Final Written Flashcards
Which respi ms?
With the head fixed, it elevates the sternum and increases the AP diameter.
SCM
Which respi ms?
Braces and stabilizes the scapula, enabling other muscles to elevate the ribs.
Traps
Which respi ms?
When the scapula is fixed, it acts to elevate the rib to which it is attached.
Serratus anterior
Which respi ms?
When its superior attachment is fixed, it elevates the first 2 ribs during inspiration.
Scalenes
Which respi ms?
When the arms are fixed, it draws the ribs towards the arms, thereby increasing thoracic diameter.
Pec major
T or F
In sidelying, the uppermost lung fields are preferentially ventilated compared to the lowermost lung fields.
F
T or F
The main accessory muscles of breathing tend to increase the transverse diameter more than the anterior posterior (A-P) diameter of the thorax.
F.
T or F
The primary muscles of inspiration are active only during quiet breathing.
F
T or F
The parasternals are primary muscles of inspiration.
T
T or F
The rectus abdominus contributes most to increasing intra-abdominal pressure during a forced expiration.
F
T or F
The upper airway muscles are more active during sleeping.
F
T or F
At the start of inspiration, the upper regions of the lungs are inflated more than the lower regions.
T
T or F
There is more blood in the dependent areas of the lung.
T
T or F
Activation of the abdominal muscles during expiration results in diaphragm shortening.
F
T or F
Diaphragm excursion is greater in sitting than in supine.
F
It’s the opposite.
Which of the following occur(s) during inspiration?
A. Intra-abdominal pressure decreases B. Pleural pressure decreases C. Intra-thoracic pressure increases D. Intra-alveolar pressure equals atmospheric pressure E. None of the options provided
B. Pleural pressure decreases
An individual can have a weak cough due to which of the following?
A. Poor closure of the vocal chords B. Damaged and ineffective beating cilia C. Weak inspiratory muscles D. Weak expiratory muscles E. None of the options provided
A. Poor closure of the vocal chords
C. Weak inspiratory muscles
D. Weak expiratory muscles
T or F
The bronchial arteries deliver deoxygenated blood from the right ventricles to the lungs.
F
Which of the following airways have cartilage in their walls?
A. Segmental bronchi B. Lobar bronchi C. Trachea D. Lobular bronchioles E. Terminal bronchioles
A. Segmental bronchi
B. Lobar bronchi
C. Trachea
T or F
An increased accumulation of fluid in the pleural space is call a pneumothorax.
F
T or F
Pulmonary arteries dilate in the presence of hypoxia.
F
T or F
Mild hypoxic vasoconstriction will lead to pulmonary hypertension.
F
T or F
Hypoxic vasoconstriction increases dead space.
F
T or F
Dead space is increased by shallow breathing.
T
The primary cause of a decline in DLco in a patient following removal of a lung lobe (Lobectomy) is:
A. Decreased pulmonary blood flow B. Decreased alveolar surface area C. Decreased diffusion across the alveolar-capillary membrane D. Decreased V/Q matching E. All or none of the above
B. Decreased alveolar surface area
T or F
Lung fissures may appear shifted in the presence of lung pathology.
T
T or F
In a properly exposed chest x-ray, the intervertebral spaces can be very clearly seen to be superimposed on the shadow of the heart.
F
T or F
“Lung markings” visible on chest x-rays are the larger airways that branch out from the mediastinum to the periphery.
F
T or F
The definitive location of lung pathology can be established solely from the PA view when the silhouette sign is present.
F
T or F
Lateral decubitus films can be helpful in identifying the presence of increased fluid in the pleural space
T
T or F
The PEFR has a high variability precluding its clinical usefulness.
F
T or F
A 20% improvement in PEFR is the gold standard for evaluating a significant response to bronchodilator.
F
T or F
The FEF25-75% is the average volume that is exhaled during the middle portion of the FVC.
F
T or F
The FEV1/FVC ratio must be greater than 70% of the predicted value to be considered normal.
