[Show abstract][Hide abstract] ABSTRACT: Background:
Surgery is an appropriate therapeutic approach for tracheal stenosis due to various benign and malignant conditions. When surgery is postponed for certain reasons, other options are chosen for airway patency. One alternative is using airway stents.
We aimed to introduce a safe method of tracheal polyflex stent placement in patients with tracheal stenoses.
Patients and methods:
During a 7-year period (2002 - 2008), polyflex stents were used 29 times among 20 patients for various indications. After encountering many difficulties in earlier cases, we gradually developed our new method and used it in most of our patients. In this method, without using large rigid bronchoscopes, the introducer tube could be used as a bronchoscope with the aid of a zero-degree lens and ventilating apparatus. In this method, the rate of possible trauma to the airway can be minimized by avoiding the use of thick rigid bronchoscopies and the stent can be placed faster and more accurately.
Polyflex stents were used in 11 men (55%) and 9 women with a mean age of 38.5 years. Stents were removed and changed in 12 cases and replaced with another type of stent in 3 patients. Indications were recurrence of tracheal stenosis (7), multisegmental tracheal stenosis (3), anesthesia limitations (3), tracheal tumors (2), dehiscence of tracheal anastomosis (1), severe inflammation of the tracheal mucosa (1), esophagobronchial fistula (1), and external pressure on the left main bronchus (1). In one patient, a stent was used to open a kinked Dumon stent as a temporary life-saving procedure. We found 6 cases of stent migration, 3 cases of granulation tissue formation, 1 case of infection, and 1 case of surgical site dehiscence.
Stents would be regarded as a temporary means of reaching the ideal condition for resection and reconstruction in most patients with tracheal stenoses. Although an optimal stent has not been introduced yet, we used polyflex stents in most of our patients with tracheal stenosis due to its availability and ease of use. We suggest that this method is safe and less time consuming than its traditional method of placement.
[Show abstract][Hide abstract] ABSTRACT: Because of the shortage of lungs for transplantation, finding the suitable lungs in brain-dead donors is an important issue. Recruitment maneuver is a strategy aimed at re-expanding collapsed and edematous lung tissue. The aim of this study was to assess the efficacy of this maneuver on improving marginal lungs for transplantation.
From 127 brain-dead potential donor which were evaluated for lung donation in Masih Daneshvari Organ Procurement Unit of Tehran, Iran, 31 (25%) had marginal lungs for transplantation. These donors had normal chest X ray or bilateral infiltration and had PaO2 200-300 mm Hg with FIO2 100%. The recruitment maneuver was performed and arterial blood gas was obtained before and after maneuver. The maneuver lasts for 2 hours with continuous check of O2 saturation and patient's hemodynamic during. Finally, patients with normal bronchoscopy and PaO2/FIO2 >300 mm Hg were considered good candidates for lung transplantation. The frequency (%) and mean ± SD were used for description of variables and the Wilcoxon test was used for comparison between pre- and post-maneuver PaO2 with FIO2 100%.
The mean ± SD of PaO2/FIO2 with 100% FIO2 of patients before and after recruitment were 239 ± 62 and 269 ± 91, respectively. Recruitment maneuver could convert 10 marginal lungs (32%) to appropriate ones (PaO2 > 300) and finally 8 lungs were transplanted.
Findings of this study showed that recruitment maneuver could convert inappropriate lungs to appropriate ones in one third of brain-dead patients who had marginal lung condition. So, it is recommended that this maneuver is considered in the assessment protocol of lungs for donation.
Full-text · Article · Dec 2013 · Transplantation Proceedings
[Show abstract][Hide abstract] ABSTRACT: In this study the anticorrosion performance of a two component water-based epoxy coating system is improved by using the 3-glycidoxypropyl trimethoxy silane (GPTMS). The structure of products is characterized by Fourier transform infrared spectrometer (FTIR). The formation of nanosiloxane coating is confirmed by dynamic light scattering (DLS) and Transition electron microscopy (TEM). EIS measurements also indicated an enhancement in protectiveness of water-based nanosiloxane epoxy coating against corrosion, which was characterized by higher coating resistances (Rc), and Z modulus at low frequencies .The improvement in adhesion properties of water-based nanosiloxane epoxy coating is explained by scanning electron microscopy (SEM) and Tapping-mode atomic force microscopy (AFM). Results of salt spray and adhesion tests showed that anticorrosive performance of water-based epoxy coatings improved by adding only 1 wt.% GPTMS to water based curing agent, which is equal with 27 wt.% of water-based epoxy coating.
No preview · Article · Jan 2012 · Surface and Coatings Technology
[Show abstract][Hide abstract] ABSTRACT: Management of thyroid cancers with laryngotracheal invasion is controversial.
