Surgical therapy for chronic obstructive pulmonary disease.
Review
Overview
abstract
Many patients with severe chronic obstructive pulmonary disease (COPD) experience incapacitating breathlessness and exercise limitation. Multiple surgical techniques have been utilized to achieve resection of giant, localized bullae with documented short-term benefit in pulmonary function and dyspnea in highly selected patients. The poorest long-term outcome has been noted in those with greater degrees of emphysema in the remaining lung, greater underlying chronic bronchitis, and a bulla occupying less than one third of the hemithorax, particularly if compressed normal lung is not evident. Lung volume reduction surgery (LVRS) in the absence of giant bullae has become more widely accepted in selected patients. Bilateral LVRS procedures appear to result in greater short-term improvement than unilateral LVRS, whereas physiological benefits appear similar with video-assisted thoracoscopy (VATS) or median sternotomy (MS) techniques. Improvement in dyspnea and health status after LVRS has been documented and appears to be better preserved over longer-term follow-up than physiological improvement. Clear direction has been provided in identifying optimal candidates for bilateral LVRS; patients with a postbronchodilator forced expiratory volume in 1 second (FEV (1)) < or = 20% predicted and a diffusing capacity for carbon monoxide (DL (CO)) < or = 20% predicted or homogeneous emphysema exhibit a much higher mortality with LVRS than with medical management. Patients with upper-lobe predominant emphysema and a low postrehabilitation exercise tolerance exhibited a decreased risk of mortality after LVRS. Patients with non-upper lobe predominant emphysema on high-resolution computed tomography (HRCT) and a high postrehabilitation exercise capacity exhibit an increased risk of death after LVRS. Patients with upper lobe predominant emphysema and a high postrehabilitation exercise capacity or patients with non-upper lobe predominant emphysema and a low postrehabilitation exercise capacity do not have a survival advantage or disadvantage, whereas those with upper lobe predominant emphysema treated surgically are more likely to improve their exercise capacity after surgery. Lung transplantation is an option for a more limited number of patients. Consistent short-term spirometric improvement after both single- and double-lung transplant has been documented. Long-term results of lung transplantation are limited by significant complications that impair survival; an approximately 80% 1-year, 50% 5-year, and 35% 10-year survival has been reported. Bronchiolitis obliterans is the most important long-term complication of lung transplantation resulting in decreased pulmonary function. In general, a COPD patient can be considered an appropriate candidate for transplantation when the FEV (1) is below 25% predicted and/or the paCO (2) is > or = 55 mm Hg.