Artificial Trachea Research Articles

Clinicopathologic study of thyroid carcinoma infiltrating the trachea.

Eighteen patients (10 women and 8 men), ranging in age from 37 to 80 years, with thyroid carcinoma infiltrating the trachea comprised this series. Eleven had primary and 7 had recurrent cases. Total laryngectomy was performed in 4 patients, and tracheal resection was carried out followed by end-to-end anastomosis in 13 patients. In one patient, reconstruction was done with Naville's artificial trachea after tracheal resection. Eleven patients were alive after 1 year and 8 months to 6 years and 7 months after the operation. This result was significantly better than that of a group of ten patients without resection of the infiltrated trachea (seven patients died within 6 months). Thus, combined resection of the upper airway improved the prognosis of advanced thyroid carcinoma with tracheal infiltration. Histologic examination of surgical specimens demonstrated well-differentiated carcinoma in seven patients, poorly differentiated carcinoma in seven patients, undifferentiated carcinoma in three patients, and squamous cell carcinoma in one patient. The result showed a higher frequency of poorly differentiated carcinoma than in the control group of 70 patients without tracheal infiltration.

LABORATORY EVALUATION OF LOW-PRESSURE TRACHEAL TUBE CUFFS: LARGE-VOLUME V. LOW-VOLUME

Large- and low-volume low-pressure tracheal tube cuffs were compared during exposure to nitrous oxide. The compliance of both types of cuff when measured inside and outside an artificial rigid trachea, the volume of intubated cuff, the residual volume, the nitrous oxide diffusion time, and the specific diffusion rate of the cuff membrane to nitrous oxide were measured in the laboratory. From these variables, the diffusion rate of nitrous oxide, the surface area available for nitrous oxide diffusion, the tracheal wall pressure exerted by cuff, and the degree of folding of the intubated cuff were derived. The results showed that the rapid increase in pressure of the large-volume cuff when intubated was caused by low compliance, the large surface area available for nitrous oxide diffusion, and the considerable permeability of the cuff membrane to nitrous oxide.

Kinetic energy loss and convective acceleration in respiratory resistance measurements

Endotracheal tube (ETT) resistance measured in isolation may differ from the effective ETT resistance in vivo. Much of this difference results from the dissipation of kinetic energy near regions of abrupt cross-sectional area change at the end of the ETT. Measurements made on an artificial ETT-tracheal model illustrate that effective ETT resistance is variable and dependent on the size of the artificial trachea. These experimental results are consistent with aerodynamic theory and suggest that one cannot assume that ETT resistance measured in isolation will be the same as the effective ETT resistance in vivo.

The pathophysiological effect of Syngamus trachea infection in turkeys

An attempt was made to assess the pathophysiological effect of an artificial Syngamus trachea infection in turkeys by the use of 125I-labelled albumin and 51Cr-labelled red blood cells. Plasma volume, albumin pool and albumin distribution, and albumin catabolism were determined. No evidence of significant blood loss was found. A significant increase of globulins resulted in elevation of total serum proteins, while the albumin level remained steady. The fractional catabolic rate of albumin in infected birds showed a slight increase over the period 7 to 14 days after infection.