PCP Expansion - Respiratory (A&P) Flashcards
What type of cell generates surfactant
Type II Pneumocytes
What does surfactant do?
Decreases surface tension to keep the alveoli open
CO2/O2 are carried across the blood gas barrier by what mechanism
Diffusion
What three groups of people are at risk of improper mucociliary clearance?
- Smokers
- Individuals with lung disease
- Exposure to pollutants and hazardous materials
What substances kills bacteria in the nasal pharynx?
Lysozymes
Why are smokers at risk of improper mucociliary clearance?
Smoking can increase the risk of impaired cilia, affecting cilia’s ability to clear debris from the lungs
Why are individuals with lung disease at risk of improper mucociliary clearance?
Individuals with lung diseases could encounter respiratory distress from dysfunctional cilia
Why does exposure to pollutants and hazmat materials increase risk of improper mucociliary clearance?
Cilia may not work effectively to eliminate harmful particles from exposure to pollutants and hazardous materials
What are the two parts of the pleura?
- Visceral (inner layer of the pleura)
- Parietal (outer layer of the pleura)
What fluid is between the visceral and parietal pleura?
Pleural fluid
Why is pleural fluid produced in the parietal pleura?
In the parietal pleura
What is the purpose of pleural fluid?
Pleural fluid reduces friction between the layers of the pleura for smooth movement during breathing, allowing for expansion and contraction of the lungs
If there is a decrease in surfactant, what is an action a Paramedic can do to keep the alveoli open?
Apply PEEP
How many alveoli are in the lungs?
Around 400-600 million
What four neurological groups control respiration?
- Ventral Respiratory Group
- Dorsal Respiratory Group
- Pneumotaxic Center
- Apneustic Center
What is the function of the Ventral Respiratory Group?
Primary responsible for forced inspiration and exhalation, particularly in situations where deeper breaths are needed
What is the function of the Dorsal Respiratory Group?
Neurons in the DRG stimulate the intercostal muscles and diaphragm to contract, promoting inhalation. These muscles are essential for breathing and are innervated by specific nerve fibers
What is the function of the Pneumotaxic Center?
Balances the respiratory process by inhibiting the DRG, allowing for relaxation and exhalation after inhalation
What is the function of the Apneustic Center?
Collaborates with the DRG to fine-tune the depth of inspiration, regulating how deeply one breathes
What three factors stimulate respiration?
- pH and Acidity
- Low oxygen
- Carbon Dioxide
Why does pH and acidity stimulate respiration?
Carbon dioxide levels in the blood influence the control of breathing, and this regulation is tied to the blood’s pH and acidity
Why does low oxygen stimulate respiration?
A stimulus for respiration is low levels of oxygen in the body. When oxygen levels drop, the body responds by increasing the intake of oxygen and inhaling
Why does carbon dioxide stimulate respiration?
The brain stem works together to balance the amount of oxygen and carbon dioxide in the blood, either taking in more oxygen or removing carbon dioxide. This also affects the pH and acidity of the blood.
What does FiO2 stand for? What does it mean?
Fraction of Inspired Oxygen
Indicates the percentages of inspired oxygen in inspired air
(e.g. 21% for room air)
What does SpO2 stand for? What does it mean?
Saturation of Peripheral Oxygen
Measures the percentage of oxygen saturated hemoglobin in the blood
(e.g. 95%)
What does SaO2 stand for? What does it mean?
Saturation of Arterial Oxygen
Measures the oxygen in arterial blood
(e.g. 95%)
What does PaO2 stand for? What does it mean?
Partial Pressure of Oxygen in Arterial Blood
Measures the pressure of oxygen dissolved in arterial blood
(millimeters of mercury)
What is the formula for minute volume
Minute Volume = Tidal Volume X Respiratory Rate
(Ve = Vt X RR)
Define Minute Volume (Ve)
Minute volume is the total volume of air that is moved into or out of the lungs in one minute
(e.g. 500 mL)
Define Tidal Volume (Vt)
Tidal volume refers to the volume of air that is inspired or expired with breath during normal breathing
(e.g. 500 mL)
Describe Inspiratory Reserve Volume (IRV)
Taking a deep breath
(i.e. exercise or whenever we need more oxygen)
Describe Residual Volume (RV)
Residual volume is the air that remains in our longs even after exhaling as much as possible. This volume is always present in our lungs, and we can’t completely exhale it.
