What is the normal RSBI value?

What is the normal RSBI value?

• A. 90
• B. 120
• C. 135
• D. 105

Answer: (D)

RSBI is the Rapid Shallow Breathing Index, calculated as the respiratory rate divided by tidal volume (f/VT) during a spontaneous breathing trial. It measures how efficiently someone breathes when not assisted. A normal value is about 105 breaths per liter (f divided by VT). Values around 105 indicate a balanced pattern of rate and volume and are associated with a good chance of successful weaning from the ventilator. Higher RSBI numbers mean either a faster rate or a smaller tidal volume (or both), which signals a less efficient breathing pattern and a higher risk of weaning failure. So the normal value among the options is 105.

RSBI is the Rapid Shallow Breathing Index, calculated as the respiratory rate divided by tidal volume (f/VT) during a spontaneous breathing trial. It measures how efficiently someone breathes when not assisted. A normal value is about 105 breaths per liter (f divided by VT). Values around 105 indicate a balanced pattern of rate and volume and are associated with a good chance of successful weaning from the ventilator. Higher RSBI numbers mean either a faster rate or a smaller tidal volume (or both), which signals a less efficient breathing pattern and a higher risk of weaning failure. So the normal value among the options is 105.