Clinical Evaluation Report

Author: Isidoro Ricardo

Publication survey summary and clinical history report.

This article summarizes the data given in several published clinical studies, in terms of side effects and critical data of the implantation process of Laringo – Tracheobronchial Prosthesis in humans.

Background and history-General

Laringo -Tracheobronchial Prosthesis are implantable devices that are indicated to maintain or support the diameter of an airway. They have been used to treat main airway obstructions in benign lesions and to relieve effects of neoplasic obstruction. In the last twenty years a great variety of such devices has been used worldwide. These prosthesis, like the “T” tube, first described by Montgomery in 1965, have given simple solutions to complex problems.

Design of canulas, tracheobronchial stents, and “T” tubes is simple. Mainly constructed in one piece without any rigid structure, they are safe and reliable. Airway reduction or complete obstruction severely compromises the patient, and after performing local treatment, the implantation of these devices has been highly effective to maintain airway permeability. Its use has been generalized. Its flexible silicone structure makes them easy to insert, and its removal is possible without complications.

Clinical study literature report

The following Studies/Articles were reviewed:

  1. Cavaliere S, Venuta F, Foccoli P, Tonielli C, La Face B. Endoscopic treatment of malignant airway obstructions in 2008 patients. Chest 1996; 110: 1536-42.
  2. Colt HC, and Dumon JF. Airway Obstruction in Cancer: The Pros and the Cons of Stents. Journal of Respiratory Disease 1991; 12, 8: 741-749.
  3. Dumon JF, Cavaliere S, Díaz Jimenez JP, et al. Seven-year experience with the Dumon prothesis. J Bronchol 1996; 3:6-10
  4. Bollinger CT. Airway stents. Semin Respir Crit Care Med 1997; 18:563.70.
  5. Gaissert HA, Grillo HC, Mathisen DJ, Wain JC. Temporary and Permanent Restoration of Airway Continuity with the Tracheal T-tube. Journal of Thoracic and Cardiovascular Surgery 1994; 107: 600-606.
  6. Korpela A, Aarnio P, Sariola H, Tormala P, Harjula A. Bioabsorbable self-reinforced plo-L-lactide, metallic and Silicone stents in the management of experimental tracheal stenosis. Chest 1999;115:490-5.
  7. Díaz-Jimenez JP, Farrero Muñoz E, Martinez Ballarin JI, Kovitz KL, Manresa Presas F. silicone Stents in the management of obstructive tracheobronchial lesions: 2-year experience. J Bronchol 1994;1:15-8.
  8. Silicones Stents in the management of obstructive tracheobronchial lesions: 2 –year experience. J Bronchol 1994; 109:626-9.
  9. Bollinger CT. Airway stents. Semin Respir Crit Care Med 1997; 18:563.70.
  10. Jantz, MA, Silvestri,GA. Controversy Silicone Stents versus Metal Stents for Management of Benign Tracheobronchial Disease. J Bronchol 2000; 7:177-183.
  11. Miyazawa T, Arita K. Airway stenting in Japan. Respirology 1998;3:229-34./li>
  12. Martínez – Ballarin JI, Díaz Gimenez JP, Castro MJ, Moya JA,. Silicone stents in the management of benign tracheobronchial stenosis: tolerance and early results in 63 patients. Chest 1996; 109:626-9
  13. Dumon, JF, Dumon, MC. Dumon-Novatech Y-Stents: A Four-Year Experience with 50 Tracheobronchial Tumors Involving the Carina. Journal of Bronchology 2000; 7:26-32.
  14. Section on Respiratory endoscopy of the German Society of Pulmonology (endorsed by Respiratory Endoscopy sections of Pulmonology Societies of Austria, Hungary, and Switzerland). Recommendations for Bronchoscopic Occlusions, Stenoses, and Mural Malignant Tumors. Journal of Bronchology 2000; 7:133-138.

Article Critical Evaluation Summary

From the articles above, the following data has been compiled:

  1. The efficacy is mainly based in its relatively simple use, good tolerance and capacity to maintain airway permeability
  2. Risk factors depend on previous local treatment, regardless of the device.
  3. Side effects described include secretions impact, migration, granuloma and colonization.

