Novel Respiratory Breath Hold Index: A Predictor for Successful Extubation in Mechanically Ventilated Patients, a Pospective Cohort Study

Background: Liberation from mechanical ventilation is a major objective in critically ill patients. Various criteria for extubation are used with different success rates. We developed a novel, simple bedside maneuver and index that involves measuring breath-hold duration and forced vital capacity (FVC). We named it the Respiratory Breath Hold Index (RBHI). Methods: We enrolled 225 mechanically ventilated intensive care unit (ICU) patients who were candidates for extubation. At the end of a spontan eous breathing trial (SBT), and just prior to extubation, patients were asked to hold their breath and perform a stalked FVC maneuver. The ability to perform a breath-hold maneuver and its duration were recorded and compared with a standard SBT. Results: 171 patients (76%) were successfully extubated, while 54 patients (24%) failed extubation. A successful SBT alone did not predict extubation, as 80.1% of passed SBT and 81.5% of failed SBT patients were extubated successfully (p = 1.00). However, a higher RBHI, together with the ability to hold breath and breath-hold duration, was highly associated with a successful extubation (p < 0.0001). Logistic regression analysis showed that RBHI over 3 was correlated with higher rates of successful extubation (OR 4.252, p < 0.001). Overall, 89% of patients who passed SBT and were able to hold breath were successfully extubated. (p < 0.0001). Whereas, among patients who passed SBT but failed to hold breath, only 24% were successfully extubated (p < 0.0001). Conclusion: Higher RBHI, together with the ability to hold a breath just prior to extubation in mechanically ventilated patients, is more sensitive and specific, and may be superior to standard SBT in predicting a successful extubation.