The Cardiovascular
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Rapid Shallow Breathing Index (RSBI)

Predicts weaning / extubation success from a spontaneous breathing trial.

Rapid Shallow Breathing Index (RSBI)
Respiratory rate
breaths/min
Tidal volume
mL
Complete the fields above to see the result.

When to use

  • Assessing readiness to wean during a spontaneous breathing trial.

Formula

RSBI = respiratory rate (breaths/min) / tidal volume (L). A threshold <105 favours successful extubation.

Pearls and pitfalls

  • Measured on minimal or no support; a single number complements, not replaces, overall clinical assessment.

References

  1. Yang KL, Tobin MJ. N Engl J Med. 1991;324(21):1445-1450.