CVP exam 3 Flashcards
Where are respiratory neurons located?
Brainstem
What are the fcts. of those neurons?
Set basic drive of ventilation & activation of muscles of respiration
What are the two respiratory centers?
Dorsal and ventral medullary group & pneumotaxic and apneustic centers
The respiratory centers are influenced by? (3 things)
- higher brain centers 2. peripheral and central chemoreceptors 3. peripheral mechanoreceptors
What are the major inspiratory muscles?
Diaphragm & external intercostals
What are the major expiratory muscles?
Abdominals & internal intercostals
Under resting conditions, expiration is passive and is associated with recoil of the lungs? (True/False)
True
What is pleural P?
Negative P between parietal and visceral pleura that keeps lung inflated against chest wall
Where does the alveolar P stands compared to the atmospheric P during inspiration?
Sub-atmospheric (Supra-atmospheric during expiration)
Transpulmonary P peaks at the end of inspiration? (True/False)
True
What 2 forces are opposed during inspiration?
Chest wall F v.s. lung recoil F
É required for ventilation is 3.5% of tot. body É? (True/False)
True
What is hyperventilation?
Pulmonary ventilation > metabolic demand
What is hypoventilation?
Pulmonary ventilation
What’s a pleural effusion?
Collection of large amount of free fluid in pleural space
Surfactant reduces surface tension? (True/False)
True
Only interdependence plays a role in stabilization of alveolar size? (True/False)
False, surfactant also plays a role
What is tidal volume (TV)?
Amount of air moved in or out each breath
What is inspiratory reserve volume (IRV)?
Max. vol. one can inspire above normal inspiration
What is expiratory reserve volume (ERV)?
Max. vol. one can expire above normal expiration
What is residual volume (RV)?
Vol. of air left in the lungs after max. expiratory effort
What is functional residual capacity (FRC)?
Vol. of air left in the lungs after a normal expiration (RV + ERV)
What is inspiratory capacity (IC)?
Max. vol. one can inspire during an inspiration effort (TV + IRV)
What is vital capacity (VC)?
Max. vol. one can exchange in a respiratory cycle (IRV + TV + ERV)
What is total lung capacity (TLC)?
Air in the lungs at full inflation (IRV + TV + ERV + RV)
What diminishes with restrictive lung condition? (3 things)
VC, IRV & IC
There is around 300 million alveoli with a surface area of 150-200 square meter? (True/False)
False, 50-100 square meter
What is the anatomical dead space?
Airways (~150 ml)
What is the physiological dead space?
Anatomical + non functional alveoli
If the rib cage is immobile, how is inspiration possible?
By diaphragmatic breathing
What is transpulmonary pressure?
Measure of the recoil tendency of the lung
Which muscle of respiration is a stabilizer of the lumbar spine?
Transversus abdominis
If the visceral pleura erodes and allows a region of the alveolar space to communicate with the pleural space, what would happen to the functional residual capacity?
Decreased
What is hysterisis?
At the onset of inspiration, lung vol. changes at a slower rate then the pleural P changes
What act as a lubricant between pleura?
Pleural fluid
What effect will histamine binding to H1 receptors have on the airway smooth muscle
Constrict (H2 receptors = dilation)
Most of the recoil tendency of the lung is due to what?
Surface tension forces
What are the pathophysiologic consequences of hyperventilation?
SV & CO decreased; coronary blood flow decreased; repol. of heart impaired; oxyhemoglobin affinity increased; cerebral blood flow decreased; skeletal muscle spasm and tetany; serum potassium decreased
What is the major effect of sympathetic stimulation on airway smooth muscle?
Dilate, most of the effect is indirect via blood borne (circulating epinephrine)
Why is the left ventricular output slightly higher (1%) than the right ventricular output?
Some bronchial artery blood drains into the pulmonary veins
Which volumes or capacities cannot be determined with basic spirometry?
RV; FRC & TLC
What local effect will Prostaglandin E series have on airway smooth muscle?
Dilation (Prostagladin F series = constriction)