Mediastinal Tracheostomy

Transcription

1 Mediastinal Tracheostomy Mario N. Gomes, M.D., Stephen Kroll, M.D., and Scott L. Spear, M.D. ABSTRACT Upper airway obstruction in primary or recurrent carcinomas of the head and neck extending into the mediastinum may demand surgical intervention despite severe technical difficulties in patients with tumors previously considered inoperable. In fact, many of these tumors may be operable and some perhaps curable. A technique has been developed based in part on our experience with previously described procedures. A preliminary sternal split is used to demonstrate the extent of the mediastinal involvement as well as to provide enhanced exposure and proximal control of the great vessels. The pectoralis major muscle is used with a generous flap of overlying skin comprising nearly half of the anterior portion of the chest. A tracheostomy is then created in a fashion similar to the placement of a cardiac valvular prosthesis by creating a circular defect in the pectoralis major flap and suturing it to the tracheal remnant. This technique offers a reasonably safe and reliable means of creating a low anterior mediastinal tracheostomy for tumors previously considered inoperable. The preliminary sternal split makes the procedure safer and easier to perform, and the use of a very large pectoralis major island flap allows for reliable closure of the resulting mediastinal and sternal defects. Advanced carcinoma of the lower neck with direct extension to the superior mediastinum poses a major therapeutic challenge. This is particularly true of cervicothoracic tumors of laryngeal, tracheal, esophageal, or thyroid origin. Although the opportunity for cure in such cases is remote, upper airway obstruction may force surgical intervention as a palliative measure in patients previously considered inoperable. The location of these tumors at the thoracic inlet is a traditional no man s land because of the vital structures lying posterior to the manubrium and clavicles. Removal of recurrent tracheal stoma1 tumors with simultaneous anterior mediastinal tracheostomy was initially associated with high morbidity and mortality, generally secondary to mediastinal infection and rupture of the innominate artery [l]. Subsequent techniques for mediastinal tracheal reconstruction have met with mixed success [2-61. One of the From the Divisions of Thoracic and Cardiovascular Surgery and Plastic and Reconstructive Surgery, Georgetown University Medical Center, Washington, DC. Accepted for publication Aug 25, Address reprint requests to Dr. Comes, Department of Surgery, Georgetown University Medical Center, 3800 Reservoir Rd, NW, Washington, DC most promising of these includes transmediastinal resection of a cervicothoracic esophageal tumor with mediastinal tracheostomy using a pectoralis major musculocutaneous flap. Recently, we have further modified this procedure to make it easier and safer to perform. Patients and Methods Two patients were referred to Georgetown University Medical Center from other institutions. Both had endotracheal tubes in place following progressive respiratory difficulty and respiratory arrest. Limited neck explorations had been performed in both patients, and the diagnosis of unresectable malignancy had been established. Patient I A 60-year-old man with an enlarging neck mass of three weeks duration was admitted to another hospital. Two days after admission progressive upper airway obstruction developed, followed by respiratory arrest, which required emergency endotracheal intubation. After two unsuccessful attempts at extubation, a limited surgical exploration of the neck was performed; this revealed a large, firm, nonresectable mass intimately adherent to the trachea. The tumor and a tracheal mass seen at endoscopy were originally reported as leiomyosarcoma. Five days later the patient was referred to Georgetown University Medical Center with a solid tumor mass (8 cm x 6 cm) in the anterior portion of the neck in the area of the thyroid gland. After another failed attempt at extubation, endoscopy showed paralysis of the left vocal cord and a fungating mass at the right anterolateral wall of the trachea. The canna and the proximal 3 cm of the trachea appeared free of disease. At operation the anterior trachea below the cricoid cartilage was found to be eroded by the tumor, and the endotracheal tube was easily seen through the large opening. The tracheal mass was resected en bloc with the thyroid and the larynx, leaving a tracheal stump 3 cm long. The final histologic diagnosis was malignant fibrous histiocytoma involving the thyroid gland, trachea, lower larynx, and peritracheal soft tissue, possibly tracheal in origin. Patient 2 A 79-year-old man experienced rapidly spreading bilateral cervical lymphadenopathies leading to respiratory arrest and requiring emergency intubation and resuscitation. An attempt at tracheostomy was unsuccessful. A biopsied cervical lymph node was interpreted as poorly differentiated squamous cell carcinoma of unknown Origin. The patient was transferred to Georgetown University Medical Center with an endotracheal tube in place. A computed tomographic scan showed a large neck mass 539 Ann Thorac Surg 43: , May 1987