F
A patient has the following blood gas values: pH=7.32, PaCO2=68, and HCO3-=28. Which of the following statements is the MOST accurate interpretation?
A. Uncompensated metabolic acidosis
B. Partially compensated metabolic acidosis
C. Partially compensated respiratory acidosis
D. Uncompensated respiratory acidosis
E. None of the above
C. Partially compensated respiratory acidosis
What does it mean when someone has a mixed acid-base disorder? How is it identified?
A disorder of metabolic and respiratory alkalosis and acidosis. It is identified when an apparent compensatory change is not in the same direction of as the primary disorder. It can also be a mixed acid-base disorder if the compensation is greater than what is expected based in the rule of thumb.
T or F
The silhouette sign on a CXR occurs when structures of different density are next to each other.
F
T or F
The location of the silhouette sign can assist in identifying the location of the lung pathology.
T
T or F
Deviation of the trachea is identified by the silhouette sign.
F
T or F
A lateral film may be necessary to confirm a pathology in the right lower lobe (RLL).
T
Abnormalities in which of the following electrolytes can result in an altered level of consciousness?
A. Na+
B. K+
C. Cl-
D. Ca2+
A. Na+
D. Ca2+
Which of the following is/are a sign of respiratory distress.
A. Jugular venous distention B. Nasal flaring C. Diaphoresis D. Hyperinflation E. None of the above
B. Nasal flaring
C. Diaphoresis
Which of the following pathological features relate(s) to COPD?
A. Destruction of the alveolar walls. B. Inflammation of the mucosal lining of the airways. C. Retained secretions. D. Hyperinflation of the alveoli. E. None of the answers provided.
A. Destruction of the alveolar walls.
B. Inflammation of the mucosal lining of the airways.
C. Retained secretions.
D. Hyperinflation of the alveoli.
Which of the following pathological changes contribute to the reduction in lung elastic recoil that occurs in a patient with COPD secondary to inhaled cigarette smoke?
A. Narrowing of the airways. B. Hypertrophy of the submucosal glands. C. Reduction in airway remodeling. D. Loss of alveolar attachments. E. None of the answers provided.
D. Loss of alveolar attachments.
A patient with COPD with a score of 8 on the Bode index is associated with which of the following?
A. High mortality rate B. Less severe COPD C. Stage II COPD D. FEV1=50% E. None of the above
A. High mortality rate
What abnormal physiological change develops in response to the presence of arterial hypoxemia in a patient with COPD?
A. Polycythemia B. Tachypnea C. Thrombocytopenia D. Anemia E. None of the above
A. Polycythemia
T or F
Individuals with asthma have a higher rate of FEV1 decline compared to healthy individuals.
T
T or F
Mucous hypersecretion in asthma increases the rate of FEV1 decline over time.
T
T or F
Exercise induced asthma is defined as a decline in FEV1 or PEF after exercise of at least 15%.
F
T or F
Symptoms of exercise induced asthma only appear following exercise.
F
T or F
Certain secretion clearance techniques should not be used with patients who have asthma because they may trigger bronchospasm.
T
Which of the following is/are NOT typically seen in patients who have asthma?
A. Mucopurulent secretions B. Finger clubbing C. Dyspnea D. Wheezing E. Cor pulmonale
A. Mucopurulent secretions
B. Finger clubbing
E. Cor pulmonale
An irreversible dilatation of one or more bronchi with chronic inflammation and infection is characterized by which of the following lung diseases?
A. Emphysema
B. Chronic bronchitis
C. Bronchiectasis
D. Asthma
C. Bronchiectasis
Wheezes are described by which of the following auscultated sounds?
A. Soft, low-pitched sounds heard primarily during inspiration.
B. Discontinuous adventitious lung sounds similar to brief bursts of popping bubbles.
C. An abnormal sound similar to two pieces of leather or sandpaper rubbing together.
D. Continuous adventitious lung sounds with a constant pitch and varying duration.
E. None of the above
D. Continuous adventitious lung sounds with a constant pitch and varying duration.
Which of the following conditions would increase transmission of lung sound?
