RESUMO
OBJECTIVES: This study aimed to assess the diagnostic accuracy and timeliness of using tracheal ultrasound to examine endotracheal tube placement during emergency intubation. METHODS: This was a prospective, observational study, conducted at the emergency department of a national university teaching hospital. Patients received emergency intubation because of impending respiratory failure, cardiac arrest, or severe trauma. The tracheal rapid ultrasound exam (T.R.U.E.) was performed during emergency intubation with the transducer placed transversely at the trachea over the suprasternal notch. Quantitative waveform capnography was used as the criterion standard for confirmation of tracheal intubation. The main outcome was the concordance between the T.R.U.E. and the capnography. RESULTS: A total of 112 patients were included in the analysis, and 17 (15.2%) had esophageal intubations. The overall accuracy of the T.R.U.E. was 98.2% (95% confidence interval [CI]: 93.7-99.5%). The kappa (κ) value was 0.93 (95% CI: 0.84-1.00), indicating a high degree of agreement between the T.R.U.E. and capnography. The sensitivity, specificity, positive predictive value, and negative predictive value of the T.R.U.E. were 98.9% (95% CI: 94.3-99.8%), 94.1% (95% CI: 73.0-99.0%), 98.9% (95% CI: 94.3-99.8%) and 94.1% (95% CI: 73.0-99.0%). The median operating time of the T.R.U.E. was 9.0s (interquartile range [IQR]: 6.0, 14.0). CONCLUSIONS: The application of the T.R.U.E. to examine endotracheal tube placement during emergency intubation is feasible, and can be rapidly performed.