2 540 The Annals of Thoracic Surgery Vol 43 No 5 May 1987 extending into the upper anterior mediastinum. Triple endoscopy failed to demonstrate any mucosa abnormalities. En bloc resection, including thyroid, larynx, upper trachea, and peritracheal lymph nodes, was performed in continuity with a standard radical dissection of the right side of the neck and a partial dissection of the left side. The final histologic diagnosis was carcinoma of the thyroid gland with follicular, papillary, squamous, and undifferentiated patterns. Operative Procedure Construction of a mediastinal tracheostomy begins with a longitudinal sternal split performed in standard fashion. After the median sternotomy is accomplished, the surgeon can safely excise the two halves of the manubrium as well as proximal portions of the first two ribs and medial clavicular heads. Excellent access to the superior mediastinum is thus obtained (Fig 1).The mediastinum is explored and tumor resectability is determined based on the degree of invasion of the great vessels and prevertebral fascia; the available length of tumor-free distal trachea is also noted. Dissection is initiated distally to include low periesophageal and pentracheal lymph nodes as well as adjacent mediastinal fat Fig I. lntraoperative mediastinal exposure after sternal split and excision of the manubrium but before tumor resection. (SVC = superior uena cava; LIV = left innominate vein.) and thymus. The dissection may include portions of one or both sides of the neck, including lymph nodes at the jugular or jugulosubclavian vein junction. All major vessels are easily visualized and accessible throughout the procedure. The distal trachea is mobilized only as much as necessary to avoid devascularization. It is obliquely transected at the appropriate level, leaving a longer flap posteriorly. The distal tracheal stump is then intubated with a sterile (cuffed) endotracheal tube that is passed under the drapes to the anesthetist. The remainder of the dissection, including primary tumor, trachea, larynx, thyroid, and cervical nodes may then be completed. The divided distal sternum is then reapproximated. Although we have not found it necessary to divide either innominate vein, ligation of the left innominate vein at its origin would facilitate exposure of the lower trachea. It is imperative, however, that one innominate vein be left intact. After the resection, a sizable filling defect is left at the base of the neck and anterior mediastinum with exposure of the carotid and innominate arteries (Fig 2). Re- Fig 2. The tumor mass including the l a y n x has been excised. A sterile endotracheal tube is placed into the tracheal stoma. The large arterial and venous vessels are exposed and easily accessible. Note the proximity of the tracheal stump and the innominate a r t e y (IA). (RCA = right carotid artery; LCA = left carotid a r t e y ; SVC = superior vena cava.)

3 541 Comes, Kroll, Spear: Mediastinal Tracheostomy Fig 3. A large pectoralis major musculocutaneous flap including the most of one anterior portion of the chest and extending to the midline medially and near the costal margin inferiorly. (TAV = thoracoacromial vessels; SCA = subclavian artery.) construction is accomplished with a large pectoralis major musculocutaneous flap, although any large robust flap may be used. The important principle is the creation of a flap large enough to close the entire defect without tension and still allow a tracheostomy deep within the mediastinum. Nearly the entire pectoralis major muscle is used as a flap along with a skin paddle (15 x 20 cm), which represents most of the skin of the anterior half of the chest (Fig 3). A true musculocutaneous island, attached only by the neurovascular bundle, is created by dividing the tendinous and clavicular portions of the pectoralis major muscle. This provides maximal mobility without compromising the circulation, which is maintained by the dominant pedicle, the thoracoacromial vessels. Undermining and advancing the medial and lateral edges of the wound will help close the donor defect, but another flap or split-thickness skin graft will be required to complete closure of the donor site. A site for the proposed tracheal stoma is chosen somewhere in the middle of the flap. A circular defect is created by excision of skin, fat, and muscle, avoiding the major vessels on the deep surface of the muscle. There is no need to displace the trachea inferior to the innominate artery because the flap will reach down to the trachea even if it is beneath that vessel. In a manner similar to the replacement of an aortic valve, all of the interrupted sutures are first placed through the full thickness of the tracheal rim, and then brought through the opening of the flap for an additional bite of the flap skin edges. After all sutures are in place, the endotracheal tube is repositioned through the opening of the flap, and the flap is lowered with the Fig 4. Eight interrupted sutures have been placed around the circumference of the transected trachea and through the aperture created in the pectoralis flap. The endotracheal tube is then repositioned through the pectoralis flap and the sutures are tied, bringing the flap into the mediastinurn and creating a new stoma. Fig 5. Sagittal vim of the funnel effect of the flap in the mediastinuin with protection of the great vessels and a secure, tension-free tracheal stoma. sutures tied sequentially. Precise apposition of the skin and the tracheal mucosa is imperative (Figs 4, 5). The tracheal stoma remains the most superior structure in the mediastinum, and the great vessels and mediastinum are protected by a two-layer (skin and muscle) seal around the tracheal stoma. Results Although both of our patients required ventilatory support for 48 to 72 hours, pulmonary function and blood gas determinations were normal after extubation.

