Reduction pneumoplasty versus respiratory rehabilitation in severe emphysema: a randomized study. Pulmonary Emphysema Research Group

Quasilobar minimalist lung volume reduction surgery

 

OBJECTIVES

Our goal was to assess the results and the costs of the quasilobar minimalist (QLM) thoracoscopic lung volume reduction (LVR) surgical method developed to minimize the trauma from the operation and the anaesthesia and to maximize the effect of the lobar volume reduction.

METHODS

Forty patients with severe emphysema underwent QLM-LVR that entailed adoption of sole intercostal block analgesia and lobar plication through a single thoracoscopic incision. Results were compared after propensity matching with 2 control groups undergoing non-awake resectional LVR with double-lumen tracheal intubation or awake non-resectional LVR by plication with thoracic epidural anaesthesia. As a result, we had 3 matched groups of 30 patients each.

RESULTS

Baseline forced expiratory volume in 1 s, residual volume, the 6-min walking test and the modified Medical Research Council dyspnoea index were 0.77 ± 0.18, 4.97 ± 0.6, 328 ± 65 and 3.3 ± 0.7, respectively, with no intergroup difference after propensity score matching. The visual pain score was better (P < 0.007), the hospital stay was shorter (P < 0.04) and overall costs were lower (P < 0.04) in the QLM-LVR group than in the control groups. The morbidity rate was lower with QLM-LVR than with non-awake resectional-LVR (P = 0.006). Significant improvements (P < 0.001) occurred in all study groups during the follow-up period. At 24 months, improvements in residual volume and dyspnoea index were significantly better with QLM-LVR (P < 0.04).

CONCLUSIONS

QLM-LVR proved safe and showed better perioperative outcomes and lower procedure-related costs than the control groups. Similar clinical benefit occurred at 12 months, but absolute improvements in residual volume and dyspnoea index were better in the QLM-LVR group at 24 months.

Lung transplantation for emphysema

Lung transplantation (LT) is proved to be effective in patients with end-stage lung disease who are failing optimal therapy. Chronic obstructive pulmonary disease (emphysema) is the most common indication for adult lung transplantation. As most patients with emphysema (EMP) can survive long term, it could be difficult to decide which patient should be listed for LT. LT is a complex surgery. Therefore, it is extremely important to choose a recipient in whom expected survival is at less equal or comparable to the survival without surgery. This paper reviews patient selection, bridging strategies until lung transplantation, surgical approach and choice of the procedure, and functional outcome in emphysema recipients.

Surgical and endoscopic interventions that reduce lung volume for emphysema: a systemic review and meta-analysis

BACKGROUND

Severe emphysema is a debilitating condition with few treatment options. Lung volume reduction procedures in the treatment of severe emphysema have shown excellent results in selected patients but their exact role remains unclear with studies reporting a wide variation in outcomes. We therefore aimed to evaluate the effects of volume reduction.

METHODS

We did a systematic review and meta-analysis. We searched MEDLINE on Sept 29, 2016, for trials of lung volume reduction in patients with emphysema, and we did an updated search on Embase and PubMed on June 18, 2018. We only included randomised controlled studies published in English evaluating the intervention with either sham or standard of care. Inclusion was limited to trials of techniques in which there was sustainable volume reduction. Primary outcomes were residual volume, FEV₁, St George's Respiratory Questionnaire (SGRQ), and 6-min walk distance (6MWT). Secondary outcomes were severe adverse events (including mortality), short-term mortality, and overall mortality. We extracted summary level data from the trial publications and where necessary we obtained unpublished data. A random-effects model with the I² statistic was used to determine heterogeneity and trial weight in each analysis. The study is registered with the PROSPERO database, number CRD42016045705.

FINDINGS

We identified 4747 references in the search, and included 20 randomised controlled trials of lung volume reduction involving 2794 participants with emphysema. Following lung volume reduction from any of the interventions in pooled analyses (ie, surgery, endobronchial valve, endobronchial coil, or sclerosing agents), the mean differences compared with the control were reduction in residual volume of 0·58 L (95% CI -0·80 to -0·37), increase in FEV₁ of 15·87% (95% CI 12·27 to 19·47), improvement in 6MWT of 43·28 m (31·36 to 55·21), and reduction in the SGRQ of 9·39 points (-10·92 to -7·86). The odds ratio for a severe adverse event, which included mortality, was 6·21 (95% CI 4·02 to 9·58) following intervention. Regression analysis showed improvements relative to the degree of volume reduction: FEV₁ (r²=0·86; p<0·0001), 6MWT (r²=0·77; p<0·0001), and SGRQ (r²=0·70; p<0·0001). Most studies were at high risk of bias for lack of blinding, and heterogeneity was high for some outcomes when pooled across all interventions, but was generally lower in the subgroups by intervention type.

INTERPRETATION

Despite limitations of high risk of bias and heterogeneity for some analyses, our results provide support that lung volume reduction in patients with severe emphysema on maximal medical treatment has clinically meaningful benefits. These benefits should be considered alongside potential adverse events.

FUNDING

None.

Postoperative complications and management after lung volume reduction surgery

The aim of lung volume reduction surgery (LVRS) for patients suffering from severe emphysema is to improve lung function and palliate dyspnea. Careful patient selection in a multidisciplinary approach in a high-volume center is mandatory for a successful outcome. Pulmonary complications including air leak and pneumonia as well as cardiac complications are the most common complications after LVRS. The following article will focus on most common complications observed after LVRS and review the management strategies to improve surgical outcome.

