Lung disorders Flashcards
(202 cards)
1
Q
What term describes the maximum amount of air that can be exhaled after a maximum inhalation?
A
vital capacity
2
Q
Define the volume of air inhaled or exhaled with each breath under resting conditions.
A
tidal volume
3
Q
How do you calculate the inspiratory capacity?
A
Inspiratory capacity is calculated by adding the tidal volume and the inspiratory reserve volume together.
4
Q
What does functional residual capacity refer to?
A
Functional residual capacity is the volume of air remaining in the lungs after a normal, passive exhalation.
5
Q
Explain the significance of the residual volume in the lungs.
A
Residual volume is important because it prevents lung collapse by maintaining alveolar inflation.
6
Q
How is vital capacity related to total lung capacity?
A
Vital capacity is the total amount of air that can be exhaled after a full inhalation and is a portion of the total lung capacity minus the residual volume.
7
Q
Describe the difference between inspiratory reserve volume and expiratory reserve volume.
A
Inspiratory reserve volume is the additional air that can be inhaled with effort after a normal inhalation, whereas expiratory reserve volume is the additional air that can be forcibly exhaled after the end of a normal exhalation.
8
Q
What might an increase in residual volume indicate about lung function?
A
An increase in residual volume often indicates obstructive lung disease, where the emptying of the lungs is impaired.
9
Q
How can a spirometry test be useful in diagnosing respiratory conditions?
A
Spirometry can help measure lung volumes and flow rates, which are essential for diagnosing conditions like asthma, chronic obstructive pulmonary disease (COPD), and restrictive lung disease.
10
Q
what is coughing?
A
Coughing is a reflexive action of the body that serves as a protective mechanism for the lungs.
Protective Function: A cough is an explosive expiration that helps protect the lungs from aspiration of foreign materials. It also aids in the movement of secretions from the lower respiratory tract toward the mouth [where it can be swallowed or expectorated].
11
Q
what triggers innate cough reflex?
A
mucosa located between the larynx and the second-order bronchi. In some cases, stimulation of other areas, such as the ear canal due to cerumen (ear wax), or inflammation of the pleura (the membrane surrounding the lungs), can also trigger a cough.
12
Q
what are some common causes of cough?
A
Etiological Classification of Cough Causes:
Mechanical: Distortion of the airways, which may occur due to conditions like fibrosis (scarring of the lung tissue) or atelectasis (collapse of part of the lung).
Inflammatory: Inflammation of the trachea and bronchi, which can be caused by viral or bacterial infections, or by chronic inflammatory processes affecting the respiratory system.
Chemical: Inhalation of irritants such as smoke or dust can irritate the airways and trigger a cough reflex.
Drugs: Certain medications, particularly angiotensin-converting enzyme (ACE) inhibitors, which are commonly used to treat high blood pressure and heart failure, can cause a dry cough as a side effect.
Psychogenic: A dry cough can sometimes be related to psychological factors such as anxiety. While cough is generally a manifestation of an organic disease, stress and psychological factors can exacerbate a cough that has an organic cause.
13
Q
which trug tends to cause cough?
A
ACE inhibitors
14
Q
what is the process of cough reflex?
A
Rapid Inspiration:
The process begins with a deep and rapid inhalation, which draws air into the lungs.
Closure of the Glottis:
Following the inhalation, the glottis (the opening between the vocal cords in the larynx) closes abruptly to trap the air within the lungs.
Contraction of Expiratory Muscles:
Almost simultaneously, the muscles of the abdomen and thorax (including the diaphragm and the intercostal muscles) contract forcefully. This contraction increases the pressure inside the thoracic cavity.
Increase in Pressure:
The pressure within the pleural cavity (the thin fluid-filled space between the two pulmonary pleurae of each lung) and the lungs themselves (intrapulmonary pressure) rises sharply. This pressure can reach levels significantly higher than normal, often between 100 to 200 millimeters of mercury (mmHg).
Sudden Opening of the Glottis:
After a brief moment, the glottis opens suddenly, allowing the pressurized air in the lungs to be expelled rapidly.
Expulsion of Air:
A burst of air rushes out of the lungs, through the open glottis, and out of the mouth at high speed. This fast-moving air helps to dislodge and expel any irritant or foreign material from the airways.
15
Q
what does the pressure in the pleural cavity and lungs increase to during cough reflex?
A
This pressure can reach levels significantly higher than normal, often between 100 to 200 millimeters of mercury (mmHg).
16
Q
which part of the trachea invaginates and narrows the trachea during cough reflex and why?
A
the posterior non-cartilaginous part
The trachea has cartilaginous rings that provide structural support to prevent collapse. However, the posterior part of the trachea (the membranous part) does not have cartilage and is therefore more flexible. The high pressure generated during the cough can cause this part of the trachea to invaginate or fold inwards, narrowing the trachea’s lumen.
17
Q
The combination of high pressure and high-velocity airflow acts to do what during cough reflex?
A
dislodge and propel the material up the trachea and into the throat, from where it can be swallowed or expectorated.
18
Q
what is Bernoulli principle?
A
the principle of fluid dynamics (Bernoulli’s principle), when the velocity of a fluid (in this case, air) increases, its pressure decreases.
19
Q
where are the irritant receptors primarily located that contributes to cough reflex?
A
These receptors are primarily found in the larynx, trachea, and large bronchi but can also be present in the external auditory meatus (ear canal), diaphragm, pleura, and stomach.
20
Q
once irritant receptors are activated what do they send afferent sensory signals through to the cough center in the brain?
A
vagus nerve CNX
21
Q
where is the cough center located in brain that integrates signal inputs?
A
medulla oblongata
The cough center integrates the incoming signals and if the stimulus is sufficient, it triggers an efferent (motor) response. This center can also be influenced by higher brain functions, such as emotions and conscious control, which is why sometimes a cough can be voluntarily suppressed or exacerbated.
22
Q
why are we able to voluntarily suppress or exacerbate our cough?
A
This cough center can also be influenced by higher brain functions, such as emotions and conscious control, which is why sometimes a cough can be voluntarily suppressed or exacerbated.
23
Q
the efferent signals are sent out from the cough centers through which nerves?
A
The efferent signals are sent out from the cough center through the vagus, phrenic, and spinal motor nerves to the effector organs.
