Week 1 Pulmonary Flashcards
what is the sternal angle?
-formed by articulation of manubrium with the body of the sternum
-the point from which all costal cartilages and ribs are counted
-marks the level of bifurcation of the trachea into the right and left main stem bronchi
where does the sternal angle lie?
-at the level of 2nd costal cartilage
-opposite the intervertebral disc between T4&T5
which ribs are true, false, and floating?
1-7 = true (vertebrosternal connection)
8-10 = false (have vertebrochondral connection)
11-12 = floating (only vertebral connection)
what is ventilation?
the process of moving air in and out of the lungs
what is the purpose of the respiratory system?
maximize gas exchange
what is happening during inspiration?
-the diaphragm contracts and flattens elevating the lower ribs and pushing the upper ribs and sternum up and out
-chest cavity elongates and enlarges
-intrapulmonic pressure decreases allowing air to follow the pressure gradient and come in
is expiration passive or active?
usually passive except during strenuous exercise (internal intercostals and abdominal muscles are used)
what is the valsalva maneuver?
-the closing of the glottis following a full inspiration while maximally activating the expiratory muscles
-results in an increase in intrathoracic pressure helping stabilize the chest during lifting
what are the types of pleuritis or pleuritic pain?
hemothorax (blood), pneumothorax (air), empyema (pus), and pleural effusion (swelling)
what is pleura?
two membranes surrounding the lungs
what is the hilus?
the point at which the nerves, vessels, and primary bronchi penetrate the parenchyma
what is the difference between the right and left lung?
no middle long on the left
where is a tracheostomy tube placed?
between the second and third tracheal rings
where is gas exchanged allowing oxygen to enter into the bloodstream and carbon dioxide to leave?
bronchioles and alveoli
what is fick’s law?
if surface area decreases or thickness increases then gas diffusion decreases
-gas diffuses through the tissue at a rate proportional to the surface area and inversely proportional to its thickness
what is surfactant and why is it important?
-lipoprotein lubricant mix of phospholipids, proteins, and calcium produced by the alveolar epithelial cells
-without it our lungs would stretching out on inspiration and collapse on expiration (balloon)
-keeps surface tension on alveoli
what is the conducting zone of the airway?
(dead space)
trachea, primary bronchus, bronchus, bronchi, bronchioles
what is the transitional and respiratory zone of the airway?
(where gas exchange takes place)
respiratory bronchioles, alveolar ducts, alveolar sacs
what is the difference between ventilation and respiration?
respiration = exchange of gases
ventilation = moving air in and out of lungs
what is tidal volume?
normal breathing at rest
= between 0.4 and 1 liter per breath
what is inspiratory reserve volume?
the amount of space you have above tidal volume to increase inspiratory breath at rest
= about 2.5-3.5 liters
what is expiratory reserve volume?
the amount of space you have below tidal volume to breathe out
what is force vital capacity?
the summation of IRV + TV + ERV
= about 3-5 liters
decreases with age or if not utilized
what is residual lung volume?
the dead space you can’t breathe out
= about 0.8-1.4 liters
increases with age
what is total lung capacity?
the summation of FVC + RLV
during exercise what happens to IRV, ERV and TV?
IRV + ERV decrease
TV increases
what does the amount of air ventilated depend on?
the maximal force vital capacity of the lungs and the velocity of flow (influenced by lung compliance)
what is FEV1/FVC?
pulmonary airflow capacity
= ~85% of FVC in 1 second
obstructive diseases result in significant lower FEV1/FVC
what does training do to lung volumes?
increases lung volumes except for tidal volume
what is the purpose of the pulmonary system?
to maximize gas exchange
to increase exchange
what is the most common obstructive lung condition? what is it caused by?
asthma
caused by irritation of the lining of the bronchioles that decreases the airway size
what does the oxygen pressure difference do?
drive the movement of oxygen towards the tissues and carbon dioxide towards the atmosphere
what is henry’s law?
gases diffuse from high pressure to low pressure
what does gas diffusion rate depend on?
pressure differential and the solubility of the gas in the fluid
what happens to the gas transfer capacity in pulmonary disease?
may be impaired by the thickening of membrane and a reduction in surface area
what is the average arterial blood gas levels? PO2 and PCO2
PO2 = 100 mmHg
PCO2 = 40 mmHg
what are the two mechanisms for O2 transport?
dissolved in plasms (for carotid sensors) and combined with hemoglobin
when normal Hb level exist each dL of blood contains about how much O2?
20 mL
what is happening with the blood oxygen when a person has iron deficiency anemia?
they have reduced oxygen carrying capacity up to half as much )2 can be carried. as a result the heart rate will increase.
what is the oxyhemoglobin dissociation curve?
-illustrates the saturation of hemoglobin with oxygen at various PO2 or partial pressures of oxygen
-as the partial pressure goes up the saturation of hemoglobin goes up.
what are the 3 methods of CO2 transport?
- dissolved CO2 establishes the partial pressure of carbon dioxide in the blood (5%)
- plasma bicarbonate in solution: carbon dioxide combines with water to form carbonic acid (60-80%). helps with buffering acids during exercise
- bound to hemoglobin directly (20%)
what is the haldane effect?
Hb interaction with O2 reduces its ability to combine with CO2. this aids in releasing CO2 in the lungs
why does the rate and depth of breathing matter?
shallow breathing: only going in and out of dead space. will decrease the pressure differences and slow gas exchange at the alveolar level
how does rate and depth of breathing affect alveolar ventilation?
increases
during increased demand (exercise) what happens to rate and depth of breathing?
initially larger increases in depth occur, followed by increases in both rate and depth
what is alkalosis?
increased pH - lungs rid of CO2
what is acidosis?
decreased pH - kidneys rid bicarbonate
what three mechanisms help regulate internal pH?
chemical buffers, pulmonary ventilation, renal function
how does acid-base regulation occur?
takes place using chemical buffering in the blood
the renal system: becomes more basic and removes bicarbonate
the lungs remove CO2 when the blood becomes more acidic by increasing ventilation
