Exam 3: Wk 11: Obstructive/Restructive Lung Dysfunction Flashcards
How does the brain control ventilation?
Feedforward - estimates how much ventilation should be required
Output - motor activity to mm of inspiration
Causes of Dyspnea
Ventilatory pump failure = hypoxia hypoxic (hypoxemia)
Cardiac pump/supply lines- ischemic hypoxia (ischemia) (HA/Strokes)
Bloods oxygen carrying capacity - anemic hypoxia (anemia)
Leading cause of morbidity and mortality in adults in western civilization
Ischemic hypoxia
3 main causes of breathing disorders
- damage to the brain stem
- difficulty inhaling (restrictive)
- difficulty exhaling (obstructive)
Restrictive disease
Breathing impaired AS IF movement of chest is restricted
- normal strength, but chest too stiff
- normal stiffness, but too weak muscles
- all spirometry volumes are reduced
Obstructive Disease
Breathing impaired AS IF airways obstructive
- SOB due to difficulty exhaling
- increased FRC
- increased diameter of chest (barrel chest)
Tip to help people w obstructive disease breathe better
Long and slow breaths
Two basic causes of obstructive disease
- Increased airway resistance (asthma)
- Decreased elastic recoil
Emphysema
Loss of elastic recoil so you can’t get all the air out of lungs
Can have some airway obstruction
Pressure builds up in alveoli and its walls become damaged
CF can result in obstructive diseases like _____ or ______
Bronchiectasis or chronic bronchitis
Obstructive disease : equal pressure point
Point in airway anatomy where outside compressive pressure equals inside elastic pressure
- should occur in larger airways with cartilaginous rings
W obstructive disease, there’s loss of pressure moving air through obstruction moves the equal pressure point distally so when they cough, its less effective
T or F: COPD is a category of disease, not a specific disease
True
4 diseases that make up COPD
ABCE
Asthma
Bronchietasis
Chronic bronchitis
Emphysema
Describe the type of hypoxemia:
SOB w normal sP02 and PO2,
normal blood flow
Inadequate O2 carrying capacity
Anemic hypoxemia
Describe the type of hypoxemia:
SOB w normal sP02 and PO2,
inadequate blood flow
Normal O2 carrying capacity
Ischemic hypoxemia
Describe the type of hypoxemia:
SOB w decreased sP02 and PO2,
normal blood flow
Normal O2 carrying capacity
Hypoxic hypoxemia
Pathophysiology of emphysema (how it develops)
Smoking —> respiratory bronchiolitis
Signs and symptoms of emphysema
- barrel chest
- emaciated
- hypertrophy SCM and scalenes
- tripod position
- prolonged emphysema
Medical and surgical management of emphysema
Bronchodilators
Lung volume reduction surgery : restores biomechanics of breathing by removing poorly functioning lung tissue
Chronic Bronchitis
Excessive sputum production on most days for at least 3 months of the year for at least 2 consecutive years
- impaired mucus clearance
Airway gets smaller
Blue bloater
Chronic bronchitis - overweight and cyanotic
- cant get CO2 out
Pink puffer
Emphysema
Bronchiectasis
Chronic and permanent dilation of bronchi due to inflammation or infection
- copious amounts of foul smelling sputum
- dilated or obliterated bronchi in dependent airways
S & S Bronchiectasis
- chronic cough
- coughing blood and a lot of mucus
- abnormal wheezing
- SOB
- chest pain
- fatigue
- bad breath odor
- BLUE
- weight loss
- thickening of skin under nails or toes
Medical management of Bronchiectasis
Antibiotics, airway clearance, surgical removal of nonfunctioning tissue
What is described as inflammation of bronchial walls without an increase or change in bronchial wall diameter?
Bronchitis - no change in wall diameter, the inflammation narrows the airways
What happens to the walls in Bronchiectasis
The walls are dilated and eventually destroyed
Is co2 acid or base
ACID (volatile acid)
Normal mechanism of ventilation drive
Negative feedback loop between pH and CSF and ventilation
Response of ventilation to decreased pH
Ventilation increases and if chronic, kidneys respond to eliminate fixed acid
Ventilation response to increased pH
Ventilation is slowed
- CO2 accumulates
- pH is normalized
- if chronic, kidneys and buffering systems respond
Effect of CO2 on the brain
- high CO2 will depress cerebral function
*giddy to somnolent to unconscious to DEAD
How much O2 does normal air have? How about FIO2?
Normal air has 21% oxygen
FIO2 = .21
How is FIO2 increased?
Increasing flow rate or % O2
Higher ventilation = ______ PO2 and ____ PCO2
Is this good or bad
Higher PO2
Lower PCO2
This is good :)
High ventilation has ____ PO2 and _____ PCO2
Low PO2
High pco2
Atmosphere has ___ PO2 and ____ PCO2
High PO2
Low PCO2
High ventilation makes alveoli like atmosphere or venous blood? Hb low ventilation?
High - atmosphere - freshhhh
Low - venous blood - stale
what is the primary determinant of oxygenation of the blood ?
