Distal Tracheal Segment Research Articles

Multiple costal cartilage graft reconstruction for the treatment of a full-length laryngotracheal stenosis after an inhalation burn

After suffering an inhalation burn, a 22-year-old male was intubated for seven days. Full-length massive scar formation in the upper airway necessitated tracheostomy five months later. After this, the stenosis became complete in the cricoid region, and a long cannula was needed to maintain the severely damaged middle-distal trachea. After unsuccessful laser dilatation, the more stenotic 3cm distal tracheal segment was resected, but two months later the stenosis recurred. As resection was ineffective, tracheoplasty was performed via a right-sided thoracotomy; the re-stenotized trachea was incised in length and successfully extended with 5cm long, oval-shaped rib cartilage. Three months later, the complete cricotracheal stenosis was fixed by combined laryngofissure and cricoid laminotomy with two 6cm×2.5cm cartilage pieces sutured into the incisions. The middle portion of the trachea was expanded with a similar graft inserted into the anterior wall below the tracheostomy. The fixing T-tube was removed three months later, and the patient had an adequate airway two years after the last procedure. We conclude that multiple cartilage graft reconstruction can be successful even after the development of an extremely long airway stenosis following inhalation burn injury.

Multiple Tracheal Resections and Anastomoses in a Blue and Gold Macaw (Ara ararauna)

A 1.5-year-old, male blue and gold macaw (Ara ararauna) was anesthetized for a health examination and blood collection. The following day it was returned for episodes of coughing. The bird was presented again 13 days after the initial presentation with severe dyspnea. A tracheal stenosis was diagnosed by endoscopy and treated by surgical resection of 5 tracheal rings and tracheal anastomosis. The bird was discharged but returned 2 days later with a recurrent stenosis. Bougienage and balloon dilation of the stenotic area were performed separately; each resulted in less than 48 hours' improvement in clinical signs after treatment. A second tracheal resection and anastomosis was performed, during which an additional 10 tracheal rings were removed. This second anastomosis was significantly more difficult to complete given the marked variation in diameter of the proximal and distal tracheal segments. The macaw recovered without complication and has had no recurrence of respiratory abnormalities 2 years after the second surgery. This report describes the longest total tracheal segment to be resected, followed by tracheal anastomosis, in a psittacine bird. The positive outcome in this case suggests that, when surgical therapy is elected, an aggressive approach is necessary to prevent recurrence of tracheal stenosis. In addition, macaws can recover well even after significant lengths of the trachea are resected.

Tracheal Reconstruction by Esophageal Submuscular Tunneling: An Experimental Study

The problem of how to treat large tracheal lesions remains a challenge in surgery. To reconstruct a long tracheal defect, a safe method other than end-to-end anastomosis is necessary. In 14 adult cross-breed dogs, a segment of trachea including seven tracheal rings was dissected and resected circumferentially. A submuscular tunnel was induced between mucosal and muscular layers of the adjacent esophagus lying right next to the trachea. An endotracheal tube was inserted between the tracheal rings 2 and 3. Then it was passed cautiously through the esophageal submuscular tunnel and through the distal tracheal segment. The proximal and distal ends of the esophageal tunnel and trachea were approximated and anastamosed. The animals were extubated 10 days after the operation. All dogs tolerated the surgical procedure well. The first two dogs experienced postoperative fever, tracheoesophageal fistula, aspiration pneumonia, and sepsis so hard bony components were omitted from diet. All survived animals were eating and barking well. The submuscular esophageal tunnel was patent in all animals. The new lumen was supported externally with fibrous connective tissue. The tunnelized area was covered completely with pseudostratified ciliated epithelium. Due to formation of fibrous tissue between skeletal muscular structures of the neck and the external layer of the tunnelized esophagus, the new airway remained patent. Overall, air tightness, good reepithelialization, and relatively no limitation of esophageal length are the advantages of tracheal reconstruction by submuscular esophageal tunneling. This new method is worthy of further investigation, as it is technically feasible and easy to implement.

Tracheal resection with primary anastomosis in cadavers: the effects of releasing maneuvers and length of tracheal resection on tension.

To determine the relationships among length of trachea resected, total tracheal length, and anastomotic tension when using various release maneuvers, we studied 10 adult human cadavers: 5 male and 5 female. The trachea was transected between rings 2 and 3. Precision, handheld spring tensiometers (Geneva Gage, LLC) were used to measure the tension required to approximate, and then overlap, the proximal segment relative to the distal segment, and the distal segment relative to the proximal segment after these maneuvers: no release, blunt dissection, neck flexion, suprahyoid release (SHR) without neck flexion, SHR with neck flexion, and right hilar release. After the tension measurements were recorded, the trachea was harvested and the total tracheal length was measured. Length-tension curves were plotted for both the superior and inferior tracheal segments after each release maneuver. The stiffness coefficient for the trachea and the resting load on the trachea following each release maneuver were calculated. An exponential length-tension relationship existed for the distal tracheal segment regardless of whether release maneuvers were performed. The proximal tracheal segment exhibited a linear length-tension relationship initially, but displayed an exponential relationship after SHR. We could resect 6.68 cm (range, 4.2 to 9.9 cm), 13.3 rings (range, 10 to 20 rings), or 65.5% (range, 42% to 100%) of the trachea without undue tension (<1,000 g) on the anastomosis. We conclude that various tracheal release maneuvers are effective in increasing the length of trachea that can be relatively safely resected. However, these maneuvers are not uniformly effective across subjects.

