The trachea originates below the cricoid cartilage and extends from front to back to the carina, which is located at about the level of the fourth thoracic vertebra. At that point, the trachea bifurcates into the right and left mainstem bronchi. The right main bronchus is in direct line with the trachea, and its length from carina to upper lobe takeoff varies between 1.5 and 2.0 cm. Distal to the right upper lobe bronchus, the primary bronchus becomes the bronchus intermedius, which is about 2 cm long.

The middle lobe bronchus arises from the anterior surface of the bronchus intermedius, almost in direct line with the origin of the superior segmental bronchus of the lower lobe, which arises from the posterior wall of the bronchus intermedius.

The left main bronchus arises from the carina at a more oblique angle than the right main bronchus. It is 4 to 6 cm long and passes under the aortic arch to lie posteriorly in the left hilum. It then bifurcates to form the upper and lower lobe bronchi. The lower lobe bronchus gives off its first segmental bronchus, the superior segmental bronchus, posteriorly 0.5 cm from the left upper lobe orifice. The distal bronchial section after left upper lobe sleeve resection is often dictated by the level of the orifice of the bronchus to the apical segment of the left lower lobe because of the absence of bronchus intermedius.

Care must be taken to preserve the left recurrent laryngeal nerve during bronchoplasties involving the proximal left main bronchus. The left recurrent laryngeal nerve originates close to the ligamentum arteriosum, where it courses from front to back around the aorta before ascending in the neck in the tracheoesophageal groove.

Bronchial arteries mostly arise separately from the anterolateral aspect of the descending thoracic aorta or from intercostal arteries located within 2 to 3 cm distal to the left subclavian artery. Most commonly, there are three bronchial arteries, two on the left side and one on the right side. Therefore, the right main bronchus is more susceptible to ischemia than its left counterpart.

The bronchial arteries circulate posteriorly to the airway, where they lie on the membranous portion of mainstem bronchi and where they eventually divide to supply lobar and segmental bronchi. On the right side, the single bronchial artery runs parallel to the azygos vein, by which it is overlapped. Another important feature of the bronchial circulation system is the rich anastomotic network interconnecting it with the pulmonary arterial circulation. This network is significant at the level of the lobar or segmental bronchi, and the pulmonary circulation may account for up to 75% to 90% of the airway blood supply.

Most of the venous drainage from the bronchial arterial system empties into the pulmonary veins; the rest empties into the bronchial veins located around the segmental and subsegmental bronchi. These bronchial veins subsequently empty into the azygos and hemiazygos systems.

The main PA originates in the pericardial sac from the right ventricle, and its axis is oriented in an anteroposterior direction, slightly upward and to the left. Below the aortic arch, it bifurcates into the right and the left branches.

The right PA runs horizontally to the right, behind the ascending aorta and the superior vena cava (SVC) and in front of the carina. Lateral to the SVC, the right PA lies in front of the right main bronchus, and it almost immediately gives rise to its first branch, to the right upper lobe. Shortly thereafter, the vessel curves inferiorly between the bronchus intermedius posteriorly and superior pulmonary vein anteriorly. Subsequently, the interlobar PA turns posteriorly behind the origin of the middle lobe bronchus. In this portion, one or two ascending arteries originate posterior to the segment of the upper lobe and the middle lobe artery. The middle lobe artery arises from the anteromedial surface of the interlobar artery, and the ascending arteries originate posteromedially at a slightly lower level. Distal to the latter is the origin of the artery to the apical segment of the lower lobe, and, subsequently, the PA branches into the arteries to the basal pyramid.

The left PA is shorter than its right counterpart; at its origin is the ligamentum arteriosum, and its relationship with the aortic arch continues posteriorly. Because the left PA curves around 60% to 75% of the circumference of the origin of the upper lobe bronchus, left upper lobe sleeve resection combined with resection of the PA is the most common type of bronchovasculoplasty. In fact, the PA abuts the superior, posterior, and inferior aspects of the upper lobe bronchus, leaving its anterior surface in contact with the superior pulmonary vein. The first branches, the apical and the anterior segmental arteries, arise anteriorly and superiorly to the upper lobe bronchus and posteriorly and superiorly to the superior pulmonary vein. Throughout its course around the upper lobe bronchus, the interlobar PA delivers branches to the upper lobe that are highly variable in number and location and are usually surrounded by lymph nodes. The most distal of these branches is the lingular artery, which usually arises distally or at approximately the same level as the artery that leads to the superior segment of the lower lobe. The lingular artery arises from the anteromedial surface of the interlobar PA, and the superior segmental artery originates posterolaterally. The PA axis is then oriented anteriorly, and the vessel branches into the arteries to the basal segments.

