Effect of lung volume reduction surgery for severe emphysema on right ventricular function

Lung volume reduction surgery (LVRS) can improve the functional capacity of selected patients with severe emphysema. Hypothesized physiologic effects of LVRS include an improvement in right ventricular function, although this has not been investigated in detail. To help clarify this issue, we used fast-thermistor thermodilution at rest and during submaximal upright exercise in 12 patients, before and 6 mo after bilateral LVRS. Preoperatively, all patients had severe airflow obstruction, with a mean FEV(1) of 0.69 L and an RV-to-TLC ratio of 0.67. Six months after LVRS, significant improvements occurred in respiratory function measures (+0.39 L in FEV(1), p < 0.002; and +/- 0.15 in RV/TLC ratio, p < 0.002) and in right ventricular function indexes measured at rest (+0.21 L in cardiac index [CI], p < 0.01; and +3.0 ml in stroke volume, p < 0.01) and during exercise (+0.9 L in CI, p < 0.002; +10.0 ml in stroke volume index, p < 0.002; and +20% in ejection fraction [EF], p < 0.002). A significant correlation was found between pre- to postoperative changes in the EF response to exercise and changes in the RV/TLC ratio (R = -0.68; p = 0.01). We conclude that a significant improvement in right ventricular performance, particularly during exercise, can occur 6 mo after bilateral LVRS.     

Bronchoscopic lung volume reduction in severe emphysema

Lung volume reduction surgery (LVRS) produces physiological, symptomatic, and survival benefits in selected patients with advanced emphysema. Because it is associated with significant morbidity, mortality, and cost, nonsurgical alternatives for achieving volume reduction have been developed. Three bronchoscopic lung volume reduction (BLVR) approaches have shown promise and reached later-stage clinical trials. These include the following: (1) placement of endobronchial one-way valves designed to promote atelectasis by blocking inspiratory flow; (2) formation of airway bypass tracts using a radiofrequency catheter designed to facilitate emptying of damaged lung regions with long expiratory times; and (3) instillation of biological adhesives designed to collapse and remodel hyperinflated lung. The limited clinical data currently available suggest that all three techniques are reasonably safe. However, efficacy signals have been substantially smaller and less durable than those observed after LVRS. Studies to optimize patient selection, refine treatment strategies, characterize procedural safety, elucidate mechanisms of action, and characterize short- and longer-term effectiveness of these approaches are ongoing. Results will be available over the next few years and will determine whether BLVR represents a safe and effective alternative to LVRS.     

Increased effective lung volume following lung volume reduction surgery in emphysema

STUDY OBJECTIVES: Lung volume reduction surgery (LVRS) for emphysema has a variable effect on spirometry with improvement linked to increases in lung elastic recoil. The mechanism by which recoil increases following LVRS has not been described completely. This study examines preoperative and postoperative pulmonary function to describe a mechanism for changes in airflow obstruction. DESIGN: Change in pulmonary function following LVRS. Setting : Public teaching hospital in Australia. PATIENTS: Patients with severe emphysema and pulmonary function measurements made before and after LVRS. MEASUREMENTS: Routine pulmonary function testing performed with ventilated lung alveolar volume (VA) derived from the gas transfer measurement used as a proxy for the effective lung volume. RESULTS: Pulmonary function tests from 36 consecutive patients with measurements made at the same laboratory were analyzed. The mean FEV(1) was 29.1% predicted presurgery and increased following LVRS from 0.900 L (SD, 0.427 L) to 1.283 L (SD, 0.511 L; p < 0.0001) and TLC (143% predicted) decreased from 8.19 L (SD, 1.492 L) to 7.07 L (SD, 1.52 L; p < 0.0001; n = 35). The mean VA increased by 0.674 L (SD, 0.733 L) from 4.04 to 4.72 L (p < 0.0001; n = 34). The change in FEV(1) correlated well with the change in VA (r = 0.63). The change in FEV(1) in those patients whose VAs did not increase (n = 7) was not significant. CONCLUSIONS: The increase in VA reflects an increase of functional or ventilating lung volume and is associated with an improvement in spirometry following LVRS.     