The efferent signals lead to a coordinated series of muscular actions: the glottis closes, the muscles of the chest wall, diaphragm, and abdomen contract to generate increased intra-thoracic pressure, and then the glottis suddenly opens, resulting in a rapid expulsion of air from the lungs. This high-speed air flow is what helps clear irritants from the airways.
24
Q
what structure that’s part of the innate defense mechanism of the respiratory tract moves the mucus up towards the pharynx to be swallowed or expectorated?
A
mucociliary escalator
25
What are some common symptoms associated with upper respiratory tract infections like sinusitis or nasopharyngitis?
Upper respiratory tract infections can lead to symptoms such as a sensation of needing to clear the throat, postnasal drip, and following an upper respiratory syndrome or sinus symptoms.
26
How does tracheobronchitis typically present itself symptomatically?
Tracheobronchitis is associated with a sore throat, running nose, and eye irritation.
27
What differentiates bronchopneumonia from acute bronchitis?
Bronchopneumonia, which is usually dry or productive, begins as acute bronchitis but can become purulent, indicating an infection.
28
In the context of respiratory illnesses, what characterizes the exacerbation of chronic bronchitis?
An exacerbation of chronic bronchitis is indicated by the production of mucoid sputum becoming purulent.
29
How is chronic bronchitis defined in terms of duration and sputum production?
Chronic bronchitis is defined by the production of sputum on most days for more than three consecutive months in a year, for more than two years.
30
What are some distinct features of tuberculosis or fungal respiratory infections?
Tuberculosis or fungal respiratory infections are persistent for weeks to months, often with blood-tinged sputum.
31
Describe the nature of the cough associated with interstitial fibrosis and infiltrations.
Interstitial fibrosis and infiltrations usually cause a nonproductive, persistent cough, which depends on the origin of the condition.
32
How might adenocarcinoma in situ or minimally invasive lung cancer affect sputum production?
Adenocarcinoma in situ or minimally invasive lung cancer typically presents similarly to bronchogenic carcinoma, with occasional instances of large quantities of watery, mucoid sputum.
33
What symptom is often associated with mediastinal tumors due to their location?
Mediastinal tumors often cause breathlessness due to compression of the trachea and bronchi.
34
What cough symptom can be indicative of a foreign body in the airway?
A foreign body in the airway can cause a cough with immediate signs of asphyxiation if still in the upper airway, or a nonproductive, persistent cough with a localizing wheeze if in the lower airway.
35
How can left ventricular failure affect cough, especially when lying down?
Left ventricular failure can intensify coughing while lying supine, along with the aggravation of dyspnea.
36
what is the hallmark sign of croup?
A loud metallic barking cough
37
what is croup?
an infection that leads to swelling around the vocal cords (larynx), windpipe (trachea), and bronchial tubes (bronchi).
38
what are some causes for the loud barking cough heard in croup?
Subglottic Edema: The term "subglottic" refers to the area just below the vocal cords. When this region becomes swollen due to inflammation, it narrows the airway.
Non-Productive Cough: The cough associated with croup does not typically produce mucus or sputum, hence it's described as "non-productive."
'Metallic' Quality: The cough is often described as having a metallic sound because the airflow through the narrowed, inflamed subglottic area produces a unique resonating sound.
Occurrence in Children: Croup is most common in children. Their airways are smaller and more susceptible to becoming obstructed when swelling occurs.
Acute Bacterial or Viral Laryngotracheitis: Croup can be caused by a viral infection (most commonly the parainfluenza virus) or, less frequently, by a bacterial infection. Laryngotracheitis refers to inflammation of the larynx and trachea.
Inspiratory Stridor: This is a high-pitched, wheezing sound made when a child breathes in. It is another indication of the narrowed airway and is often more noticeable when the child is crying or agitated.
Respiratory Distress: The child may show signs of difficulty breathing, such as fast breathing, the use of accessory muscles (neck, chest, and abdominal muscles), and retractions (skin pulling in around the ribs with each breath).
39
what are signs of respiratory distress in a child with croup?
The child may show signs of difficulty breathing, such as fast breathing, the use of accessory muscles (neck, chest, and abdominal muscles), and retractions (skin pulling in around the ribs with each breath).
40
croup is caused more by viral infection than by bacterial infection, which virus is it mainly caused by?
parainfluenza virus
Acute Bacterial or Viral Laryngotracheitis: Croup can be caused by a viral infection (most commonly the parainfluenza virus) or, less frequently, by a bacterial infection. Laryngotracheitis refers to inflammation of the larynx and trachea.
41
what signs are croup often accompanied with?
inspiratory stridor and respiratory distress
42
what is inspiratory stridor?
This is a high-pitched, wheezing sound made when a child breathes in. It is another indication of the narrowed airway and is often more noticeable when the child is crying or agitated.
43
when is inspiratory stridor most noticeable in a child with croup?
agitated or crying
44
why is croup more common in children?
Croup is most common in children. Their airways are smaller and more susceptible to becoming obstructed when swelling occurs.
45
what are some things that can impair cough reflex?
Damage to Irritant Receptors: Irritant receptors in the airways can be damaged by conditions like bronchiectasis, which involves chronic inflammation and dilatation of the bronchi. Furthermore, narcotics and anesthetics can reduce the sensitivity of these receptors, making them less responsive to irritants.
Neurological Disease: Diseases that affect the nervous system can damage the neural pathways responsible for the cough reflex, which can include peripheral nerves or centers in the central nervous system (CNS).
Tracheostomy Effects: A tracheostomy, which is a surgical procedure to create an opening in the trachea, bypasses the normal upper airway structures. This eliminates the closure of the glottis, which is crucial for generating the high-pressure gradient needed for an effective cough, thus decreasing peak intrapulmonary pressures.
Respiratory Muscle Weakness: Illness, aging, or neuromuscular diseases can weaken the respiratory muscles. This weakness can prevent the generation of sufficient pressure for an effective cough.
46
to impair cough reflex, what part must be affected?
Interrupting or blunting any step in the sequence may impair the cough reflex.
47
what's the minimum expiratory pressure you must be able to achieve in order to produce peak flow for an effective cough?
