Ann Thorac Surg 1998;66:1925-1929
© 1998 The Society of Thoracic Surgeons
Original Articles
Stenting for airway obstruction in the carinal region
Takeshi Shiraishi, MDa,
Katsunobu Kawahara, MDa,
Takayuki Shirakusa, MDa,
Kazuo Inada, MDa,
Kan Okabayashi, MDa,
Akinori Iwasaki, MDa
a General Thoracic Surgery, Second Department of Surgery, Fukuoka University School of Medicine, Fukuoka, Japan
Accepted for publication June 9, 1998.
Address reprint requests to Dr Shiraishi, Second Department of Surgery, Fukuoka University School of Medicine, Nanakuma 7-45-1, Jonan-ku, Fukuoka 814-0180, Japan
 |
Abstract
|
|---|
Background. Recent progress on airway stents has provided sufficient airway patency for patients with airway obstruction; however, when the stenosis exists in the carinal zone, establishing an excellent airway condition is still troublesome because of the anatomic structure.
Methods. We treated 15 patients with severe tracheobronchial stenosis involving a carinal bifurcation region, using several types of stenting devices (long T-tube, T-Y tube, wire reinforced Y tracheostomal tube, Freitag Dynamic stent [Karl Storz, Tuttlingen, Germany], and covered metallic stent). All patients had advanced inoperable tumors (lung cancer, n = 6; esophageal cancer, n = 3; thyroid cancer, n = 3; mediastinal tumor, n = 3).
Results. All but 2 patients had immediate relief of respiratory symptoms. One patient died of respiratory failure caused by pulmonary lymphatic spread 3 days after Dynamic stent insertion. In 1 patient with severe left main bronchial stenosis due to lung cancer, effective palliation was not achieved by insertion of a covered metallic stent because of its insufficient expansion against the stenosis. Mean survival after successful stenting was 4.3 months (range, 1 to 15 months). There were no complications directly attributable to the stents.
Conclusions. As evidenced by the clinical effectiveness, airway stenting for inoperable tumor is valuable in such patients. Choosing a stent that will fully cover the lesion and allow sufficient tolerance against compression is important to successful stenting. Benefits such as ease of phonation and stent maintenance should also be considered.
|
Introduction
|
|---|
The main objective of treatment for malignant airway stenosis is to relieve the distress by establishing patency. Stenting is the most functional strategy for such patients when surgical treatment is not indicated. However, because of the anatomic structure, processes are extremely difficult to address when lesions involve carinal bifurcation. Recently, stents that are useful for such problem triangle zones have been made available. These new devices may provide satisfactory palliation for patients with inoperable malignant stenosis in the tracheocarinal zone.
|
Patients and methods
|
|---|
From July 1994 to June 1997, 15 patients with malignant airway obstruction in the lower tracheal or carinal zone were treated in our institute. All had advanced inoperable disease (lung cancer, n = 6; esophageal cancer with tracheobronchial invasion, n = 3; thyroid cancer, n = 3; mediastinal tumor, n = 3). Patients with upper airway obstruction that could be treated by tracheostomy with conventional tracheostomy tubes were excluded from the study.
Stents
When the stenosing lesion was located in the distal trachea not completely involving but close to the carinal triangle, a long T-tube was used. Each stent was specially designed for each patient to cover the stenotic lesion completely. A silicone T-Y tube (Fig 1) or a wire reinforced Y-shaped tracheostomy tube (WR-Y tube) was used when lesions involved carinal bifurcation. The T-Y tube and the long T-tube made of silicone rubber were commercially available by special order to fit each patient (Koken Co, Tokyo, Japan). Because both the long T and T-Y tubes are made fully of silicone rubber, the tolerance against severe stenosis is often insufficient to maintain airway patency. Thus, the WR-Y tube was designed in our institute [1]. The WR-Y tube consists of a pliable, curved silicone rubber cylinder and a bifurcated distal end to be inserted into the right and left main bronchi. A spiral stainless steel wire is implanted in the part of the distal trachea that will contain the tube for protection against either deformity or stenosis due to severe airway dehiscence. To facilitate phonational activity, a circular window measuring 1.5 cm in diameter is made on the dorsal side of the curved portion of the tube (Fig 2).