Bone mineral density improvement after lung volume reduction surgery for severe emphysema

BACKGROUND: In patients with severe emphysema, bone mineral density (BMD) is reduced and the risk of osteoporosis is increased. STUDY OBJECTIVES: To identify the impact of lung volume reduction surgery on BMD. DESIGN: Prospective cohort study. SETTING: University hospital. PATIENTS AND INTERVENTIONS: Forty emphysematous patients, all receiving oral steroid therapy, underwent bilateral lung volume reduction surgery. Thirty similar patients, who refused the operation, followed a standard respiratory rehabilitation program. MEASUREMENTS: All subjects were evaluated pretreatment and 12 months posttreatment for respiratory function, nutritional status, and bone-related biochemical parameters. BMD was assessed by dual-energy radiograph absorptiometry. RESULTS: After surgery, we observed significant improvements in respiratory function (FEV1, + 18.8% [p < 0.01]; residual volume [RV], -29.6% [p < 0.001]; diffusing capacity of the lung for carbon monoxide [Dlco], + 21.6% [p < 0.01]) nutritional parameters (fat-free mass, + 6.0% [p < 0.01]), levels of bone-related hormones (free-testosterone, + 20.5% [p < 0.01]; parathormone, -11.2% [p < 0.01]), bone turnover markers (osteocalcin, -12.7% [p < 0.05]; bone-alkaline-phosphatase, -14.0% [p < 0.05]; beta-crosslaps, -33.6% [p < 0.001]), BMD (lumbar, + 8.8% [p < 0.01]; femoral, + 5.5% [p < 0.01]), and T-score (lumbar, + 21.0% [p < 0.01]; femoral, + 12.4% [p < 0.01]) with reduction in osteoporosis rate (50 to 25%). Nineteen patients who had undergone surgery were able to discontinue treatment with oral steroids. These subjects showed a more significant improvement in BMD (lumbar, + 9.6%; femoral, + 6.8%; p < 0.001) and T-score (lumbar, + 27.3%; femoral, + 14.3%; p < 0.001). The remaining 21 patients who had undergone surgery experienced significant improvement compared to respiratory rehabilitation subjects despite continued therapy with oral steroids (BMD: lumbar, + 4.5% vs -0.7%, respectively [p < 0.01]; femoral, + 2.7% vs -1.1%, respectively [p < 0.05]; T-score: lumbar, + 14 vs -2.1, respectively [p < 0.01]; femoral, + 7.4 vs -2.7, respectively [p < 0.01]). The increase in lumbar BMD was correlated with the surgical reduction of RV (p = 0.02) and with the increase in Dlco (p = 0.01) and fat-free mass (p = 0.01). CONCLUSIONS: Lung volume reduction surgery significantly improves BMD compared to respiratory rehabilitation therapy, even in patients requiring oral steroids. The increase in BMD correlates with RV, Dlco, and fat-free mass, suggesting that the restoration of respiratory dynamics, gas exchange, and nutritional status induces improvement in bone metabolism and mineral content.     

Effect of lung volume reduction surgery on diaphragm length in severe chronic obstructive pulmonary disease

Lung volume reduction surgery (LVRS) has been suggested as improving respiratory mechanics in patients with severe chronic obstructive pulmonary disease (COPD). We hypothesized that LVRS might lengthen the diaphragm, increase its area of apposition with the chest wall, and thereby improve its mechanical function. To determine the effect of bilateral LVRS on diaphragm length, we measured diaphragm length at TLC, using plain chest roentgenograms (CXRs), in 25 patients (11 males and 14 females) before LVRS and 3 to 6 mo after LVRS. A subgroup of seven patients (reference data) also had diaphragm length measurements made with CXRs, using films made within a year before their presurgical evaluation. Right hemidiaphragm silhouette length (PADL) and the length of the most vertically oriented portion of the right hemidiaphragm muscle (VDML) were measured. Diaphragm dome height was determined from the: (1) distance between the dome and transverse diameter at the manubrium; and (2) highest point of the dome referenced horizontally to the vertebral column. Patients also underwent spirometry, measurements of lung volumes and diffusion capacity, an incremental symptom-limited maximum exercise test, and measurements of 6 min walk distance (6MWD) and transdiaphragmatic pressures during maximum static inspiratory efforts (Pdimax sniff) and bilateral supramaximal electrophrenic twitch stimulation (Pditwitch) both before and 3 mo after LVRS. Patients were 58 +/- 8 yr of age, with severe COPD and hyperinflation (FEV1 = 0.68 +/- 0.23 L, FVC = 2.56 +/- 7.3 L, and TLC = 143 +/- 22% predicted). Following LVRS, PADL increased by 4% (from 13.9 +/- 1.9 cm to 14.5 +/- 1.7 cm; p = 0.02), VDML increased by 44% (from 2.08 +/- 1.5 cm to 3.00 +/- 1.6 cm, p = 0.01), and diaphragm dome height increased by more than 10%. In contrast, diaphragm lengths were similar in subjects with CXRs made before LVRS and within 1 yr before evaluation. The increase in diaphragm length correlated directly with postoperative reductions in TLC and RV, and also with increases in transdiaphragmatic pressure with maximal sniff (Pdimax sniff), maximal oxygen consumption (V O2max), maximal minute ventilation (V Emax), and maximum voluntary ventilation following LVRS. We conclude that LVRS leads to a significant increase in diaphragm length, especially in the area of apposition of the diaphragm with the rib cage. Diaphragm lengthening after LVRS is most likely the result of a reduction in lung volume. Increases in diaphragm length after LVRS correlate with postoperative improvements in diaphragm strength, exercise capacity, and maximum voluntary ventilation.     

