Comparison of real-time ultrasonography with waveform capnography in verifying endotracheal tube location- An observational study


Article PDF :

Veiw Full Text PDF

Article type :

Original Article

Author :

Tofazzel Haque Sahana*, Tarapada Das, Madhusudan Tiwari, Sabyasachi Das, Sekhar Ranjan Basu

Volume :

11

Issue :

2

Abstract :

Background: Immediate post-intubation confirmation of endotracheal tube requires direct observational or secondary gadgets-dependent measures having variable sensitivity and specificity. In this study, dynamic real-time ultrasonography is used for the evaluation of endotracheal tube. The correlation between the gold standard test(Capnography) and the unconventional test(Ultrasonography) is also evaluated. Materials and Methods: One hundred ASA PS 1, and ASA PS 2 patients were evaluated for endotracheal intubation using real-time ultrasonography. The desired endotracheal intubation was further confirmed by using time capnography. Victorious tracheal intubation was identified using some radiological signs, only one air-mucosa interface with a comet-tail artefact and enhanced posterior acoustic shadowing indicative of endotracheal intubation. Two air-mucosa interfaces with comet-tail artefacts with posterior shadowing were indicative of oesophageal intubation. Results: The mean (SD) ages of the studied patients were 41.25±7.76 Yrs. A total of 87% of patients had endotracheal intubation and 13% had oesophageal intubation based on ultrasonography scan findings. Capnography finding was 91% endotracheal intubations, 9% were true oesophageal. The true positive and true negative rate, positive predictive value and negative predictive values of real-time ultrasonography were 95%, (95% confidence interval (CI) 88% to 98%) 100% (95% CI 62% to 100%), 100% (95% CI 94% to 100%), 69% (95% CI 38% to 89%) respectively. Kappa (k) value was 0.8. Conclusion: Ultrasonography is a portable sensitive screening equipment for ETT position confirmation. There is a strong association between USG findings with time capnography results.  

Keyword :

Real- time USG, Main stream time capnography, ETT position.