Cardiopulm Unit 9 Restrictive Lung Disease Flashcards
What is Restrictive Lung Disease?
A group of disorders characterized by a reduction in lung expansion, leading to decreased lung volumes and impaired pulmonary ventilation. This reduction is due to various factors such as stiffness of the lung tissue, limitations in chest wall movement, or neuromuscular dysfunction, all of which increase the effort required for breathing.
Restrictive Lung Disease has 2 causes, what is considered Cause 1?
Caused by Intrinsic Pulmonary Disorders
Chronic, Progressive Driven by Fibrotic Changes
- Interstitial Pulmonary Fibrosis (IPF)
- Inhaled particles (e.g., asbestos, silicones)
- Radiation pneumonitis
- Sarcoidosis
Acute and Potentially reversible, Driven by Fluid Accumulation and Inflammation
- Pulmonary congestion/edema
- Acute Respiratory Distress Syndrome (ARDS)
- Pneumonia (PNA)
Restrictive Lung Disease has 2 causes, what is considered Cause 2?
Neuromuscular, Pleural, chest wall dysfunctions
- Lungs are intrinsically normal but respiratory efforts are unable to expand the lung parenchyma, leading secondarily to alveolar collapse, inflammation, and eventually fibrosis.
- Muscular dystrophy, Pneumothorax, SCI, phrenic nerve paralysis, myasthenia gravis, ALS, GBS, scoliosis, morbid obesity, ankylosing spondylitis, burns, surgery, etc
What are the Hallmark SIGNS of Restriactive Lung Disease?
- Decreased lung volumes
- Decreased breath sounds
- Tachypnea
- Increased work of breathing
- V/Q mismatching (with hypoxemia when severe)
What are the Hallmark SYMPTOMS of Restriactive Lung Disease?
- Dyspnea
With Restrictive Lung Disease, associated SIGNS depend on when etilogy such as?
- Dry inspiratory crackles
- Decreased diffusing capacity
- Cor Pulmonale
With Restrictive Lung Disease, associated SYMPTOMS depend on when etilogy such as?
- Cough (often dry)
- Wasted, emaciated appearance
-Normally, ~ 5% of O2 is used to support work of breathing; in RLD, this can increase to ~ 25%.
-This larger fraction of total body metabolic energy diverted to respiratory muscles leaves a smaller fraction available for working limb muscles during exercise
WIth Restrictive Lung Disease, with age, what happens when there are Changes in the Chest Wall?
- There is decrease strength of respiratory muscles, this increases O2 consumption in respiratory muscles and a decrease in MVV (Max. voluntary ventilation).
- There is a decrease in chest wall compliance, this also increases O2 consumption in respiratory
- The incresae in O2 consumption in respiratory muscles lead to increase minute ventilation, an increase in work of breathing, and may increase respiratory muscle fatigue
This all leads to a Decrease in Pulmonary Efficiency, this signifies a decline in the respiratory system’s capability to meet the bodies demands, especially during stress or illness
WIth Restrictive Lung Disease, with age, what happens when there are Changes in the Lungs?
- As Alveolar compliance decreases, the elastcity of the alveoli diminishes, this results in an increase RV
-There is trapped air that contirbutes to higher physiological dead space (where gas exchange does not happen). With this air trapping, VC also decreases. s trapped in the lungs. This reduction in vital capacity signifies decreased lung efficiency and capacity for ventilation. Poor V/Q matching occurs as areas of the lung become under-ventilated relative to their blood supply, leading to hypoxemia. - There’s also a noted decrease in the diffusing capacity of the lung for carbon monoxide (DLco), which implies that the transfer of gases from the alveoli to the blood is less efficient, often due to a loss of alveolar surface area. With these changes comes a decrease in the optimal V/Q matching. Consequently, there’s a mild but significant reduction PaO2
What is Atelectasis?
A condition where all or part of a lung becomes airless and collapses, which can lead to decreased gas exchange and potentially hypoxia
- Atelectasis not typically classified as a “restrictive lung disease” but is associated with several conditions
What is Obstructive Atelectasis?
A consequence of blockage of an airway. Air retained distal to the occlusion is resorbed from nonventilated alveoli, causing the affected regions to become totally gasless and then collapse
With Non-obstructive Atelectasis, what is Relaxation (i.e., Passive/Collapse) Atelectasis?
This ensues when contact between the parietal and visceral pleurae is disrupted (e.g., as within pleural effusion, pneumothorax, or diaphragmatic dysfunction).