Staged unilateral lung volume reduction surgery: from mini-invasive to minimalist treatment strategies

Lung volume reduction surgery (LVRS) entailing unilateral or bilateral non-anatomical resection of severely damaged emphysematous tissue carried out by thoracoscopic or open surgical approaches, under general anesthesia with single-lung ventilation, has resulted in significant and long-lasting clinical and functional benefit. Unfortunately, the morbidity rates reported by simultaneous bilateral resectional LVRS has led to raise criticism regarding its cost-effectiveness and has stimulated in recent years the development of less invasive bronchoscopic and surgical non-resectional methods of treatment that are preferentially performed in a staged unilateral fashion. We had previously proposed an innovative LVRS modality, which did not entail any resection of lung tissue and was electively carried out according to a staged unilateral strategy by a multiport thoracoscopic access, through thoracic epidural anesthesia in conscious, spontaneously ventilating patients (awake LVRS). The awake LVRS resulted in significant clinical benefit paralleling that achieved by the resectional method with lower morbidity rates and shorter hospital stay. Moreover, the awake LVRS proved also suitable to be employed in stringently selected patients to perform redo procedures following previous successful bilateral LVRS. More recently, in order to minimize the global surgery- and anesthesia-related traumas, we have modified our original non-resectional method by adopting a single thoracoscopic access as well as an anesthesia protocol entailing use of a simple intercostal block with target control sedation, to realize an ultra-minimally invasive or minimalist LVRS. Hence, a deeper investigation of the pros and cons of staged unilateral LVRS strategies as well as of the novel surgical non-resectional and redo LVRS is warranted in order to verify, the optimal strategies of treatment, which will prove to reduce the typical LVRS-related morbidity while assuring the most durable benefit in patients with advanced emphysema.

Is preoperative hypercapnia a justified exclusion criterion for lung volume reduction surgery?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether potential surgical candidates for lung volume reduction surgery (LVRS), who have preoperative hypercapnia, should be excluded on this basis. Using the reported search, 45 papers were found, of which 14 represented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. Of these, seven papers showed a significant (P < 0.05) improvement in postoperative forced expiratory volume in 1 second (FEV1) at up to 6 months in hypercapnic patients. There were six papers which found significant decreases in postoperative arterial carbon dioxide partial pressures (PaCO2) levels following LVRS up to 6 months. There were three papers which showed significant (P < 0.05) improvements in the 6-min walk test in hypercapnic patients following LVRS. Only two papers showed an increased operative mortality in the hypercapnic group compared to the normocapnic group, while nine papers did not find a difference in perioperative mortality. The only randomized controlled study, the landmark NETT study, excluded patients with severe hypercapnia (PaCO2 >55 mmHg and >60 mmHg) and the mean PaCO2 in the surgical and medical group were 43.3 ± 5.9 and 43.0 ± 5.8, respectively. We conclude that the evidence is not strong enough to consider hypercapnia in isolation as high risk or unsuitable for LVRS.

Lung volume reduction surgery for diffuse emphysema

BACKGROUND

Lung volume reduction surgery (LVRS) performed to treat patients with severe diffuse emphysema was reintroduced in the nineties. Lung volume reduction surgery aims to resect damaged emphysematous lung tissue, thereby increasing elastic properties of the lung. This treatment is hypothesised to improve long-term daily functioning and quality of life, although it may be costly and may be associated with risks of morbidity and mortality. Ten years have passed since the last version of this review was prepared, prompting us to perform an update.

OBJECTIVES

The objective of this review was to gather all available evidence from randomised controlled trials comparing the effectiveness of lung volume reduction surgery (LVRS) versus non-surgical standard therapy in improving health outcomes for patients with severe diffuse emphysema. Secondary objectives included determining which subgroup of patients benefit from LVRS and for which patients LVRS is contraindicated, to establish the postoperative complications of LVRS and its morbidity and mortality, to determine which surgical approaches for LVRS are most effective and to calculate the cost-effectiveness of LVRS.

SEARCH METHODS

We identified RCTs by using the Cochrane Airways Group Chronic Obstructive Pulmonary Disease (COPD) register, in addition to the online clinical trials registers. Searches are current to April 2016.

SELECTION CRITERIA

We included RCTs that studied the safety and efficacy of LVRS in participants with diffuse emphysema. We excluded studies that investigated giant or bullous emphysema.

DATA COLLECTION AND ANALYSIS

Two independent review authors assessed trials for inclusion and extracted data. When possible, we combined data from more than one study in a meta-analysis using RevMan 5 software.

MAIN RESULTS

We identified two new studies (89 participants) in this updated review. A total of 11 studies (1760 participants) met the entry criteria of the review, one of which accounted for 68% of recruited participants. The quality of evidence ranged from low to moderate owing to an unclear risk of bias across many studies, lack of blinding and low participant numbers for some outcomes. Eight of the studies compared LVRS versus standard medical care, one compared two closure techniques (stapling vs laser ablation), one looked at the effect of buttressing the staple line on the effectiveness of LVRS and one compared traditional 'resectional' LVRS with a non-resectional surgical approach. Participants completed a mandatory course of pulmonary rehabilitation/physical training before the procedure commenced. Short-term mortality was higher for LVRS (odds ratio (OR) 6.16, 95% confidence interval (CI) 3.22 to 11.79; 1489 participants; five studies; moderate-quality evidence) than for control, but long-term mortality favoured LVRS (OR 0.76, 95% CI 0.61 to 0.95; 1280 participants; two studies; moderate-quality evidence). Participants identified post hoc as being at high risk of death from surgery were those with particularly impaired lung function, poor diffusing capacity and/or homogenous emphysema. Participants with upper lobe-predominant emphysema and low baseline exercise capacity showed the most favourable outcomes related to mortality, as investigators reported no significant differences in early mortality between participants treated with LVRS and those in the control group (OR 0.87, 95% CI 0.23 to 3.29; 290 participants; one study), as well as significantly lower mortality at the end of follow-up for LVRS compared with control (OR 0.45, 95% CI 0.26 to 0.78; 290 participants; one study). Trials in this review furthermore provided evidence of low to moderate quality showing that improvements in lung function parameters other than forced expiratory volume in one second (FEV1), quality of life and exercise capacity were more likely with LVRS than with usual follow-up. Adverse events were more common with LVRS than with control, specifically the occurrence of (persistent) air leaks, pulmonary morbidity (e.g. pneumonia) and cardiovascular morbidity. Although LVRS leads to an increase in quality-adjusted life-years (QALYs), the procedure is relatively costly overall.

