Bronchial Stent Research Articles

The potential for bronchoscopic lung volume reduction using bronchial prostheses. A pilot study

The potential for bronchoscopic lung volume reduction using bronchial prostheses. A pilot study

The Potential for Bronchoscopic Lung Volume Reduction Using Bronchial Prostheses: A Pilot Study

Significant morbidity and mortality offset the benefits of lung volume reduction surgery (LVRS) for emphysema. By contributing to distal lung collapse, bronchoscopic placement of valved prostheses has the potential to noninvasively replicate the beneficial effects of LVRS. The purpose of this study was to investigate the safety and feasibility of placing valves in segmental airways of patients with emphysema. Case series. Tertiary hospital, severe airways disease clinic. Ten patients aged 51 to 69 years with apical emphysema and hyperinflation, otherwise suitable for standard LVRS. Mean preoperative FEV(1) was 0.72 L (19 to 46% predicted), and 6-min walk distance was 340 m (range, 245 to 425 m). Apical, bronchoscopic, segmental airway placement of one-way valves (silicone-based Nitinol bronchial stent; Emphasys Medical; Redwood City, CA) under general anesthesia. Placement was over a guidewire under bronchoscopic and fluoroscopic control. Four to 11 prostheses per patient took 52 to 137 min to obstruct upper-lobe segments bilaterally. Inpatient stay was 1 to 8 days. No major complications were seen in the 30-day study period. Minor complications included exacerbation of COPD (n = 3), asymptomatic localized pneumothorax (n = 1), and lower-lobe pneumonia (day 37; n = 1). Symptomatic improvement was noted in four patients. No major change in radiologic findings, lung function, or 6-min walk distance was evident at 1 month, although gas transfer improved from 7.47 +/- 2.0 to 8.26 +/- 2.6 mL/min/mm Hg (p = 0.04) and nuclear upper-lobe perfusion fell from 32 +/- 10 to 27 +/- 9% (mean +/- SD) [p = 0.02]. Bronchoscopic prostheses can be safely and reliably placed into the human lung. Further study is needed to explore patient characteristics that determine symptomatic efficacy in a larger patient cohort.

Benign Tracheobronchial Stenoses: Changes in Short-Term and Long-Term Pulmonary Function Testing After Expandable Metallic Stent Placement

To determine the short- and long-term improvement in airflow dynamics in patients undergoing tracheobronchial stent placement for benign airway stenoses. Twenty-two patients underwent 34 tracheal and/or bronchial stent placement procedures for benign airway stenoses and had the results of pulmonary function tests available. Stent placement indications included bronchomalacia after lung transplantation (n = 11), postintubation stenoses (n = 6), relapsing polychondritis (n = 2), and 1 each of tracheomalacia, tracheal compression, and histoplasmosis. Six patients underwent more than one stent placement procedure (range: 2-7 procedures). The mean forced expiratory volume in one second (FEV(1) ), forced expiratory flow rate in the midportion of the forced vital capacity curve (FEF(25-75) ), forced vital capacity, and peak flow (PF) rate obtained before stent placement were compared with those immediately after stent placement and with those measurements most remote from stent placement using the paired two-tailed test. All patients reported improved respiratory function immediately after stent placement. The mean FEV(1), FEF(25-75), and PF rate improved significantly (p < 0.001, p = 0.002, and p = 0.009, respectively) after stent placement. On long-term follow-up averaging 15 months after stent placement, these parameters declined despite patients' subjective sense of improvement. Segregating the population into transplant and nontransplant airway stenosis etiologies, however, FEF(25-75) and PF rate remained significantly improved (p = 0.045, p = 0.027, respectively), over the long term for the latter. FEV increased after subsequent stent placements for patients receiving multiple stents. Stent placement for benign tracheobronchial stenoses provides significant immediate improvement in airflow dynamics. Long-term improvement in airflow obstruction may be expected, and additional stent placements may further improve pulmonary function.

