pulmonary pathophysiology Flashcards
week 4
pathophysiological differences
obstructive
restrictive
obstructive = impaired FLOW of air
Restrictive = impaired VOLUME of air
TLC
total lung capacity
FVC
force vital capacity
FEV1
force expiratory volume in 1 second
pulmonary function tests (PFTs)
airway integrity is assessed by analyzing
lung volume, diffusion capacity
pulmonary function tests (PFTs)
body plethysomography
airtight chamber; pressure at the airway (mouth piece) + chamber is measured
- used commonlly in research
barriers–> claustrophobia
pulmonary function tests (PFTs)
incentive spirometer
very common and easy to perform bedside
- used after surgery to encourage deep breathing
nursing or respirtatory therapists work with these
Diffusion capacity of lungs for carbon monoxide (DLCO)
ease of transfer for CO moleucles from alveolar gas to Hgb of RBCs in the pulonary circuit
volume, amount of time and how much pressure it is having to overcome
normal DLCO
abdnormal DLCO
normal: >75% of predicted (25-30 mL/min/mmHg)
abnormal: decreased Hgb; increased thickness of alevolear capillary membrane; decreased surface area available for diffusion
mild = <75%-60%
moderate= 60-40%
severe <40%
restrictive lung disease (RLD)
lung expansion is restricted, adn therefore the volume of air or gas moving in and out of the lungs is decreased
- chest wall or lung compliance, or both is decreased
- takes a greater transpulmonary pressure to expand the lung to a given volume in a person with decreased lung compliance
this means the patient has to work harder just to move air into the lungs
restrictive lung dysfunction: impaired ventilation –> decreases volume and capacities resulting in
- decreased inspiratory reserve volume
- decreased expiratory reserve volume
- decreased total lung capacity
- decreased diffusion capcity of lungs for carbon monoxide (DLCO)
what are the 3 charcteristsics of RLD you would assess
- lung volume
- lung compliance
- work of breathing
RLD - lung volume
- decreased TLC
- FEV1/FVC ratio is preserved
capacity is lower but still able to breath out 1/2 of inspired air at 1 second
RLD- lung compliance
RLD - work of breathing
3 symptoms of RLD
dyspnea
- typically manifests with exercise, but as RLD progresses dyspnea at rest may also be experienced
irritating,dry, and non productive cough
wasted, emaciated appearance these patients present ast he disease progresses
- work of breathing increased as muc has 12fold over normal, these individuals are using caloric requirements similar to those necessary for running a marathon 24 hrs a day
- breating is hrad work and eating makes breathing mroe difficult
- cachectic- continual weight loss cycle
supportive measures for treatment of restrictive lung dysfunction
- supplemental O2
- antibiotic therapy for secondary infection
- interventions to promote adequate ventilation
- interventions to prevent accumulation of secretions
- good nutritional support
hypoxemic state
seen in RLD
PaO2 < 80 mmHg
- lung scarring
- capillary fibrosis –> pHTN –> R CHF
- widened interstitial spaces –> inability to support alveoli
- collapsed alveoli (end-inspiration)
what is normal intrapulmonary shunting
shunting = cutting off blood flow from one area and moving it to another. think of frost bite
normal = anatomic shunting
- blood flows from R to L side of heart, bypassing capillary exchange
what is abnormal intrapulmonary shunting
abnormal= capillary shunting
- blood flows from R to L side of heart by way of pulmonary capillaries
intrapulmonary shunting overloads the pulmonary system and what occurs
side18
pulmonary hypertension (pHTN)
resting PAP >25 mmHg; exertional PAP >30 mmHg
what are the groups of pHTN per WHO
Group 1: pulm. arteries are narrow/thick/stiff –> R CHF
Group 2: pulm. arteries are not as narrowed; back up of blood –> L CHF
Group 3: due to an onstructive or restrictive pattern; arteries constrict –> shunting to more ventilated alveoli –>pHTN
Group 4 chronic thromboembolic pHTN; undissolved clot –> scar tissue w/in pulmonary blood vessels –> decerase bld flow –> increase work on R heart
who severity classification
class I
Class II
Class III
Class IV
primary risk factors for RLD
- tobacco use/exposure
- occupational exposure (pneumocroniosis)
- radiation and chemotherapy
flow-volume loop
- smaller lung volumes (RV, TLC)
- flow rates (PEF) is maintained
flow rates (PEF) equation
PEF = max E-flow at any point during FVC
clincial presentation: restrictive lung disease
subjective data
- dyspneic
- muscle wasting (have they told you they have lost weight, can you see their ribs)
- cyanosis, clubbing
- non productive dry cough
clincial presentation: restrictive lung disease
objective data
- hypoxia
- lung auscultation:
decreased breath sounds
dry cackles (rales) - PFT (decreased TLC/DLCO)
underlying etiologies of RLD:
interstitial:
environmental:
infection:
neoplastic:
pleural:
CV:
neuromuscualr:
interstitial: pulmonary fibrosis, sarcoidosis, bronchiolitis obliterans
environmental: pneumoconiosis, scilicosis, asbestosis
infection: pneumonida (type 5)
neoplastic: bronchogenic carcinoma
pleural: pleural effusion, atelectasis, ARDS
CV: pulmonary edema, pulmonary embolism
neuromuscular: (not tested on for exam 1)
Rheumatoid arthritis - affect on lungs
7 things
- one of the connective tissue causes of RLD
RA can affect the lungs in 7 different ways
- pleural involvement
- pneumonitis
- interstitial fibrosis
- development of pulmonary nodules
- pulmonary vasculitis
- obliterative brohnciolitis (OB)
- increased incidence of bronchogenic cancer
systempic lups erythematosus (SLE)