- This can also happen in the setting of small TVs due to pain, bed rest, sedatives, etc
With Non-Obstructive Atelectasis, What is Adhesive Atelectasis?
When there is a surfactant deficiency and there is a greater tendency of the alveoli to collapse. Conditions include acute respiratory distress syndrome (ARDS), pulmonary embolus, and pneumonia
With Non-obstructive Atelectasis, what is Compressive Atelectasis?
This occurs when a space occupying lesion of the thorax (e.g., pleural effusion or solid mass of the chest wall, pleura, or parenchyma) presses on the lung and causes the lung volume to diminish to less than the usual resting volume (i.e., the functional residual capacity)
What are the Risk Factors for Atelectasis?
- Anesthesia
- Pain
- Abnormal breathing patterns due to central breathing centers disruption
- Restricted chest movement, due to bone or muscle problems, or recent thoracic or abdominal surgery
- Injuries
- Prolonged bed rest/Inactivity
- Mechanical ventilation
- Lung diseases, such as asthma, lung cancer, PNA
- Lung compression
- Increased lung secretions
- Weakened respiratory muscles (e.g. diaphragm)
- Medications such as narcotic, sedatives, relaxants
- Heart failure
- Obesity
- Conditions that limit physical activity, such as a stroke, spinal cord injury, heart problems, trauma, or severe illness
- Premature birth if lungs are not fully developed
- Ineffective or absent surfactant
What are the S/S of Atelectasis?
Atelectasis may or may not cause symptoms. Small areas of collapse are less likely than larger areas to cause symptoms. Major atelectasis decreases the amount of oxygen available throughout the body and cause RLD signs/symptoms. In general, the symptoms the patient experiences with atelectasis are more likely from the cause of the atelectasis (e.g., post-op pain)
With those patients that have Atelectasis and are Post-op or Bed Ridden, what does treatment/management include?
Post-op or bed ridden patients can respond to interventions like deep breathing, incentive spirometry, and coughing. Prevention should be goal for all hospitalization patients.
During the Physical Exam, what breath sounds may we hear with those patients with Atelectasis (Obstructive Type)?
Diminished over absent
During the Physical Exam, what Adventitous sounds may we hear with those patients with Atelectasis (Obstructive Type)?
If obstruction is partial, wheezing or crackles may be heard due to air passing through or around the obstruction
During the Physical Exam, what Transmitted Voice sounds may we hear with those patients with Atelectasis (Obstructive Type)?
None
During the Physical Exam, what Percussion Note may we hear with those with Atelectasis (Obstructive Type)?
Dull
During the Physical Exam, where may we find the trachea when observing those patients with Atelectasis (Obstructive Type)?
Possibly shifted toward the affected side if severe
During the Physical Exam, what breath sounds may we hear with those patients with Atelectasis (Compressive Type)?
Diminished over absent
During the Physical Exam, what Adventitous sounds may we hear with those patients with Atelectasis (Compressive Type)?
Typically absent, as the lung tissue is compressed and is not moving through the area
During the Physical Exam, what Transmitted Voice sounds may we hear with those patients with Atelectasis (Compressive Type)?
None
During the Physical Exam, what Percussion Note may we hear with those with Atelectasis (Compressive Type)?
Dull
During the Physical Exam, where may we find the trachea when observing those patients with Atelectasis (Compressive Type)?
Possibly shifted away the affected side if severe
What affects of Obesity have on breathing?
- Obesity requires additional oxygen
- Produces additional CO2
- Decreases the compliance of the thorax and therefore increases the work of breathing
- (In the abdominal) exerts pressure on the abdominal contents and diaphragm
-Results in decreased lung expansion and early closure of the small airways and alveoli, especially at the bases or the dependent regions of the lung. These areas are hypoventilated relative to their perfusion, which can markedly increase the ventilation–perfusion mismatching and result in hypoxemia
With overweight individuals, what does Obesity-Hypoventilation Syndrome result from?
Results when there is an imbalance between the ventilatory drive and the ventilatory load
With patients with Kyphoscoliosis, if the patient has < 70° of spinal curvature, how would this affect respiration?
< 70 degrees do not tend to produce pulmonary Sx
With patients with Kyphoscoliosis, if the patient has 70-120° of spinal curvature, how would this affect respiration?
May cause some respiratory dysfunction, and respiratory sx may increase with age as the angle increases and as the changes associated with aging affect the lung
With patients with Kyphoscoliosis, if the patient has >120° of spinal curvature, how would this affect respiration?