View larger version (19K):
[in this window]
[in a new window]
|
Fig 1. Silicone rubber T-Y tube. Bronchoscope is inserted from the upper orifice of the tube into the left bronchial cylinder and is introduced into the tracheostomy. The right bronchial tube is pushed forward during tube advancement into the trachea.
|
|
View larger version (138K):
[in this window]
[in a new window]
|
Fig 2. Wire-reinforced Y-shaped tracheostomy tube. (A) Frontal and posterior view, showing the hole made at the dorsal side for phonation. (B) Part of the lower trachea and bifurcation.
|
|
The Freitag Dynamic airway stent (Karl Storz, Tuttlingen, Germany), which was designed recently for carinal or distal tracheal stenosis, was used for patients with carinal stenosis. It is a bifurcated silicone stent designed according to anatomic studies of the central airway. The tracheal part is horseshoe shaped with steel struts to provide stability against tumor compression. A flexible posterior membrane made of silicone allows for high flow velocities by bulging inward during cough or forced expiration and thus improves mucus clearance by gas–liquid interaction (Fig 3) [2]. Because the Freitag Dynamic stent does not fully cover the subglottic area, a long T, T-Y, or W R-Y tube is considered for use when the lesion extends to the subglottic area.
In cases of main bronchial stenosis that did not completely involve the carina but did extend to the orifice of main bronchus, we used an artificial skin-covered, metallic, self-expandable stent (12 mm in diameter and 30 mm in length; William Cook Co, Bjaeverskov, Denmark). Metallic stents are not effective against proliferating granulation tissue, neoplasms, or increased secretion. To overcome such problems, stents were covered with a biosynthetic skin substitute (Biobrane; Dow B. Hickam Inc, Sugar Land, TX), which provides enough friction for adequate stability as well as protection against proliferating neoplasm or secretion (Fig 4).
Procedure for stent insertion
Five of the 15 patients underwent laser ablation for intraluminal neoplasm before stenting to obtain enough space for stent insertion.
The long T, T-Y and WR-Y tubes were inserted easily through the tracheostomy under local anesthesia with the aid of a fiberoptic bronchoscope. In the T-Y or WR-Y tube insertion, the bronchoscope is inserted through the upper orifice of the tube into the left bronchial cylinder and is introduced into the tracheostomy. The right bronchial tube is pushed forward during tube advancement into the trachea. When the tube reaches the level of the carinal bifurcation, the right main bronchial tube slides up into the right main bronchus spontaneously. Then, in the long T or T-Y tube, the upper end of the tracheal cylinder is placed into the trachea.
The Freitag Dynamic stent was inserted under deep sedation using a specially designed forceps. Using this dedicated instrument, the stent can be grasped from inside, and with its bronchial limbs folded together, the prosthesis is inserted orally like an endobronchial tube. However, the first 2 patients with esophageal carcinoma presented severe vocal cord edema during the procedure. Thus, emergency tracheostomies were performed, and the tube was inserted through the tracheostoma, with the proximal end of the tube remaining exposed through the stoma (Fig 5). Two or 3 days after insertion, when the vocal cord edema was ameliorated, the proximal end was placed into the trachea.
View larger version (17K):
[in this window]
[in a new window]
|
Fig 5. The Dynamic stent can be inserted through the tracheostomy in case of airway obstruction in the upper trachea or larynx.
|
|
Metallic stents covered with biosynthetic skin substitute are inserted under fluoroscopic guidance. A delivery catheter is passed over the guidewire, which is inserted beyond the stricture by bronchofiberscope. The stent, loaded in compressed form in the delivery catheter, is advanced through the catheter lumen. We experienced no difficulties in passing the covered stent through the delivery catheter.
|
Results
|
|---|
Patient characteristics and outcomes are summarized in Tables 1 and 2. All but 2 patients had immediate relief of respiratory symptoms. Mean survival after successful stenting was 4.3 months (range, 1 to 15 months). One patient died 3 days after insertion of the Dynamic stent of respiratory failure caused by pulmonary lymphatic spread. The other patient with left main bronchial stenosis caused by lung cancer was given a covered metallic stent; however, the stent did not expand sufficiently against the compression of the surrounding neoplastic tissue.