V/Q
Vq ratio
Increasing V/Q does what it PaO2 and PaCO2
Increases PaO2 and lowers PaCO2
Decreasing V/Q does what to PaO2 and PaCO2
Decreases PaO2 and increases PaCO2
What’s the optimal V/Q
.8
What is carried w ventilation? What is carried with perfusion? And to where?
Ventilation - O2 into alveoli
Perfusion - O2 away from alveoli to be used by the body
Low V/Q analogy
bus leaves half empty - hypoxic hypoxia
- low ventilation results in low PaO2 and unloaded Hb leaving capillaries
High V/Q analogy
One bus and 1000 ppl wanting to board
*high ventilation causes PO2 to rise and PCO2 to fall
V/Q at resting conditions slow ventilation and slow pulmonary blood flow unit
Slow ventilation 4L/min
Slow pulmonary blood flow 5L/min
V/Q during exercise
Pulmonary blood flow increase 4-5x resting blood flow
Too much V/Q - why is it bad
Waisting energy on breathing - wasted ventilation so there’s less O2 for the rest of the body and arterial CO2 falls and respiratory alkalosis can occur
Slower blood flow ___ PaO2
Increases
If cardiac output is low and V/Q is normal what happens to PaO2 and what type of hypoxia is it?
May have high PaO2 and would result at a tissue level of ISCHEMIC HYPOXIA and cellular injury
If cardiac output is normal and V/Q is low, what happens to PaO2 and what type of hypoxia is it
PaO2 becomes low and results in hypoxic hypoxia
What do pulmonary functional tests look at?
TV , IRV, ERV, VC, some wash out helium or nitrogen
Gas Flow Rate
Looks at the volume of flow to see if there’s early airway closure or collapse as is typical with COPD (decreased flow rate)
Flow volume loop interpretation
Low volume - restrictive disease
Peaked slope = restrictive
Scooped out = obstructive
DLCO - diffusion capacity of lung
Ability of lungs to transfer gas from inhaled air to the RBC in the pulmonary capilalries
Factors that decrease diffusion
Anemia
Increased diffusion distance
Decreased exchange area
Poor perfusion
Norm for FEV1/FVC
> .8 or 80%
Restrictive lung disease definition
Difficulty breathing O2 in due to decreased lung compliance or impaired ability of thorax to expand
Main characteristics of RDL
Decreased pulmonary compliance
Increased work of breathing
On PFT all lung volumes and capacities are decreased
What type of cancer is leading cause of death in US
Lung cancer :(
Pulmonary Fibrosis
Inflammatory process of alveolar wall
- patchy focal infiltrates thought the lung, may become fibrotic or scarred
Pulmonary Fibrosis
- ABGs: pO2 decreased/ pCO2 normal
- decreased breath sounds
- cor pulmonary, clubbing, cyanosis
- nonproductive cough
- weight loss
Tx for pulmonary fibrosis
Corticosteroids only in inflammatory stage, O2, nutrition, pulmonary rehab
Pneumonia is inflammation of
Parenchyma
Signs and symptoms of Pneumonia
Crackles over consolidation
Infiltrate on CXR
Hyporesonance on percussion
SOB
Tachypnea
Pressure change of obstructive vs restrictive
Obstructive: greater pressure change REQUIRED
Restrictive: greater EFFORT to achieve pressure change
Obstructive vs restrictive lung volumes
Obstructive: increased FRC
Restrictive: all volumes decreased
Causes of Obstructive vs Restrictive
Obstructive: physical obstruction, lack of elastic recoil
Restrictive: stiffness, weakness, edema
Restrictive Disease Viscous Cycle
Disease —> dyspnea —> poor posture & chest wall mobility —> disuse —> disease
Upper Respiratory Infection
Cold, influenza
- can lead to LRI
Lower Respiratory Infection
Pneumonia - inflammation and consolidation of lung tissue
Abscesses
Bronchitis/Bronchioltis
Pneumonia
Bacterial divided into lobar and bronchopneumonia
Atypical Pneumonia
Caused by micro plasma, viruses, chlamydia
Walking Pneumonia
Infection by mycoplasma pneumonia
- watery sputum and substernal burning with coughing
- pt does not feel ill and can function to a large degree
- requires antibiotics that does not act on cell walls as mycoplasma do not have cell walls
Viral Pneumonia
Fever, headache, muscle ache, dry cough, dry hacking, no sputum
Lobar Pneumonia
When pneumonia is limited to a lobe or segment of the lung
- lower lobe mostly affected DUH
Bronchopneumonia
Widespread inflammation of distal airways
Lung Abscesses
Aspiration of infected material due to dysphagia
Epiglottitis
Life threatening infection of young children
*vaccine now so its less common
Croup
Upper airway infection that blocks breathing and has a barking cough
- inspirations strider, cough
Respiratory Synctial Virus RSV
Cause of Viral pneumonia in children under 2
- passed due to lack of handwashing
Walking speeds for ADLs and crossing street and such
Look in the last lecture idk but pretty fast ig
