PREDICTING POST-EXTUBATION RESPIRATORY FAILURE AFTER MYOCARDIAL INFARCTION USING THE RAPID SHALLOW BREATHING INDEX AND LUNG ULTRASOUND SCORE

Abstract

The Rapid Shallow Breathing Index (RSBI) has been hypothesized to have discriminating power for categorizing patients at higher risk of post-extubation respiratory failure (RF). Hence aim of this study was to determine the predictive value of RSBI for post-extubation RF in patients after acute myocardial infarction (AMI). Consecutive, intubated patients admitted post-revascularization were included. RSBI and lung ultrasound score (LUS) were measured and post-extubation RF within 48 hours was recorded. RF was observed in 36.3% (78/215) patients. For the prediction of RF, RSBI and LUS had area under the curve of 0.670 and 0.635, respectively. The sensitivity, specificity, negative predictive value, and positive predictive value of RSBI >50.5 were 75.6%, 54.7%, 79.8%, and 48.8% respectively, while, the accuracy measures for the combination of RSBI with LUS >1.5 were 44.9%, 84.7%, 73.0%, and 62.5% respectively. Combined RSBI and LUS measured during spontaneous breathing trial in patients after an AMI, have high predictive abilities for identifying post-extubation RF.