tracheal stenosis is the result of abnormal wound-healing processes leading to hypertrophic scar formation and obstruction of the airway lumen by excess granulation tissue. This process is progressive so treatment and prevention is essential. Resection-anastomosis of the trachea is becoming the standard of care in many centers and gives the most consistent results in both adult and pediatric patients. But recurrence stenosis, re-granulation and re-inflammation are probable. This study aimed to assess the efficacy of systemic prednisolone on prevention of recurrent tracheal stenosis after surgery.

Tracheal stenosis affects 4-13% of adults and occurs in 1-8% of neonates after prolonged intubation in United States. The causes of adults' tracheal stenosis include trauma, chronic inflammatory diseases, benign neoplasm, malignant neoplasm and collagen vascular diseases. The most common cause of tracheal stenosis continues to be trauma, which can be internal (prolonged endotracheal intubation, tracheostomy, flame, burn injury) or external (neck trauma). Approximately 90% of chronic subglottic stenosis in children and adults results from endotracheal intubation or tracheostomy and about 10% results from other causes.

The resection anastomosis is the most effective treatment to cure this condition. The other treatments are mechanical dilation (dilators, rigid bronchoscopes), stents, laser co2, diode, and cold knife. But they are not as effective as resection anastomosis. Rigid bronchoscopes or dilators may shear the mucosa leading to further damage. Resection of all damaged segments of the airway, approximation and anastomosis of the two intact ends by means of fine synthetic absorbable sutures with minimum tension. Steroids with anti-inflammatory effect widely use as first line therapy for this condition.

Patients who underwent resection anastomosis during 2014-2016 for treatment of post-intubation tracheal stenosis will be included in this study. Systemic prednisolone will be used for treatment and prevention of recurrent tracheal stenosis in post-operative patients. Post-operative patients will divide in two groups, one of them will receive prednisolone and the other will receive placebo for 30 days. The results will be compared by bronchoscopy (FOB or rigid) after 30 days.

Inclusion criteria:

1. Post-operative resection anastomosis patients.
2. Age more than 10 years old.
3. no severe tension in surgery by the opinion of surgeon.

Exclusion Criteria:

1. Pregnancy
2. History of significant medical condition not controlled by medicines. Ex: cardiovascular diseases, endocrine impairments and etc.
3. Weight is ≥200% ideal body weight
4. Severe chronic liver disease
5. immunosuppression including HIV+ status, history of bone marrow or solid organ transplantation, current malignancy, neutropenia
6. Fungal systemic infection