4 542 The Annals of Thoracic Surgery Vol 43 No 5 May 1987 Neither patient demonstrated a flail chest or other compromise of pulmonary function. A small pharyngeal fistula developed in Patient 1, but it healed without progressing to mediastinitis after two weeks of intravenous alimentation. Postoperatively the patient received radiation therapy to the neck and mediastinum and remained free of disease for five months until a stomal recurrence appeared requiring further radiation. He was alive without stomal difficulties or further tumor recurrence nine months later. The second patient healed uneventfully in spite of his advanced age, and there were no major complications. However, one month postoperatively he died suddenly as a result of an acute, massive myocardial infarction. Comment Cure or long-term control of advanced or recurrent carcinoma of the lower neck can be accomplished with extensive radical surgery including relocation of the trachea to the anterior chest wall. Such methods may apply to reconstruction of tracheal stenosis or stomal recurrence, primary cai;cinoma of the subglottic area, trachea, and larynx, extensive thyroid carcinoma, and carcinoma of the cervicothoracic esophagus. Although extended laryngotracheal resection may appear contraindicated by the extent or type of lesion, palliative intervention may still be desirable for patients with obstructing mediastinal lesions and progressive respiratory distress that requires endotracheal intubation. The location of these tumors at the thoracic inlet and extending into the anterior mediastinum is traditionally a "no man's land." These patients may be seen by head and neck, plastic, general, or thoracic surgeons, none of whom is likely to be completely familiar or comfortable with all of the techniques necessary for its correction. Patients with massive tumor in this region with extension posterior to the manubrium and clavicles should be given the benefits of a team approach. With the cervical lymphatics draining into the mediastinum, a wide, in continuity resection that includes primary tumor and mediastinal metastases is appropriate when there is palpable tumor extending beneath the manubrium and clavicle. The presence of vital structures in the intended surgical field makes this procedure potentially dangerous and requires adequate preliminary exposure of the upper mediastinal structures in jeopardy. Removal of the manubrium, medial clavicular heads, and the proximal first two costal cartilages permits access to the superior mediastinum that is not possible with either a cervical or thoracic approach alone. Excellent exposure is thus afforded to the entire intrathoracic trachea and cervicothoracic esophagus. Although removal of the upper sternum was recorded by Bardenheuer in 1885 (71, it was not until 1962 that Sisson and associates [l] reported their results of onestage radical resection of recurrent postlaryngectomy stomal carcinoma with simultaneous creation of a mediastinal tracheostomy. Only 5 of their 16 patients survived the immediate postoperative period [8]. The deaths resulted from mediastinitis secondary to separation or necrosis of the flaps. The bipedicled upper thoracic apron flap as described by Grillo [3] in 1966 provided minimal tension at the tracheostomy site but was not satisfactory to resurface large defects of the anterior portion of the neck. A thoracoacromial ("nipple") flap, as described by Conley and others [2, 4, 51, provided a large surface area for creation of the tracheal stoma and resurfacing the lower neck, but this flap had limited mobility. Ariyan [9] and Withers and colleagues [lo] have successfully used the pectoralis major musculocutaneous flap for head and neck reconstruction even in patients who have undergone preoperative radiation therapy. These compound flaps have excellent vascularity, provide bulk to obliterate dead space, and have remarkable reach without the need of staged procedures. The versatility of the pectoralis major flap [ll, 121 arises from the proximal location of its dominant blood supply (the thoracoacromial artery), which is a branch of the subclavian artery. In an earlier procedure, a mediastinal tracheostomy was created with a pectoralis major flap that had been previously split to facilitate suturing [6]. A review of all previously described techniques reveals shortcomings in each. First, en bloc removal of the manubrium and medial segments of the adjacent ribs and clavicles