Abstract No. : ABS0814: Comparison of lung ultrasound technique versus clinical method to evaluate the accuracy of positioning of left endobronchial double lumen tube in patients undergoing elective thoracic surgery- a prospective observational study

BACKGROUND & AIMS: Clinical methods like height and gender were found to be inaccurate in predicting the size of double-lumen tube (DLT).Tracheal ultrasonography (TUS) reliably predicts the size of DLT by measuring tracheal diameter. The aim wasto check theaccuracy of ultrasound over clinical methods. METHODS: This study was conducted on 68 patients undergoing elective thoracic surgery requiring one-lung ventilation (OLV) withDLT. The subjects were divided into two groups depending on the prediction of size of DLT by either clinical (Group1) orultrasound method. (Group 2). The transducer was placed perpendicular to skin over cricoid cartilage to measure the transversediameter of the column of air in the cricoid cartilage which denoted the size of the DLT. The primary objective of the study was to assess the accuracy in prediction of size and placement of DLT through various parameters in both clinical andultrasound groups. RESULTS: The accuracy of predicted DLT size between the Group U and Group C was found to be statistically significant (p=0.044). In Group 1, 56% of patients showed a mismatch between the predicted DLT size and the actual size required, while in Group 2, the mismatch was only 32.4%. The accuracy of placement of DLT in the first attempt suggested by adequate lung isolation was also significantly higher (p=0.028) in the ultrasound group compared to the clinical group. CONCLUSION: The size of DLT can be predicted by using clinical parameters but have low accuracy. In our study, the size of DLT was calculated by measuring tracheal diameter using TUS, which significantly improved the selection of appropriate DLT size, avoiding complications.