Case series of Tracheal Surgery for Nontumoral Tracheal Stenosis : A single institutional experience

INTRODUCTION : Tracheal stenosis represents an emerging surgical problem seen with improvements in the understanding of airway management and respiratory mechanics. The most frequent type of large airway stenosis is due to iatrogenic events after or during tracheostomy or after orotracheal intubation and may be life threatening. The large airway stenosis usually results from prolonged ventilation from various causes like trauma, acute attacks of chronic respiratory disease, severe metabolic disorders, neurological disorders, cardiopulmonary disorders and postoperative ventilation. Since the 1960s, the steadily increasing use of endotracheal, tracheostomy, and cricothyroidostomy tubes for the management of secretions, prevention of aspiration and, most importantly, delivery of mechanical ventilatory support for respiratory failure have produced a spectrum of upper airway lesions that range in location from the nostril to the lower trachea, and in severity from pharyngitis to complete obstruction of the airway or asphyxiating hemorrhage. Endotracheal tubes cause pressure injury to the glottis, which can result in severe commissural scarring that is difficult to treat. Tracheotomy tubes can cause severe stomal stenosis in the trachea or infraglottic region. Both methods of airway intubation can result in pressure necrosis caused by the tube’s cuff, which is a preventable problem. The management of this disease is controversial, still not standardized or unified around the world because the role and efficacy of surgical techniques vs. endoscopic procedures strongly depend on the experience of the various centers and on referral pattern. We reviewed non-tumoral tracheal stenosis in 22 patients with special regard to the cause and various modalities of treatment of the stenoses in our institution. AIMS AND OBJECTIVES : 1. To study the epidemiology of post intubation tracheal stenosis. 2 To study the mode of presentation, method of diagnosis and pre-operative preparation. 3. To analyze the treatment options, surgical procedures, outcomes and results in patients with post intubation tracheal stenosis. PATIENTS AND METHODS : Setting. Department of Cardiothoracic Surgery, Government General Hospital,Chennai – 600 003. Design of The Study : Retrospective case Study. Period of The Study : January 2007 to April 2010. Ethical Clearance: Obtained from institute ethical committee. Inclusion Criteria: All patients diagnosed to have tracheal stenosis due to non-tumoral causes. Exclusion Criteria: - Patient with neoplastic lesions of upper airway and trachea. - Patients with poor respiratory reserve or marginal cardiac status. Investigations : CT NECK AND CHEST, Fiber Optic Bronchoscopy, Routine Pre-operative work up. All patients with tracheal stenosis admitted between Jan 2007 and April 2010 were retrospectively analysed and data collected. All patients’ clinical records and physical findings were reviewed for causal factors, diagnostic methods, surgical therapies, and outcomes. The initial diagnostic evaluation had included plain radiography, computed tomography, or both. The severity of the stenosis was classified as mild if less than 50% of the tracheal lumen was obstructed, moderate if the obstruction was 50% to 90%, or severe if 90% or more of the lumen was obstructed. Data including age of the patient, duration of ventilation, duration of onset of symptoms after ventilation, pre-operative investigations, intraoperative procedure, the site and nature of lesion, number of tracheal rings or length of tracheal segment excised, cause of stenosis and other epidemiological data were collected in the respective proforma and analysed. SUMMARY : Tracheal stenosis represents an emerging surgical problem seen with the steadily increasing use of endotracheal, tracheostomy, and cricothyroidostomy tubes for the management of secretions, prevention of aspiration and, most importantly, delivery of mechanical ventilatory support for respiratory failure. Cases of non-tumoral tracheal stenosis admitted between Jan 2007 and April 2010 in twenty-two patients at our institution were observed and data collected with special regard to the cause and various modalities of treatment of the stenoses and retrospectively analyzed. Over a 3-year period, 22 patients that included 19 male and 3 female patients, with an age range of 14–45 years (average 25.3 years) who had postintubation tracheal stenosis were admitted to the department of Cardiothoracic surgery at our hospital. The patients were treated with tracheal resection and primary anastomosis. The length of resected segment ranged from 1.5 to 4 cm. In 15 patients, the treatment result was good (68.2%). In 5 patients, the result was classified as satisfactory (22.7%). Trachea-to-trachea anastomosis was performed in 14 patients, trachea-to-cricoid anastomosis was performed in 5 patients, and laryngotracheal anastomosis in 1 patient. Laryngeal release was used in one patient with trachea-to-trachea anastomosis as the length of resected segment was long. The use of laryngeal release was dictated by the extent of resection and tracheal mobility in each patient. There were no operative or post operative deaths. There were no major life threatening complications observed. The principal complication observed in the patients was formation of granulation tissue to various extent at the anastomotic site. These patients were managed with laser vaporization of granulation tissue. Higher success rates can be obtained when patients are managed at a centre which routinely performs tracheal surgeries. The more complex the prior treatment, the more likely the eventual failure, even after reoperation. Early recognition and prompt referral to tertiary centers is vital for successful surgical outcomes. CONCLUSION : The good and satisfactory results of surgical treatment of postintubation stenosis (91%), even when it involves the subglottic larynx or in the presence of the rare TEF justify resection and reconstruction as treatments of choice. First operation is most likely to succeed and should ideally be performed by experienced hands in a specialized centre due to lower surgical success rate in patients who had prior failure of reconstruction. Higher success rates can be obtained when patients are managed at a centre which routinely performs tracheal surgeries. The more complex the prior treatment, the more likely the eventual failure, even after reoperation. Early recognition and prompt referral to tertiary centers is vital rather than repeated attempts at tracheostomy involving a normal tracheal segment. T tubes, inlying stents, and laser treatment may be applicable in a limited spectrum of lesions and at a much lower level of long term success. The complication rate is generally low for tracheal lesions. Serious sequelae more often follow laryngotracheal resections. The most common late complication is the formation of granulations at the suture line and can usually be managed with bronchoscopic removal or LASER vaporization