AUTHORS' CONCLUSIONS

Lung volume reduction surgery, an effective treatment for selected patients with severe emphysema, may lead to better health status and lung function outcomes, specifically for patients who have upper lobe-predominant emphysema with low exercise capacity, but the procedure is associated with risks of early mortality and adverse events.

Reduction in resting energy expenditure following lung volume reduction surgery in subjects with chronic obstructive pulmonary disease

Study objectives: Some subjects with COPD have an elevated resting energy expenditure (REE)which may be related to an increased work of breathing at rest. The purpose of this study was to examine the effect of lung volume reduction surgery (LVRS) on REE and body weight. Design: Ten subjects with COPD were recruited (mean age + SD = 61.4 + 6.1 years). At baseline (which was following preoperative pulmonary rehabilitation) and four months following LVRS (combined with postoperative pulmonary rehabilitation), each subject had tests of lung function, REE via indirect calorimetry using a canopy system, six minute walk distance (6MWD) and quality of life (QoL) using the St George's Hospital Respiratory Questionnaire (SGRQ). Measurements: The FEV, (% predicted) increased from 27.7 + 5.8% (mean + SD) at baseline to 33.9 + 7.8% following LVRS (P < 0.05). REE (% predicted) was 110 + 9.8% at baseline and decreased to 106 + 6.7% following LVRS (P = 0.04). Body mass index (BMI) following LVRS was unchanged (P = 0.67). No correlation between the change in BMI and change in REE was shown (r2 = 0.3, P = 0.1). Therewas a significant improvement in QoL following LVRS (P < 0.001). 6MWD also significantly increased from 354 + 83 m to 412 + 82 m following LVRS (P = 0.001). Conclusion: Whilst there was an increase in lung function and a reduction in REE following LVRS, there was no corresponding change to body weight. The improvement in REE following LVRS may be related to an improvement in work of breathing.

Supported and unsupported arm exercise capacity following lung volume reduction surgery: a pilot study

Study Objectives: Lung volume reduction surgery (LVRS) has been shown to improve lung function, leg exercise capacity and quality of life in subjects with severe COPD. This is the first study to examine the effect of LVRS on supported and unsupported arm exercise capacity. Design: Eight subjects with COPD (% pred FEV1 ±SD = 31.1 ± 9.8%) completed testing. At baseline (TI), after eight weeks pulmonary rehabilitation (T2) and four months after LVRS (T3), each subject had tests of lung function, and performed three symptom-limited exercise tests to peak work capacity:supported arm exercise (SAE), unsupported arm exercise (UAE) and leg exercise (LE).Measurements: The FEV1 (% pred) increased from 27.8 ± 7.4 (mean ± SD) at T2 to 36.3 ± 7.1 at T3 (P <0.05). Peak oxygen consumption (VO2) remained similar from TI to T2 for SAE, UAE and LE (all P=1.0) but increased from T2 to T3 (P <0.05) (SAE: T2 = 0.59 ± 0.2 L/min,T3 = 0.72 ± 0.1 L/min; UAE: T2 = 0.45 ± 0.1 L/min, T3 = 0.54 ± 0.1 L/min; LE:T2-0.68 ± 0.2 L/min, T3 = 0.81 ± 0.2 L/min). The ratio of end-expiratory lung volume to total lung capacity was reduced at peak SAE and LE from T2 to T3 (P < 0.01) (SAE:T2 = 81 ± 4.0%, T3 = 76 ± 2.7%; LE: T2-81 ± 5.1%, T3 = 75 ± 3.6%). Conclusion: There was a significant increase in SAE and UAE capacity following LVRS. Dynamic hyperinflation wras reduced during SAE following LVRS.

The complex care of severe emphysema: role of awake lung volume reduction surgery

The resectional lung volume reduction surgery (LVRS) procedure entailing nonanatomic resection of destroyed lung regions through general anesthesia with single-lung ventilation has shown to offer significant and long-lasting improvements in respiratory function, exercise capacity, quality of life and survival, particularly in patients with upper-lobe predominant emphysema and low exercise capacity. However mortality and morbidity rates as high as 5% and 59%, respectively, have led to a progressive underuse and have stimulated investigation towards less invasive surgical and bronchoscopic nonresectional methods that could assure equivalent clinical results with less morbidity. We have developed an original nonresectional LVRS method, which entails plication of the most severely emphysematous target areas performed in awake patients through thoracic epidural anesthesia (TEA). Clinical results of this ultra-minimally invasive procedure have been highly encouraging and in a uni-center randomized study, intermediate-term outcomes paralleled those of resectional LVRS with shorter hospital stay and fewer side-effects. In this review article we analyze indications, technical details and results of awake LVRS taking into consideration the available data from the literature.

