Airway Stents for Excessive Dynamic Airway Collapse

American Association of Broncology and Interventional Pulmonology, Curetbm.org Fundation, Hood Laboratories, Boston Medical products inc

Airway stents are used as standard of care to identify which patients with excessive dynamic airway collapse will benefit from a definitive surgical treatment. However, the specific way in which these stents are effective has not been tested. The purpose of this research study is to determine the effectiveness of airway stents when used in the airways of patients with severe symptomatic excessive dynamic airway collapse compared to patients with severe symptomatic excessive dynamic airway collapse that do not receive airway stent.

Study Design This randomized controlled trial will be conducted at Beth Israel Deaconess Medical Center (BIDMC) in accordance with Good Clinical Practice Standards and under IRB supervision. We plan to enroll total of 48 patients with EDAC randomized by a computer generated system to either intervention group (airway stent) or medical management group. Description of the study Previous to appointment all patients will have Airway CT scan, 6 minute walk test and pulmonary function test as per protocol and standard of care. Enrollment Patients with severe EDAC who remain symptomatic despite optimal medical management will be informed about the trial and if interested will be recruited for the study. Operative Technique Patients in the treatment group (stent) will undergo bronchoscopy under light sedation and rigid bronchoscopy under general anesthesia. The treatment group will undergo a bronchial wash and placement of an airway stent.Patients assigned to the medical management group will not undergo bronchoscopy. Stents Based on the patient's airway anatomy an uncovered self-expanding metallic stent (Ultraflex™ Single-Use Tracheobronchial Stent System) or a silicone Y-stent(Endoxane, Novatech S.A., Aubagne-France or Channick Hood Laboratories, Pembroke, MA, 02359) will be used in the study. During Stent Trial After bronchoscopy, patients in the treatment group will receive a standardized medication regimen to include mucolytics, cough suppressors and expectorants in order to decrease the risk of potential complications following the procedure. Follow-up All participants will be scheduled for a follow-up visit in the following 14 days either after rigid bronchoscopy (treatment group) or after first visit (medical management group) with 6MWTs and PFTs. In this visit all patients will be asked to complete the SGRQ, CQLQ and mMRC questionnaires by the research team. All this data will be recorded in an encrypted database. Afterwards, the patients in the medical management arm will be offered a stent trial as part of standard of care. Stent removal The patients from the treatment arm will be scheduled for a rigid bronchoscopy, stent removal and bronchial lavage under anesthesia in the operating room.

The patients assigned to the medical management group will be placed on a scheduled institution protocol using mucolytic and expectorant therapy (nebulizer treatments using mucolytic (N-acetylcysteine) for 15 minutes BID, Guafenesin (Mucinex®) 1200 mg BID, codeine as needed and Flutter valve BID.

The patients assigned to treatment group will undergo flexible bronchoscopy with dynamic maneuvers, rigid bronchoscope , tracheobronchial wash and airway stent placement

The bronchoscope will be introduced into the proximal trachea at the level of the cricoid. At that point, patients will be instructed to take a deep breath, hold it and then blow it out (forced expiratory maneuver). Maneuvers will be done at the following six sites: proximal trachea at the level of the cricoid; mid-trachea 5 cm proximal to the carina; distal trachea 2 cm proximal to the carina; right main stem bronchus at the right tracheobronchial angle; bronchus intermedius and left main bronchus at the left tracheobronchial angle

Under general anesthesia, a rigid bronchoscope (Bryan-Dumon Series II; Bryan Corporation; Woburn, MA) will be introduced, and respiration will be maintained through jet ventilation.

Silicone Y stent or uncovered self-expanding metallic stent will be placed in the standard fashion and good fit will be confirmed visually.

Inclusion Criteria: Patient with sever symptomatic EDAC (collapse >90% of the airway during exhalation at dynamic CT scan) Age > 18 years Exclusion Criteria: Patients who have not been well managed from their respiratory comorbidities (asthma, COPD, obstructed sleep apnea, GERD, relapsing polychondritis) Current respiratory infection Resting bradycardia (<50 beats/min), frequent multifocal PVCs, complex ventricular arrhythmia, sustained SVT Dysrhythmia that might pose a risk during exercise or training Any disease or condition that interferes with completion of initial or follow-up assessments

Leong P, Bardin PG, Lau KK. What's in a name? Expiratory tracheal narrowing in adults explained. Clin Radiol. 2013 Dec;68(12):1268-75. doi: 10.1016/j.crad.2013.06.017. Epub 2013 Aug 13.

Murgu S, Colt H. Tracheobronchomalacia and excessive dynamic airway collapse. Clin Chest Med. 2013 Sep;34(3):527-55. doi: 10.1016/j.ccm.2013.05.003. Epub 2013 Jun 27.

Ridge CA, O'donnell CR, Lee EY, Majid A, Boiselle PM. Tracheobronchomalacia: current concepts and controversies. J Thorac Imaging. 2011 Nov;26(4):278-89. doi: 10.1097/RTI.0b013e3182203342.

