Article Outline
CTSNet classification: 12, 15
We appreciate the interest that Drs Anile and Ventura have in the management of lung transplant recipients with distal focal bronchial stenosis (type 3 disease) and diffuse distal stenosis (type 4 disease). This is a complex group of patients to manage, and their airway issues can be challenging.1
As a high-volume center for bronchial stent placement (for causes other than transplantation), we have been uniformly disappointed with the use of expandable metallic stents. Metallic stents in the airway are expensive and associated with fracture, overgrowth of granulation tissue, and erosion through the tracheobronchial wall. Although the cost of a single metallic stent is low in comparison with the total expense of lung transplantation, cost precludes having a large inventory of these stents available. We currently have an inventory of more than 100 Silastic stents (Hood Laboratories, Pembroke, Mass, and Bryan Corporation, Woburn, Mass). This inventory allows us to find the right stent for almost any airway, to tailor a specific stent to an individual patient's needs, and to replace/upsize them as needed.
We have several practical tips for stenting of type 3 and 4 bronchial stenoses:
1.We have found that stenting of the subsegmental airways does not benefit the patient. Thus, we limit our stenting to the bronchial and segmental airways.
2.We calibrate the size of stent to be placed based on the size of the rigid bronchoscope that we are able to insert in the portion of bronchus affected. For example, if we are able to cannulate the affected bronchus with a 10-mm rigid bronchoscope, we would size the proximal portion of the stent to 10 to 12 mm.
3.For difficult and long stenoses, we often dilate the bronchus/segment and insert as large a stent as possible. In 2 to 3 months, we remove the stent and replace it with a larger diameter stent. This can be done sequentially to maximally dilate the affected area.
4.For distal left-sided problems, we routinely place the stent over the bifurcation of the upper and lower lobes and cut a small circular segment out of the stent using a 6-mm dermal punch (Acuderm, Fort Lauderdale, FL). This stent contouring maintains the integrity of the stent while allowing for ventilation of the upper lobe, which would otherwise be obstructed.
5.For distal right-sided problems, we use step-down stents of various configurations (Hood Silastic 2-Step Stents with Posts and Mesh: Hood Laboratories). A step-down stent is one in which the proximal diameter is larger than the distal diameter, with tapering of the stent diameter in between. Step-down stents allow coverage down to the level of the superior segment of the lower lobe and right middle lobe, while maintaining patency and coverage of the anastomosis and proximal mainstem bronchus. We usually cut a 6-mm dermal punch hole in the stent for the right upper lobe to allow ventilation to this lobe. The right upper lobe orifice is often variable in its position, so we have not found stents with premade orifices effective for use.
6.While inserting Silastic stents, we have found that it is important to place the hole for a lobar orifice corresponding to the print on the metallic applicator (Dumon-Harrell applicator: Bryan Corporation). This configuration allows for easy rotation of the stent (clockwise for right bronchial stents, counterclockwise for left bronchial stents) into the appropriate position as it is deployed. After stent deployment, we then often put a flexible bronchoscope through the rigid bronchoscope into the stent while using rigid forceps to manipulate the hole into its most optimal position.
Our experience has been that bronchoscopic surveillance and sequential “up-size” stenting for distal long-segment stenoses is an effective way to permanently increase luminal diameter over a long length of airway.
Back to Article Outline
Reference
- Thistlethwaite PA, Yung G, Kemp A, Osbourne S, Jamieson SW, Channick C, et al. Airway stenoses after lung transplantation: incidence, management, and outcome. J Thorac Cardiovasc Surg. 2008;136:1569–1575