A. Consolidation B. Shallow breaths taken C. Obesity D. Pulmonary hyperinflation E. None of the answers provided
A. Consolidation
What are the 3 roles of the nose?
Filters air
Humidifies air
Warms air
What is the role go course hairs in the nose (vibrissae)?
Trap inhaled particles
What is the role of the nasal chonchae?
Increase the surface area
What is the role of the mucous and the serous secretions in the nose?
Trap foreign particles and bacteria
What is the impact of smoking on the ciliated epithelium of the nose?
Smoking paralyses the cilia = decrease the filtering capacity of the nose = increase risk of developing infection
What are the 3 roles of the pharynx?
Swallowing
Coughing
Gag reflex
What is the role of the epiglottis?
Protects the airway from food
What are the 2 roles of the larynx?
Talking
Coughing
How are called the 2 cartilages found in the larynx?
Cricoid
Thyroid
What is the rima glottis?
Opening in the vocals chords of the larynx
What is the default position of the rima glottis?
Open
What is the position of the rima glottis during forced expiration?
Vocal chords are
Widened
Vocal chords are ABD or ADD during forced expiration?
ABD
Vocal chords are ABD or ADD during speech?
ADD
What is the position of the rima glottis during coughing?
Closed to increase intrathoracic pressure when the larynx is open
What are the anatomical landmarks for the trachea?
C6 -> T4
Where is the carina?
T4
Is the trachea in front or behind the esophagus?
In front
T or F
R mainstream bronchus is shorter and wider and deviates less from the axis of the trachea than the L
T
What is the clinical significance concerning the difference btw the R and L mainstem bronchus anatomical position?
R lung is more likely to have complication (infections) bcuz tubes are more likely to slip into it due to the deviation from the midline axis is smaller and bronchus is shorter/wider
How many lobes in the R lung?
3
How many lobes in the L lung?
2
Which generation are in the conducting airways?
1-16
What 4 structures are considered upper airway?
Nose
Pharynx
Epiglottis
Larynx
What 3 structures are considered lower airway?
Trachea
Airways
Alveoli
What is the purpose of the conducting airways?
Tranport gas to the respiratory bronchioles and alveoli
Which 3 “structures” are considered the conducting airways?
Lobar bronchi
Segmental bronchi
Terminal bronchioles
The terminal bronchioles extend from which generations?
12-16
The terminal bronchioles extend from which generations?
12-16
What is the lung parenchyma?
pulmonary alveoli and respiratory bronchioles
substance of the lung that is involved with gas exchange
What keeps the terminal bronchioles open?
The elastic properties of the parenchyma bcs these bronchioles are embedded in the parenchyma
Which structure is found in the transitional zone of the lung?
Respiratory bronchioles
The respiratory bronchioles extend from which generations?
17-19
T or F
Respiratory bronchioles have occasional alveoli budding from their walls.
T
T or F
In the respiratory bronchioles, the number of alveoli decreases with each generation.
F
it increases
How big is the anatomical dead space?
150 mL
What is essential to maintain the lumen of the respiratory bronchioles and why?
Traction of the parenchyma as the walls of the bronchioles are buried in the lung parenchyma.
Where does the gas exchange happen in the lung?
Respiratory zone
What are 2 structures found in the respiratory zone?
Alveolar duct
Alveolar sac
The alveolar ducts extend from which generations?
20-22
The alveolar sac extend from which generations?
23
Which structure represent the end of the lung?
Alveolar sacs
What are the walls of the alveolar ducts composed of?
Alveoli
Which 4 lung structures composed an acinus?
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli
Alveolus are made primarily of which type of cells?
Epithelial cells
What is the name of the structure that acts as a communication between the bronchioles and the alveoli?
Canals of Lambert
What is the name of the channels in the alveolar walls?
Pores of Kohn
What is the angle of Louis?
Joint btw manubrium and sternum
Where the 2nd rib inserts
In which thoracic cavity the lungs would be in an X-ray?
posterior mediastinum
T or F
The intrapleural fluid is between the parietal pleura and the visceral pleura.