Long T, T-Y, or WR-Y tube
All 5 patients who were given the long T, T-Y, or WR-Y tube had immediate relief of their respiratory symptoms. One patient with thyroid cancer (patient 4) was first given the Dynamic stent. However, because of respiratory distress due to laryngeal edema during the procedure, it was necessary to perform emergency tracheostomy and then insert a T-Y tube through the tracheostoma.
Of these 5 patients, 4 were discharged from the hospital and remained at home with excellent respiratory condition. They all mastered the self-suctioning technique before returning home. No complications were noted during stent insertion.
Dynamic stent
The Dynamic stent was used for 6 patients with inoperable esophageal carcinoma with tracheal invasion (n = 3) or pulmonary or mediastinal malignancy (n = 3). Two patients with esophageal carcinoma presented tracheo- or bronchoesophageal fistula. The stent was effective for preventing secretion from the tracheoesophageal fistula as well as maintaining a sufficient airway.
Covered metallic stent
The covered metallic stent was used for 4 patients with lung cancer. Two patients were given the stent for left main bronchial stenosis. One patient (patient 15) was given the stent for stenosis at main bronchus to intermediate bronchus caused by peribronchial lymph node recurrence after right upper lobectomy for lung cancer. These 3 patients were given a single stent 12 mm in diameter and 30 mm in length. One patient (patient 13) presented obstruction at the left main bronchus with complete obstruction of right main bronchus due to peribronchial lymph node metastasis from lung cancer. Stenosis was extended into the lower trachea, therefore, one bronchial stent (12 mm by 30 mm) and two tracheal stents (15 mm by 30 mm) were inserted. There was no space for stent insertion into the right main bronchus. In 1 of 4 patients (patient 14), sufficient palliation could not be achieved because of severe malignant stenosis.
|
Comment
|
|---|
The main objective of treatment for nonresectable airway stenosis is the relief of respiratory distress. Intraluminal neoplasm or granulation can be managed by endoscopic resection with biopsy forceps [3] or laser ablation [4]. Balloon dilation is sometimes useful. Among the different techniques used to restore patency in obstructive lesions, stents are the mainstay. However, with carinal bifurcation including the lower trachea it is most difficult to maintain a sufficient airway because of the anatomic structure.
When the stenosis fully involves the carinal triangle, a Y-shaped device must be used for maintaining the airway sufficiently. The bifurcated silicone rubber stent was first designed by Westaby and Jackson [5]. Their stent, which is the same in design as our T-Y stent, consisted of a main tracheal stent with a bifurcated main bronchial tube connecting to a T-cylinder through the anterior tracheal wall. However, based on our experience, extensive tracheobronchial stenosis, which requires this type of stent, usually causes marked stricture caused by the neoplastic tissue. Because the stent is made of silicone rubber, its tolerance against stenosis is usually unsatisfactory. Therefore, we designed the wire-reinforced Y-shaped tracheostomal tube for severe airway obstruction with carinal or distal tracheal stenosis. We suggest that commercially available long T or T-Y silicone rubber tubes be used only for mild obstruction.
The recently designed Dynamic stent is another excellent choice for stenting [2]. This device can be introduced like a rigid bronchoscope using a especially designed instrument. However, as shown in Table 3, two of our patients (patients 7 and 8) experienced respiratory failure due to laryngeal edema during insertion. The stents were extubated and tracheostomies were performed immediately. Here, we were able to achieve a technical modification for safe insertion (Fig 4). This seems to be a satisfactory recourse for patients with severe respiratory conditions.