Success rate is related to the previous surgical procedures (airway reconstruction) and is not related to the performance of the device by itself.

Total mean of side effects:
Hipersecretion 4,0 %
Migration 9,3 %
Colonization n/a (Not Available)
Granuloma 6,7 %

Summary of results from articles

The use and placement of Laringo –Tracheobronchial Prosthesis has given proof of their utility to restore pulmonary ventilation and improve quality of life in non-surgical and post-surgical patients. They are widely used in benign stenosis with variable results. They can be left in place for long periods of time with acceptable compliance. Migration, secretions impact and granuloma are the most frequent complications.

Major Risk Factors

  • Migration
  • Secretions impact
  • Granuloma

Evaluation of Clinical Data

Attached to this report are 4 separate reports made by 9 physicians who use STENING devices.

A. Fiorino MD et al, who is a Bronchoscopist in Tornú Hospital, Buenos Aires.
B. Debais MD et al, who is a Pneumonologist in Tornú Hospital, Buenos Aires.
C. Isidoro MD, who is a Bronchoscopist in Tornú Hospital, Buenos Aires.
D. Botto MD et al. who are ENT Pediatricians in Garraham Hospital, Buenos Aires

Local Reports

A. Tratamiento endobronquial en la obstrucción de la vía aérea. 100 casos. Isidoro R. Debais . M., y Fiorino
B. Stent de silicona en obstrucciones traqueobronquiles, tres años experiencia.. Isidoro R. y Debais, M.Centro Endoscópico, Hospital Enrique Tornú
C. Stents de silicona. Test de comportamiento. Isidoro R.
D- Utilización de Stent en obstrucción de la vía aérea central en pediatría. Botto,H et al. Garrahan pediatric hospital. Buenos Aires-República Argentina.

Those reports were reviewed in comparison to data taken from the above articles, to evaluate the integrity of STENING Devices in comparison to state of the art devices in the market, as shown in reviewed clinical trials.

success rate is related to the previous surgical procedures (airway reconstruction) and is not related to the performance of the device by itself

Total mean of side effects:
Hipersecretion 8,3 %
Migration 5,0 %
Colonization 1,6 %
Granuloma 1,6 %

Evaluation of Clinical Data

Attached to this report are 4 separate reports made by 9 physicians who use STENING devices.

A. Fiorino MD et al, who is a Bronchoscopist in Tornú Hospital, Buenos Aires.
B. Debais MD et al, who is a Pneumonologist in Tornú Hospital, Buenos Aires.
C. Isidoro MD, who is a Bronchoscopist in Tornú Hospital, Buenos Aires.
D. Botto MD et al. who are ENT Pediatricians in Garraham Hospital, Buenos Aires

Time of permanence

The devices usually remain implanted during variable periods. From a few weeks to 24 months or more, depending on the survival of the patient or the control of his condition. Medical publications make little reference to the periods in which the devices remain implanted (14). This varies according to the therapeutic preferences of the working groups.

Although there is no consensus indicating the most appropriate length of stay, the usual in our environment is from a few days to 8 weeks for the laryngeal stent, and from 2 to 20 weeks for the cannulae and T tubes.
Tracheobronchial prostheses remain implanted for a longer time, depending on their initial indication, and can be from 6 to 18 months (D). There are reports of very long stays, which reach 4 and 5 years, with good tolerance and no alteration of the material of the device that motivates its extraction has been observed (1-13-C).

Usefull lifetime

In the reviewed literature, the devices were removed due to cure or remission of the treated conditions. In many cases the device remained implanted throughout the patient’s survival (1-13). The removal of the device for other reasons such as its deterioration, modification, decrease or loss of its mechanical qualities or rejection of its constituents were never reported.

In the case of implants that are introduced through the airway, their condition can be evaluated periodically with an endoscopic examination.

Although there is evidence of long stays of the implanted devices (1-13-D), and there are no references that suggest the loss of their functions in the airway, it is advisable to replace them after 18 months of implantation or when there are signs of colonization. All this will depend on the criteria of the acting physician and must be adjusted to the individual conditions of each case.

Conclusions

There is no relevant statistical difference between the Stening devices side effects rates with respect to other generic devices well established and widely used in the market.