[Exam 2] Lecture 2 Flashcards
What is the thorax considered as a unit?
The whole thorax is considered one continuous, sealed unit.
This includes the heart and lung tissue.
What happens when half of the diaphragm is paralyzed?
The lung on the paralyzed side will likely sink, while the other lung may rise.
This is due to the contraction of the functioning half of the diaphragm.
Which lung is typically larger, the right or the left?
The right lung is typically larger than the left lung.
The left lung is smaller due to the space occupied by the heart.
What is the apex of the lung?
The apex of the lung is the highest point, which can extend past rib one and sometimes past the clavicle.
This is often higher than people commonly perceive.
What are the linings on the outside of the lungs called?
The linings are called pleura.
The visceral pleura coats the outside of the lungs, while the parietal pleura lines the inside of the thorax.
What are the two types of pleura associated with the lungs?
Visceral pleura and parietal pleura.
Visceral pleura is on the lungs, while parietal pleura is on the thoracic wall.
What can cause pain during a lung infection?
Pain can occur due to friction and inflammation in the lung tissue.
This happens when the tissues cannot slide smoothly due to infection.
How do the lungs expand during inspiration?
The diaphragm contracts and pulls down on the thoracic cavity, creating negative pressure that sucks air in.
This mechanism allows the lungs to fill with air.
What openings are present in the diaphragm?
Openings for the inferior vena cava, esophagus, and aorta.
These are essential for blood and food passage.
What is the central tendon in the diaphragm?
A large piece of connective tissue that serves as a platform for the heart.
It is not connected to bone but provides structural support.
What is the primary muscle of inspiration?
The diaphragm.
It is the main muscle used for ventilation.
What are accessory muscles in respiration?
Muscles that assist with ventilation during stress or exercise.
Examples include scalene muscles and intercostal muscles.
What is the term for normal breathing?
Eupnea.
It represents a state of normal respiratory function.
What does dyspnea refer to?
Respiratory distress or difficulty in breathing.
It indicates the sensation of not getting enough air.
What is the significance of the phrenic nerve?
It innervates the diaphragm and is crucial for breathing.
Damage to the phrenic nerve can severely affect respiratory function.
How many generations of airways are there in the respiratory system?
About 24 generations.
The trachea is generation zero, with bronchi branching into further generations.
What is the difference between conducting zones and respiratory zones?
Conducting zones do not involve gas exchange, while respiratory zones do.
Alveoli are part of the respiratory zone.
What is stridor?
A term for abnormal sounds produced during breathing.
It can be associated with conditions like asthma or lung tumors.
What does orthopnea describe?
Breathing difficulty when changing body position.
For example, difficulty breathing when lying down.
What is hyperventilation?
Rapid or excessive breathing.
It can occur during anxiety or panic attacks.
What does bradypnea refer to?
Slow breathing
What is tachypnea?
Rapid breathing
Define orthopnea.
Change in breathing when changing body position
What characterizes hyperpnea?
Fast, over-breathing
What is hyperventilation?
Ventilation exceeding metabolic demands
Hypoventilation is defined as _______.
Insufficient ventilation for metabolic demands
What does hyperinflation describe?
Lungs larger than normal, often seen in COPD
What is cyanosis?
Presence of deoxyhemoglobin causing a blue appearance
What is the technical definition for cyanosis?
5 g or greater deoxyhemoglobin in each deciliter of blood
Define hypoxia.
Not enough oxygen at the tissue level
What does hypoxemia describe?
Lower than normal oxygen in the entire system, specifically arterial blood
Hypercapnia refers to _______.
Excessive CO2 in blood
Define hypocapnia.
Lower than normal CO2 in blood
What is hyperoxia?
Greater than normal oxygen levels, typically tissue-specific
Atelectasis describes what condition?
Collapsed portion or region of a lung
What unit is used for thoracic pressures?
Centimeters of water (cm H20)
Why are centimeters of water used for thoracic pressures?
Provides greater resolution for low pressures
What does the term ‘content’ refer to in pulmonary contexts?
Total gas content in blood, including oxygen attached to hemoglobin and dissolved in solution
What does ‘PaO2’ stand for?
Pressure of dissolved oxygen in an arterial sample
What is ‘PAO2’?
PO2 in the alveolar gas
What does ‘V’ represent in pulmonary abbreviations?
Ventilation
Tidal Volume is abbreviated as _______.
VT
What is the volume of oxygen absorbed each minute abbreviated as?
VO2
Define compliance in a respiratory context.
Describes the stretchiness of lung tissue
What is elastance?
The inverse of compliance
What is the normal tidal volume for a healthy adult?
0.5 L
What is the Total Lung Capacity (TLC) for a healthy adult?
6 L
Functional Residual Capacity (FRC) is _______.
3 L in a normal person
What does FRC help stabilize?
Blood gases
What is the Expiratory Reserve Volume (ERV) in a healthy 20-year-old?
1.5 L
What is the expiratory reserve volume (ERV)?
1.5 L
ERV is the volume of air that can be forcibly exhaled after a normal tidal expiration.
What is the typical ERV for a healthy 20-year-old?
1.5 L
What does residual volume (RV) refer to?
Air that cannot be exhaled from the lungs, typically 1.5 L
RV is the volume of air remaining in the lungs after a forced exhalation.
What is the inspiratory reserve volume (IRV)?