Regulation of secretion from mucous and serous cells in the excised ferret trachea

Mucus hypersecretion is an important characteristic of many airway diseases. Mucin is the major component of mucus, and is secreted from surface goblet cells of the airway epithelium and mucous cells of submucosal glands. Lysozyme is an enzyme secreted by serous cells of airway submucosal glands. We hypothesized that secretagogues acting through different pathways would have different effects on tracheal mucin and lysozyme secretion. We used a sandwich enzyme-linked lectin assay (ELLA) to measure mucin-like glycoprotein secretion and a spectrophotometric method to measure lysozyme secretion from isolated ferret tracheal segments. We evaluated the secretory response to four secretagogues; prostaglandin F 2α (PGF 2α), adenosine triphosphate (ATP), methacholine (MCh), and human neutrophil elastase (HNE). Each agent stimulated mucin and lysozyme secretion. The relative potency was PGF 2α≤ATP<MCh<HNE for mucin and ATP≤PGF 2α<MCh<HNE for lysozyme secretion. We showed that there is an anatomic gradient for constitutive and stimulated mucin and lysozyme secretion with the distal tracheal segments secreting more mucin and lysozyme per gram of tissue than the proximal segments. This robust model system can be used to evaluate the regulation of airway mucous and serous cell secretion and to assess the effect of agents that might alter the secretory response. We confirm that on an equimolar basis, HNE is one of the most potent mucus secretagogues.

Use of the linear stapler for pharyngoesophageal closure after total laryngectomy.

Use of the linear stapler for pharyngoesophageal closure after total laryngectomy.

Contractile Responses of Proximal and Distal Trachea Segments Isolated from Rats Subjected to Immunological Stimulation: Role of Connective Tissue Mast Cells

1. Anaphylaxis-induced contractions of proximal and distal tracheal segments isolated from 14-day ovalbumin (OA)-sensitized rats were studied. 2. OA-induced contractions in distal segments were significantly greater than those observed in proximal segments. 3. Pretreatment of the rats with compound 48/80 or with sodium cromoglycate (SCG) aerosolization significantly reduced OA-induced contractions of trachea distal segments, whereas the contractions of proximal segments were reduced only by compound 48/80. 4. Mepacrine reduced and indomethacin increased the OA-induced contractions in all tracheal segments. Nor-dihydroguaiaretic acid increased the OA-induced contractions in distal tracheal segments, whereas dazoxiben inhibited the contractions in these same segments; neither of these drugs had any effect on the contractions in proximal tracheal segments. 5. The depletion of connective tissue mast cells and subsequent in vitro treatment with indomethacin increased the OA-induced contractions in both segments. 6. We conclude that the contractions of tracheal muscle from OA-sensitized rats depends on the topographic and anatomical origin of the airway tissue. 7. Mediators released by connective tissue mast cells in proximal and distal segments play a pivotal role in this response and may account for variations in the intensity of contraction seen after the addition of OA.

Regulation of mucin secretion in the ferret trachea

Mucin is the major component of mucus and can be used as a marker for mucus secretion. The purpose of this study was to develop an in vitro method to evaluate the regulation of mucin secretion. To do this, we used a sandwiched enzyme–linked lectin assay to measure mucin secretion from isolated ferret tracheal segments. This assay entailed coating microtiter plate wells with dolichos biflorus agglutinin and detecting the bound mucin that was secreted into a buffer solution by the tracheal segments. We used this method to evaluate the secretory response to four secretagogues: prostaglandin F 2α (PGF 2α ), adenosine triphosphate (ATP), methacholine, and human neutrophil elastase (HNE). Each agent stimulated mucin secretion above baseline secretion (ATP [ p = 0.022], PGF 2α [ p = 0.009], and HNE [ p < 0.05]), and the relative potency of these secretagogues was PGF 2α ≤ ATP < MCh < HNE. We also demonstrated that there is an anatomic gradient for both constitutive and stimulated mucin secretion, with the distal tracheal segments secreting more mucin per gram of weight than the proximal segments. This fairly simple and reproducible technique can be used to evaluate the regulation of mucin secretion in the airway and to assess the efficacy of agents that might alter the secretory response. (Otolaryngol Head Neck Surg 1997;117:480-6.)

Regulation of Mucin Secretion in the Ferret Trachea

Mucin is the major component of mucus and can be used as a marker for mucus secretion. The purpose of this study was to develop an in vitro method to evaluate the regulation of mucin secretion. To do this, we used a sandwiched enzyme‐linked lectin assay to measure mucin secretion from isolated ferret tracheal segments. This assay entailed coating microtiter plate wells with dolichos biflorus agglutinin and detecting the bound mucin that was secreted into a buffer solution by the tracheal segments. We used this method to evaluate the secretory response to four secretogogues: prostaglandin F2α (PGF2α), adenosine triphosphate (ATP), methacholine, and human neutrophil elastase (HNE). Each agent stimulated mucin secretion above baseline secretion (ATP (p = 0.022), PGF2α (p = 0.009), and HNE (p &lt; 0.05)), and the relative potency of these secretogogues was PGF2α ≤ ATP &lt; MCh &lt; HNE. We also demonstrated that there is an anatomic gradient for both constitutive and stimulated mucin secretion, with the distal tracheal segments secreting more mucin per gram of weight than the proximal segments. This fairly simple and reproducible technique can be used to evaluate the regulation of mucin secretion in the airway and to assess the efficacy of agents that might alter the secretory response.

Tracheal Intubation Through Tracheoesophageal Fistula

Tracheal Intubation Through Tracheoesophageal Fistula

Distal tracheal stenosis in two children with double aortic arch and associated tracheomalacia

Two case reports are presented in children who developed significant respiratory distress due to persistent tracheomalacia despite vascular decompression for double aortic arch. Cardiopulmonary bypass is suggested as a useful approach to the distal tracheal segment in children.