respitory how much someone breaths Flashcards
What is tidal volume (TV) and what factors affect respiratory capacity?
Tidal volume (TV) is the amount of air moved into and out of the lungs with each breath during normal quiet breathing, approximately 500 ml (about a pint). Factors that affect respiratory capacity include size, sex, age, and physical condition of the person.
: What is inspiratory reserve volume (IRV)?
: Inspiratory reserve volume (IRV) is the amount of air that can be forcibly inhaled above the tidal volume. It is typically around 3,100 ml, and it represents the extra air a person can inhale after a normal tidal breath.
What is expiratory reserve volume (ERV)?
Expiratory reserve volume (ERV) is the amount of air that can be forcibly exhaled beyond the normal tidal expiration. It is typically around 1,200 ml, representing the extra air a person can exhale after a normal breath.
What is residual volume (RV) and why is it important?
Residual volume (RV) is the amount of air that remains in the lungs after the most strenuous expiration and cannot be voluntarily expelled, approximately 1,200 ml. It is important because it allows continuous gas exchange between breaths and helps keep the alveoli open (inflated).
What is vital capacity (VC) and how is it calculated?
Vital capacity (VC) is the total amount of exchangeable air in the lungs, typically 4,800 ml in healthy young men and 3,100 ml in healthy young women. It is the sum of the tidal volume (TV), inspiratory reserve volume (IRV), and expiratory reserve volume (ERV)
What is dead space volume and functional volume?
Dead space volume refers to the air that enters the conducting zone passageways but doesn’t reach the alveoli for gas exchange. It is about 150 ml during a normal tidal breath.
Functional volume is the air that actually reaches the respiratory zone and contributes to gas exchange. It is about 350 ml during a normal tidal breath.
How are respiratory capacities measured and what can spirometry reveal?
Respiratory capacities are measured with a spirometer, which tracks air volume changes as a person breathes. The spirometer helps evaluate respiratory function and monitor respiratory diseases. For example:
In pneumonia, inspiratory reserve volume (IRV) and vital capacity (VC) decrease due to inspiration obstruction.
In emphysema, expiratory reserve volume (ERV) is much lower than normal, and residual volume (RV) is higher due to difficulty in expiration.
What are the different respiratory actions and their purposes?
Cough: Deep breath, closing the glottis, forcing air upward against the glottis, followed by a sudden blast of air. Clears lower respiratory passageways.
Sneeze: Similar to a cough but directs air through the nasal cavity. The uvula closes the oral cavity, routing air through the nasal passages to clear the upper respiratory passages.
Crying: Inspiration followed by short expirations, an emotionally induced mechanism.
Laughing: Similar to crying in terms of air movement; also an emotionally induced response.
Hiccups: Sudden inspirations caused by spasms of the diaphragm, often due to irritation of the diaphragm or phrenic nerves. The sound occurs when the inspired air hits vocal folds of the closed glottis.
Yawn: Very deep inspiration with wide-open jaws, ventilating all alveoli, some of which may remain collapsed during normal quiet breathing.
What are bronchial sounds and vesicular sounds?
Bronchial sounds are produced by air rushing through the large respiratory passageways (trachea and bronchi). They are louder and harsher.
Vesicular sounds occur as air fills the alveoli, producing soft murmurs that resemble a muffled breeze. These sounds are softer and quieter than bronchial sounds.
What are abnormal respiratory sounds and what causes them?
Crackle: A bubbling sound, often caused by fluid (like mucus or pus) in the lungs.
Wheezing: A whistling sound caused by narrowed airways (often due to conditions like asthma).
Rales: Abnormal bronchial sounds caused by mucus or exudate in the lung passages or thickening of the bronchial walls.