> 120 degrees are commonly associated with severe RLD and respiratory failure
With Kyphoscoliosis, what is the pathophysiology of pulmonary sx?
- Decreased chest wall compliance
- Ventilation–perfusion matching is markedly impaired
-Alveolar hypoventilation - Pulmonary hypertension may lead to cor pulmonale
- The typical increase in the work of breathing is further worsened by impaired the mechanical disadvantages from the thoracoabdominal deformity.
When the VC is decreased to less than 40% of the predicted value, cardiorespiratory failure is likely to occur. This usually occurs in the fourth or fifth decade of life. Sixty percent of deaths are caused by respiratory failure or cor pulmonale.
With Crush Injuries, how can Rib Fractures impact breathing?
- Breathing will be shallow due to pain and muscular splinting
- Underlying hemothroax (if present) can lead to acute and chronic restriction
With Crush Injuries, what is Flail Chest? What are some long-term disabilites that may come from this?
- Injury to the free-floating segment ribs
- Long-term pulmonary disability following flail chest wall deformity, dyspnea on exertion, and mild restrictive pulmonary dysfunction for months to years
With Crush Injuries, what is Lung Contusion?
– Bruising of the lung tissue, which can lead to inflammation, edema, and hemorrhage within the lung parenchyma. The injured lung tissue may become stiff and less compliant, making it more difficult for the lungs to expand, leading to a restrictive pattern on pulmonary function tests.
– ~50-70% develop pneumonia
What is the Main Goal for Crush Injuries?
(Rib Fx, Flail Chest, Lung Contusion)
Pain management and reestablish normal breathing or at least a level of ventilation that can support necessary activities (e.g. ADLs) using deep breathing, positioning, and supported coughing
What is Pneumonia? What does this lead to?
An inflammatory process of some part of the lung where gas exchange occurs that usually begins with an infection in the lower respiratory tract
- Leads to decreased functional lung volume as consolidated air spaces do not inflate as easily (reflecting decreased compliance)
What are the 4 categories of Pneumonia (PNA)?
- Community-acquired PNA
-Streptococcus PNA or pneumococcus is the most common type - Hospital-acquired PNA (HAP)
-Represents the second most common type of nosocomial infection in USA (exceeded by UTI) - Health-care-associated PNA (HCAP)
- Ventilatory-associated PNA (VAP)
What are the Presentations of Bacterial Pneumonia (PNA)?
Abrupt onset, Lobar consolidation, high fever, chills, moderate-to-severe respiratory distress, focal auscultatory findings,productive cough, pleuritic pain, and elevated WBC
What are the Presentations of Viral Pneumonia (PNA)?
Gradual onset, preceding upper airway symptoms, diffuse/bilateral auscultatory findings, low-to-moderate fever,
and normal WBC, nonproductive cough
During the Physical Exam, what breath sounds may we hear with those patients with Lobar Pneumonia?
Bronchial
During the Physical Exam, what Adventitous sounds may we hear with those patients with Lobar Pneumonia?
Crackles, maybe a pleural friction rub if pneumonia has extended to pleural surface
During the Physical Exam, what Transmitted Voice sounds may we hear with those patients with Lobar Pneumonia?
(+) Test for transmitted voice sounds
During the Physical Exam, what Percussion Note may we hear with those with Lobar Pneumonia?
Dull
During the Physical Exam, where may we find the trachea when observing those patients with Lobar Pneumonia?
Midline
Applying the Hierarchy to a case of Pneumonia, what are the Acute Effects of Mobilization and Exercise?
- Mobilization can help redistribute blood flow to better Ventilated areas of the lungs, improving the match between ventilation and perfusion and thereby enhancing oxygenation.
- Movement and increased respiratory rate help in mobilizing secretions, facilitating their clearance from the respiratory tract.
- Exercise can increase the need for deeper breaths and subsequently stimulate the cough reflex to clear mucus
Applying the Hierarchy to a case of Pneumonia, How can Body Positions be beneficial?
- Consider the role of positioning to optimize V/Q matching, such as sitting up or lying on the side that is less affected to maximize air entry into the healthier lung segments.
- Educate the patient on the importance of frequent changes in position to prevent atelectasis and to promote lung expansion and secretion clearance.
Applying the Hierarchy to a case of Pneumonia, How can Breathing Control Maneuvers be beneficial?
- Consider techniques to enhance alveolar ventilation (diaphragmatic breathing, lateral costal breathing, etc.)
- Paced breathing might be used during activities to reduce dyspnea and improve efficiency.