Lung and heart-lung transplantation in patients with end-stage cystic fibrosis: the stanford experience

Background. Bilateral lung (BLTx) and heart-lung transplantation have gained wide acceptance as treatment of end-stage lung disease from cystic fibrosis. We reviewed our 13-year experience with thoracic transplantation for cystic fibrosis with an operative approach that favors use of cardiopulmonary bypass for BLTx. Methods. Sixty-four patients with cystic fibrosis underwent heart-lung transplantation (n = 22, 34.4%) or BLTx (n = 42, 65.6%) between 1988 and 2000. Mean age and weight at transplantation were 29 ± 8 years and 51 ± 11 kg, respectively. Mean follow-up for survivors was 4.4 ± 3.6 years. Immunosuppression regimen included cyclosporine, tapered corticosteroids, azathioprine, and induction therapy with OKT3 (murine monoclonal antibodies) or rabbit antithymocyte globulin. Cardiopulmonary bypass was used in all but 5 patients (7.8%). However, in 8 (19%) of the 42 patients having BLTx, only the grafting of the second lung was performed with cardiopulmonary bypass. Results. The operative mortality rate was 1.6%. The actuarial survival rates at 1 year, 3 years, 5 years and 10 years were 93.2%, 77.7%, 61.8%, and 48.1%, respectively, with no significant difference between BLTx and heart-lung transplantation. The major hospital complications were pneumonia (n = 11, 17.2%) and bleeding (n = 8, 12.5%). Clinically significant reperfusion injury was observed in 6 patients, 3 of whom required reintubation. Freedom from acute lung rejection beyond 1 year was 47.7%. One patient underwent late retransplantation, and 4 required bronchial stenting. Obliterative bronchiolitis accounted for eight (50.0%) of 16 late deaths. Conclusions. Though postoperative bleeding and pneumonia are still of concern, satisfactory early and intermediate-term results can be expected in patients undergoing BLTx or heart-lung transplantation for cystic fibrosis. Cardiopulmonary bypass can be used for BLTx with no adverse impact on intermediate and long-term outcomes.

Experience with ultraflex expandable metallic stents in the management of endobronchial pathology

Background. Experience with Ultraflex expandable metallic stents (Micro-invasive, Boston Scientific, Watertown, MA) in the management of endobronchial pathologies leading to airway compromise is reported. Methods. Between January 1999 and August 2000, twenty-eight expandable metallic stents were inserted into 25 patients (7 men and 18 women; median age, 65 years) who presented with respiratory distress. Each patient had comorbid medical conditions or end-stage malignancy that precluded formal surgical repair. Seventeen patients had intrinsic airway obstruction, 5 had extrinsic compression, 2 had a tracheal tear, and 1 had a tracheoesophageal fistula. Stents were inserted through a bronchoscope under direct vision. Eighteen patients received tracheal stents alone (1 of these patients received two tracheal stents), and 5 patients received bronchial stents only. Two patients received a tracheal and a bronchial stent. Twenty-one stents were covered and seven were uncovered. Results. All patients had successful stents with restoration of airway patency and closure of tracheal defects. One patient developed a respiratory infection early after the operation. Follow-up bronchoscopy confirmed satisfactory stent position in each patient. Late complications included sputum retention, halitosis, and granulation tissue formation. Conclusions. Ultraflex expandable metallic stents should be considered in the management of airway compromise in selected patients for whom formal surgical repair is inappropriate or contraindicated.

Bronchoscopic lung volume reduction (BLVR) using bronchial prostheses: a pilot safety and efficacy study

Lung volume reduction surgery(LVRS) can provide symptomatic improvement in patients with advanced emphysema. Both the open and video-assisted approaches to LVRS are associated with significant morbidity and mortality. Selective bronchoscopic placement of prostheses into segmental bronchi has the potential to achieve LVRS by promoting absorption atelectasis without an incision or intercostal drainage. Aim: this phase 1 study reports the safety and efficacy of BLVR. Methods: following successful sheep experiments, patients with apical emphysema and hyperinflation (otherwise acceptable for standard approach LVR) had apical bronchoscopic segmental airway placement of one-way valves under general anesthesia. The 4 or 6mm valves were silicone based and mounted in a Nitinol bronchial stent (Emphasys Medical Inc, CA, USA). Placement was over a guidewire under bronchoscopic and fluoroscopic control. Results: 5 patients(2M,3F, age 57-69yrs)underwent BLVR. Mean preoperative FEV1 was 0.72L(0.38-1.02L, 23-34% predicted)with a 6minute walk of 354m(315-402m).6-11 prostheses per patient took 90-135 minutes to obstruct most or all upper lobe segments bilaterally. Inpatient stay was 2-8 days. Relatively minor complications seen include minor exacerabtion of COPD(n 3), hemoptysis, pneumothorax(managed with aspiration only) and lower lobe pneumonia(n 1 for each). Symptomatic improvement is noted in 3 of 5 and the other 2 are currently stable. At 1 month lung function is unchanged in 4 patients and imaging shows collapse in only 1 patient. Conclusion: BLVR is a potentially useful novel therapy for emphysema. This pilot study shows that BLVR protheses can be safely placed into the human lung. The absence of xray lung reduction or spirometric improvement likely indicates significant collateral ventilation is occurring, possibly from previously undescribed interlobar collaterals. Alternatively, valve leakage remains possible. Extended followup studies, with active attempts to collapse the obstructed segments are pending.