Collecting Genetic Resources of Major Forage Grasses in India: Progress and Future Strategies

Indian gene centre possesses rich genetic and species diversity in native forage grasses (1256 spp.), as about one third of them, chiefly belonging to the tribes namely Andropogoneae, Paniceae and Eragrostideae, are of forage importance (Handbook of Agriculture, 2009). Forage grasses are important source of livestock feed. Collecting genetic diversity in major native forage species, occurring in both wild (mostly in rangelands) and cultivated state, is of paramount importance in conservation and use. Considerable genetic variability has also been generated in some introduced forages (e.g. Panicum maximum, Brachiaria spp.) as a result of repeated introductions followed by acclimatization due to cultivation under various climatic conditions of India. Since inception in 1976, ICAR-NBPGR has been nodal organization at country level for survey, exploration, collection, characterization, documentation and conservation of plant genetic resources (PGR) viz., landraces of crops, their wild relatives, and other economic plants including forages

Legumes of Forage Value: Their Diversity and Priority for Collection in India

Indian subcontinent is a megacentre of agro-diversity. Legumes have a special place with several native crops and economically important species occurring along forest margins and openings, pastures, grasslands and grazing lands. Several are dual-purpose species for food and feed. However, herbage legumes though major components of grasslands and with a major role in their quality and improvement lack persistence as compared to grasses and their collection, maintenance and conservation assumes importance in the wake of change and loss of habitats of native species and introduction of new germplasm with forage potential. Establishing the correct identity of species is therefore a priority. The major forage legume crops of India (Anon., 2013) belong to Tribes Trifolieae- Trifolium, Medicago, Melilotus among temperate legumes; Phaseoleae- Vigna; and Indigofereae- Cyamopsis tropical, subtropical and arid conditions (Arora and Chandel, 1972). These have a good representation of erect, spreading and viny species with potential for use as forage, soil improvement and use as green manure and often with non-toxic herbage and successfully grown over widely varying environmental conditions making this a morphologically variable and highly diverse germplasm resource. Collecting species of native and introduced species from these habitats that are in a state of flux is important for locating potentially important and unique diversity well adapted to the areas of occurrence. Several species of forage legumes, both native and introduced (Nayar et al., 2014) were represented as reference specimens of plants collected from the wild or grown in experimental conditions at the National Herbarium of Cultivated Plants (acronym: NHCP). An initiative undertaken was to authenticate the identity of these, and work out characters that could be used for field identification