without a preliminary sternotomy is hazardous because of a failure to gain control of the great vessels. In our earlier experiences, injury to the innominate vein with massive bleeding occurred after transection of the clavicle, and blood loss continued until sufficient bone was removed to allow vein repair under direct vision. Second, aggressive skin resection at the base of the neck, essential for adequate margins and reliable healing, requires a very large flap to close the neck defect and still reach deep into the mediastinum for a tension-free tracheostomy. Previously described flaps are too small, too unreliable, or too immobile to succeed; splitting the flap simply is unnecessary. Our method refines other techniques and makes the procedure simpler and safer. Performing a standard sternal split from below before resecting the manubrium is not only faster but safer. With this accomplished, the surgeon can quickly and safely excise overlying bone and allow exploration of the anterior mediastinum. After exploration, if resection is planned, dissection of innominate veins and the other vascular structures can proceed with relative ease and safety. This approach allows for easy tracing of the great vessels from the heart to the base of the skull with complete visualization of all structures at all times. Proximal control is also available in case of injury to major arteries or veins. Because of the potential loss of support of the anterior chest wall, limited resection of only the two first costal cartilages is advised, particularly because access to the anterior mediastinum and canna is easily provided by resection of these along with manubrium and medial clavicles. The cervical dissection can be modified to excise scars, tracheostomy stomas, sinus tracts, recurrent tumor, or metastatic nodes.

5 543 Gomes, Kroll, Spear: Mediastinal Tracheostomy An extremely generous musculocutaneous flap (pectoralis major, latissimus dorsi, or other) allows for wide excision of compromised neck skin yet provides adequate tissue to create a large, viable funnel attached superficially at the neck and reaching deep into the chest for coaptation to the tracheal remnant. In salvage cases such as these, the donor site morbidity required for such a large flap should not deter one from doing what is necessary for success. A skin graft or second flap will likely be needed for donor site closure. A median sternotomy combined with a large musculocutaneous flap allows for safe, fast, and effective exploration of the mediastinum and mediastinal tracheostomy. Although this procedure could be performed by a single well-trained surgeon, it is greatly facilitated by a team approach with surgeons of several cooperating specialties. Although our experience with this method has been limited to two patients, we are impressed with its clear practical advantages in creating a low mediastinal tracheostomy in patients previously considered to have inoperable tumors. References 1. Sisson GA, Straehley CJ: Mediastinal dissection for recurrent cancer after laryngectomy or radical surgery. Laryngoscopy 72:1064, Conley JJ: The use of regional flaps in head and neck surgery. Ann Otol Rhino1 Laryngol 69:1223, Grill0 HC: Terminal or mural tracheostomy in the anterior mediastinum. J Thorac Cardiovasc Surg 51:422, Sisson GA, Bytell DE, Becker SP: Mediastinal dissections- 1976: indications and newer techniques. Laryngoscope 87:751, Orringer MB, Sloan H: Anterior mediastinal tracheostomy: indications, techniques, and clinical experience. J Thorac Cardiovasc Surg , Withers EH, Davis JL, Lynch JB: Anterior mediastinal tracheostomy with a pectoralis major musculocutaneous flap. Plast Reconstruct Surg 67:381, Bardenheuer: Die Resection des Manubrium sterni. Dtsch Med Woschenschr 11:688, Sisson GA, Edison BD, Bytell DE: Transsternal radical neck dissection: postoperative complications and management. Arch Otolaryngol 101:%, Ariyan S: The pectoralis major myocutaneous flap: a versatile flap for reconstruction in the head and neck. Plast & Reconstruct Surg 63:73, Withers EH, Franklin JD, Madden JJ, Lynch JB: Pectoralis major musculocutaneous flap: a new flap in head and neck reconstruction. Am J Surg 138:537, Sisson GA, Goldman ME: Pectoral myocutaneous island flsp for reconstruction for stoma1 recurrence. Arch Otolaryngol , Arnold PG, Pairolero PC: Use of pectoralis major muscle flaps to repair defects of anterior chest wall. Plast Reconstruct Surg 63:205, 1979