A retrospective analysis of our database found 69 patients (38 females, mean age 59.6 ± 11.6) between March 1995 and July 2010; of them 42 (61%) were managed by non-resectional methods due to the extensive airway or regional involvement, severe co-morbidities, diffuse metastases or patient's preference. Segmental airway resection was performed in 27 (39%) patients; concurrent with thyroidectomy in 17 (Immediate group (IG)), and as a delayed procedure in 10 referred patients (Delayed group (DG)), who had previously undergone thyroidectomy with conservative airway management, like shaving procedures. Follow-up was completed in 81% of patients with a mean duration of 30 months.
Tracheal or laryngotracheal resection and reconstruction was performed in 18, laryngectomy in eight and pharyngolaryngectomy in one patient. There were two anastomotic dehiscence (11.1%), one resulted in mortality (3.7%). One or a combination of bronchoscopic core-out, laser, tracheostomy and stent placement was performed in 42 non-resected patients with two mortalities (4.7%). Overall 1-, 2-, 3- and 5-year survival was 85, 85, 68 and 49% in resected group, as well as 56, 46, 40 and 31% in non-resected group (P = 0.049), respectively. Among resected group, the overall 1-, 2-, 3- and 5-year survival was 92, 92, 76 and 61% in the IG as well as 75, 75, 56 and 28% in the DG (P = 0.43).
Complete segmental airway resection during or even after thyroidectomy could be safely performed, might be curative and may be associated with improved survival.
No preview · Article · Dec 2011 · European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery
[Show abstract][Hide abstract] ABSTRACT: Lung transplantation is the last treatment option for end-stage pulmonary diseases. Reviewing the characteristics of patients on the lung transplant waiting list is a helpful way to evaluate and prioritize the patients in need of special care. Because we have no information about mortality on the lung transplantation waiting list in Iran, the aim of this study was to evaluate the characteristics and survival rates of these patients.
The file of lung transplant candidates listed between 2005 and 2010 were evaluated for patient demographic data, type of disorder, waiting list time, and outcomes of death, transplantation, or alive.
The 131 patients on our list in this period revealed a mean age of 37±14 years with 86 (66%) males. The most common disorder among waiting list patients was pulmonary fibrosis (n=52; 40%). Among the 17 (13%) patients who were transplanted, most (35%) suffered from pulmonary fibrosis. The mean waiting time to transplantation was 17.2±11.8 months. Twenty-two patients (7%) died while on the waiting list. The mortality rate was unexpectedly highest among cystic fibrosis patients and then those with bronchiectasis. The mean survival time for all non-transplant patients based on the Kaplan-Meier method was 27.4 months and their 2-year survival rate was 74% based on life tables.
Although pulmonary fibrosis patients show the poorest survival on lung transplant waiting lists, in other countries, patients with cystic fibrosis and bronchiectasis displayed the worst survival on the Iranian list probably due to their poor rehabilitation and sputum evacuation. We concluded that it is necessary for every center to evaluate the characteristics of its patient cohort to match the activity according to the needs.
Full-text · Article · Mar 2011 · Transplantation Proceedings
[Show abstract][Hide abstract] ABSTRACT: Brain-dead patients are almost the only source of organs for lung transplantation, and lungs fall within the area of the least harvested organs. As a result, maintaining the highest possible harvest rate is a must for the lung transplantation system. In the present study, the harvest rate of lungs and also the causes of failure to donate the lungs is reported for brain-dead patients in our organ procurement unit.
After going through the brain-death database at our organ procurement unit between 2004 and 2008, we included all 93 brain deaths in this hospital. The lung donation rate was reviewed to examined the causes for failure to donate lungs.
From the total brain-dead patients registered in the database, only 4 (4.6%) patients donated their lungs. The causes of failure to donate a lung were not suitable lungs among 78 (83.8%) because they had an unacceptable oxygen challenge test results (<300 mm Hg). Another 11 patients had acceptable oxygen challenge test results, but donation failed in their case as well due to most frequently to pulmonary aspiration.
In this center, only a small percentage of lungs are appropriate for harvest in brain-dead patients, because many patients' lungs do not meet the criteria with unacceptable oxygen challenge test results. Patients with proper test results may fail to donate lungs due to pulmonary aspiration. More aggressive care of the patients may have an important role in keeping them in good condition and helping to preserve the organs for harvest. For this purpose, further training of intensive care unit staff and physicians are among the suggested steps to enhance the quality of care, which in turn can maximize the lung harvest rate.
[Show abstract][Hide abstract] ABSTRACT: Lung transplantation has evolved from an experimental procedure to a viable therapeutic option in many countries. In Iran, the first single-lung transplantation was performed in the year 2000, more than 3 decades after the first successful procedure in the world, and the first double-lung transplantation was performed in the year 2006.
To describe our 8-year experience in lung transplantation.
