We reported a case in which thoracoscopic plication of the membranous portion was performed instead of the use of foreign substances for tracheobronchomalacia in an elderly individual.
For tracheobronchial extracorporeal fixation, Nissen et al. described an operation using autologous ribs [6], and Herzog et al. described an operation using the rectus abdominal muscle sheath [7]. Subsequently, Wright et al. reported on extra-membranous external fixation using a polypropylene mesh [8. 9]. In this technique, in addition to direct fixation of the membranous portion with a polypropylene mesh, the scar tissue grows, and the polypropylene mesh is integrated into the membranous portion to increase its stability and to maintain airway lumen patency [5]. Thus, fixation of the membranous portion with stabilizing materials, such as polypropylene meshes [8, 9] or polytetrafluoroethylene sheets [10], is the most common approach in recent years. In our case, after applying PGA sheets on the membranous portion, the area around the membranous portion was covered with thick scar tissue at 6 months after the operation although stabilizing materials were not used, and this also led to the stability of the membranous portion. The fixation was adequate, and restenosis was not observed. The suturing may cause restenosis long term; however, it is considered appropriate when performing lifesaving surgery in the elderly.
Indications for surgical treatment of tracheobronchomalacia include the absence of irreversible respiratory disorders, such as chronic obstructive pulmonary disease (COPD), and any other underlying disease that could complicate surgery. However, Ernst et al. reported the effectiveness of extra-membranous fusion using a polypropylene mesh for tracheobronchomalacia associated with severe emphysema. According to their report, airway stabilization is indicated in patients whose respiratory condition is improved by placing a silicone stent [11]. In the present case, assuming that the adjustable-length tracheostomy tube was equivalent to stent placement, it would have been considered an indication for surgery, because spontaneous breathing was possible by the placement of the adjustable-length tube.
In addition, this procedure is commonly performed using a conventional posterolateral approach. Most reports on this approach indicate that foreign materials such as polypropylene meshes [8, 9] are attached to the membranous portion. We aimed to reduce the invasiveness of the operation compared to that of the conventional posterolateral approach by performing it under thoracoscopy. The outcome of this less invasive, safer approach suggests that more patients can undergo this surgery. Additionally, we chose to avoid the use of foreign materials because MEPM-resistant Pseudomonas aeruginosa had been detected in the central airway. Hence, we decided to plicate the membranous portion with horizontal mattress sutures using absorbent threads at both ends of the needle and use only PGA sheets and fibrin glue for fixation. This method was adopted from the report by Masaoka et al. and modified [3]. We used horizontal mattress sutures in order to avoid tissue damage as much as possible and to increase the suture density to obtain a reliable forming effect. This method is advantageous because it avoids the use of foreign materials, and the procedure is simpler and easier to perform under thoracoscopy compared to establishing stabilization using a mesh. Although this method is considered useful for the crescent type of tracheobronchomalacia, it is necessary to fix the left and right cartilage parts for the saber-sheath type; hence, it is necessary to fix the trachea by a prosthesis.
First, we separated the lung ventilation by inserting an extra-long, single-lumen tube using an occlusion balloon, because the double-lumen tube was too large and could potentially be damaged by the suturing [9]. However, because the patient had COPD, the right lung was not sufficiently collapsed. Posterolateral thoracotomy allows for the surgery to be performed while isolating the lung that cannot be collapsed. In contrast, when performing thoracoscopic surgery, the single-lumen tube provides insufficient collapse of the lung. Thus, we provided unilateral lung ventilation with a double-lumen tube and carbon dioxide insufflation to create a sufficient operative field. Nevertheless, care must be taken to prevent damage to the tube-cuff during suturing. In addition, there have been several reports on azygous vein ligation and division [9, 12]. However, using the thoracoscopic field of view, the posterior aspect of the azygous vein could be sutured without tension.
However, because the cervical trachea cannot be visualized using a transthoracic approach, a tracheostomy or a permanent stent may be required when treating patients in whom malacia or stenosis extends to the cervical trachea.
