RSBI on vent

 Q: If Rapid Shallow Breathing Index (RSBI) is measured while the patient is breathing through a T-piece on ventilator, it would be erroneously? (select one) 

A) lower

B) higher

Answer: A

Any kind of ventilator support such as pressure support, continuous positive airway pressure (CPAP), and even breathing through a T-piece while patient is on a ventilator will erroneously give a lower than actual RSBI. To minimize this error of margin, RSBI should be obtained using a hand-held spirometer attached to the endotracheal tube while a ventilator is on pressure support (PS) of 0 cm H2O and positive end-expiratory pressure (PEEP) of 0 cm H2O, without flow trigger for one minute.

#ventilators

References:

1. El-Khatib MF, Zeineldine SM, Jamaleddine GW. Effect of pressure support ventilation and positive end expiratory pressure on the rapid shallow breathing index in intensive care unit patients. Intensive Care Med 2008; 34:505. 

2. Patel KN, Ganatra KD, Bates JH, Young MP. Variation in the rapid shallow breathing index associated with common measurement techniques and conditions. Respir Care 2009; 54:1462. 

3. Kheir F, Myers L, Desai NR, Simeone F. The effect of flow trigger on rapid shallow breathing index measured through the ventilator. J Intensive Care Med 2015; 30:103. 

4. Desai NR, Myers L, Simeone F. Comparison of 3 different methods used to measure the rapid shallow breathing index. J Crit Care 2012; 27:418.e1.