The use of a Dumon stent for the treatment of a bronchopleural fistula

We report the successful management of a bronchopleural fistula with bronchial stent placement combined with irrigation of the empyema cavity. A bronchopleural fistula occurred in a 67-year-old man after a right upper lobectomy for lung cancer. Resuturing of the bronchial stump plus omental wrapping and subsequent closure of the open stump with a pedicled flap of intercostal muscle were not effective. Consequently, we placed a Dumon stent in the right main bronchus to close the stump.

Heart-lung versus double-lung transplantation for suppurative lung disease

Objective: The purpose of this study was to compare outcomes after heart-lung or double-lung transplantation in patients undergoing transplantation because of end-stage suppurative lung disease. Methods: We reviewed our experience in patients with cystic fibrosis or bronchiectasis who had heart-lung or double-lung transplantation between January 1988 and September 1997. Twenty-three patients (14 male, 21 cystic fibrosis) had heart-lung transplantation and 24 patients (8 male, 19 cystic fibrosis) had double-lung transplantation. There were no statistically significant differences between the groups in age, weight, preoperative creatinine level, cytomegalovirus status, maintenance immunosuppression, or donor demographics. Patients received induction therapy with monoclonal (OKT3) or polyclonal (rabbit anti-thymocyte globulin) antibody. Results: Sixteen of 24 patients had double-lung transplantation after 1994 whereas 13 of 22 patients had heart-lung transplantation before 1991, allowing longer follow-up for the heart-lung group. Mean waiting times for transplantation were 270 ± 245 days (heart-lung) and 361 ± 229 days (double-lung; P = .20). The 1-, 3-, and 5-year actuarial survival figures were respectively 86%, 82%, and 65% (heart-lung) and 96%, 75%, and unavailable (double-lung; P = no significant difference). The 1-, 3-, and 5-year rates of freedom from obliterative bronchiolitis were respectively 77%, 61%, and 45% (heart-lung) and 86%, 78%, and unavailable (double-lung; P = no significant difference). Linearized overall infection rates (events/100 patient-days) were 2.05 ± 0.33 (heart-lung) and 2.34 ± 0.34 (double-lung; P = NS) at 3 months. Thirty-day survival was 100% (heart-lung) and 96% (double-lung). There were 7 late deaths among heart-lung recipients (3 obliterative bronchiolitis, 2 infection, 0 graft coronary artery disease, 2 other) whereas 2 late deaths related to obliterative bronchiolitis occurred in double-lung recipients. Graft coronary artery disease (all stenoses < 50%) affected 15% of heart-lung survivors, whereas 3 double-lung recipients (12.5%) required either bronchial dilatation or stenting. Conclusion: Heart-lung and double-lung transplantation provide similar palliation for patients with end-stage suppurative lung disease. Therefore double-lung transplantation should be the preferred operation for most patients with end-stage suppurative lung disease. (J Thorac Cardiovasc Surg 2000;119:466-76)

Balloon Dilation and Endobronchial Stent Placement for Bronchial Strictures after Lung Transplantation

To evaluate the effect of balloon dilation and endobronchial stent placement for bronchial fibrous stenoses and bronchomalacia after lung transplantation. Bronchial dilation and/or stent placement was performed on 25 lung transplant recipients. Indications included severe dyspnea with postobstructive pneumonia (n = 24) and respiratory failure (n = 1). All patients underwent pulmonary function testing (PFT) before and after bronchial dilation, the results of which were evaluated for changes. A total of 63 procedures were performed between February 1996 and December 1998. Thirty-five lesions were treated (18 were due to bronchomalacia, 17 were due to fibrosis). Areas treated included the left mainstem bronchus (n = 11), bronchus intermedius (n = 10), right mainstem bronchus (n = 7), left upper lobe bronchus (n = 4), right lower lobe bronchus (n = 2), and right middle lobe bronchus (n = 1). Bronchoscopic and/or bronchographic follow-up ranged from 1 to 34 months (mean, 15 months). Six-month primary patency of stents placed for bronchomalacia was 71% (10 of 14), with three of the four occlusions caused by mechanical failure of Palmaz stents in the mainstem bronchi. Six-month primary patency for treatment of fibrous strictures was 29%. Secondary patency at 1 year was 100% for both bronchomalacia and fibrous strictures. After treatment, there was a significant improvement in mean PFT results (P = .01-.0001). There was one acute complication, obstruction of the left lower lobe bronchus by a Wallstent treated by dilating a hole in the side of the stent. Balloon dilation and stent placement are safe and effective for bronchial strictures and bronchomalacia after lung transplantation, resulting in significant improvement in PFT results. However, there is almost universal restenosis in patients treated for fibrous strictures necessitating reintervention for prolonged patency.

