Background:A limitation of bronchoscopic balloon dilatation (BBD) is that airflow must be completely blocked for as long as possible during the operation.However,the patient often cannot hold his or her breath for a long period affecting the efficacy of the procedure.In this study,we used an extra-small-diameter tube to provide assisted ventilation to patients undergoing BBD and assessed the efficacy and safety of this technique.Methods:Bronchoscopic balloon dilatation was performed in 26 patients with benign tracheal stenosis using an extra-small-diameter tube.The tracheal diameter,dyspnea index,blood gas analysis results,and complications were evaluated before and after BBD.Statistical analyses were performed by SPSS version 16.0 for Windows (SPSS,Inc.,Chicago,IL,USA).Results:Sixty-three BBD procedures were performed in 26 patients.Dyspnea immediately improved in all patients after BBD.The tracheal diameter significantly increased from 5.5 ± 1.5 mm to 13.0 ± 1.3 mm (P ＜ 0.001),and the dyspnea index significantly decreased from 3.4 ± 0.8 to 0.5 ± 0.6 (P ＜ 0.001).There was no significant change in the partial pressure of oxygen during the operation (before,102.5 ± 27.5 mmHg;during,96.9 ± 30.4 mmHg;and after,97.2 ± 21.5 mmHg;P =0.364),but there was slight temporary retention of carbon dioxide during the operation (before,43.5 ± 4.2 mmHg;during,49.4 ± 6.8 mmHg;and after,40.1 ± 3.9 mmHg;P ＜ 0.001).Conclusion:Small-diameter tube-assisted BBD is an effective and safe method for the management of benign tracheal stenosis.