Intraoperative Aortic Dissection during Lung Transplantation in a Patient with Alpha-1 Antitrypsin Deficiency.

Alpha-1 antitrypsin deficiency (AATD) is an inherited disorder affecting the lung, liver, and rarely skin. The most frequent features of AATD consist of chronic lung disorders related to protease-antiprotease imbalance in the respiratory system, to which lung transplantation is frequently indicated. We describe a case of aortic dissection in a 55-year-old male who underwent left single lung transplantation for respiratory failure due to AATD-related emphysema. Extracorporeal membrane oxygenation (ECMO) was indicated during the procedure, and an arterial cannula was placed into the descending aorta and a venous cannula was placed into the right femoral vein. Bronchial and vascular anastomoses were finished without any problems and ECMO was weaned off However, transesophageal echocardiography carried out at the end of the operation showed a dissected descending aorta. Alpha-1 antitrypsin (AAT) is the major serum inhibitor of seine proteinases, which enzymatically destroys collagen and elastin. Degeneration of connective tissues, in particular elastic tissues, is established in AATD, and decreased stiffness of the aorta due to degradation of elastic fibers has also been reported in AATD. In this patient, reduced AAT activity might have boosted the enzymatic destruction of his arterial walls, leading to enhanced vulnerability to aortic dissections.

Anesthetic management of nonintubated video-assisted thoracoscopic surgery using epidural anesthesia and dexmedetomidine in three patients with severe respiratory dysfunction.

Nonintubated video-assisted thoracoscopic surgery (VATS) has been reported to be safe and feasible for patients with various thoracic diseases, including those who have respiratory dysfunction. In nonintubated VATS, it is important to maintain spontaneous respiration and to obtain a satisfactory operating field through adequate collapse of the lung by surgical pneumothorax. Therefore, we need to minimize the patient's physical and psychological discomfort by using regional anesthesia and sedation. If analgesia and sedation are inadequate, conversion to intubated general anesthesia may be required. Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist that provides anxiolysis and cooperative sedation without respiratory depression. It seems to be a suitable sedative for nonintubated VATS, especially in high-risk patients for intubated general anesthesia, but there have been no report about its use combined with epidural anesthesia in nonintubated VATS for adult patients. Here, we report three patients with severe respiratory dysfunction who underwent nonintubated VATS for pneumothorax using epidural anesthesia and DEX. In all three patients, DEX infusion was started after placement of an epidural catheter and was titrated to achieve mild sedation, while maintaining communicability and cooperation. This seems to be a promising strategy for nonintubated VATS in patients with respiratory dysfunction, as well as patients with normal respiratory function.