An experimental study on viability of the devascularized trachea

This experiment was designed to evaluate the effect of varying extents of devascularization to the viability of the trachea, and the influence of preservation of the right bronchial artery on the ischemia of the widely devascularized trachea. In experiment 1, the canine trachea was devascularized in a stepwise manner, and the regional blood flow was measured in each situation. This experiment revealed that the regional blood flow decreased to one-third of the non-treated trachea when the bilateral bronchial arteries were transected, and to nil when the cervical and mediastinal trachea was devascularized. In experiment 2, in which dogs were divided into 2 groups depending on preservation of the right bronchial artery, the trachea was stepwisely devascularized and the regional blood flow measured. This experiment indicated that the regional blood flow in the trachea when the right bronchial artery was preserved did not so remarkably diminish, though the cervical and mediastinal trachea was devascularized. In experiment 3, dogs were divided into 3 groups according to the extent of devascularization of the trachea and to the presence or absence of the preserved right bronchial artery, and were followed for 2 months postoperatively. This experiment demonstrated that the preservation of the right bronchial artery prevented tracheal necrosis caused by devascularization of the cervical and mediastinal trachea. We concluded that the regional tracheal blood flow markedly decreased and that tracheal necrosis occurred following devascularization of the cervical and mediastinal trachea when the bilateral bronchial arteries were transected. The preservation of the right bronchial artery however, prevented a decrease in the regional blood flow and necrosis of the widely devascularized trachea.