Obstructive and Restrictive Lung Disease Flashcards
what is Respirtory Lung Dysfunction: aka Restrictive Lung exspanison diminshed
RLD: an abnormal reduction in pulmonary ventilation. Lung expansion is diminished. The volume of gas moving in and out of the lungs is decreased.
What things physilogically affect the Respiratory Lung Dysfunction
Aspects of ventilation contributing to RLD
Compliance of the lung and the chest wall
Alteration in lung volumes and capacities
Work of breathing
What is Compliance and what happens if it is reduced???
Physiological link that establishes a relationship between the pressure exerted by the chest wall and/or the lungs and the volume of air that can be contained within the lungs
In RLD, chest wall and/or lung compliance is reduced.
ranspulmonary gradient needed just to expand the lungs.
Decreased chest wall compliance limits thoracic expansion and therefore, lung inflation, even if lung compliance is normal.
What is diminshed when Respiratory lung dysfunction occurs???
ERV goes up or down
Tidal volume - goes up or down
IRV- up or down
RLD eventually causes all lung volumes and capacities to be reduced.
When the lung becomes less compliant, the IRV is diminished
Tidal volume also decreases as the work of breathing increases
ERV is reduced, this reduction is particularly pronounced if lung compliance is the principle etiology of the RLD.
What the most two common measures used to ID RLD while using spirometer? and What is indicated by a decrease in TLC and FRC ?
Total lung capacity: the volume in the lungs at maximal inflation, the sum of VC and RV.
Vital capacity: the volume of air breathed in after the deepest inhalation
http://en.wikipedia.org/wiki/Lung_volumes
Total Lung Capacity and Vital Capacity are the two most common measures used to identify RLD
Decreases in TLC and FRC are a direct result of a decrease in lung compliance
What is the 3 ways that work of breathing increases
In RLD, work of breathing is increased.
Work of breathing is increased by:
Increased airway resistance
Increases in flow rates
Decreases in lung or chest wall compliance
Compensatory mechanism
How does the lungs deal with a decreased breathing compliance.
To overcome the decrease in pulmonary compliance, the respiratory rate is usually increased
Accessory muscles of inspiration are recruited either at rest or at a lower activity level, in order to assist with chest wall expansion.
How much does a normal person use of VO2 at rest vs. Someone with RLD how much VO2 do they use???
In normal persons at rest, the body uses less than 5% of the VO2 (ie 3-14 ml O2/min) to support the work of breathing
With RLD the % of VO2 required to support the work of breathing can be 25% or more
What are the six classic signs of Respiratory Lung Dysfunction
Six classic signs often indicate and are consistent with RLD
Tachypnea
Hypoxemia
Alteration in breath sounds on auscultation
Decrease in lung volumes/capacities
Decreased diffusing capacity
Cor Pulmonale
What is tachypnea???
Tidal Volume- by the way is the NORMAL lung volume without any extra effort being made amount of air inhaled and exhaled.
An involuntary adjustment is made to increase the respiratory rate to compensate for the decrease in tidal volume thereby maintaining the same minute ventilation
Early in RLD, overcompensation may occur which results in alveolar hyperventilation
What is hypoxemia? How does it come about
Ventilation-Perfusion Mismatching
May occur as a result of:
Changes in the collagenous framework of the lung
Scarring of capillary channels
Distortion or narrowing of the small airways
Compression from tumors in the lung
Bony abnormalities of the chest wall
Decreased oxygen in the blood.
What happens with Tidal voulme, IRV, ERV,
Decrease in Tidal volume
Decrease in inspiratory reserve volume
Decrease in expiratory reserve volume
Residual volume is decreased, but degree of decrease may not be as dramatic as that seen in the IRV and ERV
Why does the diffusion capacity decrease with RLD? think scarring
DLCO is decreased as a result of a widening of the interstitial spaces due to scar tissue, fibrosis of the capillaries, and ventilation-perfusion abnormalities.
In RLD DLCO has been measured at less than 50% of predicted.
What is Cor Pulmonale?
Right sided heart failure resulting from hypoxemia, fibrosis, and compression of the pulmonary capillariespulmonary hypertension.
Because the pulmonary capillaries are fibrotic, they are less capable of distending to handle the ordinary increase in cardiac output expected with exercise
Symptoms associated with RLD
Dyspnea
Dry non productive cough
Wasted, emaciated appearance
What is the treatment typically for RLD
If etiological factors are permanent or progressive, supportive measures are mostly utilized:
Antibiotic therapy
Measures to promote adequate ventilation
Supplemental oxygen
Prevention of accumulation of pulmonary secretions
Nutritional support
What is obstructive lung dysfunction
Diseases of the respiratory tract that produce an obstruction to airflow. This obstruction to airflow can ultimately affect both the mechanical and gas exchanging capability of the lungs.