T
The axis of rotation of the ribs is defined by what?
Articulation w/ TP
For the upper ribs, how is the articulation aligned? What is their role?
Articulation nearly parallel to the frontal plane = pump-handle motion
Increase the AP diameter
For the upper ribs, how is the articulation aligned? What is their role?
Articulation nearly parallel to the frontal plane = pump-handle motion
Increase the AP diameter
For the lower ribs, how is the articulation aligned? What is their role?
Articulation is oriented dorsally = bucket-handle
Cause lateral displacement of thoracic cage
What are the 3 primary inspiratory muscles?
Diaphragm
External intercostals
Parasternals
What are the 6 inspiratory accessory muscles?
Scalenes SCM Pec major/minor Serratus anterior Trapezius Erector spinae
What are the 2 expiratory muscles?
Abs
Internal intercostals
Why does diaphragm works less in sitting/standing compared then supine?
Gravity pulls on the muscles, making it harder for it to contract
T or F
The diaphragm contributes to 40% of the vital capacity.
F
60%
Guess who
I arise from the bodies of the first threes lumbar vertebra and extend to the central tendon.
Crural portion of the diaphragm
Guess who
I arise from the inner surfaces of the lower four ribs and lower six costal cartilages. I insert into the anterolateral part of the central tendon.
Costal portion of the diaphragm
Which nerve innervates the diaphragm? What are the spinal levels of this nerve?
Phrenic nerve
C3-C4-C5
Guess who
Area where the diaphragm is directly apposed to the rib cage. I represent 30% go the total surface ares of the rib cage.
Zone of apposition of the diaphragm
Explain the appositional component of the diaphragm function.
Rise in intra-abdo pressure during inspiration is transmitted through the apposed diaphragm to expand the lower rib cage
Appositional force greater when the zone of apportion and the rise in abdo pressure are larger
Explain the insertional component of the diaphragm action
During inspiration, as the costal diaphragm fibers contrat and shorten, they exert a force on the lower ribs. If the abdo viscera opposes and resists the descent of the diaphragm dome, the force will be oriented cranially and the ribs will be lifted and rotated outwards.
What is the thoraco-abdominal synchrony in breathing?
During inspiration, the abdomen and the thorax both move outwards (diaphragm contracts, chest expands) pleural and alveolar pressures drop and air flows into the lungs.
T or F
The external intercostals are more deep than the internal intercostals.
F, they more superficial
What is the innervation of the intercostal muscles?
Adjacent intercostal nerves
Guess who
I elevate the lower rib cage and descent the sternum. I am always active during inspiration when the diaphragm contracts.
Parasternal intercostal muscles
Guess who
I am the ease with which a lateral stretches when an external force is applied to me. I depend on volume and pressure.
Compliance
Guess who
I am the stiffness to a stretch.
Elastance
How does the lung act during inflation/deflation if it is filled with saline?
Distending pressure are the same during inflation and deflation
How does the lung act during inflation/deflation if it is filled with air?
Higher pressure on inflation and lower on deflation
What is hysteresis?
The fact that the inflation and deflation curves are not the same when the lungs are filled with air (normal breathing).
Results from the effects of surface tension forces caused by air-liquid interface in the alveoli
What is responsible for the lung’s elastic behavior? (2)
- Elastic tissues of the lung
- Elastin and collagen fibers in alveolar walls, vessels and bronchi
- Geometrical arrangement of the fibers (nylon stocking) - Surface tension forces in the lung caused but the alveolar-liquid interface
Surfactant is secreted by who?
Type II pneumocystises
Why does premature babies sometimes have respiratory problems?
Don’t have type II pneumocystes so lungs are stiffer and less compliant.
What are the 3 functions of surfactant?