The term sleeve lobectomy refers to resection of a circumferential sleeve of mainstem bronchus contiguous with a pulmonary lobe, whereas bronchial sleeve resection is used to describe excision of the airway with sparing of parenchyma. At first conceived for patients unable to tolerate pneumonectomy, sleeve lobectomy has rapidly become an option for patients suitable for the more radical procedure. The former group of patients has been termed compromised, whereas the latter group with adequate cardiopulmonary reserve is named deliberate or elective. Bronchoplastic procedures have been reported being performed on 3% to 13% of the patients diagnosed with a resectable pulmonary malignant tumor. It is important to point out that this increased rate of sleeve lobectomy is achieved at the expense of a decreased incidence of pneumonectomy and not of lobectomy while the oncologic results remain unchanged. The indication for a sleeve resection for lung cancer is well established ( Table 8-1 ): a tumor arising at the origin of a lobar bronchus precluding simple lobectomy but not infiltrating as far as to require pneumonectomy. As a general rule, all lobes and even segments of the lung on occasion may be involved with tumors that are amenable to some form of lung-sparing bronchoplastic procedure. Oncologically, the primary goal of surgery is complete resection of lung cancer with adequate resection margins free of tumor. This is all the more true for carcinoid tumors or benign lesions. Evidence has been obtained that there is little, if any, gain in extending the resection as far as pneumonectomy. These considerations apply also to patients with nodal involvement limited to hilar lymph nodes (N1). Reconstructive surgery of the PA has exactly the same indications.

When considering surgical options and prognosis, it is useful to distinguish four anatomic situations in two groups of patients. The first and classic anatomic situation is a tumor found on bronchoscopy to arise in a lobar bronchus so as to preclude standard lobectomy. The second situation is where a carcinoma extrinsic to the airway may extend to the lobar bronchus. In the third situation, the bronchial margin may be found on frozen section to contain tumor. Finally, the fourth is where a lymph node with metastasis may adhere to the confluence of lobar and main bronchus and thus dictate resection of a sleeve of airway. Conversely, a metastatic node without adherence to the bronchus is not currently considered an indication for sleeve lobectomy.

The success of elective sleeve lobectomy and the prognosis of the individual patient seem to depend greatly on the intraoperative diligence of the surgeon in assessing the extent of disease.

A variety of benign or low-grade malignant tumors of the airway may necessitate sleeve lobectomy by their location within the airway.

Inflammatory strictures requiring resection of the lung and adjacent main bronchus are rare and are almost always caused by TB. Resection cannot be recommended in the presence of active TB or when active disease remains after resection. Bronchial disruptions rarely require sleeve lobectomy.

Besides all the above indications, we also consider sleeve lobectomy for patients who have pulmonary hypertension demonstrated by either echocardiography or right-sided heart catheterization. Sleeve lobectomy may also be performed for patients who have bronchial complications following lung surgery. In fact, “re-sleeve resection” for stenosis after sleeve right upper lobectomy has been reported.

Patients must be screened from a medical standpoint to be certain that they can tolerate thoracotomy.

Physical examination, chest radiography, spirometry, arterial blood gases, and quantitative ventilation and perfusion scans are performed routinely to evaluate functional status. Patients at high risk for heart disease are screened by echocardiography, thallium stress testing, and, in some cases, selective coronary arteriography. Tumor spread to the airway may be evaluated by fiberoptic bronchoscopy, which plays a key role in selecting patients for sleeve lobectomy; patients who have submucosal invasion or extrinsic compression of a lobar orifice with a positive elective biopsy are good candidates for sleeve lobectomy. Mediastinal nodal status is investigated by computed tomography (CT) or positron emission tomography (PET) scan. In patients with non–small cell lung cancer (NSCLC), mediastinoscopy is usually performed when CT shows mediastinal nodes larger than 1.0 cm in diameter or when PET-CT scan shows mediastinal fixation; mediastinoscopy is not used in patients with carcinoid tumor. Investigations for extrathoracic metastases are performed routinely. The need for resection of the PA in carcinomas of the upper lobes is usually established at the time of thoracotomy; however, a pulmonary angiogram may be performed when the tumor is adherent to the main PA in a patient whose preoperative functional test results contraindicate pneumonectomy. In patients at high risk, a right-sided heart catheterization is performed before and after balloon occlusion of the relevant PA to detect pulmonary hypertension, precluding pneumonectomy.

For patients who have tuberculous bronchostenosis, bronchoscopy is important to rule out active disease before a decision is made to perform resection. TB drug therapy is recommended for at least 6 months before resection, even when stenosis is thought to be due to TB.