Tracheobronchial sleeve resection with the use of a continuous anastomosis: Results of one hundred consecutive cases

Objective: We have used a continuous suture technique for all tracheal and bronchial anastomoses with satisfactory results in our institution. The objective of this article is to review our experience with sleeve resections using this technique and report the associated morbidity and mortality in 100 consecutive cases. Methods: Our experience with sleeve resection using a continuous suture (3-0 polypropylene) technique was reviewed in 100 consecutive cases. The median age of the patients was 53.3 years with a range of 21 to 81 years. There were 54 male patients and 46 female patients. Resection was undertaken for malignant disease in 81 patients, acquired stricture in 14 patients, benign tumor in 4 patients, and trauma in 1 patient. Among 28 patients in whom lung parenchyma was not resected, 16 patients had tracheal resection and 12 had bronchial sleeve resection. Sleeve pneumonectomy was undertaken in 2, sleeve lobectomy in 66, and sleeve segmentectomy in 4. Results: There were 12 postoperative complications (12%) and 2 postoperative deaths resulting from bronchoatrial fistula and pneumonia (2%). Stricture as a late complication occurred in 5 patients, 2 of whom required a bronchial stent. Other late complications were bougienage, reanastomosis, and completion pneumonectomy (1 each). Conclusion: Our experience suggests that the results of continuous suture technique are comparable with those from reported series using interrupted suture technique for tracheal and bronchial anastomosis. (J Thorac Cardiovasc Surg 1999;117:1112-7)

Acute traumatic rupture of the thoracic aorta: Delayed treatment with endoluminal covered stent. A report of two cases

Acute traumatic rupture of the thoracic aorta: Delayed treatment with endoluminal covered stent. A report of two cases

Bioabsorbable Bronchial Stent in an Animal Model

The purpose of this study was to examine the biocombatibility of and possible adverse tissue reactions in air-ways to a bioabsorbable bronchial stent made of self-reinforced poly-l-lactide in an animal model. Both silicone and metallic internal stents are used to treat bronchial stenosis. Absorbable stents may offer some benefits as compared with other available stents. Tissue reactivity has been minimal when absorbable materials were used in other organs, and extraction of the stent is unnecessary. Bioabsorbable 15 mm long spiral stents were implanted intrabronchially through a standard left thoracotomy in 6 pigs weighing between 15 and 26 kg each. Macroscopically, the healing and tissue reactions around the stents were observed by repeated bronchoscopy. The histologic studies were performed when the pigs were killed after 6 months of follow-up. The stents were observed to be in the correct location 6 weeks postoperatively. At the time of death, all of the stents except one had disappeared. The bronchial wound had healed well in all animals and histology revealed normal scar tissue without any additional tissue reaction caused by the stent. This study showed that a bioabsorbable bronchial stent made of self-reinforced poly-l-lactide causes no adverse tissue reactions in the bronchial mucosa and should be investigated further. Intrabronchial stents made of self-reinforced poly-l-lactide could be suitable for treatment of bronchial stenosis.

Unusual forms of tracheobronchial compression in infants with congenital heart disease

Three groups of unusual forms of tracheobronchial compression caused by vascular anomalies are presented. Three patients had an encircling right aortic arch with a left-sided descending aorta and ligamentum arteriosum (group 1), two patients had airway compression caused by a pincer effect between a malposed and enlarged ascending aorta and the descending aorta (group 2), and three patients had airway compression after an arterial switch operation for transposition of the great arteries (group 3). Symptoms developed in all patients before the age of 4 months, and six of them had multiple failed attempts at extubation before the surgical intervention directed at relieving the airway compression. Fiberoptic endoscopy was used in all patients as a first-line diagnostic tool and was 100% accurate in establishing the diagnosis. The operations performed were aortic uncrossing in group 1, dissection and aortopexy of the right or left main bronchus in group 2, and dissection of the left main bronchus and lysis of adhesions in group 3. In group 1 there was one early death, resulting from aspiration, and one late death 4 years later, resulting from an unrelated cause. In this group, bronchomalacia was noted after the operation and resolved gradually in the year after the intervention. In group 2, one patient died of an aortobronchial fistula after placement of a bronchial stent. Group 3 patients had good postoperative results. Two of them are completely symptom-free and one has residual bronchomalacia and may need placement of a bronchial stent. (J T horac C ardiovasc S urg 1996;112:415-23)

Bronchial dehiscence after lung transplantation: correlation of CT findings with clinical outcome.