- Reduces surface tension in the alveolar lining fluid = reduce tendency of alveolus to collapse
- Increases lung compliance
- Prevents transudation of fluid into alveoli = less negative pressure in the interstitial space -> lower hydrostatic pressure gradient btw pulmonary capillary and interstitial space
What can decrease lung compliance? (4)
- Intersitial edema = fluid in interstitial fluid outside alveoli (early HF)
- Pulmonary edema (HF = pressure going back up into lungs)
- Decrease ventilation of lung for an extended period (inflation of lung increases surfactant production)
- Diseases causing pulmonary fibrosis
What can increase lung compliance? (2)
Age
Emphysema
Guess who
P alveolar - P barometric
Transrepiratory (trans-total system) pressure
Guess who
P alveolar - P pleura
Transpulmonary pressure
Guess who
P pleura - P barometric
Transthoracic (trans-chest wall) pressure
On inspiration, what happens to :
- Alveolar pressure
- Intrapleura pressure
- Decreases then increases until reach 0
2. Decreases
On expiration, what happens to :
- Alveolar pressure
- Intrapleura pressure
- Increases then decreases until reach 0
2. Inceases
Airflow is driven by what?
Changes in alveolar pressure
If Palv < Patm, where the airflow goes?
Into the lungs
If Palv > Patm, where the airflow goes?
Out of the lungs
If Palv = Patm, where the airflow goes?
Nowhere, there is no flow
Guess who
Pressure difference btw alveolar and atmospheric pressure divided by airflow.
Resistance to airflow
What these factors will do on airway resistance?
- Reduced lung volumes
- Increased bronchial motor tone
- Reduced airway caliber
- Increase in density and viscosity of inspired air
Increase airway resistance
T or F
Total cross-sectional area decreases as descend the tracheo-bronchial tree, causing an increase in airflow
F, it increases and causes a drop in flow
The biggest airway resistance is where in the respiratory system?
Nose, mouth, upper airway
T or F
Airway obstruction in the smaller airways can often go undetected.
T
Explain dynamic airway collapse during forced expiration.
Dynamic pressure drop from alveolus to the airway is caused by airway resistance
Pressure in the lumen of the airway may be lower than the external wall pressure (-ve transmural pressure), leading to collapse of airway
In emphysema, how is the P alveolar different from healthy pt?
P alveolar is smaller bus lung is less elastic (more compliant, more floppy)
T or F
As pH decreases, ventilatory rate increases which in turn lowers the CO2, eventually returning the body to a homeostatic balance.
T
T or F
Both CO2 and O2 diffuse through the blood-brain barrier which separates the CSF and arterial blood.
F, only CO2 crosses
T or F
More CO2 = more H+ = decreased pH
T
Which receptors are responsible to respond to H+ dissolved in the CSF?
Where are they located?
Central chemoreceptors
Below the ventrolateral surface of medulla
Which receptors are responsible to sense PO2, PCO2 and pH of arterial blood?
Where are they located?
Peripheral chemoreceptors
Aortic bodies located on the aortic arch +
Carotid bodies located at the bifurcation of internal and external carotid arteries in neck
What is the threshold for a clinically significant response from the peripheral receptors?
60 mmHg = very hypoxemic
Ventilatory response to CO2 is modified by? (4)
- State of wakefulness
- Acid-base status of body
- Narcotics, anesthesia, alcohol
- Arterial oxygenation
What is the difference of the pleural pressure in the base of the lung vs in the apex?
Why?
Pleural pressure is less in negative (so bigger) in the base
Bcs of the weight of the lung
What is the difference of the compliance in the base of the lung vs in the apex?
What’s the impact?
Better compliance at the base of the lung
Basal lung expands better on inspiration
What is the dependent areas of lung?
The lowest part of the lung in relation to gravity.
T or F
Distribution of ventilation (airflow) is lower in dependent area of the lung
F, it is greater in lower part of lung because compliance is better.
T or F
Gravity dependent regions of the lung get more blood aka better perfusion.
T
Where in the lung is the best V/Q matching?
Base of the lung
Bcs better ventilation and better perfusion
Which rib level is the optimum gas exchange?
Rib 3
Guess who
Perfusion but no ventilation. V/Q = 0
Shunt (aka blockage in airways)
Guess who
Ventilation but no perfusion. No gas exchange. V/Q = infinity
Dead space
Guess who
I am the most cost effective test in medicine.
