Oxygen Transport Flashcards
What are the goals of cardiopulmonary physical therapy?
- Reverse of mitigate insults to O2 transport
2. Reduce the need for medical interventions
___% of oxygen is dissolved in blood plasma.
1.5
___% of O2 is combined with Hb.
98.5
Hb molecules can transport up to ___ O2 molecules.
4
Hb affinity for O2 ______ as it’s saturation increases.
increases
Resting organs have a PO2 of ___ mmHg and is ___% saturated.
40; 75
Lungs at sea level have a PO2 of ____mmHg and Hb is ___ % saturated.
100; 98
Actively contracting muscles has a PO2 of ___mmHg and Hb is only ___% saturated.
20;35
In addition to PO2, what other 4 factors alter Hb?
- pH
- Temp
- PCO2
- 2,3-DPG
What is the Bohr effect?
Hb saturation curve shifting to the RIGHT
Hb saturation curve shifting to the right causes (increased/decreased) O2 unloading?
increased
What are the 8 steps in the O2 cascade?
- Inspired O2 and quality of ambient air
- Airways
- Lungs and chest wall
- Diffusion
- Perfusion
- Myocardial function
- Peripheral circulation
- Tissue extraction
Chronic irritation of the lungs can lead to what 4 things?
- Allergies
- Chronic inflammatory reactions
- Fibrosis
- Alveolar-capillary membrane thickening
Edema, mucus, foreign, objects, particulate matter, lesions and hyperactivity of bronchial smooth muscles can all lead to?
Increased resistance to airflow
Air entry into the lungs depends on the integrity of what 3 things?
- Respiratory muscles
- Lung parenchyma
- Chest wall
Obstructed airways, increased lung compliance and increases in airway resistance all increase the time needed for _______ _______.
alveolar filling
Gas exchange is compromised if there is inadequate time for alveolar _________ or ________.
filling; emptying
Lung unit with a _____ time constant is slow to fill and empty, and it can continue filling when surrounding units are emptying.
long
In upright lungs, are the bases or apices better perfused?
bases
_________ regulate blood flow through regional vascular beds and maintain peripheral vascular resistance and thus systemic blood pressure.
arterioles
What are the 9 steps in the intervention hierarchy to manage O2 transport limitations?
- Mobilization and exercise
- Body positioning
- Breathing control maneuvers
- Coughing maneuvers
- Relaxation and energy conservation techniques
- ROM exercises
- Postural drainage positioning
- Manual techniques
- Suctioning
The respiratory system (does/does not) adapt to exercise training.
DOES NOT
Does the respiratory system limit exercise?
In highly trained men and women, possibly
What are 2 potential respiratory system limitations?
- Exercise induced arterial hypoxemia
2. Respiratory muscle fatigue and steal of skeletal muscle blood flow
EIAH = arterial O2 desaturation of >__-__% below resting levels during exercise.
3-4
EIAH is observed in ~___% of elite male endurance athletes with a VO2 max > 65mL/kg/min.
50
EIAH is characterized by a _______ PaO2 and an _______ alveolar to arterial O2 difference.
decreased; increased
PaCO2 >___ mmHg = inadequate compensatory hyperventilation.
35
What are 2 possible mechanisms of inadequate hyperventilatory compensation?
- Blunted drive to breath (reduced chemrsensitivity)
2. Mechanical ventilatory constraints (expiratory flow limitation)
_____ mismatching is the primary contributor to the development of EIAH.
Va/Q
What is an extra-pulmonary shunt?
deoxygenated blood returning from the exercising muscles bypasses the lungs completely through bronchial and thebesian veins and is dumped into the left atrium of the heart
What is an intra-pulmonary shunt?
deoxygenated blood that passes through the lunges but does not participate in pulmonary gas exchange; venous blood mixes with and dilutes arterial blood
Shunts play a _____ role in exercise gas exchange.
minor
What are the two major determinants of alveolar capillary diffusion during exercise?
- decreased transit time of the RBC’s in the pulmonary capillary
- increased distance for diffusion
What are the 2 functions of the blood gas barrier?
- pulmonary gas diffusion (must be thin)
2. Withstand high capillary wall stressed with exercise (must be strong)
The threshold of EIAH to influence exercise performance occurs when SaO2 decreases by ___-___% below resting levels., Beyond this threshold, each further 1% decrease in SaO2 results in a __-__% decrease in VO2 max.
3-4;1-2
