Pulmonary Phys II: Airflow and Pathologies Flashcards
What 3 factors provide resistance to airflow?
Surface tension of alveoli
Pulmonary compliance
Diameter of bronchioles
_________helps to reduce the surface tension in alveoli
Surfactant
Surfactant molecules pile up into a thicker layer because their _________ regions resist separation from the water below. As they become crowded into a small area and resist layering, they slow and then halt the ________of the alveolus.
hydrophilic
collapse
What condition results from insufficent surfactant?
IRDS- Infant respiratory distress syndrome
What is IRDS?
Infant respiratory distress syndrome-
Premature infants have a deficiency of surfactant and experience great difficulty breathing
What is pulmonary compliance?
The ease with which the lungs expand
Whta happens with greater pulmonary compliance?
The easier it is for a change of pressure to case expansion of the lungs (ventilation)
Name 3 diseases that reduce pulmnocary compliace
Tuberculosis
Pulmonary fibrosis
Black lung disease
Which disease occurs when nodules form in the lung?
Tuberculosis
What is black lung disease?
Coal dust in lungs reduces compliance
What is pulmonary fibrosis?
Replacement of lung tissue with inelastic fibrous CT
How to bronchioles change in diameter?
Smooth muscle changes diamter
What is the term for increasing or decreasing the diamter of bronchioles?
Increase: Bronchodilation
Decrease- Bronchoconstriction
What are 2 bronchodilators?
Epinephresine and SNS
What are 6 bronchoconstrictors?
Anaphylactic shock Histamine (also vasodilates) PNS Cold Air Chemical irritants Asthma
Whta is the volume of anatomic dead air space?
150 mL
With pulmonary disease, which 2 fators decrease pulmonary exchange?
1- Low flow to damaged areas
2- Edema in the lungs/ thickening of respiratory membrane
What is pathalogic dead air space?
Dead air space caused by tissue damage or injury
What is physiological dead air space?
Anatomic dead air space and any pathologic dead air space
What is not used for gas exchange
What is blood acidosis?
blood pH lower than 7.35
What is blood alkalosis?
blood pH higher than 7.45
What is the normal range for blood PCO2?
37-43 mmHg
What is the most common cause of blood acidosis?
What is the PCO2?
Hypercapnia
PCO2 >43 mmHg
What is tx for hypercapnia?
hyperventilation to blow off extra CO2.
Equation shifts to the right, so H+ is consumed
pH rises and blood returns to normal range
What is the most common cause of blood alkalosis?
What is the PCO2?
Hypocapnia
PCO2
What is the tx for hypocapnia?
Hypoventilation, allowing CO2 to accumulate in the body fluids faster than is exhaled.
Equation shifts right, raising H+ concentration
pH lowers to normal range
______ is a deficiency of O2 in a tissue, or the inability to use O2 is often marked by ________, or a blue tinge to tissue.
Hypoxia
Cyanosis
Whta is ischemic hypoxia?
Inadequate circulation of blood
Whta is the cause of histoxic hypoxia?
Caused by metabolic poison,
Whta in an example of a poison that causes hystotoxic hypoxia? How does it work?
cyanide which prevents tissues the tissues from using the O2 delivered to them by stopping e- transport
What causes hypoxemia hypoxia?
Inadequate pulmonary gas exchange
What are some potential causes of hypoxemic hypoxia?
high altitude, drowning, aspiration of foreign object
Respiratory arrest
CO poisoning- prevents Hb from carrying O2
What is AVR?
Alveolar ventilation rate- exchangeable air in 1 minute
350 mL of each 500 mL in tidal breath is exchanged
How is AVR calculated?
AVR= 350 mL x 12 breaths/min = 4,200 mL/minute
The AVR is the most directly relevant to the body’s ability to get O2 to the tissues and to dispose of CO2.