Applying the Hierarchy to a case of Pneumonia, How can Coughing Manuvers be helpful for those patients?
Effective coughing techniques can be taught to help clear secretions, as pneumonia often leads to increased mucus production
Applying the Hierarchy to a case of Pneumonia, How can Postural Drainage Positioning be beneficial?
Positioning the patient to facilitate gravity-assisted drainage of secretions from different lobes of the lungs can help to clear mucus that may be obstructing airways, especially in bacterial pneumonia where there is often a significant productive cough
This is used when Mobilization, Body position, Breathing/Coughing manuvers dont work
Applying the Hierarchy to a case of Pneumonia, How can Manual Techniques be beneficial?
Manual chest physiotherapy, including percussion and vibration, can be utilized to loosen pulmonary secretions, making them easier to expectorate
This is used when Mobilization, Body position, Breathing/Coughing manuvers dont work
With Surgical Therapy, what are 3 Primary Factors of Pulmonary Dysfunction?
- The anesthetic agent
-decrease in the pulmonary arterial vasoconstrictive response to hypoxia - The surgical incision or procedure itself
-Lobectomy, Pneumonectomy, Thoracoplasties
-Upper abdominal surgery, the VC is transiently decreased by 55% and the FRC by 30% - The pain caused by the incision or procedure
-tone in the muscles (muscular splinting) of the thorax and the abdominal wall increases decreases chest
wall compliance
With Pulmonary Surgical Therapy, when do the lungs volume decreases reach their greatest values?
- When do these values return to relative normal and when is full recovery?
These decreases reach their greatest values 24-48hrs after surgery
- Lung Volumes then return to relatively normal values in 5 days
- Full recovery may take 2 weeks
What is ARISCAT Score?
Predicts risk of pulmonary complications after surgery, including respiratory failure.
What does it mean when a patient has an ARISCAT score of < 26?
This is a Low Risk of developing pulmonary complications
What does it mean when a patient has an ARISCAT score of 26-44?
They are at Medium/Intermediate Risk of developing pulmonary complications
What does it mean when a patient has an ARISCAT score of ≥ 45?
These patients are at High Risk of Pulmonary Complications
- Patients identified as high risk may be targeted for intensive prophylactic respiratory intervention, thus ensuring appropriate allocation of physiotherapy resources and limiting the likelihood of clinically significant pulmonary complications
Algorithm
What should be done when a patient is s/p thoracic or abdminal surgery?
We assess Static Functioning of Respiratory System: SpO2, RR, Dyspnea and Work of Breathing
Algorithm
A patient is s/p thoracic or abdminal surgery, We assess Static Functioning of Respiratory System: SpO2, RR, Dyspnea and Work of Breathing. What would happen if the patient is Favorable?
- Mobilize the patient out of bed
- Teach patient deep breathing exercises and huff/cough with wound support as needed
Algorithm
A patient is s/p thoracic or abdminal surgery, We assess Static Functioning of Respiratory System: SpO2, RR, Dyspnea and Work of Breathing. What would happen if the patient is Unfavorable (but clinically stable)?
- Position the patient in a stable, supported upright posture
- Teach patient deep breathing exercises andn huff/cough with wound support as needed
- We then Reassess Static Functioning of Respiratory System: SpO2 RR, Dyspnea, and Work of Breathing
Algorithm
A patient is s/p thoracic or abdminal surgery, We assess Static Functioning of Respiratory System: SpO2, RR, Dyspnea and Work of Breathing. The patient was found unfavorable (but clinically stable). What happens when we reassessed the Static Respiratory system and they are found to be favorable?
We progress toward the LIPPSMAck POP ambulation protocol
Algorithm
A patient is s/p thoracic or abdminal surgery, We assess Static Functioning of Respiratory System: SpO2, RR, Dyspnea and Work of Breathing. The patient was found unfavorable (but clinically stable). What happens when we reassessed the Static Respiratory system and they are still found to be Unfavorable?
Consider Positive Expiratory Pressure Device and/or Nebulization. If this fails, consider postural drainage +- P&V and/or consult with RT or nursing for suctioning
- If ineffective, contact physician
What is Pneumothorax?
When air is in the pleural space communicates freely with the outside environment
- Effective negative pleural space pressure cannot be maintained, the patient’s ability to move air into the lungs is severely diminished.
What is Tension Pneumothorax?
