Background: Rapid shallow breathing index (RSBI) has become widely used in practice and research with varying success. However, studies have demonstrated that rapid shallow breathing index (RSBI) rate or a measure of change of RSBI over time, may offer more predictive value than its RSBI. This study evaluated the accuracy of rapid shallow breathing index and rapid shallow breathing index rate in predicting weaning success in pediatric patients who underwent cardiac surgery.
Method: This is a prospective cohort study done at the Philippine Heart Center Pediatric Critical Care Units from January 11, 2017 - March11, 2017. Admitted pediatric patients who underwent cardiac surgery were enrolled. After the surgery, once patients are ready for weaning, the study investigator obtained respiratory variables from the mechanical ventilator monitor. RSBI1 was taken during the first minute of spontaneous ventilation and RSBI2 was measured after 30 minutes of spontaneous breathing. Patients who were able to maintain spontaneous breathing for 48 hours after extubation were labeled as weaning success and those patients who required reintubation or noninvasive ventilation after extubation and is not able to remove it after 48 hours extubated. Infants requiring reintubation less than 48 hours after extubation was also labeled as weaning failure.
Results: A total of 58 patients were included in the study, 55 patients (93%) were successfully weaned and 4 patients (7%) failed weaning and were reintubated and required mechanical ventilation in less than 12 hours post-extubation. The weaning failure group showed a higher RSBI (mean 30 +27.1) and RSBI rate (mean 36.4 +40.8), respectively. Twenty patients have RSBI >17, 18 patients were successfully extubated and 2 patients failed the weaning. Thirty-eight patients have RSBI <17 with a sensitivity and specificity of 50% and 66.6% respectively and positive predictive value and negative predictive value were 10% and 94.74%, respectively. RSBI rate of >18 have sensitivity and specificity of 50%. Likewise, the positive predictive value and negative predictive were 6.9% and 93.10%, respectively. RSBI has slightly higher accuracy value at 65% compared 53.94% of RSBI rate (p-value 0.419) in predicting weaning success among post-cardiac surgery pediatric patients.
Conclusion: RSBI has higher accuracy value compared to Rapid Shallow Breathing Index rate in predicting weaning success among post-cardiac