Length Of Trachea Research Articles

Split transplantation of the trachea: A new operative procedure for extended tracheal resection

Before tracheal transplantation can be applied clinically, several problems must be solved: immunosuppression, blood supply to grafts, and reliable long-term preservation of grafts. We have conducted experiments on tracheal transplantation to solve these problems. In the present study, we tried a new operative procedure to accomplish reliable revascularization of transplanted tracheal grafts. It has been reported that transplantation of a 10-ring length of trachea is difficult even with omentopexy. Long tracheal allografts can be transplanted with use of direct revascularization, but this technique is extremely troublesome. Thus we developed a new operative procedure, “split tracheal transplantation,” in which grafts are divided at the midportion and covered with omentum, after demonstrating that the blood supply to tracheal grafts can be reestablished around the suture lines. Two groups of dogs were used. In group A (control, n = 4), a 10-ring length of trachea was autotransplanted. The anastomotic sites and grafts were covered with omental pedicles. In group B (split tracheal transplantation, n = 10), tracheal grafts 10 rings long were autotransplanted. These grafts were divided at the midportion, a piece of omentum was inserted between the two halves, and the midportion was sutured. Grafts were observed regularly by bronchoscopy and examined histopathologically after the animals died or were killed. In some animals, microangiography of the bronchial circulation was done. In the control group, necrosis, stenosis, or malacia of the grafts was observed in three of the four animals. In the split transplantation group, all animals survived for at least 2 months, all grafts were incorporated, and none showed ischemia, stenosis, or malacia. Microscopic examination and microangiography revealed that neovascularization of the graft was promoted by omentum inserted at the midportion of the graft. Split transplantation of the trachea is an easy and reliable way to extend tracheal resection. (J T horac C ardiovasc S urg 1996;112:-8)

Modeling steady-state inert gas exchange in the canine trachea

The functional dependence between tracheal gas exchange and tracheal blood flow has been previously reported using six inert gases (sulfur hexafluoride, ethane, cyclopropane, halothane, ether, and acetone) in a unidirectionally ventilated (1 ml/s) canine trachea (J. E. Souders, S. C. George, N. L. Polissar, E. R. Swenson, and M. P. Hlastala. J. Appl. Physiol. 79: 918-928, 1995). To understand the relative contribution of perfusion-, diffusion- and ventilation-related resistances to airway gas exchange, a dynamic model of the bronchial circulation has been developed and added to the existing structure of a previously described model (S. C. George, A. L. Babb, and M. P. Hlastala. J. Appl. Physiol. 75: 2439-2449, 1993). The diffusing capacity of the trachea (in ml gas.s-1.atm-1) was used to optimize the fit of the model to the experimental data. The experimental diffusing capacities as predicted by the model in a 10-cm length of trachea are as follows: sulfur hexafluoride, 0.000055; ethane, 0.00070; cyclopropane, 0.0046; halothane, 0.029; ether, 0.10; and acetone, 1.0. The diffusing capacities are reduced relative to an estimated diffusing capacity. The ratio of experimental to estimated diffusing capacity ranges from 4 to 23%. The model predicts that over the ventilation-to-tracheal blood flow range (10-700) attained experimentally, tracheal gas exchange is limited primarily by perfusion- and diffusion-related resistances. However, the contribution of the ventilation-related resistance increases with increasing gas solubility and cannot be neglected in the case of acetone. The increased role of diffusion in tracheal gas exchange contrasts with perfusion-limited alveolar exchange and is due primarily to the increased thickness of the bronchial mucosa.

Steady pressure-flow relationship of a model of the canine bronchial tree.

Static pressure differences (deltaP) across the entire length and portions of a latex reproduction of a canine bronchial tree were measured during steady inspiratory or expiratory flow (V). The reproduction consists of a 10-cm length of trachea through bronchi of about 2 mm in diameter. The airflow was simulated by a water flow with tracheal Renolds number (Re0) in the range from 1,500 to 10,000. Loss in total pressure (deltaPt) was computed by summing deltaPt and V were well described (r greater than 0.98) by a dimensionless Rohrer equation deltaPt/deltaPd0 = A + B Re0 applicable to gas flow, in which deltaPd0 is a Poiseuille pressure drop. For expiratory deltaPt, A was about twice that for inspiration, while the values for B were nearly equal. Differences in kinetic energy between sites of static pressure measurement are important in determining loss in total pressure. Rohrer's equation is a good approximation to the phenomenological laws of steady inspiratory and expiratory flow-pressure relations in the canine bronchial tree for the range of Reynolds number investigated.

Biomechanics of the giraffe larynx and trachea.

Despite possession of a well developed larynx and a gregarious nature, the Giraffe is able to utter only low moans or bleats. Morphological and histological examination, together with measurements of trachea and subglottic area, on three fresh larynges (Giraffa camelopardalis) has made it possible to explain the lack of vocal power. Factors such as thoracic expiratory flow rate, length of trachea and recurrent laryngeal nerves, together with morphological details of vocal folds, and intrinsic laryngeal muscles have all been considered, providing a unique example of the relationship between morphology and function in the mammalial larynx.

Cadaveric Length of Trachea in Bangladeshi Adult Male

Context: Anatomical knowledge about length of trachea is essential for anesthetists, surgeons, radiologists & sonologists. In anesthetic procedure, the knowledge of the length of trachea helps to select correct sizes of endotracheal tubes. Study Design: A descriptive type of study. Place and period of study: The study was carried out in the Department of Anatomy, Sir Salimullah Medical College, Dhaka, from July 2006 to June 2007. Materials: 47 trachea of Bangladeshi adult male, age ranged from 20 to 58 years within 24 hours after death which were autopsied in the Department of Forensic Medicine of Sir Salimullah Medical College & Dhaka Medical College, Dhaka. Method: The collected samples were divided into four age groups, ranged from 20 to 58 years and comparative studies were done between different age groups. Result: The length of trachea increased with advancing age. The values showed positive correlation with age & statistically was highly significant (P<0.001). Conclusion: In the present study the length of the trachea increased with the increasing age. Further study with large sample size is required to make standard data for Bangladeshi adult male. Key words: Trachea, Length. doi: 10.3329/bja.v7i1.3024 Bangladesh Journal of Anatomy January 2009, Vol. 7 No. 1 pp. 42-44

Tracheal reconstruction: an experimental study.

During the past two decades experimental and clinical trials yielded valuable information concerning tracheal reconstruction with grafts and prostheses. 1-46 A completely satisfactory method for replacement of a resected length of trachea, however, is yet to be realized. The purpose of this study was to investigate the use of lyophilized (freezedried) tracheal homografts (Fig. 1), with and without tantalum mesh support (Fig. 2), and of fresh autogenous split-thickness skin grafts supported with tantalum mesh

Tracheal homografts in dogs.

Introduction and Aims There is no satisfactory method to replace the entire circumference of a diseased or stenotic length of trachea with either a graft or a prosthesis. The need for such a method is evident when one considers the increasing incidence of (1) traumatic injury of the trachea resulting from automobile accidents and military actions, (2) primary and secondary neoplasms of the trachea, and (3) stenosis of the trachea following chronic infections. It was the purpose of this project to devise such a method, utilizing tracheal homografts wrapped with tantalum mesh gauze. History The recent advances in vascular surgery using homografts to replace diseased portions of major arteries has stirred interest in the possibility of similar procedures as applied to the trachea. Even before this current emphasis, several investigators had done basic work in studying the manner of tracheal repair. 1-7 In addition to tracheal homografts many other materials