Chapter 71 Cervical Tracheal Resection and Reconstruction

INTRODUCTION

A wide variety of conditions cause anatomic or functional narrowing of the trachea. The most efficient and effective treatment for most of these conditions is tracheal resection with subsequent end-to-end anastomosis (TR). Techniques have been standardized since the 1960s to allow these procedures to be performed with excellent results and low morbidity and mortality. Release techniques have been developed that frequently allow even long segments to be resected with the creation of a tension-free anastomosis that will usually heal without incident. However, even in the most experienced hands, TR can engender a variety of complications—some of which are emergent and life threatening.

This chapter reviews the basic operative steps of TR and the complications that can be encountered as they relate to each step. The management of each complication is presented as well as technical details that can be followed in order to try to prevent the complication from occurring. I focus upon “simple cervical tracheal resection”—the excision of a segment of the upper trachea, not including the cricoid cartilage or higher, carried out through a curvilinear neck incision just above the jugular notch. More complex resections including the larynx or the distal trachea approaching the carina, though utilizing many of the same basic principles, require somewhat different and more advanced techniques that are beyond the scope of this chapter. Further, it has been established that as the anastomotic level ascends, a progressive increase in complication rate occurs: failure rates rise from 2.2% for trachea-trachea anastomosis to 6.0% for trachea-cricoid anastomosis to 8.1% for trachea–thyroid cartilage anatomosis.¹

Two centers pioneered the techniques of TR that are now in standard use around the world: these are the groups formerly headed by Hermes Grillo at the Massachusetts General Hospital (MGH) and by Griffith Pearson at the Toronto General Hospital. Because I am more familiar with the methods and results of the MGH group, having trained with Grillo, I focus upon their techniques and their published results in reporting the incidences of the various complications.

INDICATION

• Tracheal stenosis in upper third of trachea caused by prior tracheostomy or endotracheal intubation, inflammatory disorders, or tumors

OPERATIVE PROCEDURE AND COMPLICATIONS

Rigid Bronchoscopy with or without Dilation

Rigid bronchoscopy is nearly always performed immediately prior to TR for a variety of reasons. First, the view of the mucosa with a Hopkins lens system passed via a rigid bronchoscope is superior to that obtained through a flexible bronchoscope, therefore, decisions regarding whether acute inflammation has resolved and whether or not there is any need to delay the procedure can be made most accurately. Second, measurements of the length of the stenosis, the distance from the distal end of the stenosis to the carina, and the distance from the proximal edge of the stenosis to the vocal cords can be made most accurately with a rigid scope.

The most important reason for carrying out rigid bronchoscopy immediately preoperatively, however, is the frequent need for tracheal dilation immediately prior to the procedure. One would like to pass at least a size-5 and preferably a size-6 endotracheal tube (ETT) beyond the stenosis prior to positioning and operation so that the airway is secure and the dissection can proceed without undue haste up to the point of initial airway division. In situations in which a size-6 tube cannot be passed because of the tight nature of the stenosis, progressive dilation with rigid scopes will generally allow passage of such a tube.

The technique of dilation involves beginning with a scope with a diameter only slightly larger than the visible tracheal lumen (Fig. 71-1). This bronchoscope is passed through the stenosis and deeply into the airway, and it is held there for at least 1 minute as the stenosis is stretched, maintaining ventilation through the bronchoscope. A scope that is 0.5 to 1 mm larger is passed next, and the procedure is repeated until the lumen is sufficiently large to pass the ETT. For a critically tight stenosis, one can use Jackson dilators passed through the bronchoscope initially until the lumen is large enough to pass the tip of the scope itself.

Figure 71-1 Bronchoscopic view of a postintubation tracheal stenosis just prior to dilation with the rigid bronchoscope through which the stenosis is seen. Dilation is performed to allow placement of an endotracheal tube (ETT) prior to resection. It is done by stretching the stenosis with serially larger rigid bronchoscopes.