2.5 L
IRV is the additional amount of air that can be inhaled after a normal tidal volume.
What is the total vital capacity of the lungs?
4.5 L
Vital capacity is the maximum amount of air that can be exhaled after a maximum inhalation.
How is vital capacity calculated?
ERV + IRV + Tidal Volume = 4.5 L
Tidal volume is typically 0.5 L.
What is the inspiratory capacity of the lungs?
3 L
Inspiratory capacity is the sum of IRV and tidal volume.
What is the normal tidal volume?
500 mL
True or False: The normal respiratory rate is 12 breaths per minute.
True
What are the phases of a normal respiratory cycle?
Inspiration (2 seconds), Expiration (2 seconds), Pause (1 second)
What is the normal thoracic pressure between breaths?
-4 mmHg or -5 cmH2O
What happens to thoracic pressure during inspiration?
It decreases, reaching -7.5 cmH2O at the end of inspiration.
Fill in the blank: The functional residual capacity (FRC) is composed of ______ and ______.
ERV and RV
What effect does body position have on expiratory reserve volume (ERV)?
It can decrease ERV due to the weight of the abdomen pushing up on the diaphragm.
What determines the airflow rate during inspiration?
The delta pressure (ΔP) between the alveolar pressure and environmental pressure.
What is the alveolar pressure during normal breathing?
0 cmH2O between breaths.
What does a negative alveolar pressure indicate?
Air is being sucked into the lungs.
What is the peak airflow rate during inspiration?
0.5 liters per second at the halfway point of inspiration.
How long does a complete respiratory cycle last?
5 seconds
In a healthy individual, what is the total lung capacity when fully inspired?
6 L
What is the primary function of the diaphragm during inhalation?
To lower thoracic pressure, facilitating air intake.
What happens to the pressure in the alveoli at the end of inspiration?
It equilibrates back to 0 cmH2O.
What happens to alveolar pressure during expiration?
Alveolar pressure becomes positive, pushing air out of the lungs.
This occurs as the diaphragm relaxes, increasing pleural pressure.
What is the abbreviation for tidal volume?
VT
Tidal volume refers to the amount of air inhaled or exhaled during normal breathing.
What does PIP stand for in respiratory physiology?
PIP stands for intra pleural pressure.
Sometimes also abbreviated as PPl.
What does the term transpulmonary pressure (PTP) refer to?
The difference in pressures between pleural pressure and alveolar pressure.
It is crucial for lung inflation.
What is the formula for describing blood flow in Zone 2 of the lungs?
Pa > PA > Pv
Where Pa is arterial pressure, PA is alveolar pressure, and Pv is venous pressure.
What characterizes blood flow in Zone 2 of the lungs?
Intermittent blood flow depending on pulmonary blood pressure.
Blood flow is present sometimes during the cardiac cycle.
What happens to blood flow in Zone 3 of the lungs?
There is continuous blood flow throughout the cardiac cycle.
This occurs because vascular pressures are higher at the base of the lung.
What conditions lead to Zone 1 blood flow in the lungs?
Alveolar pressure is higher than both arterial and venous pressures.
This results in no blood flow through the capillaries.
True or False: Zone 1 blood flow is common in healthy individuals.
False
Zone 1 is typically absent in healthy lungs.
What can cause Zone 1 blood flow during ventilation?
Positive pressure ventilation can compress blood vessels.
This leads to higher alveolar pressure and potential cessation of blood flow.
What is the relationship between transpulmonary pressure and pleural pressure?
Transpulmonary pressure is highly dependent on pleural pressure.
An increase in pleural pressure generally leads to a decrease in transpulmonary pressure.
What is the primary determinant of perfusion zones in the lungs?
Gravity
Gravity affects blood flow distribution within the lung zones.
What effect does increased gravitational pressure have on pulmonary blood vessels?
It stretches the blood vessels, leading to less resistance and more blood flow.
This is particularly evident in Zone 3.
Fill in the blank: Transpulmonary pressure is also known as _______.
Transmural pressure
It represents the pressure difference across the lung wall.
What happens to blood flow at the apex of the lungs in healthy individuals?
There is typically no blood flow due to low vascular pressures.
This area corresponds to Zone 1.
How does the body manage pulmonary perfusion during illness?
By routing blood flow away from unhealthy areas.
This is done to optimize gas exchange and maintain oxygenation.
What is the average blood flow through the lungs?
5 liters per minute.
Most of this flow occurs at the lower parts of the lung.
What happens to blood flow at the very base of the lung?
There is a little bit less blood flow due to the effect of gravity compressing the blood vessels.
This area is referred to as zone four.
What is zone four in the context of lung perfusion?
Zone four is an area at the base of the lung where blood flow is compressed due to gravity.
West identified four perfusion zones, while Levitsky does not include zone four.
Who proposed the concept of the four perfusion zones in the lungs?
West proposed the concept of the four perfusion zones.
Levitsky disagrees with this classification and does not include zone four in his textbook.
How does gravity affect blood flow in the lungs?
Gravity compresses the blood vessels, leading to reduced blood flow at the base of the lungs.
This phenomenon is particularly noted in zone four.
True or False: Levitsky includes zone four in his textbook.
False.
Levitsky chooses not to include zone four in his classification of lung perfusion zones.
Fill in the blank: The area of the lung with continuous blood flow but slightly less at the very base is called _______.
zone four
This zone is characterized by compression of blood vessels.