Boiselle PM, O'Donnell CR, Bankier AA, Ernst A, Millet ME, Potemkin A, Loring SH. Tracheal collapsibility in healthy volunteers during forced expiration: assessment with multidetector CT. Radiology. 2009 Jul;252(1):255-62. doi: 10.1148/radiol.2521081958. Epub 2009 May 6.

Carden KA, Boiselle PM, Waltz DA, Ernst A. Tracheomalacia and tracheobronchomalacia in children and adults: an in-depth review. Chest. 2005 Mar;127(3):984-1005. doi: 10.1378/chest.127.3.984.

Jokinen K, Palva T, Nuutinen J. Chronic bronchitis. A bronchologic evaluation. ORL J Otorhinolaryngol Relat Spec. 1976;38(3):178-86. doi: 10.1159/000275273.

Palombini BC, Villanova CA, Araujo E, Gastal OL, Alt DC, Stolz DP, Palombini CO. A pathogenic triad in chronic cough: asthma, postnasal drip syndrome, and gastroesophageal reflux disease. Chest. 1999 Aug;116(2):279-84. doi: 10.1378/chest.116.2.279.

Ikeda S, Hanawa T, Konishi T, Adachi M, Sawai S, Chiba W, Kosaba S, Hatakenaka R, Matsubara Y, Funatsu T. [Diagnosis, incidence, clinicopathology and surgical treatment of acquired tracheobronchomalacia]. Nihon Kyobu Shikkan Gakkai Zasshi. 1992 Jun;30(6):1028-35. Japanese.

Majid A, Gaurav K, Sanchez JM, Berger RL, Folch E, Fernandez-Bussy S, Ernst A, Gangadharan SP. Evaluation of tracheobronchomalacia by dynamic flexible bronchoscopy. A pilot study. Ann Am Thorac Soc. 2014 Jul;11(6):951-5. doi: 10.1513/AnnalsATS.201312-435BC.

Lee KS, Sun MRM, Ernst A, Feller-Kopman D, Majid A, Boiselle PM. Comparison of Dynamic Expiratory CT With Bronchoscopy for Diagnosing Airway Malacia: A Pilot Evaluation. Chest. 2007 Mar;131(3):758-764. doi: 10.1378/chest.06-2164.

Ernst A, Majid A, Feller-Kopman D, Guerrero J, Boiselle P, Loring SH, O'Donnell C, Decamp M, Herth FJ, Gangadharan S, Ashiku S. Airway stabilization with silicone stents for treating adult tracheobronchomalacia: a prospective observational study. Chest. 2007 Aug;132(2):609-16. doi: 10.1378/chest.06-2708.

Litmanovich D, O'Donnell CR, Bankier AA, Ernst A, Millett ME, Loring SH, Boiselle PM. Bronchial collapsibility at forced expiration in healthy volunteers: assessment with multidetector CT. Radiology. 2010 Nov;257(2):560-7. doi: 10.1148/radiol.10100219. Epub 2010 Sep 9.

Majid A, Sosa AF, Ernst A, Feller-Kopman D, Folch E, Singh AK, Gangadharan S. Pulmonary function and flow-volume loop patterns in patients with tracheobronchomalacia. Respir Care. 2013 Sep;58(9):1521-6. doi: 10.4187/respcare.02277. Epub 2013 Mar 12.

Tamura Y, Sakatani K, Yamakoshi N, Terada H, Honda H, Komori C, Kuhara H, Morishita N, Shishido K, Matsuoka H, Shishido N, Ishihara H. [A case of severe COPD associated with tracheo-bronchial stenosis, treated with non-invasive positive pressure ventilation]. Nihon Kokyuki Gakkai Zasshi. 2008 Nov;46(11):915-20. Japanese.

Ferguson GT, Benoist J. Nasal continuous positive airway pressure in the treatment of tracheobronchomalacia. Am Rev Respir Dis. 1993 Feb;147(2):457-61. doi: 10.1164/ajrccm/147.2.457.

Adliff M, Ngato D, Keshavjee S, Brenaman S, Granton JT. Treatment of diffuse tracheomalacia secondary to relapsing polychondritis with continuous positive airway pressure. Chest. 1997 Dec;112(6):1701-4. doi: 10.1378/chest.112.6.1701.

Wright CD. Tracheomalacia. Chest Surg Clin N Am. 2003 May;13(2):349-57, viii. doi: 10.1016/s1052-3359(03)00036-x.

Gangadharan SP, Bakhos CT, Majid A, Kent MS, Michaud G, Ernst A, Ashiku SK, DeCamp MM. Technical aspects and outcomes of tracheobronchoplasty for severe tracheobronchomalacia. Ann Thorac Surg. 2011 May;91(5):1574-80; discussion 1580-1. doi: 10.1016/j.athoracsur.2011.01.009. Epub 2011 Mar 5.

