What is the normal Raw value for airway resistance?

What is the normal Raw value for airway resistance?

• A. 0.3-1.0 cmH2O/L/sec
• B. 0.6-2.4 cmH2O/L/sec
• C. 1.5-3.0 cmH2O/L/sec
• D. 2.0-4.0 cmH2O/L/sec

Answer: (B)

Raw measures how much pressure the respiratory system must generate to move a given amount of air through the conducting airways. It’s calculated as Raw = ΔP / V̇, with units of cmH2O per L per second. The normal range for airway resistance is about 0.6 to 2.4 cmH2O/L/s, which reflects a patent, unobstructed airway through typical sizes and ages. Values within this range indicate normal airway patency and typical work of breathing for the patient. Higher values point to obstruction or increased work of breathing (bronchospasm, edema, mucus plugging, external compression), while markedly lower values would be unusual in healthy airways.

Raw measures how much pressure the respiratory system must generate to move a given amount of air through the conducting airways. It’s calculated as Raw = ΔP / V̇, with units of cmH2O per L per second. The normal range for airway resistance is about 0.6 to 2.4 cmH2O/L/s, which reflects a patent, unobstructed airway through typical sizes and ages. Values within this range indicate normal airway patency and typical work of breathing for the patient. Higher values point to obstruction or increased work of breathing (bronchospasm, edema, mucus plugging, external compression), while markedly lower values would be unusual in healthy airways.