Describe Expiratory Reserve Volume (ERV)
Expiratory reserve volume is extra air we can pushout of our lungs after a regular exhalation (when we forcefully exhale)
Describe Functional Residual Capacity (FRC)
Functional residual capacity is how effectively we oxygenate our bodies
When we breathe in and out with regular tidal volume breaths, there is always some air left in our lungs. Increasing the amount of oxygen in residual air can enhance oxygenations
PEEP or CPAP can be used to increase this capacity to improve oxygen levels
Describe Total Lung Capacity (TLC)
Adding all volumes together, total lung capacity is all the POSSIBLE volume of oxygen you can breathe in and out
Describe Vital Capacity (VC)
Vital capacity represents the difference between the maximum amount of air we can breathe in and the maximum we can exhale
Describe characteristics of obstructive lung disease
- Airflow obstruction
- Difficulty expelling air, leading to an “out” problem
- Characterized by small airways collapsing during exhalation
What conditions are associated with obstructive lung disease?
- Asthma
- COPD
- Cystic fibrosis
How some ways EMS can manage obstructive lung disease
- Salbutamol (Ventolin)
- Ipratropium bromide
(Atrovent) - CPAP
- EPINEPHrine
Describe characteristics of restrictive lung disease
- Airflow restriction
- Difficulty inhaling, causing an
“In” problem - Lungs may be stiff or
atelectatic (i.e. alveoli collapsed and cannot reopen)
What conditions are associated with restrictive lung disease?
- Pulmonary fibrosis
- Pneumonia
- Acute respiratory distress
syndrome (ARDS) - Obesity
How some ways EMS can manage restrictive lung disease
Treatment may involve the application of PEEP/CPAP to keep the lungs open.
What is Boyle’s Law?
The relationship between the pressure and volume of a gas in a closed system while keeping the temperature constant
When one increases, the other decreases proportionally
How does Boyle’s Law relate to aeromedical situations?
When moving a patient with conditions like pneumothorax, the decrease in cabin pressure at higher altitudes can cause an increase in the volume of trapped gas
How does Boyle’s Law relate to dive medicine situations?
When divers ascend rapidly, they risk conditions like pneumothorax. Such rapid ascents can cause trapped gas to expand, potentially worsening pneumothorax
What is Dalton’s Law?
Dalton’s Law describes the relationship between atmospheric pressure and the partial pressure of individual gases. That is the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of individual gases in the mixture
How does Dalton’s Law relate to medical situations
Atmospheric pressure is different at different altitudes. This affects the partial pressure of oxygen (PaO2) for patients in different locations even when the overall concentration of oxygen is the same
What is Fick’s Law?
Fick’s Law describes factors that affect the rate of diffusion across a membrane
What factors affect Fick’s Law?
- Concentration of oxygen
- Thickness of the membrane
- Surface area available for
diffusion
What could the need for home oxygen indicate?
- Asthma
- Emphysema
- Bronchitis
- Lung cancer
- Cystic fibrosis
- Congestive heart failure
When would someone require home oxygen?
- All the time (Resting O2) -
most common; resting O2
depends on the arterial
blood gas (ABG) and PaO2 - At night (Nocturnal O2)
- Sometimes (ambulatory O2)
List the benefits of CPAP
- Maintain alveoli open
- Improve diffusion (Fick’s
Law) - Decreased afterload (i.e.
extra pressure in the chest
can increase blood to the
bloodstream)
List the downsides of CPAP
- Decreased preload (i.e. extra
pressure in the chest can
decrease the amount of
blood flow to the heart) - Lower blood pressure
- Decreased SpO2
- Patient comfort/anxiety
from using the CPAP mask
