Lung Volume Reduction Surgery for Emphysema
2017-06-28T20:46:41Z (GMT) by
A 65-year-old patient was admitted to the author´s department to assess his inclusion in the lung transplantation program. The patient had a prior history of smoking (50-pack years) and emphysema (COPD GOLD IV). In the previous year, he had been treated with 2–4 lpm home oxygen, 24 hours a day. The patient commonly experienced severe dyspnea with daily routine activities and had some isolated exacerbation episodes in the previous three years.
The x-ray showed hyperinflation, and a CT scan confirmed extensive parenchymal destruction. The upper fields were most severely affected and the lower fields were moderately affected. The arterial blood gas (with oxygen 3 lpm) revealed: ph 7.37, pO2 106 mmHg, and pCO2 42.7 mmHg. The pulmonary function tests showed: FEV1 750 ml (31%), FVC 1710 ml (58%), DLCO 42%, TLC 7970 ml (155%), RV 5910 ml (274%), and RV/TLC 74%. In a six-minute walk test the patient walked 340 m with one stop. Initial and final saturations were 94% and 83%, respectively. Echocardiography was normal and right catheterization revealed a mean pressure of 13 mmHg. The perfusion scan revealed a right lung perfusion of 77% (upper 3.8%, middle 40.2%, lower 33%) and a left lung perfusion of 23% (upper 2.3%, middle 13.8%, lower 6.9%).
According to the NETT trial results, the patient was a good candidate for lung volume reduction surgery (LVRS). The possibility of lung transplantation was dismissed, and the authors planned a thoracoscopic LVRS.
The patient was placed in the supine position and three incisions were made in each side, beginning with the right side because of its better function. About 80% of the right upper lobe and 60% of the left upper lobe were excised by multiple applications of a stapler device buttressed with strips of Gore-Tex, which were attached to the surfaces of the stapler before its application. Biological glue was applied to further reinforce the stapler line. The pulmonary ligament was not divided. A single 36F chest tube was inserted in each side at the end of the procedure. For the first postoperative day, -10 cm H2O suction was applied. The chest tubes were then left on water seal because the lung remained expanded with minimal air leak. The right tube was removed after six days and the left after nine days. The patient was discharged on the tenth postoperative day. After one year, the patient had improved functionally and did not need oxygen. Dyspnea was 1/4 (mMRC). The one-year postoperative lung function test revealed: FEV1 1500 ml (66%), FVC 3190 ml (109%), TLC 105%, RV 103%, and DLCO 54%.
The NETT trial was published in 2003 (N Engl J Med 2003;348:2059–73). In this study, 1,218 patients were randomized to LVRS (680) or to medical therapy (538). The conclusion was that LVRS is a procedure that provides clinical and physiologic improvements in well-selected patients. In these patients, LVRS it is safe and effective because it improves survival, exercise capacity, and quality of life.
Initially, the reported 90-day mortality was 5.5%. Recently, Gingsburg et al. reported a 90-day mortality of 0% (Ann Thorac Surg 2011;91:1556-60). LVRS can delay the necessity for lung transplantation for several years. One issue is deciding between lung transplantation and LVRS in a patient who is nearing the age limit for lung transplantation. Weinstein et al. described a greater one-year improvement in BODE index, FEV1, and Borg dyspnea scale with lung transplantation, although costs were also higher and long-time survival was shorter (COPD 2007;4:15-22). In the author’s opinion, LVRS is preferable in these circumstances.
Unfortunately, despite the results of the NETT trial, LVRS is a procedure infrequently performed in most thoracic surgery units. There are most likely an important number of COPD patients that meet NETT criteria for LVRS, but are not offered this procedure. Quitting tobacco, home-oxygen therapy, NIMV during exacerbations, and LVRS are the only interventions that have been demonstrated to prolong survival in COPD patients. Bronchoscopic methods of lung volume reduction have demonstrated neither superior nor similar outcomes so far.