The rapid shallow breathing index as a predictor of successful mechanical ventilation weaning: clinical utility when calculated from ventilator data

Abstract

OBJECTIVE: The use of the rapid shallow breathing index (RSBI) is recommended in ICUs, where it is used as a predictor of mechanical ventilation (MV) weaning success. The aim of this study was to compare the performance of the RSBI calculated by the traditional method (described in 1991) with that of the RSBI calculated directly from MV parameters. METHODS: This was a prospective observational study involving patients who had been on MV for more than 24 h and were candidates for weaning. The RSBI was obtained by the same examiner using the two different methods (employing a spirometer and the parameters from the ventilator display) at random. In comparing the values obtained with the two methods, we used the Mann-Whitney test, Pearson's linear correlation test, and Bland-Altman plots. The performance of the methods was compared by evaluation of the areas under the ROC curves. RESULTS: Of the 109 selected patients (60 males; mean age, 62 ± 20 years), 65 were successfully weaned, and 36 died. There were statistically significant differences between the two methods for respiratory rate, tidal volume, and RSBI (p < 0.001 for all). However, when the two methods were compared, the concordance and the intra-observer variation coefficient were 0.94 (0.92-0.96) and 11.16%, respectively. The area under the ROC curve was similar for both methods (0.81 ± 0.04 vs. 0.82 ± 0.04; p = 0.935), which is relevant in the context of this study. CONCLUSIONS: The satisfactory performance of the RSBI as a predictor of weaning success, regardless of the method employed, demonstrates the utility of the method using the mechanical ventilator.

Rapid Shallow Breathing Index as a Predictor of Extubation Outcomes in Pediatric Patients Underwent Cardiac Surgeries at King Faisal Cardiac Center

“…This similar study revealed no association between the RSBI measurements and extubation outcomes [ 20 ]. In other studies about pediatric patients in general, they found an association between the measurements of RSBI prior to extubation and the extubation outcomes which is a prediction of extubation success with low RSBI similar to the results in the two hours prior to extubation RSBI measurements in our study [ 9 , 10 , 22 , 23 ]. Unlike our study, some of these studies established a threshold, cut-off point, to predict the successful extubation, but these cut-off points were variable and ranging from 6.7 to 11 [ 9 , 10 , 23 ].…”

“…For pediatric group, same equation for RSBI is used with a correction by weight, and it is usually calculated during a two-hour spontaneous breathing trial (SBT) [ 9 ]. Multiple studies considered RSBI lower than 105 breath/min/L as a predictor for successful extubation in adult group [ 10 - 12 ]. Although RSBI threshold has been calculated and defined for adults, the threshold among pediatric patients still unclear yet [ 5 ].…”

The rapid shallow breathing index as a predictor of successful mechanical ventilation weaning: clinical utility when calculated from ventilator data

“…One interesting finding presented by Souza et al 1 is that even if there is significant difference in the direct comparison of the RSBI obtained by spirometry or directly from the ventilator, the two are very similar in terms of accuracy, which justifies the use of either method. Although we observed a statistically significant difference in the direct comparison of measurement methods, the values obtained in both groups were below 105, which is indicative of successful weaning.…”

“…First, we would like to congratulate Souza et al for their article entitled "The rapid shallow breathing index as a predictor of successful mechanical ventilation weaning: clinical utility when calculated from ventilator data", recently published in the JBP. 1 The subject is of great importance for professionals in the intensive care unit, and the article presents a new tool for the evaluation of critically ill patients on mechanical ventilation.…”

“…Certainly, despite the interesting findings of the Souza et al 1 study, new research demonstrating the effectiveness of the RSBI in different populations or adjusting its values by clinical factors should be encouraged.…”