Chest x-ray
On radiography, more dense structures appear which color?
Why?
White
Block the radiation so won’t expose it on the image
On radiography, less dense tissues appear which color?
Black
What are the 3 common views on chest radiography? Describe each.
AP = plate is behind, radiations passing from front
PA = plate is in front, radiations passing from behind
Lateral projections = plate on one side and radiations passing from the other
AP view for chest radiography is usually used when?
When a portable x-ray is required for pt on bed rest
T or F
Heart can appear enlarged and its outline softer with AP because the heart is closer from the x-ray plate.
F
Heart is further from the plate
When supine, how the diaphragm move? How does this impact the lung volume?
Diaphragm pushed up which decreases lung volume
How do you orient the film properly on the screen to read a chest x-ray?
Pt has to be facing you = their L is on your R
T or F
On a normal film, the intervertebral spaces should be superimposed (darker areas) on the shadow of the trachea.
T
What over-exposed film means?
How can you know a film is over-exposed?
Increased blackness
If intervertebral spaces are clearly apparent superimposed on the shadow go the heart = film is too black
What under-exposed film means?
Increased whiteness
If intervertebral spaces are not apparent superimposed on the shadow of the trachea and heart = film is too white
If on a film the trachea is off center and the clavicles are not at a uniform distance from the midline, what could that mean?
pt is rotated
What is the landmark to evaluate the lung volumes in a chest x-ray?
If lung volumes are normal, the anterior end of the 5-7 ribs should be visible above the diaphragm int he mid-clavicular line.
What are the 2 landmarks to evaluate the mediastinal structures in a chest x-ray?
- Trachial shadow should be in mid-line (black tube over Cx spine)
- Carina overlies the 4th Tx vertebrae
What are the 4 landmarks to evaluate the heart and great vessels in chest x-ray?
- Heart shadow slightly to the L and in contact w/ diaphragm
- Aortic knob L of midline
- Cardiothoracic ratio should not me greater than 50%
- Cariophrenic angle should be apparent
A cardiothoracic ratio greater than 50% is a sign of what?
Enlarged heart that can be caused by hypertension or other conditions (usually to R heart)
T or F
R hemidiaphragm should be higher than L hemidiaphragm.
T
Because liver is on the R side
T or F
Bubbles under L hemidiaphragm is abnormal.
F
It is normal because of stomach or splenic flexure
T or F
Costophrenic angle can disappear on film when there is a condition
T
Pleural effusions can make this angle disappear due to accumulation of fluid in the pleural space
What we look for in normal chest x-ray when evaluating the lung fields and boundaries? (3)
- Lung boundaries in contact w/ chest wall and diaphragm
- Pleura not visible
- Vascular markings are visible
If there is a pneumothorax, what will appear on the chest x-ray?
No vascular markings = everything is black in lung area
Guess who
I am the profile of soft tissues superimposed on the lung fields on a chest x-ray.
Silhouette sign
T or F
Absent silhouette sign is indicative of airspace disease or fluid-occupying lesions.
T
T or F
Atelectactic or pneumonic lungs appear denser then soft tissues on a chest x-ray.
F
They all have the same density
T or F
Consolidation or collapse density similar to that of heart or muscle
T
T or F
Image of the collapsed lung will become confluent with the heart or diaphgram and respective borders will be obliterated.
T
T or F
Diaphragm in black in a lateral chest x-ray
F
It is white and superimposed
What are the 2 most common tests for lung function?
Spirometric
Lung volume measures
What exactly is assess in spirometry?
Which exact parameter?
Mechanical state of the lung
FEV1 and FVC
Guess who
I am the volume exhaled in the 1st second of a forced expiration.
FEV1 aka proved expiratory volume
Guess who
I am the total volume exhaled in an forced expiration.
FVC aka forced vital capacity
T or F
FVC is slightly more than the slow vital capacity.
F
FVC is slightly less than slow vital capacity
T or F
FEV1 is about 80% of slow FVC
T
What is the normal ratio of FEV1/FVC?
