Respiratory E1 Flashcards
What kind of pressure must be created in order to move air into the lungs
Negative
- diaphragm moves down, increasing volume
What are the factors that affect diffusion?
- Surface area
- Partial pressure gradient of O2
- Thickness of membrane
- Quality of O2 (molecular weight)
D = (SA x PO2) / (T x square root of molecular weight)
What is the average V/Q of lungs? is perfusion or ventilation higher or lower?
apex of lungs?
Base of lungs?
average = .8L ; perfusion Apex = 2.1L ; ventilation Base = .23:; perfusion
- less in base due to gravity
Why are accessory muscles of inspiration hypertrophied in patients with COPD?
Air trapping and hyper-inflation result in an increased AP diameter of the rib cage and flattening out of the diaphragm. These two changes decrease the efficiency of respiratory muscles as they are no longer in optimal position to aid in respiration.
Is lung perfusion higher at the apex or base? Why?
Perfusion is higher at the base because of gravity
What impact will perfusion have on a recumbent patient?
Recumbent (lying down) patients have decrease in perfusion, which can lead to orthopnea (SOB while lying down)
What are the accessory inspiratory muscles?
- Serratus posterior superior
- Serratus posterior inferior
- Sternocloidomastoid
- Latissimus Dorsi
- Pec Minor
- Pec Major
- Quadratus Lumborum
- Paraspinal(erector spinae)
- Serratus anterior
- Subclavius
What are the primary muscles of inspiration?
- Scalenes: increase intrathoracic volume
- Diaphragm: Primary action is contraction, Secondary action is to stabilize position of the dome of diaphragm
- external intercostals- Internal and external (parasternal fibers) elevate the ribs, increase intrathoracic volume, and stabilize intercostal spaces to prevent inward collapse of thoracic wall
What are the muscles of forced expiration?
- Rectus Abdominus
- External Obliques
- Internal Obliques
- Tranversus Thoracis/Triangularis Sterni
- Internal Intercostals
How is pulmonary emboli diagnosed?
V/Q ratio is messed up; it increases (ventilation > perfusion) and you find this out through the central line
What are the characteristics of an obstructive disease?
- Dyspnea
- increase in the amount of air that stays in the lungs after each breath
- cough with or without sputum
Volume in the lungs at max inflation; sum of VC and RV
Total Lung Capacity (TLC)
Volume of air moved into or out of the lugs during quiet breathing
Tidal Volume (VT)
Volume of air remaining in the lungs after maximal exhalation
Residual Volume (RV)
Max volume of air that can be exhaled from the end-expiratory position
Expiratory Reserve Volume (ERV)
Max volume that can be inhaled from the end-inspiratory position
Inspiratory Reserve Volume (IRV)
Sum of IRV and TV
Inspiratory capacity (IC)
Max volume of air inhaled from the point of max expiration
Inspiratory Vital Capacity (IVC)
Volume of air breathed out after the deepest inhalation
Vital Capacity (VC)
Volume in the lungs at the end-expiratory position
Functional residual capacity (FRC)
Can you explain why asthma and pneumonia are classified differently?
Asthma = caused by inflammation and increased reactivity of smooth muscle of the airways to various stimuli (obstructive) Pneumonia = caused by inflammatory response affecting the parenchyma of the lungs (restrictive)
What are central chemoreceptors sensitive to that will cause breathing?
pH, specifically H+ ions that cross the BBB
Why should a person with COPD be monitored if given supplemental O2?
A patient with COPD, the central breathing system’s chemoreceptors have been shut down. They rely on the peripheral breathing system to stimulate the vagal nerve for breathing. Peripheral breathing system chemoreceptors are sensitive to the PO2. If there is too much O2 in the blood, this results in the loss of respiratory control.
What is the normal partial pressures of O2, CO2, in gas exchange at the alveolar-capillary membrane?
- O2 = 104 mmHg
- CO2 = 40 mmHg
What happens to the alveolar-capillary membrane in pulmonary disease?
The rate of diffusion of molecules decrease, increasing the risk of respiratory acidosis
How does compliance and elastance change in ageing?
- Elastance decreases with age
- compliance increases with age
How does pulmonary fibrosis affect pressure volume curves during breathing?
it shifts it to the right due to increased membrane thickness resulting in less compliance
What are the factors that cause a right shift in the oxyhemoglobin saturation curve?
- increased CO2
- Increased DPG 2,3
- Increased exercise
- Decreased pH
- Increased altitude
- increased temperature
Why would you put someone with a SCI on ice immediately?