This means air can enter the pleural space BUT cannot escape into the external environment. This is an acute life-threatening situation
- As air continues to enter and becomes trapped in the pleural space, the intrapleural pressure rapidly increases. This causes the lung on the involved side to collapse. The mediastinal structures are pushed away from the affected side
What can a Tracheal Shift be caused by?
Disproportionate intrathoracic pressures or lung volumes between the 2 sides of the thorax
What does it mean when the contents of the thorax shifts Toward the affected side?
This happens when the lung volume or intrathoracic pressure on that side is decreased. This can happen after a lobectomy or pneumonectomy or a large degree of atelectasis
- When the shift goes to the affected side in the patient after a lobectomy or pneumonectomy, the patient should be cautioned against lying on the affected side because this would only increase the mediastinal shift
What does it mean when the contents of the thorax shifts to the unaffected side?
When there is increased pressure on the same side, as happens in a pleural effusion, a tumor, or an untreated pneuomothorax
How do we palpate for a Tracheal Shift?
Palpation proceeds with the tip of the index finger being placed in the suprasternal notch, first medially to the left sternoclavicular joint and pushed inward toward the cervical spine. Then the index finger is placed medial to the right sternoclavicular joint and pushed inward toward the cervical spine
What does it mean when there is a Significant shift to the unaffected side? What happens if the shift is caused by Pneumothorax or a Pleural Effusion?
Aggressive Treatment is usually indicated
- If the shift is caused by a pneumothorax, a chest tube is usually inserted immediately. In the case of the large pleural effusion, a thoracentesis may be performed to drain the fluid or to evaluate the contents of the fluid or both
What does it mean when there is a tracheal shift to the Affected side after a lobectomy or pneumoectomy?
The patient should be cautioned against
lying on the affected side because this would only increase the mediastinal shift
During the Physical Exam, what breath sounds may we hear with those patients with Pneumothorax?
Decreased or absent
During the Physical Exam, what Adventitous sounds may we hear with those patients with Pneumothorax?
None, maybe a pleural rub
During the Physical Exam, what Transmitted Voice sounds may we hear with those patients with Pneumothorax?
None
During the Physical Exam, what Percussion Note may we hear with those with Pneumothorax?
Hyperresonant
During the Physical Exam, where may we find the trachea when observing those patients with Pneumothorax?
Possibly shifted away from affected side if severe
What is Pleural Effusion?
Although not a primary lung parenchyma disease
- This can lead to RLD pattern due to the physical limitation on lung expansion caused by the presence of fluid
With Pleural Effusion, what is Physical Restriction?
The fluid in the pleural space exerts pressure on the lungs, preventing them from fully expanding during inhalation and reducing the volume available for the lung to expand, leading to a reduction in lung volume such as vital capacity (VC) and Total lung capacity (TLC)
With Pleural Effusion, what may cause Impaired Gas Exchange?
The compression of the lung tissue can also adversely affect the efficiency of gas exchange by collapsing alveoli, further contributing to the Sx of dyspnea
During the Physical Exam, what breath sounds may we hear with those patients with Pleural Effusion?
Decreased or absent
During the Physical Exam, what Adventitous sounds may we hear with those patients with Pleural Effusion?
None, maybe a pleural rub
During the Physical Exam, what Transmitted Voice sounds may we hear with those patients with Pleural Effusion?
None
During the Physical Exam, what Percussion Note may we hear with those with Pleural Effusion?
Dull
During the Physical Exam, where may we find the trachea when observing those patients with Pleural Effusion?
Possibly shifted away from affected side if severe
What are the 2 main categories of Pulmonary Edema?
- Cardiogenic Pulmonary Edema
- NonCardiogenic Pulmonary Edema
What is Cardiogenic Pulmonary Edema?
An increase in the pulmonary capillary hydrostatic pressure, often secondary to left ventricular failure
What causes Noncardiogenic Pulmonary Edema?
Has a multitude of causes, including:
- increased capillary permeability
- lymphatic insufficiency
What is the effect of Pulmonary Edema?
What breath sounds would we hear?
With fluid in the alveoli and the interstitium, lung compliance is decreased ➡️ ventilation–perfusion mismatching is increased ➡️ gas exchange is disrupted ➡️ the work of breathing is increased ➡️ and there is RLD and in severe cases acute respiratory failure.
- Breath sounds usually reveal crackles.
What is a Pulmonary Emboli?
- This is a complication of venous thrombosis in which blood clots or thrombi travel from a system vein through the right side of the heart and into the pulmonary circulation where they lodge in branches of the pulmonary artery
With Pulmonary Embolism, many events go unnoticed because they are clinically silent. What are the classic Triad Sx they may experience?