>60 cm of water
An effective cough requires the ability to generate high expiratory pressures. If a patient can achieve expiratory pressures greater than 60 cm H2O, they are typically able to produce a peak flow that will result in an effective cough.
48
what are 2 conditions that can damage irritant receptors?
bronchiectasis and narcotics/anesthetics
49
what is equal pressure point (EPP)?
The EPP is a theoretical point in the airways where the pressure inside the airway equals the pressure outside the airway in the surrounding tissue. During a cough, the location of this point is crucial for determining which parts of the airway can effectively clear secretions.
50
when the lung volume is high, where is the equal pressure point (EPP) located?
the larger airways
When the lung volume is high, the EPP is located in the larger airways. This is because the larger airways are held open by the higher surrounding pressure due to the inflated lungs. A cough at this volume can generate a high-velocity airflow from deep within the lungs, which helps to move secretions from the smaller airways into the larger ones where they can be more easily expelled ("downstream").
51
when the lung volume is decreased where is the equal pressure point (EPP) located?
closer to alveoli
As lung volume decreases, such as after several coughs without an intervening breath, the EPP moves "upstream" closer to the alveoli. At lower lung volumes, the airway pressure can fall below the pressure of the surrounding tissue, causing smaller airways to collapse. This collapse can trap secretions in the small airways and alveoli.
52
why can repeatedly coughing without taking breaths hinder clearance of secretions?
It prevents reinflation of lungs and allows small airway collapse
If a person coughs repeatedly without taking a breath in between, the EPP moves progressively closer to the alveoli with each cough. This is beneficial because it helps clear particles from the deeper parts of the lungs. However, it is also important to have intervening inspirations to re-inflate the lungs and prevent small airway collapse, which can hinder the clearance of secretions.
53
for cough to be most effective it should occur at what lung volume and where should the EPP be located?
For a cough to be most effective, it should occur at a relatively high lung volume to ensure that the EPP is in the larger airways and to maximize airflow velocity, thereby helping to clear secretions from the lower respiratory tract.
54
what are the consequences of increased thoracic pressure in the body for cough?
Rise in Vascular Pressures: The increase in intrathoracic pressure causes a corresponding increase in the pressure within the vessels, including blood vessels and the cerebrospinal fluid (CSF). This pressure change is transmitted evenly and does not typically alter the pressures on the coronary vessels, lungs, or other organs significantly, hence typically there are no direct clinical consequences on these structures from the pressure change alone.
Reflex Vasodilation: The body responds to the rise in intrathoracic pressure with a reflex that causes the systemic arteries and veins to dilate. This reflex vasodilation is likely a compensatory mechanism to maintain adequate cardiac output despite the increased pressure.
Decrease in Cardiac Output and Venous Return: Vasodilation of the vessels can reduce the amount of blood returning to the heart (venous return), which in turn can decrease cardiac output. Cardiac output is the volume of blood the heart pumps per minute, and it is determined by the stroke volume (the amount of blood pumped with each beat) multiplied by the heart rate.
Potential for Syncope: In patients with cor pulmonale (right-sided heart disease caused by lung disease) and right heart failure, these changes in pressure and cardiac output can be critical. These patients have a compromised ability to compensate for fluctuations in pressure and blood flow. As a result, a significant decrease in cardiac output can lead to syncope (fainting) due to inadequate perfusion of the brain.
55
why might Vasodilation leads to a decrease in cardiac output and then a decrease in venous return when intrathoracic pressure has increased for cough?
Decrease in Cardiac Output and Venous Return: Vasodilation of the vessels can reduce the amount of blood returning to the heart (venous return), which in turn can decrease cardiac output. Cardiac output is the volume of blood the heart pumps per minute, and it is determined by the stroke volume (the amount of blood pumped with each beat) multiplied by the heart rate.
56
why might people with cor pulmonale or right heart failure encounter syncope during increased thoracic pressure for cough?
Potential for Syncope: In patients with cor pulmonale (right-sided heart disease caused by lung disease) and right heart failure, these changes in pressure and cardiac output can be critical. These patients have a compromised ability to compensate for fluctuations in pressure and blood flow. As a result, a significant decrease in cardiac output can lead to syncope (fainting) due to inadequate perfusion of the brain.
57
which gender experience cough syncope more and why?
Men may be more prone to cough syncope because they can typically generate higher intrathoracic pressures compared to women. This greater pressure can lead to a more significant decrease in cardiac output.
58
what condition does cough syncope resemble and how do you differentiate the 2?
It is crucial to distinguish cough syncope from epileptic seizures, as the two can appear similar. In the past, cough syncope was sometimes considered a form of epilepsy, but they are now recognized as distinct conditions. Epileptic seizures are neurological events caused by abnormal electrical discharges in the brain, while cough syncope is a circulatory issue.
epilepsy need to be ruled out
59
what is the probable cause of post-tussive cough?
person coughs more forcefully and longer than average person affecting circulatory system.
60
what are causes of dyspnea?
Dyspnea can be due to issues in the respiratory system such as asthma, COPD, pneumonia, or pulmonary fibrosis. Cardiac conditions like heart failure or myocardial infarction can also cause dyspnea. Other causes include neuromuscular disorders that affect the muscles involved in breathing, psychogenic causes such as anxiety, or systemic illnesses like anemia or metabolic acidosis. Often, these causes can overlap.
61
what is air hunger?
desperate feeling of being unable to breathe sufficiently, sometimes accompanied by panic.
62
how do you describe acute dyspnea?
Acute dyspnea develops over a short time, typically hours to days, and is often more alarming to the patient. It may signal an urgent medical condition.
63
how do you describe chronic dyspnea and what is it usually due to?
Chronic dyspnea persists over a longer period, usually defined as more than 4 to 8 weeks, and can be due to ongoing medical conditions like COPD or chronic heart failure.
64
what is the pathway of sensation of breathlessness?
Sensory Input: Signals from the body are sent to the brain regarding the state of the airways, lungs, respiratory muscles, and the chest wall. This includes input from mechanoreceptors in the respiratory tract and chemoreceptors that respond to changes in blood gases.
Motor Cortex: Signals for respiratory effort originate here and are sent to the ventilatory muscles.
Brain Stem: This area regulates the automatic aspects of breathing and contributes to the sensation of air hunger, which is the uncomfortable feeling of not getting enough air.