Majid A, Guerrero J, Gangadharan S, Feller-Kopman D, Boiselle P, DeCamp M, Ashiku S, Michaud G, Herth F, Ernst A. Tracheobronchoplasty for severe tracheobronchomalacia: a prospective outcome analysis. Chest. 2008 Oct;134(4):801-807. doi: 10.1378/chest.08-0728.

Ernst A, Odell DD, Michaud G, Majid A, Herth FFJ, Gangadharan SP. Central airway stabilization for tracheobronchomalacia improves quality of life in patients with COPD. Chest. 2011 Nov;140(5):1162-1168. doi: 10.1378/chest.10-3051. Epub 2011 Aug 25.

Murgu SD, Colt HG. Complications of silicone stent insertion in patients with expiratory central airway collapse. Ann Thorac Surg. 2007 Dec;84(6):1870-7. doi: 10.1016/j.athoracsur.2007.07.026.

Machuzak M, Santacruz JF, Gildea T, Murthy SC. Airway complications after lung transplantation. Thorac Surg Clin. 2015;25(1):55-75. doi: 10.1016/j.thorsurg.2014.09.008.

Chhajed PN, Malouf MA, Tamm M, Spratt P, Glanville AR. Interventional bronchoscopy for the management of airway complications following lung transplantation. Chest. 2001 Dec;120(6):1894-9. doi: 10.1378/chest.120.6.1894.

Zhang J, Hasegawa I, Feller-Kopman D, Boiselle PM. 2003 AUR Memorial Award. Dynamic expiratory volumetric CT imaging of the central airways: comparison of standard-dose and low-dose techniques. Acad Radiol. 2003 Jul;10(7):719-24. doi: 10.1016/s1076-6332(03)80117-4.

Odell DD, Majid A, Gangadharan SP, Ernst A. Adoption of a standardized protocol decreases serious complications of airway stenting in patients with tracheobronchomalacia. Chest. 2010; 138(suppl 4):A784

Jones PW, Quirk FH, Baveystock CM. The St George's Respiratory Questionnaire. Respir Med. 1991 Sep;85 Suppl B:25-31; discussion 33-7. doi: 10.1016/s0954-6111(06)80166-6.

Bestall JC, Paul EA, Garrod R, Garnham R, Jones PW, Wedzicha JA. Usefulness of the Medical Research Council (MRC) dyspnoea scale as a measure of disability in patients with chronic obstructive pulmonary disease. Thorax. 1999 Jul;54(7):581-6. doi: 10.1136/thx.54.7.581.

French CT, Irwin RS, Fletcher KE, Adams TM. Evaluation of a cough-specific quality-of-life questionnaire. Chest. 2002 Apr;121(4):1123-31. doi: 10.1378/chest.121.4.1123.

Jones PW. St. George's Respiratory Questionnaire: MCID. COPD. 2005 Mar;2(1):75-9. doi: 10.1081/copd-200050513.

Donohue JF. Minimal clinically important differences in COPD lung function. COPD. 2005 Mar;2(1):111-24. doi: 10.1081/copd-200053377.

Puhan MA, Chandra D, Mosenifar Z, Ries A, Make B, Hansel NN, Wise RA, Sciurba F; National Emphysema Treatment Trial (NETT) Research Group. The minimal important difference of exercise tests in severe COPD. Eur Respir J. 2011 Apr;37(4):784-90. doi: 10.1183/09031936.00063810. Epub 2010 Aug 6.

de Torres JP, Pinto-Plata V, Ingenito E, Bagley P, Gray A, Berger R, Celli B. Power of outcome measurements to detect clinically significant changes in pulmonary rehabilitation of patients with COPD. Chest. 2002 Apr;121(4):1092-8. doi: 10.1378/chest.121.4.1092.

Fletcher KE, French CT, Irwin RS, Corapi KM, Norman GR. A prospective global measure, the Punum Ladder, provides more valid assessments of quality of life than a retrospective transition measure. J Clin Epidemiol. 2010 Oct;63(10):1123-31. doi: 10.1016/j.jclinepi.2009.09.015. Epub 2010 Mar 19.

Nouraei SM, Franco RA, Dowdall JR, Nouraei SA, Mills H, Virk JS, Sandhu GS, Polkey M. Physiology-based minimum clinically important difference thresholds in adult laryngotracheal stenosis. Laryngoscope. 2014 Oct;124(10):2313-20. doi: 10.1002/lary.24641. Epub 2014 Apr 4.

Shlomi D, Peled N, Shitrit D, Bendayan D, Amital A, Kramer MR. Protective effect of immunosuppression on granulation tissue formation in metallic airway stents. Laryngoscope. 2008 Aug;118(8):1383-8. doi: 10.1097/MLG.0b013e318172d686.

Jones PW. Interpreting thresholds for a clinically significant change in health status in asthma and COPD. Eur Respir J. 2002 Mar;19(3):398-404. doi: 10.1183/09031936.02.00063702.