Dyspnea, Hemoptysis, and Pleuritic Chest Pain
Hemoptysis, meaning coughing up blood or blood-tinged sputum from the respiratory tract
What is Interstitial Lung Disease? What does this cause?
A group of lung diseases affecting the interstitium (the tissue and space around the air sacs of the lungs)
- This causes interstitial fibrosis and impairment of lung function
With Interstitial Lung Disease, what are the 4 Buckets this disease can be grouped to?
- Connective tissue related
- Sarcoidosis
- Hypersensitivity
- idiopathic
What happens to the lungs with Idiopathic Pulmonary Fibrosis (IPF)?
- There is thickening and scarring of the interstitial tissue, the space between alveoli. This Fibrosis stiffens the lung tissue; making it less compliant
- Normal lung architecture is disrupted by fibrosis. The bronchioles and alveoli are replaced with irregular, scarred tissue. This disrupts airflow and reduces the lung’s ability to expand
- The fibrotic tissue does not allow for the efficient transfer of O2 into the blood or the removal of CO2 from it
- In advanced IPF, the formation of honeycomb-like cystic spaces can be seen. This represents areas of destroyed and over inflated alveoli, surrounded by fibrous tissue
Overall, these structural changes in the lung result in a decreased total lung capacity (TLC) and vital capacity (VC). The lung’s inability to expand fully leads to a reduction in the volume of air that can be inhaled during each breath, which translates clinically to symptoms such as shortness of breath and chronic dry cough. Over time, these changes lead to progressive worsening of respiratory function, and patients with IPF often experience a gradual decline in their exercise tolerance and quality of life
Individuals with Idiopathic Pulmonary Fibrosis (IPF) may experience what? What is the significance of this?
May experience acute respiratory deteriorations, with development of new or worsening dyspnea and increased oxygen requirements
- Typically referred to as “Acute Exacerbations”, with a median survival of only 3-4 months post-event
What are the Goals for Idiopathic Pulmonary Fibrosis (IPF)?
The goals of treatment in IPF are essentially to reduce the symptoms, slow disease progression, prevent acute exacerbations, and prolong survival
- Meticulous attention to breathing techniques and verbal reinforcement during activity may help reduce subject anxiety and enhance the quality of the measurements
What is Sarcoidosis? What is the effect of this over time?
When idiopathic granulimatous inflammatory disorder affects many systems (multi-system disease) in the body, especially the lung.
These granulomas can be found in the lungs, lymphs, eyes and skin
- Over time, these granulomas can lead to fibrosis, which is the formation of scar tissue. Fibrosis is less elastic than healthy lung tissue, leading to a decrease in lung compliance
How does Sarcoidosis affect the lungs?
Reduces lung compliance, impairs gas exchange, and contributes to restrictive lung disease, often leading to hypoxemia and dyspnea
With Sarcoidosis, what are 3 distinctive features in the lungs?
- Alveolitis (earlies feature found)
- Formation of round or oval granulomas
- Pulmonary Fibrosis
How does Acute Respiratory Distress Syndrome (ARDS) occur?
When the lungs become less elastic, this occurs as a result of a disease that causes inflammation, leading to increased pulmonary vascular permeability, increased lung weight and loss of aerated tissue
How does Acute Respiratory Distress Syndrome (ARDS) affect the lungs?
- The lungs become less elastic due to inflammation, edema and the eventual development of fibrotic tissue, making them more difficult to expand during inhalation
- A ⬇️ in VC, functional residual capacity (FRC) and TLC) follows,.
- Furthermore a build up of fluid, inflammatory cells and fibrotic tissue within the alveolar space impairs gas exchange, leading ultimately to hypoxemia and hypercapnia and respiratory failure
With Acute Respiratory Distress Syndrome (ARDS), what is Alveolar Injury?
Type 1 pneumocyte, which are essential for the gas exchange process, are injured, disrupting the alveolar-capillary barrier, allowing fluid from the capillaries to leak into the alveolar space
With Acute Respiratory Distress Syndrome (ARDS), what is Endothelial Cell Injury?
Injuries to the endothelial cells of the blood vessels leads to increased permeability
With Acute Respiratory Distress Syndrome (ARDS), what is Edema and Hyaline Membrane Formation?
Alveolar and endothelial cell injury lead to the accumulation of edema in the alveolar space. This fluid is rich in proteins, which together with dead cells and fibrin, lead to the formation of hyaline membranes on the alveolar surface. These membranes further impair gas exchange