Chronic obstructive pulmonary disease

COPD is characterized by airflow limitation that is not fully reversible. The morphological basis for airflow obstruction results from a varying combination of obstructive changes in peripheral conducting airways and destructive changes in respiratory bronchioles, alveolar ducts, and alveoli. A reduction of vascularity within the alveolar septa has been reported in emphysema. Typical physiological changes reflect these structural abnormalities. Spirometry documents airflow obstruction when the FEV1/FVC ratio is reduced below the lower limit of normality, although in early disease stages FEV1 and airway conductance are not affected. Current guidelines recommend testing for bronchoreversibility at least once and the postbronchodilator FEV1/FVC be used for COPD diagnosis; the nature of bronchodilator response remains controversial, however. One major functional consequence of altered lung mechanics is lung hyperinflation. FRC may increase as a result of static or dynamic mechanisms, or both. The link between dynamic lung hyperinflation and expiratory flow limitation during tidal breathing has been demonstrated. Hyperinflation may increase the load on inspiratory muscles, with resulting length adaptation of diaphragm. Reduction of exercise tolerance is frequently noted, with compelling evidence that breathlessness and altered lung mechanics play a major role. Lung function measurements have been traditionally used as prognostic indices and to monitor disease progression; FEV1 has been most widely used. An increase in FVC is also considered as proof of bronchodilatation. Decades of work has provided insight into the histological, functional, and biological features of COPD. This has provided a clearer understanding of important pathobiological processes and has provided additional therapeutic options.

Evidence-based risk assessment and recommendations for physical activity clearance: respiratory disease

The 2 most common respiratory diseases are chronic obstructive pulmonary disease (COPD) and asthma. Growing evidence supports the benefits of exercise for all patients with these diseases. Due to the etiology of COPD and the pathophysiology of asthma, there may be some additional risks of exercise for these patients, and hence accurate risk assessment and clearance is needed before patients start exercising. The purpose of this review was to evaluate the available literature regarding the risks of exercise for patients with respiratory disease and provide evidence-based recommendations to guide the screening process. A systematic review of 4 databases was performed. The literature was searched to identify adverse events specific to exercise. For COPD, 102 randomized controlled trials that involved an exercise intervention were included (n = 6938). No study directly assessed the risk of exercise, and only 15 commented on exercise-related adverse events. For asthma, 30 studies of mixed methodologies were included (n = 1278). One study directly assessed the risk of exercise, and 15 commented on exercise-related adverse events. No exercise-related fatalities were reported. The majority of adverse events in COPD patients were musculoskeletal or cardiovascular in nature. In asthma patients, exercise-induced bronchoconstriction and (or) asthma symptoms were the primary adverse events. There is no direct evidence regarding the risk of exercise for patients with COPD or asthma. However, based on the available literature, it would appear that with adequate screening and optimal medical therapy, the risk of exercise for these respiratory patients is low.

Long-term survival analysis of the Canadian Lung Volume Reduction Surgery trial

BACKGROUND

The Canadian Lung Volume Reduction Surgery (CLVRS) trial was a multicentered randomized controlled trial that concluded that lung volume reduction surgery improves functional status and health-related quality of life (for at least 2 years) in selected patients with advanced emphysema.

METHODS

This retrospective observational study assessed the long-term survival of patients enrolled in the CLVRS at 8 to 10 years after randomization. Vital statistics were gathered through telephone contact, physician records, and municipal obituaries. Survival analysis was undertaken using Kaplan-Meier and the Cox proportional hazards models.

RESULTS

Fifty-two patients (84% of the initial 62 patients randomized) had a median survival time of 4.11 years. A 16-month survival advantage and a 20% reduction in mortality was observed in the LVRS group as compared with the best medical care group. Although clinically meaningful, these differences were not statistically significant.

CONCLUSIONS

These findings echo those of other published reports and demonstrate the potential long-term benefit of LVRS in the treatment of end-stage emphysema.

Several clinical interests regarding lung volume reduction surgery for severe emphysema: meta-analysis and systematic review of randomized controlled trials

Objectives

We aim to address several clinical interests regarding lung volume reduction surgery (LVRS) for severe emphysema using meta-analysis and systematic review of randomized controlled trials (RCTs).

Methods

Eight RCTs published from 1999 to 2010 were identified and synthesized to compare the efficacy and safety of LVRS vs conservative medical therapy. One RCT was obtained regarding comparison of median sternotomy (MS) and video-assisted thoracoscopic surgery (VATS). And three RCTs were available evaluating clinical efficacy of using bovine pericardium for buttressing, autologous fibrin sealant and BioGlue, respectively.

Results

Odds ratio (95%CI), expressed as the mortality of group A (the group underwent LVRS) versus group B (conservative medical therapies), was 5.16(2.84, 9.35) in 3 months, 3(0.94, 9.57) in 6 months, 1.05(0.82, 1.33) in 12 months, respectively. On the 3^rd, 6^th and 12^th month, all lung function indices of group A were improved more significantly as compared with group B. PaO2 and PaCO2 on the 6^th and 12^th month showed the same trend. 6MWD of group A on the 6^th month and 12^th month were improved significantly than of group B, despite no difference on the 3^rd month. Quality of life (QOL) of group A was better than of group B in 6 and 12 months. VATS is preferred to MS, due to the earlier recovery and lower cost. And autologous fibrin sealant and BioGlue seems to be the efficacious methods to reduce air leak following LVRS.