Preoperative Loss of Airway

Circumferential Dissection of the Involved Portion of the Trachea

After the curvilinear cervical skin incision has been made, subplatysmal flaps are mobilized down to the jugular notch and up to the thyroid cartilage, and the anterior wall of the trachea is exposed by division of the thyroid isthmus. The critical portions of the operation are then begun. In many cases, the distal extent of the internal stenosis can be seen by thickening and scar tissue visible on the external surface noted during mobilization. When this line is unclear, a flexible bronchoscope can be introduced from above, and its light or visualization of a needle passed into the lumen from without can be used to demonstrate the distal extent to the operating surgeon. A fine suture is placed on the external tracheal surface at this level to indicate the extent of mobilization required and the ultimate point of distal division.

The involved region of trachea is then mobilized first from its lateral, vascular attachments, then from the posterolaterally placed recurrent laryngeal nerves, and finally from the esophagus, which is closely apposed to the posterior, membranous tracheal wall. A Penrose or red rubber drain can then be placed around the trachea (Fig. 71-2). Almost all of the circumferential dissection is carried out sharply. In some cases, when there is little scarring or inflammation, circumferential dissection of virtually the entire involved segment can be done prior to airway division. In most situations, however, I mobilize only the most distal portion of the involved airway circumferentially, leaving the posterior dissection of the more proximal portion from the underlying esophagus for after the division of the airway distally. After this distal division has been carried out, the proximal segment to be resected can be progressively lifted up, facilitating its dissection away from the nerves and esophagus (Fig. 71-3). It is critical that circumferential dissection be taken only about 5 mm beyond what will become the margins of resection in order to maximally preserve blood supply to the anastomosis (see the section on “Anastomosis,” later).

Figure 71-2 Typically, one first dissects the trachea circumferentially only at the distal end of the diseased area. A Penrose or red rubber drain is then passed around the trachea in this location.

Figure 71-3 After placing distal, midlateral stay sutures of 0-0 Vicryl and withdrawing the ETT, sharp division is carried out with a scalpel. From this point on, cross-table ventilation is carried out. Next, the proximal involved segment of trachea is dissected more proximally away from the esophagus and recurrent nerves until the proximal point of division is reached.

(From Grillo HC. Surgery of the Trachea and Bronchi. United States, BC Decker, Inc; 2004.)

Recurrent Nerve Injury

• Consequence

Injury to one recurrent laryngeal nerve will cause hoarseness, but it may also cause incomplete airway compromise and swallowing dysfunction that can lead to aspiration. A nerve is sometimes injured or stretched but not actually divided; in this case, its function may return over several weeks. In addition, the opposite vocal cord may adapt over time, coming across the midline to improve voice and prevent aspiration. However, function will not be restored in the case of complete division. If a nerve becomes paralyzed in a medial position, it may serve as an obstruction to airflow but aspiration is less likely. If it becomes paralyzed in a lateral position, it will not obstruct airflow, but voice will be weak and coughing difficult. Further, with a cord in the lateral position, aspiration is more likely.

Injury to both recurrent laryngeal nerves usually creates an airway emergency, with the patient being unable to spontaneously ventilate adequately after extubation. This will require urgent placement of a tracheostomy if one has not been placed prophylactically after TR. It will also typically cause severe aspiration difficulties requiring the establishment of long-term enteral feeding.

Out of a total of 521 TRs for postintubation stenosis reported by the MGH group since 1986, 25 patients (5%) had varying degrees of postoperative laryngeal dysfunc tion.¹^–³ This included 62 patients who required complete resection of the anterior cricoid (higher than a “simple” TR). The laryngeal dysfunction was considered minor or temporary in 14, but 11 patients had more severe dysfunction. Of these, 7 required tracheostomy (3 permanent), 1 required a permanent T-tube, and 1 required a subglottic stent. Two patients required tube feedings for persistent aspiration.

TRs for tumors of the upper trachea, as one might expect given the greater extent of lateral dissection often required to allow complete tumor excision, likely lead to a greater incidence of recurrent nerve injury and laryngeal dysfunction. The MGH group reported 26 cervical TRs for tumor in a series of 126 primary tracheal tumors reported in 1990.⁴ Among the 126, 11 (8.7%) suffered vocal cord paralysis. Six (4.7%) suffered aspiration. Because this number includes patients who underwent more extensive resections and even carinal resections, the incidences of these complications after simple cervical TR for tumor are difficult to glean, but I believe it is fair to say that resections for tumor have a higher rate of nerve injury than those for postintubation lesions.

Grade 2–4 complication