80%
What FEV1/FVC ratio is considered an obstructive disease?
What will the FVC look like for obstruction?
ratio < 70%
FVC = normal or low
What can cause a reduction of FEV1? (4)
- Reduction of TLC
- Obstruction of airways
- Loss of lung recoil
- Significant weakness of respiratory ms
If there is a lung restriction, what will FEV1/FVC and FVC will look like?
What about lung volumes?
ratio = normal
FVC = low
smaller lung volumes = lungs can’t expand as much
Body plethysmography, helium dilution and nitrogen washout are methods to measure which pulmonary capacity?
FRC = functional residual capacity
How does TLC and RV can be calculated?
Once FRC is measured with fancy equipment and VC is obtained w/ spirometry, use subtraction
Guess who
I measure the ability of a gas to transfer from alveolar gas into the pulmonary capillary blood.
Diffusion capacity (DLco)
What are the 4 major factors determining DLco?
- Gas exchange surface area (lung-blood interface)
- Thickness of alveolar wall
- Difference btw partial pressure of the gas in the alveolus and in the red blood cell
- Blood flow to the alveoli that receive ventilation
How is the DLco measured?
Pt blow into machine that calculate the concentration of CO picked up by the blood
What is the cut off for normal DLco?
+/- 20% predicted (80-120% predicted)
T or F
Exercise can increase DLco.
T. Can increase it by 2x
All these factors can be a sign of ___ diffusion capacity?
- Anemia
- Increased interstitial fluid (CHF, renal failure)
- Mismatching of alveoli and capillaries (COPD, pulmonary vascular disease)
- Thickening of alveolar capillary membrane (fribrosing alveolitis)
- Reduced area of alveolar capillary membrane (emphysema)
Reduced
What is the %change after bronchidilatator to conclude that is it is effective and thus suggesting asthma?
12-15%
Normal value for pH (range)
7.40 (7.35-7.45)
Normal value for PaO2 (range)
90 mmHg (80-100)
Normal value for PaCO2 (range)
40 mmHg (35-45)
Normal value for HCO3 (range)
24 mEq/L (22-26)
Normal value for BE
+/- 2
Guess who
Increase in blood H+ by retention of CO2 due to decrease alveolar ventilation.
Respiratory acidosis
Guess who
Decrease in blood H+ from blowing off CO2 due to increase alveolar ventilation.
Respiratory alkalosis
Guess who
Increase in blood pH from ingestion, infusion, production of a fixed acid or elimination of HCO3.
Metabolic acidosis
Guess who
Decrease in blood pH by excessive loss of fixed acids or ingestion, infusion of HCO3 or alkalides.
Metabolic alkalosis
What is the difference btw the compensations for the respiratory system vs the renal system?
Respiratory = rapid compensation (w/i min) Renal = slow compensation (hours-days)
What is the difference btw a partial compensation and a full compensation?
Partial compensation = change in PaCO2 or HCO3 but pH is still abnormal
Full compensation = change in PaCO2 or HCO3 but pH is normalized
How the respiratory acidosis is compensated?
Increase in HCO3, increase BE
How the respiratory alkalosis is compensated?
Decrease in HCO3, decrease BE
How the metabolic acidosis is compensated?
Decrease in PaCO2
How the metabolic alkalosis is compensated?
Increase in PaCO2
These expected compensation is related to which primary disorder:
- For a 10 mmHg increase in PaCO2, the HCO3 increases 1 mEq/L
- For every 10 mmHg decrease in PaCO2, HCO3 decreases 2 mEg/L
- If HCO3 > 30 mEq/L
- PaCO2 = (1.5x HCO3) + 8 +/-2
- PaCO2 change is variable but doesn’t elevate above 50-55 mmHg
- Acute respiratory acidosis
- Acute respiratory alkalosis
- Chronic respiratory acidosis
- Metabolic acidosis
- Metabolic alkalosis
What are the 5 more common causes of hypoxia?
Alveolar hypoventilation Diffusion impairment V/Q mismatch Shunt High altitude