To determine whether computed tomography (CT) can help predict which patients will require surgical or bronchoscopic intervention during healing of bronchial anastomotic dehiscence after lung transplantation. The authors followed up 25 bronchoscopically proved dehiscent anastomoses through healing in 19 patients who underwent lung transplantation. CT findings were correlated with bronchoscopic results and clinical outcome. A bronchial defect and extraluminal air were initially present at CT in all 25 dehiscent anastomoses. Of 12 bronchial defects less than or equal to 4 mm, only one required intervention during healing (P < .05). Of 12 bronchial defects greater than 4 mm, six required intervention during healing. Eight of nine dehiscences with a tiny or small amount of extraluminal air healed with conservative treatment. Of 16 dehiscences associated with a moderate to large amount of extraluminal air, nine were treated conservatively and six required therapeutic intervention. Three healing anastomoses required bronchial stent placement. One patient died in the perioperative period. In patients with small dehiscences ( < 4mm) and patients with a tiny or small amount of extraluminal air, the anastomosis tends to heal without sequela. When patients have larger amounts of extraluminal air or larger ( > 4mm) dehiscences at presentation, CT cannot help predict which patients will require intervention.

Cardiopulmonary bypass in a post-lung-transplant patient

S INCE 1988, more than 250 lung transplantations have been performed at this mst~tutlon Some of these patients have subsequently required general anesthesia for a variety of surgical procedures including bronchial dilatation and stent placement. However, to the best of the author's knowledge, this is the first report of a patient who underwent cardiopulmonary bypass (CPB) after recovery from lung transplantation. This patient required CPB for repair of a type A aortic dissection 41⁄2 months after successful bilateral sequential lung transplantation. He had a prolonged and difficult hospital course after repair of the dissection. It is not known whether the transplanted lung is more vulnerable than normal to injury on CPB or to infection after CPB.

Surgical treatment of airway complications after lung transplantation

The treatment of dehiscence or stenosis of the bronchus after lung transplantation has to date consisted of endobronchial stenting or balloon dilation. Operative intervention has been limited to retransplantation with all its limitations. In our series of 121 anastomoses at risk, severe bronchial stenosis occurred in 11 (9%). In five instances the airway complications were treated surgically: two patients underwent retransplantation, one patient had a bilobectomy, and two required sleeve resection of the stenotic segment. All these procedures successfully removed the stenosis. This experience demonstrates that options other than bronchial anastomotic stenting and dilation may be successfully used to overcome posttransplantation anastomotic complications. Conventional resections may result in superior long-term graft function compared with retransplantation, avoiding the immunologically adverse effects of the latter procedure.

Bronchovascular sleeve resection: Technique, perioperative management, prevention, and treatment of complications

Between May 1989 and May 1992, we performed bronchial sleeve resections or complex reconstructions of the pulmonary artery in 55 patients. Forty-four patients had bronchogenic carcinoma, and 11 had benign lesions. One patient died (mortality 1.8%) and three (5%) had minor complications (dehiscence or granuloma), which were treated by laser recanalization and recovered within 1 year. Ten patients underwent sleeve resection of the pulmonary artery or reconstruction of the vessel with a pericardial patch with no complications. In patients with lung cancer, 2-year survival was 72%, whereas all patients with benign lesions were alive and well at 8 months to 3 years after the operation. We consider accurate surgical technique, bronchial protection with a pedicled intercostal flap, and the use of steroids in the postoperative period as the key factors for success. If anastomotic complications occur, these can be treated conservatively by laser recanalization and bronchial stenting.

The prevalence and management of bronchial anastomotic complications in lung transplantation

The prevalence and management of bronchial anastomosis complications have been assessed in a series of 53 patients undergoing lung transplantation. Of the 50 patients subsequently at risk of airway complications, these problems occurred in seven (14%). Only one patient died as a direct result of the airway complication (2%). Four patients required airway stenting, and their management is discussed. Although airway healing is normal in the majority of patients undergoing lung transplantation (86%), when deficits occur they can usually be successfully managed with conservative treatment. Bronchial stenting may be required on either a temporary or a permanent basis.