fluid between pleura layers
Intrapleural space has relative _____ pressure to help keep lungs from collapsing in
negative
-chest wall is always pulling out, lungs are elastic and always pulling in = these forces create a negative pressure
Pleurisy
painful irritation / friction of the inter pleural space
what is pleurisy caused by:
inflammation (infection, chemical exposure) and build up of an irritant (bleeding infection)
Tx of pleurisy
drain fluid or decrease the inflammation, then treat source
Ventilation
getting oxygen into the alveoli: breathing
Ventilation problems
respiratory muscle paralysis; high altitude; foreign body obstruction; laryngospasm; alveolar collapse (atelectasis); asthma; airway damage (smoking)
Exchange
getting O2 into the blood and CO2 out of the blood
Exchange problems:
Pulmonary edema; pulmonary fibrosis; carbon monoxide poisoning; anemia; pulmonary embolus (oxygen comes in but theres no blood arriving to pick it up); asthma
-everything rolls downhill
Is O2/CO2 ratio even or not?
not even, CO2 is lower
PO2 pressure in the air
160 mmHg
PCO2 pressure in the air
0.3 mmHg
PO2 pressure in alveoli
105 mmHg
PCO2 pressure in alveoli
40 mmHg
PO2 in pulmonary veins, left heart, systemic veins
100 mmHg
PCO2 in pulmonary veins, left heart, systemic veins
40 mmHg
PO2 in systemic veins, right heart, pulmonary arteries
40 mmHg
PCO2 in systemic veins, right heart, pulmonary arteries
46 mmHg
Transport
get oxygen to the tissue
transport problem:
left heart failure and many other pump failures (taxis are loaded but not moved out; arterial thrombosis; arterial bleeding; sickle cell disease
Exchange
get O2 from blood into tissue cells and CO2 from tissue cells into blood
exchange problems
peripheral edema; abnormal oxygen dissociation (acidosis or alkalosis)
Utilization
oxygen consumption in the tissues
problems with utilization
venous bleeding; sickle cell disease; shock; venous thrombosis
Transport of CO2
CO2 must dissolve in liquid to diffuse through plasma membranes, it also diffuses across 2 cell membranes to get to the plasma
- some CO2 travels within the plasma
- Some CO2 travels enters the RBC and travels bound to hemoglobin
- Some CO2 travels within RBC but free from hemoglobin
Bicarbonate equilibrium
CO2+H2O <=> H2CO3 <=> H+ + HCO3-
how much CO2 travels via bicarbonate equilibrium
30%
why is bicarbonate so important
its a buffer
enzymes work best at pH 7.44
CO2 is controlled by what
the lungs
bicarbonate is controlled by what
kidneys
what 2 things buffer the blood stream
- deoxyhemoglobin
- bicarbonate buffer system
what controls respiration
PONS and the medulla
what are the 2 chemo-receptors
peripheral and central
peripheral chemo-receptors
- sensitive to levels of O2, H+ and high CO2
- you respond to high levels of CO2 first
central chemo-receptors
- only sensitive to pH
- these are the receptors that are shut down by alcohol and drugs by suppressing the medullas respiratory pacemaker