Conclusions

LVRS offers the more benefits regarding survival, lung function, gas exchange, exercise capacity and QOL, despite the higher mortality in initial three postoperative months. LVRS, with the optimization of surgical approach and material for reinforcement of the staple lines, should be recommended to patients suffering from severe heterogeneous emphysema.

Lung transplantation and lung volume reduction surgery

Since the publication of the last edition of the Handbook of Physiology, lung transplantation has become widely available, via specialized centers, for a variety of end-stage lung diseases. Lung volume reduction surgery, a procedure for emphysema first conceptualized in the 1950s, electrified the pulmonary medicine community when it was rediscovered in the 1990s. In parallel with their technical and clinical refinement, extensive investigation has explored the unique physiology of these procedures. In the case of lung transplantation, relevant issues include the discrepant mechanical function of the donor lungs and recipient thorax, the effects of surgical denervation, acute and chronic rejection, respiratory, chest wall, and limb muscle function, and response to exercise. For lung volume reduction surgery, there have been new insights into the counterintuitive observation that lung function in severe emphysema can be improved by resecting the most diseased portions of the lungs. For both procedures, insights from physiology have fed back to clinicians to refine patient selection and to scientists to design clinical trials. This section will first provide an overview of the clinical aspects of these procedures, including patient selection, surgical techniques, complications, and outcomes. It then reviews the extensive data on lung and muscle function following transplantation and its complications. Finally, it reviews the insights from the last 15 years on the mechanisms whereby removal of lung from an emphysema patient can improve the function of the lung left behind.

Variations of inflammatory mediators and alpha1-antitrypsin levels after lung volume reduction surgery for emphysema

RATIONALE

In emphysema, chronic inflammation, including protease-antiprotease imbalance, is responsible for declining pulmonary function and progressive cachexia.

OBJECTIVES

To evaluate variations of inflammatory mediators and alpha(1)-antitrypsin levels after lung volume reduction surgery (LVRS) compared with respiratory rehabilitation.

METHODS

A total of 28 patients with moderate to severe emphysema, who underwent video-assisted thoracoscopic LVRS, were compared with 26 similar patients, who refused operation and followed a standardized rehabilitation program, and to a matched healthy group. Respiratory function, body composition, circulating inflammatory mediators, and alpha(1)-antitrypsin levels were evaluated before and 12 months after treatment. Gene expression levels of inflammatory mediators and protease-antiprotease were assessed in emphysematous specimens from 17 operated patients by matching to normal tissue from resection margins.

MEASUREMENTS AND MAIN RESULTS

Significant improvements were only obtained after surgery in respiratory function (FEV(1), +25.2%, P < 0.0001; residual volume [RV], -19.5%, P < 0.0001; diffusing lung capacity for carbon monoxide, +3.3%, P < 0.05) and body composition (fat-free mass, +6.5%, P < 0.01; fat mass, +11.9%, P < 0.01), with decrement of circulating inflammatory mediators (TNF-alpha, -22.2%, P < 0.001; IL-6, -24.5%, P < 0.001; IL-8, -20.0%, P < 0.001) and increment of antiprotease levels (alpha(1)-antitrypsin, +27.0%, P < 0.001). Supportive gene expression analysis demonstrated active inflammation and protease hyperactivity in the resected emphysematous tissue. Reduction of TNF-alpha and IL-6 and increment of alpha(1)-antitrypsin levels significantly correlated with reduction of RV (P = 0.03, P = 0.009, and P = 0.001, respectively), and partially with increment of fat-free mass (P = 0.03, P = 0.02, and P = 0.09, respectively).

CONCLUSIONS

LVRS significantly reduced circulating inflammatory mediators and increased antiprotease levels over respiratory rehabilitation, also improving respiratory function and nutritional status. Correlations of inflammatory mediators and antiprotease levels with RV and, partly, with body composition suggest that elimination of inflammatory emphysematous tissue may explain clinical improvements after surgery.

[Surgical management of COPD distension]

INTRODUCTION

The impressive results seen when giant and compressing lung bullae are resected has inspired pneumonologists and thoracic surgeons to consider the possibility of applying a similar approach to the treatment of respiratory failure due to chronic obstructive pulmonary disease (COPD).

STATE OF THE ART

The major problem with this surgical indication lies in our ability to understand fully the pathophysiology of lesions and thus identify which emphysematous patients will have a response most similar to that achieved in purely bullous disease.

PERSPECTIVES

At the present time consideration should be given as to whether surgery is the only means of reducing pulmonary distension. Indeed, as endoscopic alternatives develop could they reproduce its beneficial effects and what would be their place compared to the surgery?

CONCLUSIONS

While waiting the development of these innovations, if the selection of the candidates is correct, the surgical treatment of lung hyperinflation can temporarily improve the quality of life of these patients by decreasing their dyspnea and increasing their exercise tolerance.

Lung volume reduction surgery in nonheterogeneous emphysema

Patients with a homogeneous type of emphysema have been excluded a priori from LVRS in many centers because of the fear of removing parenchyma, which potentially contributes to gas exchange, and because the observation that heterogeneity of emphysema is a predictor of functional improvement. It is obvious that resection of functionless tissue, such as in heterogeneous emphysema with bullae, can be advised to the patient with a relative low risk. However, as the main positive effect of LVRS is its improvement on respiratory mechanics, it is not surprising that well-selected patients with homogeneous emphysema also benefit from surgery. Their selection has to be done cautiously. It is crucial to exclude patients with a very low functional reserve, such as with diffusing capacity below 20% predicted or with pulmonary hypertension, and with extreme parenchymal loss (vanished lungs) on CT from LVRS. Additionally, cofactors which may potentially interfere with a smooth postoperative course, such as previous recurrent infections, extensive scarring of the lungs, or previous surgery, have to be taken into consideration. When respecting these caveats, LVRS in patients with complete homogeneous emphysema provides a comparable symptomatic and almost the same functional improvement as in patients with heterogeneous emphysema. Although the perioperative mortality is low, patients with homogeneous emphysema have a slightly reduced long-term survival without lung transplantation compared with patients with heterogeneous emphysema. Based on our own experience, we conclude that LVRS can be recommended to selected symptomatic patients with advanced homogenous emphysema associated with severe hyperinflation, if diffusing capacity is not below 20% of predicted values and if the CT scan does not show aspects of vanished lungs.