Lung volume reduction surgery for emphysema and bullous pulmonary emphysema

The improvement of respiratory symptoms for emphysematous patients by surgery is a concept that has evolved over time. Initially used for giant bullae, this surgery was then applied to patients with diffuse microbullous emphysema. The physiological and pathological concepts underlying these surgical procedures are the same in both cases: improve respiratory performance by reducing the high intrapleural pressure. The functional benefit of lung volume reduction surgery (LVRS) in the severe diffuse emphysema has been validated by the National Emphysema Treatment Trial (NETT) and the later studies which allowed to identify prognostic factors. The quality of the clinical, morphological and functional data made it possible to develop recommendations now widely used in current practice. Surgery for giant bullae occurring on little or moderately emphysematous lung is often a simpler approach but also requires specialised support to optimize its results.     

Surgical aspects and techniques of lung volume reduction surgery for severe emphysema.

Lung volume reduction surgery (LVRS) has become an accepted procedure for palliative treatment of diffuse, nonbullous emphysema. Single or multiple peripheral segmental wedge resections of the most destroyed areas of the lungs are performed with the use of stapling devices, in order to decrease hyperinflation and restore diaphragmatic function. Median sternotomy, videoendoscopy or anterior muscle sparing thoracotomies have been used as surgical approaches. The functional improvement after bilateral resections exceed those after a unilateral approach. LVRS has demonstrated its potential as an alternative to transplantation, and with growing experience, the indications for the procedure have been widened. In selected patients with peripheral lung cancer who have been considered unsuitable for a surgical resection, the combination of both tumour resection and LVRS has successfully been performed. In contrast to LVRS, laser surgery of the emphysematous lung has been abandoned in most institutions.     

Improvements in thoracic movement following lung volume reduction surgery in patients with severe emphysema

In twelve patients with severe emphysema who underwent lung volume reduction surgery (LVRS), we assessed the results of dyspnea scale, pulmonary function, 6-minute walk distance (6MD), and thoracic movement prior to and 6 months following LVRS. Postoperatively, forced expiratory volume (FEV1), maximum inspiratory mouth pressures (MIP), maximum expiratory mouth pressures (MEP), maximum voluntary ventilation (MVV), diffusing capacity for carbon monoxide (DLCO), partial pressure of oxygen (PaO2) and 6MD were significantly increased with the decrease in dyspnea scale and lung hyperinflation. Thoracic movement, as assessed by the bilateral lung area ratio of the mid-sagittal dimension of dynamic magnetic resonance imaging (MRI) at full inspiration to that at full expiration, was significantly increased. The improvement in thoracic movement was significantly correlated with the increases in FEV1, MVV, and MIP, and with the decrease in residual volume (RV), and with the improvement in the dyspnea scale. These findings suggest that LVRS is an effective procedure for improving not only the airflow limitation and gas exchange but also the thoracic movement in severe emphysema, and these improvements may contribute to an increase in exercise performance and relief of dyspnea.     

肺减容术治疗慢性阻塞性肺气肿疗效的临床观察

目的探讨肺减容术(LVRS)对慢性阻塞性肺气肿(COPE)患者的疗效。方法 23例该类患者用直线切缝器切除肺边缘20%～25%弥漫性大泡肺组织,常规用3/0prolene缝线连续往返缝合,必要时3/0prolene缝线加毛毡垫片行褥式缝合。结果本组共23例,采用LVRS治疗,无1例死亡,发生肺泡漏气者等并发症5例(21.7%)。23例中有17例随访,自觉症状均不同程度改善。结论 LVRS对于COPE患者,特别是合并多发性肺大泡患者的近期治疗效果明显,但远期效果仍有待进一步观察。该方法简单易行,易于基层医院推广。     

