Tubercular tracheobronchial stenosis: When is surgery indicated?
Tracheobronchial stenosis is troublesome long-term sequelae of tracheobronchial tuberculosis (TBTB) which occurs due to fibrosis and consequent stricture formation. Mohan et al conducted a study at Sir GangaRam hospital, New Delhi to evaluate factors effecting surgical outcome in tracheobronchial stenosis.
TB can cause significant obstruction to the airways which results in recurrent infections, pulmonary function derangement and severe limitation of exercise capacity. Hence interventions such as bronchoscopic balloon dilatation, laser fulguration, and silicon stenting, can offer immediate symptomatic relief. Nevertheless, recurrence rate of stenosis after such methods is high for which repeated procedures may be required, hence surgery is considered when repeated interventions fail.
Researchers conducted a retrospective analysis of 20 operated cases of tubercular tracheobronchial stenosis. Left main bronchus (LMB) was the most commonly involved site with an incidence of 80% and the patients were predominantly females (80%). All the patients had invariably undergone balloon dilation with frequency ranging from one to seven.
Out of 16 cases (80%) with LMB involvement, 12 cases underwent lung preserving surgery and rest 4 required complete pneumonectomy in view of completely destroyed bronchiectatic lung. Postoperative complications occurred in five patients most common being prolonged air leak and surgical site infection. At followup none of the patients had recurrence of symptoms. Also FEV1 showed significant improvement in all 16 patients who underwent lung preserving surgery.
Upon analysis researchers found that surgical outcomes were poor in patients who had long duration of symptoms with more than 2 episodes of preoperative balloon dilatations.
The main objectives of tacheobronchial tuberculosis treatment include- eradication of tubercular bacilli and prevention of stenosis. Anti-tubercular treatment is effective in eradicating the bacilli, however, it cannot prevent development of stenosis. From previous studies it was found that oral corticosteroids failed to reduce incidence of stenosis. In recent times several bronchoscopic interventions have emerged as less traumatic and effective measures. Patients may require repeated dilations and this in turn may trigger stenosis hence surgery being considered as a useful therapeutic option.
None of the previous studies evaluated factors determining surgical outcome and predictors of lung preservation surgery. In this study, prolonged duration of symptoms and number of dilatations >2 times was significantly associated with poor surgical outcomes with longer duration of air leak, hospital stay, and need for intercostal drain. Repeated balloon dilatations <4 times was found to be predictive factor for lung preservation surgery in LMB stenosis. Poor prognostic factors include multifocal stenosis and very long stenotic segments.
Authors conclude-"Surgical intervention is safe, feasible and effective in tubercular tracheobronchial stenosis which fail to respond to bronchoscopic interventions".
Source: Pulle MV, Asaf BB, Puri HV, Bishnoi S, Kumar A. Surgical intervention is safe, feasible, and effective in tubercular tracheobronchial stenosis. Lung India. 2021 May-Jun;38(3):245-251. doi: 10.4103/lungindia.lungindia_343_20.