Lung volume reduction surgery and lung transplantation in chronic obstructive pulmonary disease

Medical treatment of emphysema does not alter the natural progression of the disease. Surgical techniques are an attractive conceptual approach to treat hyperinflation in these patients. Lung volume reduction surgery and lung transplantation are appropriate therapeutic options for a selected population with emphysema. We will review the available evidence to support these approaches.

[Dynamic lung hyperinflation and its clinical implication in COPD]

Static lung hyperinflation is defined as the elevation of end- expiratory lung volume above its predicted value, with no increase in end-expiratory alveolar pressure, which remains equal to atmospheric pressure. Dynamic hyperinflation is the transient increase of this volume above the relaxation volume. In patients with COPD, dynamic hyperinflation is mainly determined by the mechanical properties of the respiratory system. Its measurement relies on plethysmography and, during exercise, inspiratory capacity. During exercise, dynamic hyperinflation attenuates expiratory flow limitation but increases the inspiratory loading and induces functional weakness of the diaphragm. It also has haemodynamic consequences and results in more rapid, shallow breathing and progressive reduction in dynamic lung compliance. These events explain exercise intolerance. Several approaches may help combat dynamic hyperinflation and its deleterious clinical effects: bronchodilators, hyperoxia, helium-oxygen mixtures, lung volume reduction surgery...

Cost-effectiveness of lung volume reduction surgery

Lung volume reduction surgery (LVRS) is a costly procedure that can improve quality and quantity of life. Given the prevalence of emphysema, the costs involved with its management, and resource constraints on all health care delivery systems, evaluating the cost-effectiveness of LVRS is important. In this article, we describe the purposes and principles of cost-effectiveness analysis and how those principles were applied in evaluating LVRS. We present the results of the cost-effectiveness analysis that was conducted alongside the National Emphysema Treatment Trial and other economic studies of LVRS and discuss how these should be interpreted in the context of current reimbursement guidelines.

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.

Changes in arterial oxygenation and self-reported oxygen use after lung volume reduction surgery

RATIONALE

Lung volume reduction surgery (LVRS) is inconsistently reported to improve arterial oxygenation in patients with chronic obstructive pulmonary disease.

OBJECTIVES

We studied the effects of surgery on oxygenation in a large cohort and identified predictors of postoperative oxygenation improvement.

METHODS

We evaluated oxygenation in 1,078 subjects with chronic obstructive pulmonary disease enrolled in the National Emphysema Treatment Trial after LVRS compared with medical control subjects, including arterial blood gases, use of supplemental oxygen during treadmill walking, and self-reported use of oxygen during rest, exertion, and sleep.

MEASUREMENTS AND MAIN RESULTS

Pa(O(2)) breathing room air was equal in medical and surgical subjects at baseline (64.8 vs. 65.0 mm Hg, P = not significant), but lower in medical subjects at 6 months (63.6 vs. 70.0 mm Hg, P < 0.001), 12 months (63.9 vs. 68.7 mm Hg, P < 0.001), and 24 months (62.4 vs. 68.0 mm Hg, P < 0.001). Fewer medical subjects required oxygen for treadmill walking at baseline compared with surgical subjects (46 vs. 53%, P = 0.02). However, more medical subjects required oxygen for this activity at 6 months (49 vs. 33%, P < 0.001), 12 months (50 vs. 36%, P < 0.001), and 24 months (52 vs. 42%, P = 0.02). Self-reported oxygen use was greater in medical than in surgical subjects at 6, 12, and 24 months. Multivariate modeling of preoperative characteristics showed baseline oxygenation status was the best predictor of postoperative oxygenation.

CONCLUSIONS

LVRS increases Pa(O(2)), and decreases treadmill and self-reported use of oxygen for up to 24 months post-procedure. Clinical trial registered with www.clinicaltrials.gov (NCT 00000606).

Effects of lung volume reduction surgery for emphysema on glycolipidic hormones

BACKGROUND

Pulmonary emphysema is associated with cachexia and disregulation of the hormones regulating the glycolipid metabolism, insulin resistance, and altered substrate utilization. This study aimed at identifying the effects of lung volume reduction surgery (LVRS) on glycolipidic hormones compared to respiratory rehabilitation (RR).

METHODS

Thirty-three patients with moderate-to-severe emphysema who were undergoing video-assisted thoracoscopic LVRS were compared to 31 similar patients who refused the operation and followed a standardized RR program. All patients were evaluated before and 12 months after treatment for respiratory function, body composition, glycolipidic hormones, metabolic parameters, and insulin resistance, which was calculated using the homeostatic model assessment index for insulin resistance (HOMA-IR). These groups were compared to a matched healthy control population.

