Rigid Bronchoscopy with Y Stent Insertion at Left Secondary Carina

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Chapter 24 Rigid Bronchoscopy with Y Stent Insertion at Left Secondary Carina

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This chapter emphasizes the following elements of the Four Box Approach: risk-benefit analysis and therapeutic alternatives, techniques and instrumentation, and referrals to medical, surgical, or palliative/end-of-life subspecialty care.

Case Description

A 75-year-old man with a 120–pack-year history of smoking and COPD (FEV1 52% predicted, DLCO 39% predicted) developed progressive dyspnea, a weak and hoarse voice, and hemoptysis. His usual exertional dyspnea had progressed to the point that he now required assistance with activities of daily living. Chest CT showed a 6 × 5 × 7 cm left infrahilar mass involving the distal left main bronchus (LMB) and the entrance to the left upper and lower lobe bronchi (Figure 24-1, A and B). In addition, mediastinal lymphadenopathy was significant in stations 7 (subcarinal) and 4 L (left lower paratracheal). Flexible bronchoscopy showed an immobile left vocal cord and near complete obstruction in the distal LMB characterized by extrinsic compression and exophytic endoluminal tumor with hypervascular mucosa (Figure 24-1, C). Examination of the airways distal to the tumor was possible using forced saline lavage and showed patent distal segments but significant involvement of the left secondary carina (LC2). Rigid bronchoscopy was performed under general anesthesia with spontaneous assisted ventilation. Endobronchial needle aspiration (EBNA) with rapid on-site evaluation (ROSE) revealed non–small cell lung cancer (NSCLC). Nd:YAG laser photocoagulation and bronchoscopic debulking partially restored patency to left upper and lower lobe bronchi. However, tumor infiltration, cartilaginous collapse, and extrinsic compression required insertion of a large Y silicone stent (16 mm diameter tracheal limb, 12 mm bronchial limbs) placed within the left main bronchus (Figure 24-1, D and E).

Case Resolution

Initial Evaluations

Physical Examination, Complementary Tests, and Functional Status Assessment

This patient required considerable assistance at home. His functional impairment was consistent with a Karnofsky Performance Scale score (KPS) of 50. At the time of hospitalization, however, KPS was only 20 (severely disabled, where hospitalization was necessary but death was not imminent).1 His Eastern Cooperative Oncology Group (ECOG) performance scale, which may be a better predictor of prognosis than KPS,2,3 was 3 (i.e., the patient was capable of only limited self-care and was confined to bed or chair for more than 50% of waking hours). Assessment of this patient’s performance status is essential for guiding therapeutic interventions because this degree of impairment, due to lung cancer or comorbid conditions (e.g., chronic obstructive pulmonary disease [COPD]), may preclude resection or, alternatively, chemoradiotherapy.4 In fact, this patient was not operable based on his pulmonary function tests and functional status. Relevant to his case, however, is that the combination of interventional bronchoscopy and external beam radiation therapy (EBRT) might improve survival, symptoms, and quality of life, as has been previously shown in patients with lung cancer, central airway obstruction, and KPS less than 50.

The patient’s weak voice and hoarseness are explained by unilateral (left) vocal cord immobility as noted on bronchoscopy (see video on ExpertConsult.com) (Video V.24.1image). This was likely due to unilateral recurrent laryngeal nerve (RLN) injury, which caused the affected vocal fold to rest in the paramedian position. The contralateral vocal fold may or may not provide adequate glottic closure during phonation. If closure is not achieved, the residual glottal gap results in air escape with a weak voice secondary to a “leaky valve” phenomenon.5 In unilateral RLN injury, the glottic aperture is usually adequate, and related dyspnea and stridor are rare. Glottal incompetence, however, increases the risk for aspiration, particularly with thin liquids. Cough, which requires transient tight glottic closure, may also be affected; this is important in cases of airway stent insertion with risk for mucus plugging and difficulty raising secretions. Associated sensory loss from RLN involvement may also cause dysphagia, a symptom not seen in our patient. With regard to staging, RLN involvement is consistent with T4 disease. In conjunction with N2 disease on computed tomography (CT) scan (involvement of stations 7 and 4 L), this patient’s clinical stage is at least IIIB, and estimated median survival time is 10 months and 5 years for 7% despite multimodality treatment.6

Procedural Strategies

Indications

This patient required tissue diagnosis. We elected to proceed with rigid bronchoscopy under general anesthesia to restore airway patency with laser and silicone stent insertion and to diagnose the airway lesion using endobronchial biopsy, bronchial washing, and/or endobronchial needle aspiration. Chemoradiotherapy currently constitutes the standard of care for patients with inoperable locally advanced non–small cell lung cancer (NSCLC).10 This treatment, however, is usually restricted to patients who maintain a good performance status.11

Central airway obstruction (CAO) in the setting of NSCLC is associated with a very poor prognosis. In one study, median and 1 year survival of patients with malignant CAO were reportedly as low as 3.4 months and 15%, respectively.12 However, patients with advanced NSCLC with locally treated CAO combined with systemic chemotherapy might have survival rates similar to those patients without CAO treated with chemotherapy alone.13 Interventional bronchoscopic procedures in this patient with inoperable disease are expected to restore airway patency and improve lung function, dyspnea, and functional status, thus allowing initiation of systemic therapy, which could improve his survival.14

Expected Results

For diagnosis, endobronchial needle aspiration (EBNA) with rapid on-site evaluation (ROSE) was performed. In patients with visible endobronchial lesions such as this, the diagnostic yield increases from 76% with conventional procedures alone to 96% with EBNA in addition to conventional procedures (washings, brushings, and biopsy).16

For restoring airway patency in our patient with near complete obstruction in the distal left main bronchus (LMB), left secondary carina (LC2) involvement, and a mixed pattern of obstruction (extrinsic and endoluminal exophytic), a straight metal or silicone stent would not have restored patency to the obstructed lobar bronchi. Therefore we decided to insert a silicone Y stent. This type of stent can be used for patients with fixed or dynamic CAO from benign or malignant disease, but the most common uses are to restore airway patency, to improve dyspnea and quality of life for patients with malignant CAO involving the mainstem bronchi and the lower trachea (Figure 24-2), and to reduce recurrent infection in patients with tracheoesophageal or bronchoesophageal fistulas.1720 Y stents are also effective in restoring airway patency, and they improve symptoms in patients with severe diffuse tracheobronchomalacia, but with a high rate of nonfatal complications.21,22 In our patient, a Y silicone stent insertion was planned to restore and maintain LMB and left upper lobe (LUL) and left lower lobe (LLL) airway patency, which would allow the following:

Risk-Benefit Analysis

For diagnosis, we chose to perform EBNA before proceeding with laser photocoagulation. In our experience, EBNA has a lower risk of bleeding and provides immediate diagnosis when ROSE is available. In contrast with endobronchial biopsy, however, tissue architecture is not seen.16 With regard to restoring airway patency, the risks of further physiologic compromise and massive bleeding were considered to be outweighed by the benefit of restoring airway patency, the ability to diagnose the lesion, and improved functional status and the offer of systemic therapy. Alternatives to our approach should be considered on a case-by-case basis.