Vagal Stimulation: The vagus nerve, which innervates the lungs, sends signals when irritant receptors are stimulated, contributing to the sensation of chest tightness.
65
what causes air hunger?
Air Hunger: This perception arises from increased respiratory activity within the brain stem.
66
what are some respiratory causes of dyspnea?
Respiratory Causes:
Conditions that obstruct air flow (e.g., asthma, COPD).
Infections that impair gas exchange (e.g., pneumonia).
Blockages in the pulmonary blood vessels (e.g., pulmonary embolism).
Diseases affecting lung tissue and its ability to expand (e.g., lung malignancy, pneumothorax).
Inhaled foreign objects causing obstruction (aspiration).
67
what are some cardiovascular causes of dyspnea?
Cardiovascular Causes:
Heart conditions that prevent proper circulation (e.g., congestive heart failure, valvular heart defects).
Increased pressure in the pulmonary circulation (pulmonary hypertension).
Conditions that affect the heart's rhythm (cardiac arrhythmia).
Abnormal connections between the heart chambers (intracardiac shunting).
Accumulation of fluid in the lung tissue (pulmonary edema).
Compression of the heart by fluid in the pericardium (pericardial tamponade).
68
what are some neuromuscular causes of dyspnea?
Neuromuscular Causes:
Physical trauma to the chest wall or spinal injuries.
Diseases affecting the muscles and nerves involved in respiration (myopathy, neuropathy, phrenic nerve paralysis).
Structural deformities that impair lung function (kyphoscoliosis).
Excessive body weight increasing the work of breathing (obesity).
69
what are some psychogenic causes of dyspnea?
Psychogenic Causes:
Conditions where emotional or psychological factors lead to the sensation of breathlessness (hyperventilation syndrome, psychogenic dyspnea).
Dysfunctions of the vocal cords that can mimic respiratory conditions (vocal cord dysfunction syndrome).
70
what are some systemic causes of dyspnea?
Systemic Illnesses:
Conditions affecting the body's oxygen-carrying capacity (anemia).
Metabolic disturbances that can lead to increased breathing rate (metabolic acidosis).
Endocrine disorders that accelerate metabolism (thyrotoxicosis).
Severe allergic reactions or infections causing systemic responses (anaphylaxis, sepsis).
Swelling in the airways (angioedema) or inflammation of the epiglottis (epiglottitis).
71
What are two acute conditions that can cause dyspnea due to a rapid accumulation of fluid in the lungs?
Acute pulmonary edema and adult respiratory distress syndrome (ARDS) can both cause rapid fluid accumulation in the lungs, leading to acute dyspnea.
72
Name a chronic condition that can progressively lead to dyspnea by causing obstruction of the airways.
Chronic obstructive pulmonary disease (COPD) is a chronic condition that can cause airway obstruction and progressive dyspnea.
73
Which acute event can cause dyspnea by disrupting the integrity of the lung’s pleural space?
A spontaneous pneumothorax, which is the sudden presence of air in the pleural space, can disrupt normal lung function and cause acute dyspnea.
74
How can a condition affecting the heart lead to chronic symptoms of dyspnea?
Left ventricular failure can lead to chronic dyspnea due to the back-up of fluid into the lungs, a condition known as congestive heart failure.
75
What is a potential psychogenic cause of dyspnea and how does it manifest?
Psychogenic dyspnea, which is often related to anxiety, can manifest as a sensation of breathlessness or suffocation without an organic cause.
76
Identify a blood condition that can cause chronic dyspnea and explain why it affects breathing.
Severe anemia can lead to chronic dyspnea because the reduced number of red blood cells limits oxygen transport to tissues, prompting increased breathing to meet oxygen demands.
77
which condition that can cause dyspnea can be considered as both acute and chronic?
asthma
78
what is it called when there is a mismatch between the effort of breathing and the actual movement of air, perceived by the respiratory center in the brainstem. Essentially, the brain registers that despite efforts to breathe, not enough air movement (effective ventilation) is occurring?
Respiratory System Neuromechanical Dissociation
79
what is it called when Dyspnea arise when the efferent (motor) neurological signals that regulate tidal volume (the amount of air moved into and out of the lungs with each breath) and respiratory rate do not achieve the expected mechanical results. This discrepancy is sensed through feedback from airflow and chest expansion and can cause the sensation of breathlessness?
Efferent Neurologic Output Failure
80
what can lead to extreme dyspnea?
When the neuromechanical dissociation is combined with a strong ventilatory stimulus such as hypercarbia (high carbon dioxide levels in the blood), metabolic acidosis, or hypoxemia (low blood oxygen levels), it can lead to extreme dyspnea.
81
what part of the brain is involved in emotional processing and can also cause the perception of dyspnea?
amygdala
This (amygdala activation) can occur in the absence of physical exertion/exercise
82
what conditions is primary amygdala activation seen in?
often seen in conditions like anxiety, depression, PTSD, and panic disorder.
83
what is is a feedback mechanism to prevent overexertion, which could exacerbate an underlying condition or risk further metabolic disturbance?
Exercise-Induced Dyspnea
When dyspnea is generated by the cardiovascular system or respiratory system, or in response to acidosis, it often functions as a protective mechanism to signal the body to cease exercise.
84
what can sometimes manifest as dyspnea. This occurs because the heart muscle may not be receiving enough oxygen, especially during exercise, and the body perceives this as a need to breathe more deeply or rapidly. This is a form of cardiac dyspnea where the heart's demand for oxygen exceeds the supply, similar to how angina functions as a warning sign to stop activity and reduce oxygen demand on the heart?
Angina
85
what are sensors located in the walls of cardiac chambers and large blood vessels that detect changes in blood pressure?
baroreceptors
When these chambers or vessels stretch due to increased pressure, as in the case of heart failure or when the heart's workload is increased (afterload), these receptors are activated. The reflexive response to this activation is to reduce the heart's workload, which can include terminating physical activity to lower cardiovascular pressure and, by extension, reduce the sensation of dyspnea.
86
what condition is the accumulation of fluid in the lungs due to heart problems, such as left ventricular failure?