RESULTS

Only after LVRS significant improvements were obtained in respiratory function (FEV1, +25.2%; p<0.0001; residual volume, -19.5%; p<0.0001), metabolic parameters (total cholesterol, +13.1%; p<0.01; high-density lipoprotein cholesterol, +11.2%; p<0.01; triglycerides, +18.4; p<0.001; nonesterified fatty acid, -19.7%; p<0.001), and body composition (fat-free mass [FFM], +6.5%; p<0.01; fat mass [FM], +11.9%; p<0.01). The leptin/FM ratio (-6.1%; p<0.01) and resistin/FM ratio (-5.6%; p<0.01) decreased, whereas the adiponectin/FM ratio (+6.9%; p<0.01) and ghrelin (+9.2%; p<0.01) increased, together with reductions in glycemia (-8.8%; p<0.01), insulin level (-20.4%; p<0.001), and HOMA-IR (-27.2%; p<0.0001). The decrement in residual volume was correlated with increment of FFM (rho=-0.49; p<0.02), FM (rho=-0.55; p<0.009), and ghrelin (rho=-0.52; p<0.01), and also with decreases in leptin corrected for FM (rho=0.50; p<0.02) and, marginally, HOMA-IR (rho=0.35; p=0.07).

CONCLUSIONS

After LVRS, glycolipidic hormone levels and nutritional status significantly improved, along with insulin resistance reduction and more physiologic utilization of substrates. Correlations between residual volume and body composition as well as glycolipidic hormone levels suggest that postoperative recovery in respiratory dynamics may induce favorable clinical changes when compared to RR.

Update in Surgical Therapy for Chronic Obstructive Pulmonary Disease

Bullectomy for giant bullae, lung volume reduction surgery, and lung transplantation are three surgical therapies that may benefit highly selected patients with advanced chronic obstructive pulmonary disease. In this article, each procedure is reviewed, with an emphasis on guidelines for patient selection and clinical outcomes for the practicing pulmonologist. Recent results from the National Emphysema Treatment Trial, updated International Society for Heart and Lung Transplantation Registry data, and revised guidelines for patient selection for lung transplantation are discussed.

Canadian Thoracic Society recommendations for management of chronic obstructive pulmonary disease - 2007 update

Chronic obstructive pulmonary disease (COPD) is a major respiratory illness in Canada that is both preventable and treatable. Our understanding of the pathophysiology of this complex condition continues to grow and our ability to offer effective treatment to those who suffer from it has improved considerably. The purpose of the present educational initiative of the Canadian Thoracic Society (CTS) is to provide up to date information on new developments in the field so that patients with this condition will receive optimal care that is firmly based on scientific evidence. Since the previous CTS management recommendations were published in 2003, a wealth of new scientific information has become available. The implications of this new knowledge with respect to optimal clinical care have been carefully considered by the CTS Panel and the conclusions are presented in the current document. Highlights of this update include new epidemiological information on mortality and prevalence of COPD, which charts its emergence as a major health problem for women; a new section on common comorbidities in COPD; an increased emphasis on the meaningful benefits of combined pharmacological and nonpharmacological therapies; and a new discussion on the prevention of acute exacerbations. A revised stratification system for severity of airway obstruction is proposed, together with other suggestions on how best to clinically evaluate individual patients with this complex disease. The results of the largest randomized clinical trial ever undertaken in COPD have recently been published, enabling the Panel to make evidence-based recommendations on the role of modern pharmacotherapy. The Panel hopes that these new practice guidelines, which reflect a rigorous analysis of the recent literature, will assist caregivers in the diagnosis and management of this common condition.

A pilot study on the feasibility of interventional lung volume reduction

The objective of this study was to evaluate the feasibility and safety of lung volume reduction by transbronchial alcohol and lipiodol suspension infusion with the aid of balloon-tipped catheter occlusion. Twenty-six healthy adult rabbits were divided into four treatment groups: alcohol and lipiodol suspension infusion (n = 8), lipiodol infusion (n = 8), alcohol infusion (n = 5), or bronchial lumen occlusion (n = 5). After selective lobar or segmental bronchial catheterization using a balloon-tipped occlusion catheter, the corresponding drug infusion was performed. Bone cement was used to occlude the bronchial lumen in the occlusion group. The animals were followed up for 10 weeks by chest X-ray and computed tomography (CT), and then the whole lungs were harvested for histological examination. Alcohol and lipiodol suspension or lipiodol could be stably retained in alveoli in the first two groups based on chest X-ray and CT, but obvious collapse only occurred in the group receiving alcohol and lipiodol suspension or the bronchial lumen occlusion group. Histological examination revealed damage and disruption of the alveolar epithelium and fibrosis in related lung tissue in the group receiving alcohol and lipiodol suspension. Similar changes were seen in the bronchial lumen occlusion group, apart from obvious marginal emphysema of the target areas in two animals. Interstitial pneumonia and dilated alveoli existed in some tissue in target areas in the lipiodol group, in which pulmonary fibrosis obliterating alveoli also occurred. Chronic alveolitis and pleural adhesion in target areas occurred in the group infused with alcohol alone, whereas visceral pleura of the other three groups was regular and no pleural effusion or adhesion was found. Alcohol and lipiodol suspension that is stably retained in alveoli can result in significant lung volume reduction. Through alcohol and lipiodol suspension infusion, obstructive emphysema or pneumonia arising from bronchial lumen occlusion could be avoided.

Lung volume reduction surgery

Lung volume reduction surgery (LVRS) has been widely studied and has been available for the treatment of advanced emphysema for 10 years. This paper reviews some of the historical attempts at surgical treatment of emphysema, the physiology of LVRS, and the modern data on patient selection, risks, and benefits. Data from the National Emphysema Treatment Trial are presented in the context of the large body of case series and smaller randomized trials that have preceded that study. Future technologies of bronchoscopic lung volume reduction are also discussed.