- inducing hypothermia causes a shift in the oxyhemoglobin saturation curve; causes a reduction in metabolic demands and there is plenty of curve
What are the factors affecting composition of alveolar gases?
- The quantity and quality of gases delivered to and from the alveoli by ventilation
- The diffusion rate of gases btw the alveoli and pulmonary capillary blood
- The CO or blood flow through pulmonary capillaries, which removes O2 and add CO2 to alveoli
What are the factors that affect chest cage compliance?
- Diameter/ shape of chest
- Height of individual
- Respiratory muscle integrity
- Respiratory muscle innervation obesity
What part of the airways are cartilaginous?
- Bronchi
2. Trachea
What part of the airways have smooth muscle?
- Trachea
- Bronchi
- Bronchioles
- R. Bronchioles
What are the order of airways from largest to smallest?
- Trachea (conducting airways, cartilaginous)
- Bronchi (conducting airways, cartilaginous)
- Bronchiles (conducting airways, membranous)
- R. bronchioles (gas exchange airway, terminal respiratory unit, alveoli present)
- Alveloar ducts (gas exchange airway, terminal respiratory unit, alveoli present)
- Alveolar sacs (gas exchange airway, terminal respiratory unit, alveoli present)
What are the main functioning components of the respiratory system? it plays a major role in the oxygen transport pathway
- inspired O2 and quality of ambient air
- Airways
- Lungs and Chest wall
- Diffusion
- Perfusion
What 5 factors does diffusion of oxygen from alveolar sacs to the pulmonary circulation depend on?
- Area of the alveolar capillary membrane
- Diffusing capacity of the alveolar capillary membrane
- Pulmonary capillary blood flow
- Ventilation
- Perfusion rate
large volumes of fluid can accumulate in the abdominal cavity and significantly compromise cardiopulmonary function to increased intrabdominal pressure on the underside of the diaphragm
Ascites
how readily the elastic forces accept a volume of inspired air
Lung compliance
C = change in volume/ change in pressure
Interstitial pulmonary firbrosis [increases/ decreases] lung compliance. Emphysema [increases/ decreases] lung compliance. Aging [increases/ decreases] lung compliance.
Decreases; increases; increases
ability to respond directly to force and return to its original resting position or shape after the external force no longer exists
elastance
E = change in pressure/ change in volume
This respiratory pattern is characterized by periods of respiration during which the VT starts shallow and gets progressively deeper, and then gets progressively shallower. This shallow-deep-shallow pattern is followed by periods of significant apnea that can last up to 30s or longer, then the cycle starts over. each cycle can take anywhere btwn 30 and 2 minutes or longer.
Cheyne-Stokes respirations
What are possible causes of Cheyne-Stokes respirations?
- strokes
- TBI
- Brain tumor
- carbon monoxide poisoning
- metabolic encephalopathy
- can be seen in healthy pts experiencing first-time high altitude sickness and can be an ADR of morphine admin
A type of labored or hyperventilation characterized by a consistently deep and rapid respiratory pattern
Kussmaul’s respirations
What causes kussmaul’s respirations?
usually seen in late stages of a severe metabolic acidosis such as diabetic ketoacidosis
Respiratory pattern that has a prolonged inspiration phase followed by a prolonged expiratory phase
Apneustic respirations
- long expiratory phase commonly believed to be apneic phases
What causes apneustic breathing?
damage to the upper part of the pons
- contains the respiratory center of the brain
discontinuous, low pitched sounds, predominantly heard during inspiration and indicate secretions in the peripheral airways
crackles/ rales
abnormally prolonged and deep breathing
hyperventilation
reduction in the amount of air entering the pulmonary alveoli which causes an increase in arterial CO2 level
hypoventilation
chest becomes flattened anteriorly with excessive flaring of the lower ribs (supine position), minimal to no upper chest expansion accessory m involvement with outward flaring of the lower rib cage instead. pt breaths into lateral plane of respiration (gravity eliminated) bc the weakened diaphragm and intercostal ms can’t effectively oppose the force of gravity in the anterior plane; used to focus expansion in areas of the chest wall that have decr. expansion (e.g. SCI with atelectasis or pneumonia, assymmetric chest expansion with scoliosis)
lateral-costal breathing
all or part of the chest wall falls in during inspiration, may be abdominal expansion during exhalation, can lead to a flattened anterior chest wall or precuts excavatum
paradoxical breathing (AKA reverse breathing)
a shrill, harsh sound heard during inspiration in the presence of laryngeal obstruction
stridor
high pitched, continuous whistling sound, usually with expiration and related to bronchospasm or other constriction of the airways
wheezing