Typical changes seen with Obstructive lung disease
Increased mucus production/impaired mucus secretion
Inflammation of the mucosal lining of the bronchi and bronchioles
Mucosal thickening
Spasm of the bronchial smooth muscle
Two ways that the bronchioles shutdown.
Narrowing of the bronchial lumen
Increased resistance to airflow
Loss of normal elastic recoil of lung tissuetendency for the airways to collapse
hyperinflation
What does the work rate of breathing increase
Respiratory muscles must work harder to overcome the increased airway resistance
Diaphragm excursion may be limited due to hyperinflation of the lungs
Alveolar ventilation is reduced
Alveolar-capillary membrane surface area may be reduced.
To determine the diaphargmatic distance you can tap on the chest to hear the hollowness upon tapping on it. Also in an X-ray if the lungs are flat then then they are pushing down on the diapharggm and the diaphragm is not expanded
Clinical manisfestations or Signs of Obstructive Lung Disease or OLD
Signs Hypoxemia Increased production of mucus/impaired clearance Pulmonary Hypertension Polycythemia Cor Pulmonale
External signs of OLD
Chronic cough
Expectoration of mucus
Wheezing
Dyspnea on Exertion
Classfications of Obstruction
Bronchi or airways with cartilage in their walls (>2mm in diameter)
Bronchioles or airways without cartilage in their walls (<2mm in diameter)
Lung parenchyma (alveolar units): portion of the lung involved in gas exchange.
What are some enviormental factors that can lead to Obstructive Lung Disease and what decade of life does it usally come about???
Environmental factors Pollution Noxious gases Occupational exposures Cigarette smoking
Functionally, not notable until the sixth or seventh decade of life
When does compliance start to decrease in an individual and why does compliance start to decrease.
Compliance of the pulmonary system starts to decrease at about age 20
Thorax undergoes changes
Decalcification of ribs
Calcification of costal cartilage
Why does control of ventilation start to decrease what receptors start to lose their abilities
Control of ventilation undergoes significant change
Peripheral chemoreceptors are not as responsive to hypoxia
Central receptors are not as responsive to acute hypercapnea- the dam nigger meant to say hypercapnia which is a increase in CO2 in the body and the body losses its ability to detect after a certain amount of time.
what do EEG studies show about OLD.
Lung tissue itself shows enlargement of the air spaces owing to enlargement of the alveolar ducts and terminal bronchioles
Alveolar surface area decreases
EEG studies have shown that total nocturnal sleep time is shorter with more frequent awakenings.
What happens with old age
Does TLC change??
Does RV change??
VC?
MVV?
Flow rates??
PFTs (Things with old age) TLC (total lung capacity are usually unchanged RV is increased VC is decreased by about 25% by age 70 Flow rates are decreased MVV is decreased by about 30% Diffusing capacity is decreased
Do chest x-rays show bony changes within the thorax after old age?
ABG- Does PaO2 decrease by age 70? What about CO2 does it increase or decrease
CXR can show a variety of changes in the bony thorax and in the lung parenchyma
ABGs: the PaO2 is normally decreased to about 75mm Hg at age 70; PaCO2 is normal or slightly elevated
What about cardiovascular changes with old age
Does SV, CO, HRmax decrease or increase
Breath sounds: auscultation often reveals slightly diminished breath sounds
CV findings:
HRmax decreases
SV decreases
CO decreases
Why don’t adults realize the decreased lung capacity with old age??? (2 ) reasons
Pulmonary reserve is quite large, so that individuals do not usually note changes until the 7th decade.
Often individuals become more sedentary, especially those with comorbidities in other systems.
How much can a sedentary person improve his or her cardiovascular capabilites once starting a new exercise routine.
A sedentary elderly person beginning a regular exercise routine can improve their maximal oxygen consumption by 5-25%
Idiopathic Pulmonary Fibrosis what is?
An inflammatory process involving all the components of the alveolar wall that progresses to gross distortion of the lung architecture.
Etiology of idiopathic Pulmonary Fibrosis speculated theroies
Unknown. May be viral, genetic, or auto-immune. Process seems to begin with inflammation, but then the response to the inflammation continues to generate further abnormalities
patholophysiology of idiopathic pulmonary fibrosist
What happens with the Pulmonary capabilties such as RV, TV, etc..
What do the breathe sounds like??
Can this essentially lead to cor pulmonale
Lung involvement shows patchy focal lesions scattered throughout both lung fields
Lesions first show inflammatory changes and then scar and become fibrotic, distorting the capillary network and alveolar septa.
