Respiratory Flashcards
What is inspiratory reserve volume?
The volume that can be inspired over and above tidal volume.
Used during exercise
What is tidal volume?
Volume inspired and expired with each normal breath
What is expiratory reserve volume?
The volume that can be expired after expiration of tidal volume
What is residual volume?
Volume that remains in the lungs after maximal expiration
Cannot be measured by spirometry
What is anatomical dead space?
Volume in conducting airways
What is inspiratory capacity?
TV + IRV
What is functional residual capacity?
Is the volume remaining in the lungs when a tidal volume is expired
ERV + RV
Cannot be measured by spirometry
What is vital capacity or forced vital capacity ?
The volume of air that can be forcibly expired after a maximal inspiration
TV + IRV + ERV
What is total lung capacity?
The sum of all 4 lung volumes
Is the volume in the lungs after maximal inspiration
Cannot be measured by spirometry
What is the forced expiratory volume FEV1?
The volume of air that can be expired in the 1st second of a forced maximal expiration
What do the internal intercostal a do during respiration?
Pull ribs downward and inward
What is the most important muscle for inspiration?
Diaphragm
What is compliance ?
The distensibility of lung and chest wall
What happens to lung compliance in emphysema ?
- Lung compliance is increased
2. Tendency for lung to collapse is decreased
Where are beta 2 adrenoreceptors ?
Lungs
What shifts the oxygen dissociation curve to the right?
- Increase in carbon dioxide
- Increase in temperature
- Increase in H (reduced pH)
- Increase in 2,3 - diphosphoglycerate
What does IPPV do?
- Increase mean airway pressure
- Increase pulmonary vascular resistance and decrease pre load
- Increase ADH secretion, decrease CO, decrease renal blood flow and UO
What is the peak expiratory flow volume?
520-700l/min
What is the total lung capacity?
5-6.5L
What is FRC?
2 - 3L
What is TV?
500 - 700ml
What are central chemoreceptors sensitive to?
Carbon dioxide
What are peripheral chemoreceptors sensitive to?
Oxygen
Where are the peripheral chemoreceptors?
- Aortic body - located in the wall of the arch of aorta
2. Two nodular carotid bodies in left and right common carotid arteries
How much blood volume can the pulmonary vessels accommodates and the normal resting conditions
500 mL
Valsalva manoeuvre
- Expiring forcibly against a closed glottis
- Decrease venous return to right atrium - decrease diastolic filling to right atrium
- Diminished pulse pressure
- Decreased CO
- When sustained - mild tachycardia and rise in diastolic BP
1/2 life of carboxyhaemoglobin in 100% O2
30min