[Endoscopic retrieval of metallic stents in patients with airway diseases]

To evaluate the indications, techniques, outcomes and complications of metallic stent removals in patients with airway disorders.

A retrospective analysis was performed in 43 patients with 47 tracheobronchial stents. The airway stent retrieval was performed under the guidance of rigid or flexible bronchoscopy between November 2005 and November 2009. There were 25 cases with 27 Z-type stents (25 covered metallic stents, CMS; 2 uncovered metallic stents, UCMS) and 18 cases with 20 Nitinol stents (4 CMS, 16 UCMS). Excessive stent-related granuloma formation or recurrent tumor in patients with UCMS group was similar to those with CMS (94.4% vs 89.7%). Fracture of stents in patients with UCMS group was higher than that in CMS group (83.3% vs 10.3%, P < 0.01).

Thirty-eight of 47 (80.9%) stents (Z-type stents 85.2%, Nitinol 75.0%) were successfully removed. Among them, 15 stents (39.5%) were retrieved by rigid bronchoscopy and 23 (60.5%) stents by flexible bronchoscopy (20 under local anesthesia and 3 under pain-free anesthesia). 87.0% (20/23) Z-type CMS was removed with a retrieval hook by a flexible bronchoscopy under local anesthesia with an average duration of pre-removal stenting of (3.5 +/- 0.6) months while 80% (12/15) Nitinol UCMS removed by a rigid bronchoscopy under general anesthesia with an average duration of pre-removal stenting of (10.7 +/- 3.7) months. A successful retrieval of intact stents was achieved in 84.0% (21/25) of CMS while 92.3% (12/13) of UCMS had a retrieval of rupture stent or piecemeal. In all cases, major post-removal complications included profuse hemorrhage (n = 4) and mucosal tear (n = 15). No mortality occurred during the procedure.

The indications for endoscopic retrieval of metallic stents include excessive or recurrent granuloma formation or tumor, recurrence of stenosis after stenting, stent fracture and conclusion of treatment, 3 - 4 months post-stenting in patients with benign stenoses. CMS can be effectively and safely removed with a retrieval hook by flexible bronchoscopy under local anesthesia without any major sequel. UCMS may be successfully retrieved by rigid bronchoscopy under general anesthesia.