During 8 years, we performed 24 lung transplantation procedures. Underlying lung diseases were pulmonary fibrosis in 16 patients (66.6%); chronic obstructive pulmonary disease in 2 (8.3%); bronchiectasis in 5, including 2 patients with cystic fibrosis (20.8%), and alveolar microlithiasis in 1 (4.16%). Data for all patients were collected and analyzed. Procedures were carried out using standardized methods. The induction suppression regimen consisted of cyclosporine and methylprednisolone. Maintenance immunosuppression drugs were cyclosporine and mycophenolate mofetil, and tapering dosage of prednisolone. Patients were followed up with physical examinations, 3 times a week, as well as and cycle ergometry 3 times a week and spirometry and laboratory tests once a week and chest radiography per needed for up to 3 months posttransplantation.
The longest survival time was 7.2 years, in a 60-year-old patient with idiopathic pulmonary fibrosis. Fourteen patients died, 8 as a result of hemodynamic instability and/or hemorrhage, 1 as a result of bone and fat emboli, 3 after cessation of drug and 2 of them after infection.
Although lung transplantation is a complex procedure it can be performed in developing countries such as Iran.
[Show abstract][Hide abstract] ABSTRACT: Pulmonary artery stenosis after lung transplantation is a rare complication. It usually requires surgical correction but even after that the outcome is not favorable.
The patient was a 53-years-old woman who was candidate for lung transplantation surgery due to pulmonary fibrosis. After 7 months on waiting list, with severe limitations in daily living activities, she received a single lung transplant in 2007. The surgery was performed without any complication. One day after surgery and after extubation, the patient needed oxygen supplementation through mask with reservoir bag. In bronchoscopy, black-and-white exudate and black membrane that blocked the main bronchus in the transplanted lung was observed. By bronchial lavage the membrane and exudate were successfully removed and patient received antibiotics for documented Aspergillus infection and methylprednisolone pulse therapy for evidences of graft rejection. Despite success in treatments of the mentioned complications, the condition of the patient deteriorated and she became totally dependent to supplemental oxygen. Oxygen consumption level had increase and pulmonary artery pressure was increasing gradually. With suspicion to pulmonary artery stenosis, bronchial CT-Scan with contrast was performed 13 days after transplantation surgery which showed a 50% stenosis. Trans-esophageal echocardiography also showed a stenosis with 40 mmHg gradient. 18 days after transplantation surgery, percutaneous balloon angioplasty was performed which was initially successful but re-stenosis occurred. Seven days later, another balloon angioplasty with stent insertion was performed. After the procedure, the gradient has been removed. Patient was discharged 30 days after transplantation. Follow-up after 10 months revealed no stenosis and the stent was working properly.
Stent angioplasty can be performed with no problem or complication if pulmonary artery stenosis is seen after lung transplantation.
Full-text · Article · Feb 2009 · Annals of transplantation: quarterly of the Polish Transplantation Society
[Show abstract][Hide abstract] ABSTRACT: A number of postintubation tracheal stenoses involve different and separate segments. Treatment of these types of strictures is complicated with obscure results, infrequently reported in literature.
A total of 648 patients underwent treatment for tracheal or subglottic stenosis from September 1993 through October 2005; of those, 26 cases had two separate stenotic segments. Four types of therapeutic approaches were considered for these 26 patients: one-stage resection of the stenotic sites; two-stage resection of the stenotic sites; resection of one stricture and treatment of the second one by nonresectional methods such as dilatation, laser, stenting, T-tube, or tracheostomy; or treatment of both lesions by nonresectional methods. The therapeutic approach for each patient was determined by the surgeon and was based on the nature and location of stenoses, length of stenoses and the distance between the two stenotic sites.
There were 20 male patients (76.9%) and 6 female patients (23.1%), with a mean age of 23.9 years (range, 4 to 64). Fourteen patients had tracheal stenosis and 12 had both tracheal and subglottic involvement. Five patients underwent type 1 therapeutic approach whereas 4, 9, and 8 patients underwent types 2, 3, and 4, respectively. Mean length of resection was 58.9 mm in those who underwent complete resection of the stenotic sites (range, 30 to 90 mm). There were 2 complications, 1 stomal fistula and 1 wound infection. Follow-up was accomplished in all patients with a mean period of 21.5 months (range, 1 to 108). Sixteen patients achieved satisfactory results (good voice and airway), 7 are still under treatment (requiring stent, tracheostomy, or repeated dilatation), and 3 died (2 type 3 and 1 type 4). Two deaths were due to T-tube obstruction, and 1 was due to acute obstruction of the stenotic part.
Resection of both strictures and reconstruction of airway are feasible in some patients with multisegmental tracheal stenosis with good results. When resection of both strictures is not feasible, a combination of resectional and nonresectional managements could be helpful for the vast majority of patients.
Full-text · Article · Aug 2007 · The Annals of thoracic surgery