Clustering Images Using the Latent Dirichlet Allocation Model

Clustering, in simple words, is grouping similar data items together. In the text domain, clustering is largely popular and fairly successful. In this work, we try and apply clustering methods that are used in the text domain, to the image domain. Two major challenges in this approach are image representation and vocabulary definition. We apply the bag-of-words model to images using image segments as words. We use the Latent Dirichlet Allocation (LDA) to model the relationships be-tween “words ” of an image, and between images. This provides us with a highly compressed yet succinct representation of an image, which can be further used for various applications like image clustering, image retrieval and image relevance ranking. In this work, we have used the relationships obtained from LDA to cluster the images with 78 % success.

Wild edible plants used by Konyak tribe in Mon district of Nagaland: Survey and inventorisation

74-81<span style="font-size:11.0pt;font-family: " times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">This paper deals with 41 species of wild edible plants (WEPs) used by Konyak tribe in Mon district of Nagaland, recorded in two survey-cum-exploration trips undertaken during 2013 and 2014. The scientific and vernacular names of the plants, trends in domestication, period of availability, part(s) used and related notes are provided. Investigation for ethnobotanical studies and nutritive analysis has been emphasised. Fifteen WEPs were prioritised for germplasm collection and conservation.</span

Wild edible plants used by Konyak tribe in Mon district of Nagaland: Survey and inventorisation

This paper deals with 41 species of wild edible plants (WEPs) used by Konyak tribe in Mon district of Nagaland, recorded in two survey-cum-exploration trips undertaken during 2013 and 2014. The scientific and vernacular names of the plants, trends in domestication, period of availability, part(s) used and related notes are provided. Investigation for ethnobotanical studies and nutritive analysis has been emphasised. Fifteen WEPs were prioritised for germplasm collection and conservation

An occurrence of Indo-Chinese taxon Momordica subangulata Blume subsp. subangulata (Cucurbitaceae) in Nagaland: a new distribution record from India

Momordica subangulata Blume subsp. subangulata collected from Tuensang district of Nagaland forms a new distributional record for India. Earlier, this taxon was reported from Indo-China (Mainland Southeast Asia) and southern China. Its description, phenology, ecology, relevant notes and uses are presented. </div

Trans situ conservation strategies to conserve the extinction risk species, Sesamum prostratum Retz., a crop wild relative of sesame being endemic to coastal strand habitat: a case study

Coastal strands ecosystem is a narrow strip of land adjacent to seashore and is often prone to natural or man-made disturbances. Conserving the endangered and endemic plant species having coastal strands as their niche habitat is challenging and requires special conservation drives. One such endemic species along the coastal strands of Indian sub-continent (Eastern coasts of Southern India and Sri Lanka) is the potentially saline tolerant crop wild relative (CWR) of sesame, Sesamum prostratum Retz. In our recent collecting expedition for this species, we have reported the dwindling nature of this species’ occurrence and a risk assessment for this species as per the IUCN guidelines underscored to be of critically endangered (CR) category. The IUCN had already declared this endemic species as CR in Sri Lanka during 2012. Using this as a case study for the way forward, we discuss here on the appropriate management measures that can be taken up to efficiently conserve the endemic species of disturbed habitats to prevent them from the risk of extinction through suitable conservation measures. Importance of CWRs in crop improvement through trait introgression and crop diversification through de novo domestication events are demonstrated in rice and tomato using gene editing tools. Potentialities of the trans situ conservation measures, the most appropriate, to avoid further decline in the occurrences of S. prostratum Retz., and its applicability for other threatened (endemic) species of fragmented habitat is also discussed