- chronic inflammatory connectibe tissue disorder
- in 50%-90% of cases involves the lungs or pleura
- the most common lung involvement is pleurisy, often with the development of small bilateral exudative pleural effusions that may be recurrent
- associated with pericarditis –> lead to fibrous pleuritis
PT’s roles for oyxgen in those with autoimmune or different lung diseases
- monitor SpO2
- discuss need for supplemental O2
- request MD orderfor O2 (should include titration parameters)
- knowing how much O2 is left in tank during treatmnt session (tank: treatment duration)
what is the equation to figure out how much supplemental oxygen is left
duration = cylinder factor X tank pressure/ flow rate
values will be given but an example looks like
how much is in the tank - how much is left in the tank
most common obstructive lung dysfunction (OLD)
- COPD (3rd leading cause of death worldwide)
what is obstructive lung dysfunction (OLD) patient presentation
airflow obstruction problems
1. retained secretions
2. inflammation of the mucosal lining of airway walls
3. bronchial constriction related to increased tone or spasm of bronchial smooth muscle
4. weakend structural support of the airway walls
5. alveolar sac destruction and alveolar sac overinflation with surfactant destruction
associated impairements of ostructive lung dysfunction (OLD)
- physical changes (like COPD not just in the lungs but within entire MSK system)
- chronic inflammation causes structural changes and narrowing of the small airways within the individuals lungs
- that inflammation destroys the lung parenchyma nad leads to loss of alveolar attachments tot he small airways, decreasing the lungs ability for elastic recoil
- as teh lungs ability for elastic recoil diminishes, the small airways are unable to remain open during expiration, 3 which minimizes teh lungs ability to perform gas exchange necessary for oxygen perfusion
this loss of elastic recoil leads to what?
the loss of elastic recoil in ostructive lung dysfunction leads to
- chronic lung hyperinflation, cuasing the rib cage to take on a barrel shape, decreasing the ribs’ ability to move in the normal pump handle motions
- as teh rib cage chages shape, teh diaphragm begins to flatten, there is a loss of sarcomeres, and a change in the length-tension relationship of the muscle.
slide 39 need to finish
OLD - what is presenting with the patient
incomplete emptying –> loss of alveolar elasticity –>
air trapping
obstructive lung dysfunction (OLD)
what physiologic changes occur
- chronic inflammation
- narrowing of bronchial lumen –> mucus collection
- increased resistance to each expiratory attempt
- poor gas exchange
- V/Q mismatch
- hypoxemia (< pO2; > pCO2)
- increased type II fibers –> chronic anaerobic state
charactertic of cells of OLD
slide 43
primary risk factors for obstructive lung dysfunction
- inhalation (smoking)
- genetics (cystic fibrosis)
what is 20 pack years?
slide 45
PFT interpretation: obstructive
global initiative for COPD (GOLD) criteria
typical obstructive presentation:
- reduced FEV1
- reduced FEV1/FVC ration
- gold criteria (stage I-IV)
what is the flow-volume loop for obstructive dysfunction
- deceased flow rates
- scooped out appearance
- deficient PEF (peak expiratory flow)
obstructive has a left shift
clinical presesntation: obstructive lung disease
chart review/subjective data
- primarily complain of dyspnea
- CXR: hyperinflation, flattened diaphragm (icnrease TLC/RV)
- horizontal rib cage
- barrel-shaped thorax
- kyphosis
clinical pressentation: obstructive lung dysfunction
objective data
- hyperresonance on mediate percussion
- abnormal diaphragmatic excursion (flattened)
- hypertrophic accessory mm
- PFT: decreased FEV1: decrease FEV1/FVC ratio
underlying etiologies of obstructive lung disease
- emphysema
- chronic bronchitis
- asthma
- bronchiectasis
- cystic fibrosis
emphysema (pink puffer)
- increase CO2 retention (pink)
- hyperresonance on chest percussion
- minimal cyanosis
- speaks in short jerky sentences
- dyspnea
- use of accesssoyr muscle to breateh
- orthopneic
- barrel chest
- exertional dyspnea
- purse lip breathing
- prolonged expiratory time
- think appearance
- anxious
chronic bronchitis (blue bloater)
- airway flow problem
- color dusky to cyanotic
- recurrent coug hand increase sputum producin
- hypoxia
- hypercapnia (increase pCO2)
- respiratoyr acidosis
- increase HgB
- increase RR
- exertional dyspnea
- increased incidence in smokers
- digital clubbing
- cardiac enlargement
cystic fibrosis (CF)
- numerous mutations are responsible for CF variatiosn and severity
- either increased production of secretions or failure to clear secretions at a nearly age accounts for the mucus accumulation seen in bronchial regions and in bronchioles
symptoms of CF
- salty tasting skin
- frequent lung infections
- wheezing and or dyspnea
- poor growth and slow weight gain despite a healthy diet
- frequent greasy, bulky stools and or difficult bowel movements
PT’s role in CF
- lung auscultation
- monitoring vitals (SpO2)
- secretion clearance
- controlled breathing
- ambulation
- endurance and strength training
- energy conservation techniques
- edu: weight monitoring, secretion color, dyspnea, O2
edu ex: dyspnea put pulse ox on and have them see they are not short of breath even if they feel like they are
education on energy conservation
remember and practice the 4 P’s
- prioritize
- plan
- pace
- position
energy conservation handout found in week 4
stop and rest before you get tired. plan rest times. rest often
what two organs help with pH balance
kidneys and lungs can help balance when the pH is off