Radiologic evaluation of emphysema for lung volume reduction surgery

Lung volume reduction surgery has created an opportunity for the advanced imaging of emphysema. Patients with CT or perfusion scintigraphy demonstrating an upper- or lower-lobe-predominant pattern of emphysema have better patient outcomes after LVRS than patients with emphysema diffusely or homogeneously distributed throughout the lungs. Some patients with diffuse or homogeneous emphysema may demonstrate improvement in function or dyspnea after surgery, but the magnitude of the improvement seen is less than in patients with heterogeneous emphysema, and the duration of benefit is not known. An ongoing, multicenter National Heart, Lung, and Blood Institute (NHLBI)/Health Care Financing Association (HCFA) sponsored trial of LVRS aims to determine whether LVRS together with maximal medical therapy and pulmonary rehabilitation improves patient outcomes compared with maximal medical therapy and pulmonary rehabilitation alone. This study will address the duration of clinical benefit and the cost-effectiveness of LVRS.     

经支气管镜活瓣植入肺减容术治疗重度肺气肿36例疗效观察

目的 研究经支气管镜活瓣(EBV)植入肺减容术治疗重度肺气肿的疗效.方法 回顾性分析从2016年10月～2019年2月,于我院实施EBV植入肺减容术治疗的36例重度肺气肿患者的相关病历资料,记为研究组.另取从2013年2月～2015年6月,于我院接受开胸肺减容术治疗的36例重度肺气肿患者作为对照组.比较治疗前后两组肺功...     

Short- and long-term functional results after lung volume reduction surgery for severe emphysema.

Lung volume reduction surgery (LVRS) has emerged as a surgical therapeutic intervention for advanced emphysema. Designed for the relief of dyspnoea, LVRS has been demonstrated to be efficacious in a subset of carefully selected patients. Short-term improvements in dyspnoea are accompanied by improvements in forced expiratory volume in one second ranging 13-96%. Lung volumes likewise improve, with lessening of trapped gas, residual volume, and total lung capacity. Improvements in functional status and quality-of-life measures parallel the improvements in dyspnoea and lung function. One preliminary study suggests that life expectancy after 3 yrs may be improved following LVRS. Many questions regarding lung volume reduction surgery in terms of operative technique, selection of patients, and outcome remain to be answered. Data are available which begin to address some of these issues. Bilateral procedures have greater short-term improvements than unilateral procedures, but the rate of loss of function following the surgery may also be greater. Stapled resection of lung tissue has been demonstrated to be superior to laser ablation. In a majority of reports, outcome is superior in patients with heterogeneous distribution of their emphysema, and patients with alpha1-proteinase inhibitor deficiency emphysema do less well than patients with smoker's emphysema.     

Cardiac morphology in lung volume reduction surgery for endstage emphysema

Lung volume reduction surgery for endstage emphysema produces significant improvements in various pulmonary parameters, but its effects on cardiac morphology and function have not been clearly defined. Ten patients scheduled for lung volume reduction surgery underwent pulmonary function testing, right-heart catheterization, and electron beam computed tomography of the heart. These studies were repeated 12-16 weeks after the procedure. Quantitative assessments of right and left ventricular function and left ventricular muscle mass were obtained. Postoperatively, all patients showed significant improvements in forced expiratory volume at one minute compared to the preoperative value (1.57 +/- 0.24 L versus 1.10 +/- 0.21 L), predicted residual lung volume (115% +/- 15% versus 205% +/- 15%), and 6-minute walk test (318 +/- 17 m versus 267 +/- 24 m). There were no significant differences between postoperative and preoperative right ventricular end-diastolic volumes (167.3 +/- 21.2 mL versus 169.2 +/- 17.3 mL) or left ventricular end-diastolic volumes (112.5 +/- 10.2 mL versus 119.2 +/- 9.7 mL).     

Core to rind distribution of severe emphysema predicts outcome of lung volume reduction surgery.

Computed tomography (CT) has shown that emphysema is more extensive in the inner (core) region than in the outer (rind) region of the lung. It has been suggested that the concentration of emphysematous lesions in the outer rind leads to a better outcome following lung volume reduction surgery (LVRS) because these regions tend to be more surgically accessible. The present study used a recently described, computer-based CT scan analysis to quantify severe emphysema (lung inflation > 10.2 ml gas/g tissue), mild/moderate emphysema (lung inflation = 10.2 to 6.0 ml gas/g tissue), and normal lung tissue (lung inflation < 6.0 ml gas/g tissue) present in the core and rind of the lung in 21 LVRS patients. The results show that the quantification of severe emphysema independently predicts change in maximal exercise response and FEV(1). We conclude that a greater extent of severe emphysema in the rind of the upper lung predicts greater benefit from LVRS because it identifies the lesions most accessible to removal by LVRS.