Testing the prognostic value of the rapid shallow breathing index in predicting successful weaning in patients requiring prolonged mechanical ventilation.

OBJECTIVE: The study objective was to assess the prognostic value of the rapid shallow breathing index (RSBI) in predicting successful weaning of patients from prolonged mechanical ventilation (PMV) in long-term acute care (LTAC) facilities. The RSBI predicts successful ventilator weaning in acutely ill patients. However, its value in PMV is unclear.

METHODS: A retrospective cohort study of patients receiving PMV in LTAC facilities was performed. RSBI was measured daily, with weaning per protocol. Initial, mean, and final RSBI; RSBI ≤ 105; rate of change; and variability were assessed.

RESULTS: Twenty-five of 52 patients were weaned from PMV. Only the mean RSBI and the RSBI on the last day of weaning predicted success (78.7 ± 14.2 vs 99.3 ± 30.2, P = .007; 71.7 ± 31.2 vs 123.3 ± 92.5, P = .005, respectively). RSBI variability and rate of change were different between groups (coefficient of variation, .37 ± .12 vs .51 ± .30, P = .02, rate of change: -3.40 ± 9.40 vs 4.40 ± 11.1 RSBI points/day, P = .005, weaned vs failed).

CONCLUSION: Although isolated RSBI measurements do not predict successful weaning from PMV, RSBI trends may have prognostic value.