Cardiogenic Pulmonary Edema
When the left side of the heart cannot pump blood effectively, pressure can build up in the pulmonary circulation, leading to fluid leaking into the lung tissue. This fluid reduces pulmonary compliance, meaning the lungs become stiffer and less able to expand. As a result, the work of breathing increases significantly, causing severe dyspnea. Additionally, the mismatch between the brain's respiratory center sending signals to breathe and the mechanical inability of the lungs to do so efficiently leads to what is termed neuromechanical dissociation.
87
what is reduced pulmonary compliance and what causes it?
When the left side of the heart cannot pump blood effectively, pressure can build up in the pulmonary circulation, leading to fluid leaking into the lung tissue. This fluid reduces pulmonary compliance, meaning the lungs become stiffer and less able to expand. As a result, the work of breathing increases significantly, causing severe dyspnea.
88
what type of blood gas changes stimulate dyspnea?
Ventilatory Stimulus: Changes in blood gases such as increased carbon dioxide (CO2), decreased oxygen (O2), or decreased pH can stimulate the body to breathe more deeply or frequently, leading to the sensation of dyspnea.
89
how does acidosis cause dyspnea?
Acidosis: Various types of acidosis, such as lactic acidosis or ketoacidosis, cause an increase in CO2 in the blood, which can also stimulate the respiratory centers in the brain and lead to dyspnea.
90
what is hemoptysis?
Hemoptysis is the coughing up of blood or bloody mucus from the lower respiratory tract (lungs and bronchi) [below vocal cords].
91
life threatening hemoptysis involves bleeding from which artery?
Life-threatening hemoptysis usually involves bleeding from the bronchial arteries, which are part of a high-pressure system and can lead to significant blood loss. This accounts for about 90% of severe cases.
92
nonlife threatening hemoptysis involves bleeding from which arteries?
In most cases, the bleeding originates from the pulmonary circulation, which is a low-pressure system. This often results in non-life-threatening bleeding.
93
in developed countries what are common causes of hemoptysis?
In developed countries, the most common causes of hemoptysis are acute bronchitis, bronchial neoplasms (tumors), and bronchiectasis (chronic dilation and inflammation of the bronchi).
94
in developING countries what are common causes of hemoptysis?
In developing countries, tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis, and parasitic infections like those from Paragonimus westermani (lung fluke) are prevalent causes.
95
where do most cases of nonlife threatening hemoptysis originate from?
originate from the pulmonary artery circulation. (low pressure system).
96
what is the difference between pulmonary circulation and bronchial circulation?
one sends deoxigenated blood from heart to be oxygenated while the other sends blood to oxygenate the lung tissue itself.
Pulmonary Circulation: The pulmonary arteries, which are large blood vessels, originate from the right ventricle of the heart. They carry deoxygenated blood to the lungs where gas exchange occurs. The blood releases carbon dioxide and receives oxygen before returning to the left atrium of the heart through the pulmonary veins.
Bronchial Circulation: In addition to the pulmonary circulation, the lungs also receive blood from the bronchial arteries. These arteries provide oxygenated blood to the lung tissue itself, nourishing the bronchi, bronchioles, and other supportive structures in the lungs. This system is part of the systemic circulation.
97
where does the right and left bronchial arteries arise from?
right one comes from right intercostal arteries while 2 left ones come directly from aorta having 2 separate origin points on aorta.
The right bronchial artery typically arises from an intercostal artery, which is a vessel that supplies blood to the muscles and other structures between the ribs.
On the left side, there are usually two bronchial arteries with separate origins arising directly from the aorta, the main artery that carries oxygenated blood from the left ventricle to the rest of the body.
98
how much bronchial arteries are on the left vs right?
2 and 1
99
What are two airway diseases that can cause hemoptysis?
Bronchitis and bronchiectasis are two airway diseases that can cause hemoptysis.
100
Name a pulmonary parenchymal disease and an infection that can lead to coughing up blood.
Rheumatic disease and tuberculosis are examples of a pulmonary parenchymal disease and an infection, respectively, that can lead to hemoptysis.
101
Which type of heart failure is a common cause of hemoptysis?
Congestive heart failure is a common cardiac cause of hemoptysis.
102
What are two bleeding disorders that can present with hemoptysis?
Disseminated intravascular coagulation (DIC) and thrombocytopenia are two bleeding disorders that can present with hemoptysis.
103
How can trauma lead to hemoptysis?
Trauma, such as external blunt or penetrating trauma to the chest, can damage the airways or lungs, leading to hemoptysis.
104
List a drug and a toxin that could cause coughing up blood.
Cocaine use and argemone alkaloid-contaminated cooking oil (as seen in epidemic dropsy) are examples of a drug and a toxin that could cause coughing up blood.
105
What is pseudohemoptysis and what might cause it?
Pseudohemoptysis refers to the expectoration of blood that is not from the lungs or bronchial tubes but instead from aspirated blood from the upper airway or gastrointestinal sources, such as from a nosebleed or gastrointestinal bleeding.
106
what is a Class of lung disorder characterized by increased resistance (obstruction) to the outflow of air from the lungs. Can result from inflammation of the airway or destruction of the alveoli?
obstructive lung disease
107
what are some common obstructive lung disease conditions?
Asthma: A chronic inflammatory disease of the airways that causes periodic episodes of airway constriction, resulting in wheezing and shortness of breath.
Chronic Bronchitis: Long-term inflammation of the bronchi, characterized by cough and mucus production for at least three months in a year for two consecutive years.
Emphysema: A disease that destroys the walls of the alveoli, leading to a reduced surface area for gas exchange and increased difficulty in breathing out.
Bronchiectasis: Chronic condition where the walls of the bronchi are thickened from inflammation and infection.
108
In pulmonary functions test (eg. spirometry), what happens to FEV1/FVC Ratio in obstructive lung disease?
decreases
FEV1: Forced Expiratory Volume in one second, the amount of air a person can forcefully exhale in one second.
FVC: Forced Vital Capacity, the total amount of air exhaled during the spirometry test.
↓ FEV1/FVC Ratio: In obstructive lung disease, this ratio is reduced because the FEV1 is disproportionately decreased compared to the FVC. This is indicative of the difficulty in expelling air out of the lungs.
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how do you differentiate restrictive lung disease from obstructive lung disease?
