Rapid shallow breathing index for weaning context
RSBI Calculator for Weaning Assessment
Calculate the rapid shallow breathing index (RSBI) using respiratory rate and tidal volume in liters. RSBI is commonly used during spontaneous breathing trial and extubation-readiness discussions, with lower values generally being more favorable.
RSBI is helpful, but it is only one tool in the toolbox. Use it alongside cuff leak, mental status, secretion burden, cough strength, hemodynamic stability, acid-base status, and the patient’s current FiO₂ / PEEP requirements before making extubation decisions. In patients with COPD, interpretation can be especially tricky: some patients may generate deceptively low RSBI values because of large tidal volumes and altered respiratory mechanics, so a “good” RSBI should not be treated as automatic proof of extubation success. In higher-risk COPD cases, clinicians may also consider planned post-extubation support such as NIV when appropriate.
Calculator inputs
Enter tidal volume as milliliters (e.g. 400).
What RSBI helps you do
Frame breathing pattern efficiency
RSBI combines respiratory rate and tidal volume into one number to help describe whether breathing is rapid and shallow versus more efficient.
Support weaning context
It can support extubation readiness assessment, but it should always be paired with cuff leak, responsiveness, oxygen needs, secretion burden, and overall trajectory.
Results
How to think about RSBI
RSBI is a quick way to combine respiratory rate and tidal volume into one bedside number. The classic teaching threshold is an RSBI below about 105, but values below roughly 80 are often more reassuring. Higher values can suggest a rapid, shallow pattern that may be less sustainable during weaning.
But RSBI should never be treated like a stand-alone green light or red light. It is one piece of the extubation picture, not the whole picture.
One tool in the toolbox
- • Consider cuff leak if airway edema is a concern
- • Check level of responsiveness and ability to protect the airway
- • Review FiO₂ / PEEP requirements and oxygenation stability
- • Be cautious in COPD: some patients can produce deceptively low RSBI values, so a “good” number does not guarantee extubation success
- • Assess cough strength and secretion burden
- • Review hemodynamic stability and fatigue
- • In selected higher-risk patients, consider whether a planned bridge to NIV after extubation is part of the strategy
- • Use the ABG Analyzer if gas exchange or acid-base status still matters in the decision