PFTs Decreased TLC, VC, FRC, and RV Normal or slightly decreased flow rates Diffusing capacity is decreased As the disease progresses the VT decreases and the RR increases
Breath sounds: auscultation reveals bibasilar end-inspiratory dry rales and possibly decreased breath sounds.
CV findings: as the pulmonary capillary bed is destroyed, pulmonary hypertension develops. This can lead to cor pulmonale due to the strain on the right ventricle.
What are some symptoms of idiopathic pulmonary fibrosis think like dyspnea, weight loss, anorexia etc..
Symptoms: Dyspnea Repetitive non productive cough Weight loss Anorexia Sleep disturbances
What is the typical treatment for idiopathic pulmonary fibrosis
Corticosteroids are frequently used in treatment to combat the inflammatory process to help vasodilate I believe.
Supportive measures such as maintaining adequate oxygenation with supplemental oxygen, ventilatory support, and nutritional support.
Bronchiolitis Obliterans what is?
A fibrotic lung disease that affects the smaller airways. It can produce both restrictive and obstructive lung dysfunction
Etiology of Bronchiolitis Obliterans??
Adult form of disease occurs in those ages 20-80
Causes:
Toxic fume inhalation
Viral, bacterial or mycobacterial infectious agents (particularly mycoplasma pneumoniae)
Associated with connective tissue disorders
Related to organ transplantation (graft vs h
Whats the pathophyisology of the Bronchiolitis obliterans “starts with nercosis”
Characterized by necrosis of the respiratory epithelium in the affected bronchioles
Necrosis allows fluid and debris to enter the alveolipulmonary edema and partial or complete obstruction of the airway
With complete obstruction, the trapped air is absorbed and the alveoli collapseatelectasis
Symptoms of the BO what happens to RR, Flow Rate, Lung volume, ??? everything doesn’t decrease.
Diffusing capacity is reduced
Lung volumes may be normal or decreased
RR is increased
Flow rates are frequently WNLs, but may be decreased
What does the Chest X-ray look like with this disease
What is the ABG like??? Areterial blood gas PaCO2 does it increase the arterial PH??
CXR: may show pulmonary edema; bilateral patchy infiltrates
Later in clinical course, a nodular pattern, consistent with fibrotic changes may be seen
ABGs: hypoxemia is present in most patients; An elevated PaCO2 may result in respiratory acidosis
what does the chest sound like in BO
What are the symptoms : hacking???
Breath sounds: Rales and often expiratory wheezing are heard on auscultation. Areas of decreased breath sounds is also common
Symptoms:
Dyspnea
Increased RR
Hacking, non productive cough
What is the treatment for BO????
very similair to idiopathic pulmonary fibrosis??
but watch fluid balance??
Corticosteroids may be used, especially in those cases resulting from toxic fume inhalation, or associated with connective tissue disease
Supportive measures such as supplemental oxygen and maintaining proper fluid balance
What is pneumonia???? what are its two ways to be caught?
An inflammatory process of the lung parenchyma. This inflammation usually begins with an infection of the lower respiratory tract.
Two categories
Community acquired
Nosocomial or hospital acquired
Etiology how does the virus, and community based pneumoia occur???
What percent does a virus affect???
How do humans usally get rid of the illness???
Community acquired pneumonias
Bacteria account for the majority of these pneumonias
Viruses account for about 1/3 of these pneumonias
Although there are many infectious agents in the environment, few pneumonias develop due to the efficient defense mechanisms of the lung
What are the ways that a patient may acquire pneuomia in the hospital??? Think tubes
Hospital acquired pneumonias
Defined as infections in the LRT with an onset of 72 hours or more after hospitalization
Generally occur in the sickest patients
Risk factors: nasogastric tube placement, intubation, dysphagia, tracheostomy, mechanical ventilation, Thoracicabdominal surgery, lung injury, diabetes, h/o smoking
What part of the lungs usally gets infected first with pneumoia, and does it and how does our body combat the pneuomia??
Bacteria and other microbes commonly enter the LRT. Defense mechanisms Cough Bronchoconstriction Angulation of the airways Mucociliary escalator The immune defenses
What is the most common pathway for pneumoia
What does a patient usally present when he or she has pneumoia??
Most common pathways are inhalation and aspiration
Bacterial pneumonias usually have an abrupt onset. Characterized by lobar consolidation, high fever, chills, dyspnea, tachypnea, productive cough, pleuritic pain, and leukocytosis
How does Viral Pneumonia come about????
Does it cause Edema and hemorrhage??
Viral pneumonias first localizes in the destruction of the mucosal surface.
If viral infection reaches the level of the alveoli, there may be edema, hemorrhage, hyaline membrane formation
Viral pneumonia has an insidious onset, patchy diffuse infiltrates, moderate fever, dyspnea, tachypnea, nonproductive cough, myalgia, and abnormal WBC