In restrictive lung diseases, both FEV1 and FVC are reduced proportionally due to a decreased ability to expand the lungs fully, but the FEV1/FVC ratio typically remains normal or may even increase.
In obstructive lung disease the ratio is decreased because FEV1 decrease a lot more than FVC
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what is the normal FEV1/FVC ratio percentage in healthy adult?
In healthy adults, the FEV1/FVC ratio is typically above 70-75% of the expected value based on age, sex, height, and race.
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what indicates that airflow limitation is not reversible in COPD related to PFT?
In COPD, this ratio is often less than 70% after the use of a bronchodilator, which indicates airflow limitation that is not fully reversible.
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what indicates airflow limitation is reversible and is more likely due to asthma than COPD related to PFT?
If there is a greater than 12% and 200 mL increase in FEV1 after administration of a bronchodilator, the airflow limitation is considered reversible. This suggests a significant bronchodilator response, which is more characteristic of asthma than COPD.
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What are the primary symptoms of a 'Blue Bloater'?
The primary symptoms of a 'Blue Bloater' include chronic productive cough, purulent sputum, hemoptysis, mild dyspnea initially, cyanosis due to hypoxemia, peripheral edema from cor pulmonale, crackles, wheezes, prolonged expiration, and obesity.
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What complication is a 'Blue Bloater' at risk of due to hypoxemia?
A 'Blue Bloater' is at risk of secondary polycythemia vera due to chronic hypoxemia. This is the body's compensatory response to increase oxygen-carrying capacity by producing more red blood cells.
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Describe the breathing pattern often observed in a 'Pink Puffer'.
A 'Pink Puffer' often exhibits pursed-lip breathing, which helps to increase airway pressure and prevent airway collapse during expiration.
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What physical sign indicates that a 'Pink Puffer' may have emphysema?
Hyperinflation or a barrel chest is a physical sign that indicates a 'Pink Puffer' may have emphysema. This occurs due to the destruction of alveolar walls and loss of elastic recoil in the lungs.
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What is the main characteristic that differentiates a 'Pink Puffer' from a 'Blue Bloater' in terms of physical appearance?
The main characteristic that differentiates a 'Pink Puffer' from a 'Blue Bloater' is the presence of cachexia and the lack of significant cyanosis in 'Pink Puffers,' as they tend to maintain better oxygenation despite their lung disease.
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what is cachexia?
A general state of ill health involving marked weight loss and muscle loss.
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What serious complication is a 'Pink Puffer' at risk of due to the nature of their lung disease?
A 'Pink Puffer' is at risk of pneumothorax due to the presence of bullae, which are large air-filled spaces that can rupture and cause the lung to collapse.
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How is chronic bronchitis clinically diagnosed?
Chronic bronchitis is clinically diagnosed by a daily productive cough that lasts for three months or more in at least two consecutive years.
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What are the characteristic symptoms of chronic bronchitis?
Characteristic symptoms of chronic bronchitis include being overweight and cyanotic, elevated hemoglobin levels, peripheral edema, and the presence of rhonchi and wheezing in the lungs.
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What is the pathologic diagnosis of emphysema?
The pathologic diagnosis of emphysema involves permanent enlargement and destruction of airspaces distal to the terminal bronchiole.
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What are the typical physical characteristics of a patient with emphysema?
Patients with emphysema are often older, thin, and present with severe dyspnea and a quiet chest upon examination.
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How does the chest X-ray of a patient with emphysema typically appear?
The chest X-ray of an emphysema patient usually shows hyperinflation with flattened diaphragms due to the overdistention of airspaces in the lungs.
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what is wheezing?
Wheezing is a common symptom of various respiratory conditions and is characterized by a high-pitched whistling sound that occurs during exhalation. The pathogenesis of wheezing involves the narrowing of airways and can be caused by several mechanisms, including those found in emphysema, bronchitis, and asthma
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which phase of respiration is wheezing heard?
expiration
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what are 3 conditions that cause wheezing?
The pathogenesis of wheezing involves the narrowing of airways and can be caused by several mechanisms, including those found in emphysema, bronchitis, and asthma
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how does wheezing develop?
Intrapleural Pressure: During exhalation, the intrapleural pressure increases as the thoracic cavity contracts to expel air from the lungs. Normally, this pressure is greater than the pressure inside the airways.
Airway Compression: If the intrapleural pressure exceeds the pressure within the airways, it can lead to airway compression. However, the connective tissue fibers within the airway walls usually provide enough structural support to prevent collapse.
Emphysema: In emphysema, there is destruction of the connective tissue fibers within the lungs, particularly the elastic fibers. This destruction leads to a loss of structural support and elastic recoil, causing the airways to collapse during exhalation, which contributes to the obstruction and results in wheezing.
Inflammatory Edema in Bronchitis: Chronic bronchitis is characterized by inflammation of the airway walls, leading to swelling (edema) and increased mucus production. This inflammation and mucus can narrow the airways, contributing to the wheezing sound, particularly during exhalation when the airway diameter is naturally reduced.
Bronchoconstriction in Asthma: Asthma involves hyperreactivity of the airways leading to bronchoconstriction, where the smooth muscles surrounding the airways tighten and reduce the diameter of the airways. This constriction, along with inflammation and mucus production, further narrows the airways, causing wheezing.
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how is wheezing developed in emphysema?
Emphysema: In emphysema, there is destruction of the connective tissue fibers within the lungs, particularly the elastic fibers. This destruction leads to a loss of structural support and elastic recoil, causing the airways to collapse during exhalation, which contributes to the obstruction and results in wheezing.
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how is wheezing developed in bronchitis?
Inflammatory Edema in Bronchitis: Chronic bronchitis is characterized by inflammation of the airway walls, leading to swelling (edema) and increased mucus production. This inflammation and mucus can narrow the airways, contributing to the wheezing sound, particularly during exhalation when the airway diameter is naturally reduced.
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how is wheezing developed in asthma?
Bronchoconstriction in Asthma: Asthma involves hyperreactivity of the airways leading to bronchoconstriction, where the smooth muscles surrounding the airways tighten and reduce the diameter of the airways. This constriction, along with inflammation and mucus production, further narrows the airways, causing wheezing.
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what are some changes that happen as obstructive lung disease develop?