In comparing the Dynamic stent with the three types of tracheostomal tube (long T, T-Y, WR-Y tubes), one of the advantages of the tracheostomal tubes is the possibility for airway patency when the extended stenosis exists in the upper trachea or larynx. These tracheostomal tubes can be used for such patients because they have a vertical arm protruding through the anterior tracheal wall. This seems to be an advantage over the Dynamic stent, which cannot cover obstructions up to the highest part of the trachea or vocal cords. In addition, with these stents inserted through the tracheostoma, suctioning or inspection by bronchoscope can be performed easily. This easy airway maintenance makes it possible for patients to live at home and have an excellent quality of life, even patients with a large volume of secretion. Such advantages seem to be especially important for terminally ill patients.
The expandable metallic stent is the other choice when a lesion exists in the main bronchus or more distally. Y-shaped silicone devices may be used for such main bronchial stenoses. However, the part of the cylinder that resides in the main bronchus may not be strong enough against the stenosis. Thus, we use a metallic stent if the air space maintained at the carinal triangle is sufficient. The expandable metal stent is inserted very easily using a flexible bronchoscope. The placement of this type of stent requires considerably less experience than placement of the rigid-type stent, and the risk of injury during insertion is minimal. However, metallic stents are not effective against proliferating granulation tissue, neoplasms, or increased secretion. Silicone sheets or artificial vascular grafts have been used for wrapping. We used a skin substitute that provides enough protection against proliferating neoplasm or granulation. This covering may also protect against migration of the wire structure into the bronchial wall. However, on the basis of our experience, the tolerance of metallic stents against neoplastic stricture is still in question in comparison with wire-reinforced silicone devices.
In summary, stenting is the best strategy for nonresectable airway obstruction. Stents, such as the Dumon tube [6] and other newly designed metallic devices [7], are being used. The proper stent should be chosen for each patient to improve quality of life.
|
References
|
|---|
-
Shiraishi T., Okabayashi K., Kuwahara M., et al. Y-shaped tracheo-bronchial stent for carinal and distal tracheal stenosis. Surg Today 1998;28:328-331.[Medline]
-
Freitag L., Tekolf E., Stamatis G., Greschuchna D. Clinical evaluation of a new bifurcated dynamic airway stent: a 5-year experience with 135 patients. Thorac Cardiovasc Surg 1997;45:6-12.[Medline]
-
Mathisen D.J., Grillo H.C. Endoscopic relief of malignant airway obstruction. Ann Thorac Surg 1989;48:469-475.[Abstract/Free Full Text]
-
Goldberg M. Endoscopic laser treatment for bronchogenic carcinoma. Surg Clin North Am 1988;68:635-644.[Medline]
-
Westaby S., Jackson J.W. A bifurcated silicone rubber stent for relief of tracheobronchial obstruction. J Thorac Cardiovasc Surg 1982;83:414-417.[Abstract]
-
Dumon J.F. A dedicated tracheo-bronchial stent. Chest 1990;97:328-332.[Medline]
-
Becker H.D. Stenting of the central airways. J Bronchology 1995;2:98-106.
This article has been cited by other articles:
|
|
|
|
 
S. D. Murgu and H. G. Colt
Silicone Y stent placement at secondary left carina for malignant central airway obstruction
J. Thorac. Cardiovasc. Surg.,
February 1, 2010;
139(2):
494 - 495.
[Full Text]
[PDF]
|
|
|
|
|
|
|
H.-S. Nam, S. W. Um, W.-J. Koh, G. Y. Suh, M. P. Chung, O. J. Kwon, J. Kim, and H. Kim
Clinical Application of the Natural Y Stent in the Management of Benign Carinal Stenosis
Ann. Thorac. Surg.,
August 1, 2009;
88(2):
432 - 439.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. Chen and S. Jiang
A Novel Anatomy-Conforming Metallic Stent for Tracheobronchial Stenosis
Ann. Thorac. Surg.,
June 1, 2008;
85(6):
2100 - 2103.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. P.L. Lo, T. B. Soo, A. A.L. Hsu, and P. C.T. Eng
Treatment of severe carinal stenosis with overlapping metallic endoprosthesis
Ann. Thorac. Surg.,
April 1, 2001;
71(4):
1335 - 1336.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
