ABSTRACT
We describe a case series of 35 patients with either benign (14) or malignant (21) tracheal stenosis who were treated using a novel silicone stent, the HCPA-1, designed to prevent migration. Between March 2001 and September 2008, 13 women and 22 men received 41 HCPA-1 stents. The median duration of stenting in benign cases was 457 days (range, 4-2,961 days). Successful stent removal with curative results was accomplished in 2 patients with tracheomalacia and 1 with post-intubation stenosis. In malignant cases, the median duration of stenting was 162 days (range, 1-1,279 days). Five patients had tumor progression with obstruction requiring repeated laser resection, dilatation, or additional stents. Two patients died due to airway obstruction despite bronchoscopic intervention. Twelve patients with malignant lesions died with the stent in place. At the end of the study, 3 patients with malignant disease remained alive; 2 were lost to follow-up. The HCPA-1 stent proved to be safe, with no severe complications during the study period, and effective in improving quality of life with relief of dyspnea.
Subject(s)
Airway Obstruction/therapy , Bronchial Diseases/therapy , Bronchoscopy/instrumentation , Silicones , Stents , Tracheal Stenosis/therapy , Adult , Aged , Airway Obstruction/diagnostic imaging , Airway Obstruction/etiology , Airway Obstruction/mortality , Brazil , Bronchial Diseases/diagnostic imaging , Bronchial Diseases/mortality , Bronchoscopy/adverse effects , Catheterization , Chi-Square Distribution , Device Removal , Dyspnea/etiology , Dyspnea/therapy , Female , Humans , Intubation, Intratracheal/adverse effects , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasms/complications , Palliative Care , Proportional Hazards Models , Prosthesis Design , Radiography , Time Factors , Tracheal Stenosis/diagnostic imaging , Tracheal Stenosis/etiology , Tracheal Stenosis/mortality , Tracheomalacia/complications , Tracheostomy/adverse effects , Treatment OutcomeABSTRACT
This article describes the development of a Nitinol tracheal stent (HCPA NiTi-stent) and its application in a feline animal model. Straight-annealed, bright-polished Nitinol wire (55.8%Ni-44.2%Ti) was weaved around a 40-mm-long metal fixture with 8-mm diameter. The prototypes were submitted to different times of shape-setting heat treatment (530 degrees C), which resulted in stents of different colors and caused some variation in length and diameter. The prototypes were then submitted to compression testing, and the most resistant pieces, requiring the greatest force to achieve a 25% reduction in diameter and presenting the least variation in length and diameter (dark blue, 9 min of heat treatment), were submitted to fatigue testing. After that, only dark blue stents were manufactured and implanted in felines. No migration, tracheal stenosis, or any other type of damage were observed after 40 weeks. The integrity of the tracheal wall in contact with the stent was confirmed by macro and microscopic analyses. The development and in vivo testing of the HCPA NiTi-stent were successful.