Obstruction of airways leads to ↑ trapped air in the lungs which results in ↑ residual volume (RV), ↑ total lung capacity (TLC), ↑ functional reserve capacity (FRC), and ↓ in FVC.
V/Q mismatch
Increased physiologic dead space results in ↓ ventilation and V/Q mismatch (quantified as ↑ in the alveolar-arterial gradient (A-a gradient) and ↓ PaO2.
Airflow Obstruction: In obstructive lung diseases, the airways become narrowed, which can be due to inflammation, mucous plugging, structural changes, or a combination of these factors. This results in an increased resistance to airflow, especially during exhalation.
Lung Volumes and Capacities:
Increased Residual Volume (RV): Due to the obstruction, patients cannot fully exhale, leading to an increase in the amount of air that remains in the lungs after a full exhalation.
Increased Total Lung Capacity (TLC): As the disease progresses, the lungs may become overinflated with air, increasing the TLC.
Increased Functional Reserve Capacity (FRC): This is the volume of air present in the lungs at the end of a normal, passive exhalation, which increases due to air trapping.
Decreased Forced Vital Capacity (FVC): The amount of air that can be forcibly exhaled from the lungs after taking the deepest breath possible is reduced.
V/Q Mismatch: The ventilation-perfusion (V/Q) mismatch occurs when ventilation (airflow) and perfusion (blood flow) are not properly matched. This can happen when parts of the lung receive oxygen but not enough blood to exchange gases (ventilation without perfusion) or vice versa.
Increased Physiologic Dead Space: The parts of the lungs that do not contribute to gas exchange effectively are referred to as dead space. In obstructive lung disease, the increased dead space results from the collapse of small airways and destruction of alveolar walls, leading to poor ventilation.
Altered Gas Exchange:
Increased Alveolar-arterial (A-a) Gradient: This represents the difference in the oxygen concentration between the alveoli and the arterial blood, indicating impaired oxygen transfer from the lungs to the blood.
Decreased Partial Pressure of Oxygen (PaO2): This is a measure of the effectiveness of the lungs in oxygenating the blood.
Chronic Inflammation and Structural Changes:
Mucous Gland Enlargement and Hypersecretion: Leads to increased mucus production, which can obstruct the airways.
Ciliary Dysfunction: Impairs the ability to clear mucus and debris from the airways.
Squamous Metaplasia: Represents a change in the type of cells lining the airways, which can affect the airway's function.
Alveolar Wall Destruction (Emphysema): The destruction of alveolar walls leads to the permanent enlargement of air spaces and reduces the lung's surface area for gas exchange.
Airway Collapse During Expiration: Loss of alveolar walls reduces the support for small airways, causing them to collapse during expiration, further obstructing airflow and leading to air trapping.
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what narrows the airway in obstructive lung disease and increases resistance?
In obstructive lung diseases, the airways become narrowed, which can be due to inflammation, mucous plugging, structural changes, or a combination of these factors. This results in an increased resistance to airflow, especially during exhalation.
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what is residual volume?
the amount of air that remains in the lungs after a full exhalation.
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why is residual volume increase in obstructive lung disease?
Due to the obstruction, patients cannot fully exhale, leading to an increase in the amount of air that remains in the lungs after a full exhalation.
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why is total lung capacity increase in obstructive lung disease?
As the disease progresses, the lungs may become overinflated with air, increasing the TLC.
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what is functional reserve capacity?
volume of air present in the lungs at the end of a normal, passive exhalation
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why is functional reserve capacity increased in obstructive lung disease?
This is the volume of air present in the lungs at the end of a normal, passive exhalation, which increases due to air trapping.
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what is forced vital capacity?
The amount of air that can be forcibly exhaled from the lungs after taking the deepest breath possible...it's decreased in obstructive lung disease.
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what is total lung capacity?
the volume of air in the lungs upon the maximum effort of inspiration.
assesses restrictive lung disease
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what is physiological dead space and why is it increased in obstructive lung disease?
The parts of the lungs that do not contribute to gas exchange effectively are referred to as dead space. In obstructive lung disease, the increased dead space results from the collapse of small airways and destruction of alveolar walls, leading to poor ventilation.
Physiologic dead space= anatomical dead space plus alveolar dead space
Anatomical dead space= from nose/mouth to terminal bronchiole
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what does the normal columnar epithelium of airway change to in COPD?
Squamous epithelium
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what is anatomical dead space?
Anatomical dead space= from nose/mouth to terminal bronchiole cause they have no alveoli to participate in gas exchange
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what is it called when blood is perfused through an area of the lung without being ventilated, and thus, it returns to the left heart without being oxygenated?
right to left shunt
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what causes right to left shunt?
This can happen due to various pathological conditions where alveoli are filled with fluid or collapsed, preventing air from entering, even though blood flow persists.
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what is the V/Q for a shunt and why?
The V/Q ratio for a shunt is zero (V/Q = 0) because there is perfusion (Q) but no ventilation (V).
the gas pressures in the alveolus will reflect those of mixed venous blood. This can result from conditions like atelectasis or airway obstruction where air cannot enter certain parts of the lung.
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how do you differentiate physiological shunt from anatomical shunt?
Physiological shunts can occur due to pathological conditions in the lung where blood bypasses the alveoli. Anatomical shunts are normal shunts present in the body, like the blood that comes from the bronchial circulation and enters the left heart without passing through alveolar gas exchange.
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what type of shunt contribute to the normal difference between alveolar and arterial oxygen levels, known as the A-a gradient?
anatomical shunts
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what is the A-a gradient in a healthy person?
In healthy individuals, this gradient is small, typically between 6 to 9 mmHg, reflecting the small amount of blood that normally bypasses the alveoli and does not participate in gas exchange.
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what does V/Q of Infinity (V/Q = ∞) mean and what condition can it be seen in?
This occurs in an alveolus that is ventilated but not perfused. In other words, air is reaching the alveolus, but there is no blood flow in the capillaries around it to participate in gas exchange. The alveolar gas tension will equilibrate (meaning alveolar gas concentration of O2 and CO2 eventually becomes equal to that of environmental/breathed in air) with the inspired air since there is no removal or addition of gases from the blood. This is typically seen in conditions like pulmonary embolism where the blood flow to a portion of the lung is blocked [creating dead space].
