COPD - Lung Volume Reduction Surgery (LVRS) Prof. Khaled KARARA Prof. of Department of Cardiothoracic Surgery Alexandria Faculty of Medicine

Emphysema Emphysema, along with chronic bronchitis, together are referred to as Chronic Obstructive Lung Disease (COPD). Characterized by increase beyond normal in the size of air spaces distal to the terminal bronchiole containing alveoli, Destructive changes in their walls and reduction in their number "Heterogeneous" and "homogenous“ Heterogeneous is when emphysema is more isolated to certain areas of the lungs and the extent of emphysema varies between segments of the lungs. Homogenous is when emphysema has a more diffuse pattern and it is distributed more evenly throughout the lungs

Morphological Types of Emphysema Centriacinar Begins in the respiratory bronchioles and spreads peripherally. Also termed centrilobular emphysema. Associated with long-standing cigarette smoking. Predominantly involves the upper half of the lungs. Panacinar Destroys the entire alveolus uniformly. Predominant in the lower half of the lungs. Generally observed in patients with homozygous alpha1-antitrypsin (AAT) deficiency. Paraseptal Preferentially involves the distal airway structures, alveolar ducts, and alveolar sacs Localized around the septae of the lungs or pleura Apical bullae may lead to spontaneous pneumothorax

Emphysema Clinical Manifestation Breathlessness on exertion Reduction of alveolar surface for gas exchange Collapse of smaller airways with trapping of alveolar gas in expiration Causes the chest to be held in the position of inspiration Prolonged expiration and increased residual volume

Possible Complications of Emphysema Pneumothorax Can be fatal in patients with severe emphysema because the respiratory reserve is limited. Pulmonary hypertension & Cor pulmonale Giant bullae Sometimes half the size of the lung Lungs have a much smaller surface area The bullae can become infected More likely to develop pneumothorax Recurring infections

Lung Volume Reduction Surgery Many people who suffer with emphysema have portions of the lung which are more affected than others (heterogenous). In lung volume reduction surgery (LVRS), a large area of damaged lung is removed to allow the remaining lung tissue to expand.

Lung Volume Reduction Surgery Good Candidates Who have severe emphysema that does not respond to optimum medical therapy. Who are younger than 75 to 80 years old. Who have not smoked for at least 4 months. Who have areas of the lung which can be removed to improve lung function (heterogenous). Chest X-ray, CT scan, and lung perfusion studies. Other medical conditions must be well controlled. Must be able to participate in a pulmonary rehabilitation program prior to and after surgery.

Lung Volume Reduction Surgery The National Emphysema Treatment Trial (NETT) Group 1: Patients with predominantly upper lobe emphysema and low exercise capacity Have improved survival and functional outcomes after LVRS compared to medical therapy. Group 2: Patients with predominantly upper lobe emphysema and high exercise capacity Have improved functional outcomes after LVRS but no difference in survival compared to medical therapy. Group 3: Patients with non-upper lobe emphysema and low exercise capacity Have improved survival after LVRS but no difference in survival compared to medical therapy.

Lung Volume Reduction Surgery Poor Candidates NETT reports that people not considered good candidates for this surgery include: Severely impaired lung function Patients with extremely poor pulmonary function (FEV1 20% or less than predicted). Uniform pattern of emphysema throughout the lungs on CT scan. Non-upper lung emphysema and high exercise capacity. Certain other serious medical problems.

Lung Volume Reduction Surgery Anticipated Benefits As overall hyperinflation decreases, diaphragm and chest wall mechanics would improve. Increase in elastic recoil thereby restoring the outward pull on bronchioles and increase expiratory flow Increase flow would decrease dynamic hyperinflation Improvement in ventilation and perfusion matching improves alveolar gas exchange which in turn may decrease need for supplemental oxygen.

Lung Volume Reduction Surgery

Linear cutter Staplers

Minimally invasive linear-cutter-staplers

Thoracoscopic linear-cutter-staplers (VATS)

Emphysematous Bullae

Potential Complications Intraoperative complications Postoperative complications Prolonged air leakage: most common complication. Pneumonia Reintubation Arrthymias Bleeding Death (3-8%up to 15 in more severe emphysema)

Bronchoscopic Lung Volume Reduction (BLVR) LVRS → postoperative morbidity → selection criteria that exclude many patients. Less-invasive bronchoscopic approaches to lung volume reduction have been developed to reproduce the effects of LVRS: Valves that allow unidirectional airflow in exhalation to collapse target lung lobe Biological lung volume reduction with biodegradable gel into bronchi Creation of airway bypass tracts (stents between cartilagenous bronchi with air traping and normal lobes). Coils Thermal vapor ablation

Rationale for BLVR Use of endoscopic methods to collapse of hyperinflation would have the beneficial effects similar to resecting these areas without the morbidity of surgery. Patients not a good surgical candidates might be able to undergo BLVR.

Bronchoscopic Lung Volume Reduction Bronchial Valves The intrabronchial valve (Spiration Inc., Redmond, WA, USA) has six struts made of nitinol covered by polyurethane membrane in the shape of an umbrella.

Bronchoscpic Lung Volume Reduction The Zephyr endobronchial valve (Pulmonx Inc., Palo Alto, CA, USA) is a one way valve that is mounted on a self-expanding nitinol stent. The endobronchial valve (EBV) allows unidirectional airflow mucus clearance in expiration and is available in various sizes.

BLVR, 7 Lessons Learned Arch Bronconeumol. 2012;48:221-2 1. Treatments with endobronchial valves are effective in heterogeneous emphysema if there is “complete lobar exclusion”, meaning there is no collateral communication with other pulmonary lobes or segments. 2. Endobronchial valves procedure is a reversible as they can be easily extracted if the patient's condition either worsens or does not improve (which is not possible with foam sealant, coils or vapor). 3. As they do not depend on pulmonary ventilation, neither foam sealant, nor coils nor vapor ablation requires complete lobar exclusion to be effective. 4. Foam sealant and vapor in particular can mask over lung cancer and should not be used in lobes with nodules, scarring or bronchial thickening. 5. Coils cause a very important mechanical retraction of the pulmonary parenchyma, and if there is a peripheral air leak it may be very difficult to resolve. 6. The patients who demonstrate the best response are those who have a higher degree of air trapping, with a residual volume higher than 225%. Patients with very severe COPD and diffusion below 20% or FEV1 lower than 20% should not be treated. 7. When the emphysema is very homogeneous on CT, valves cannot be used

Disadvantages No improvement & obstruction. Technical difficulties & Design defects. Better results in unilateral than bilateral applications and entire lobe than segments. Better to use LVRS with definite large bullae. Cost and availability. LVRS improves inspiratory capacity by improving inspiratory muscle function, whereas BLVR improves diaphragm function.

Complications Pneumothoax (most common). Pneumonia. Bronchospasm. Bronchial hypersecretion. Granulation tissues.