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what type of ratio is it if the amount of air reaching the alveoli is equal to the blood flow in the pulmonary capillaries?
normal V/Q ratio =1
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what is the alveoli partial pressure of O2 and CO2 at normal V/Q ratio?
At this ratio, the partial pressure of oxygen (PAO2) in the alveoli is approximately 100 mmHg, and the partial pressure of carbon dioxide (PACO2) is approximately 40 mmHg when breathing air with a fractional concentration of oxygen (FIO2) of 0.21 (the concentration of oxygen in room air).
Partial pressure of O2 in air is 160 mmHg. concentration of CO2 in air is 0.04%
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what is Forced Expiratory Volume 1?
the amount of air a person can forcefully exhale in one second.
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What does Peak Expiratory Flow (PEF) indicate about a patient's respiratory function?
Peak Expiratory Flow (PEF) indicates the maximum speed of exhalation and can help diagnose and monitor diseases like asthma.
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how do you calculate vital capacity?
Vital Capacity (VC): The maximum amount of air that can be exhaled after a maximum inhalation. VC can be calculated by adding the ERV, VT, and IRV.
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how do you calculate inspiratory capacity?
Inspiratory Capacity (IC): The maximum volume of air that can be inhaled after a normal expiration. IC is the sum of VT and IRV.
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how do you calculate functional residual capacity?
Functional Residual Capacity (FRC): The volume of air present in the lungs at the end of passive expiration. FRC includes ERV and RV.
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how do you calculate total lung capacity?
Total Lung Capacity (TLC): The total volume of air the lungs can hold. TLC is the sum of the VC and RV.
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what is asthma?
Asthma is a common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm.
Episodic and Reversible Bronchoconstriction: Asthma involves episodes of bronchoconstriction, where the airways narrow due to the contraction of the surrounding smooth muscle. This constriction is typically reversible, either spontaneously or with medication.
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which part of the bronchial tree is most susceptible to constriction from asthma?
The bronchioles, the smaller airway passages that branch off from the larger bronchi, are particularly susceptible to constriction in asthma. This is due to their smaller diameter and the fact that they have a higher ratio of smooth muscle to cartilage compared to larger airways.
161
which 2 inflammatory cells increase in number in the airways due to asthma?
Chronic inflammation in asthma leads to changes in the airways, including swelling and an increase in the number of inflammatory cells, such as eosinophils and mast cells. This inflammation contributes to airway hyperresponsiveness, mucus production, and the symptoms of asthma.
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what causes airway swelling, hyperresponsiveness, hypertrophy, hyperactivity (airway narrows easier and mor often), and mucus production in asthma?
chronic inflammation
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what is the hallmark symptom of asthma?
Increased mucus production is a hallmark of asthma. The mucus can be thicker than normal and can plug the airways, contributing to the obstruction and making it difficult to breathe.
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what are the triggers for allergic/extrinsic asthma?
Allergic (Extrinsic) Asthma: Triggered by external allergens such as pollen, dust mites, mold, or pet dander. It is associated with an immune response that leads to inflammation and symptoms of asthma.
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what are triggers for nonallergic/intrinsic asthma?
may be caused by factors such as stress, exercise, cold air, or infections.
chemicals (aspirin, NSAIDs, ozone free radicals).
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what is is a severe form of asthma where the airway obstruction is not relieved by usual treatments such as inhaled bronchodilators. It can lead to respiratory failure and is considered a medical emergency?
status asthmaticus
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which type of asthma is considered medical emergency?
status asthmaticus
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what type of hypersensitivity is extrinsic asthma and why?
Type 1 Hypersensitivity: Extrinsic asthma is often a result of a Type 1 hypersensitivity reaction, which is an allergic response. This reaction occurs when the immune system overreacts to inhaled allergens such as pollen, dust mites, mold, animal dander, or certain foods.
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does asthma have a genetic component?
yes
Genetic Predisposition: It is commonly seen in children who have a genetic predisposition to develop allergies. This means that they have inherited genes from their parents that increase their likelihood of becoming allergic.
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what's a common symptom of asthma?
wheezing
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what are some other symptoms of asthma besides wheezing?
Wheezing: This is a common symptom of asthma and refers to the high-pitched whistling sound that occurs due to narrowed airways during breathing, particularly during exhalation.
Cough: The cough in asthma is often chronic and can be worse at night or early in the morning. It may be dry or productive of clear mucus.
Mucus Production: Increased mucus production is a response to the inflammation in the airways and can contribute to the obstruction and symptoms.
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what is an indication that intubation is needed in a child with asthma?
In children with asthma, a significant concern is respiratory fatigue, which can lead to CO2 retention and decreased responsiveness and [cause sleepiness]. Such symptoms are serious and may warrant emergency intervention, including intubation to secure the airway and support breathing.
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what are some finding for asthma during physical exam?
Tachycardia: An increased heart rate often occurs in response to low oxygen levels or as a side effect of medications used in asthma.
Tachypnea: Increased respiratory rate is a common finding and is reflective of the body's attempt to maintain adequate oxygen levels despite narrowed airways.
Use of Accessory Muscles: In an effort to breathe more effectively, individuals with asthma may use the muscles in the neck and chest, other than the diaphragm, to help with breathing.
Pulsus Paradoxus: This is a sign where there is a greater than normal drop in systolic blood pressure during inspiration. It can occur in severe asthma exacerbations due to the negative intrathoracic pressure generated during attempts to breathe against obstructed airways. (fall of systolic pressure > 10 mmHg during inspiration)
Prolonged Expiratory Phase: The expiration phase of breathing is notably longer in asthma patients because of the narrowed airways and resistance to airflow.
173
how soon after exposure to allergens or irritants is early response of asthma vs late response?
early response 0-2 hrs
late response 4-12 hrs
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which 2 chemicals are released by mast cells to cause acute bronchoconstriction during early phase of asthma?
leukotriene and histamine
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what chemical is activated by mast cells and T-cells in late response phase of asthma?
eosinophils
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what does the inflammation in late response asthma cause?
bronchoconstriction but can also cause symptoms such as rhinitis (inflammation of the nasal mucous membrane) and conjunctivitis (inflammation of the eye's conjunctiva).
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