A multicenter trial of an intrabronchial valve for treatment of severe emphysema

OBJECTIVES

Minimally invasive endoscopic treatment of emphysema could provide palliation with less risk than lung volume reduction surgery and offer therapy to patients currently not considered for lung volume reduction surgery. The Intrabronchial Valve is used to block bronchial airflow in the most emphysematous areas of lung.

METHODS

Patients with severe chronic obstructive pulmonary disease and heterogeneous upper lobe-predominant emphysema were eligible. Patients underwent flexible bronchoscopic placement of valves into segmental or subsegmental airways in both upper lobes. Outcomes assessed over a minimum of 6 months of follow-up included the safety, feasibility, tolerance, and success of valve placement; health-related quality of life; exercise capacity; pulmonary function; and gas exchange.

RESULTS

Five centers treated 30 patients. Patient follow-up ranged from 1 to 12 months. A mean of 6.1 valves were placed per patient. Valves were positioned by means of flexible bronchoscopy in 99% of desired airways, and the procedure duration ranged from 15 to 125 minutes (mean, 65 minutes). Hospital discharge occurred within 2 days in 27 of 30 patients. There were no deaths or episodes of valve migration, tissue erosion, or significant bleeding. Eighty-three percent of patients had no adverse events judged probably or definitely related to the device. Patients experienced significant improvement in health-related quality of life, although the physiologic and exercise outcomes did not show statistically significant improvements.

CONCLUSIONS

These first multicenter results with the Intrabronchial Valve demonstrate significant improvements in health-related quality of life and acceptable safety, ease of use, and procedural complication rates. The valve might be a safer and less-invasive alternative to surgical therapy for patients with severe emphysema.

Lung volume reduction surgery for diffuse emphysema

BACKGROUND

Lung volume reduction surgery (LVRS) has been re-introduced for treating patients with severe diffuse emphysema. It is a procedure that aims to improve long-term daily functioning, although it is costly and may also be associated with a high risk of mortality.

OBJECTIVES

To assemble evidence from randomised controlled trials for the effectiveness of LVRS, and identify optimal surgical techniques.

SEARCH STRATEGY

Randomised controlled trials were identified using the Cochrane Airways Group Chronic Obstructive Pulmonary Disease (COPD) register. Searches are current to September 2005.

SELECTION CRITERIA

Randomised controlled trials that studied the safety and efficacy of LVRS in patients with diffuse emphysema were included. Studies were excluded if they investigated giant or bullous emphysema.

DATA COLLECTION AND ANALYSIS

Two independent review authors assessed trials for inclusion and extracted data. Where possible, data from more than one study were combined using RevMan 4.2 software.

MAIN RESULTS

Eight studies (1663 participants) met the entry criteria of the review. One study accounted for 73% of the participants recruited. Study quality was high, although blinding in studies was not possible. Ninety day mortality was significantly greater in all those who underwent LVRS (odds ratio 6.57 (95% CI 3.34 to 12.95), four studies, N = 1415). A subgroup analysis by risk status suggested that there was a subgroup of participants who were consistently at a significant risk of death, although this was only measured in one large study. The ninety day mortality data indicated that death was more likely with LVRS irrespective of risk status identified in one large study. Improvements in lung function, quality of life and exercise capacity were more likely with LVRS than with usual follow-up.

AUTHORS' CONCLUSIONS

The evidence summarised in this review is drawn from one large study, and several smaller trials. The findings from the large study indicated that in patients who survive up to three months post-surgery, there were significantly better health status and lung function outcomes in favour of surgery compared with usual medical care. Patients identified post hoc as being of high risk of death from surgery were those with particularly impaired lung function and poor diffusing capacity and/or homogenous emphysema. Further research should address the effect of this intervention on exacerbations and rate of decline in lung function and health status.

Resting energy expenditure and metabolic changes after lung volume reduction surgery for emphysema

BACKGROUND

Oxygen consumption volume (VO2) and resting energy expenditure are increased in emphysema because of impaired respiratory function and mechanics, with greater oxygen cost of breathing and altered metabolism. We hypothesized that lung volume reduction surgery may improve energy expenditure and metabolism.

METHODS

In this 1-year prospective study, 30 patients with moderate-to-severe emphysema underwent bilateral lung volume reduction surgery; 28 similar patients, who refused operation, followed a standard respiratory rehabilitation program. Oxygen consumption volume and resting energy expenditure, both corrected for fat-free mass, VO2 proportion of respiratory muscles (%VO2Resp), respiratory quotient, and energy substrate oxidation were determined by using a calorimetric chamber with indirect methods.

RESULTS

Only after surgery significant improvements resulted in 1-second forced expiratory volume (+20.4%, p = 0.009), residual volume (-24.8%, p = 0.001), diffusion-lung carbon-monoxide (+18.4%, p = 0.008), body mass index (+5.5%, p = 0.01), resting energy expenditure (-8.2%, p = 0.006), and %VO2Resp (-44.1%, p = 0.0008) with increase in respiratory quotient (0.79 versus 0.84, p = 0.03) and conversion from prevalent lipid (44.6% versus 34.3%, p = 0.0007) to prevalent carbohydrate (25.2% versus 42.2%, p = 0.0006) metabolism. Thirteen operated on patients discontinued oral steroids, showing the most significant improvements. The remaining 17 experienced significant changes compared with the rehabilitation group despite oral steroids (resting energy expenditure -7.0% versus +4.1%, and %VO2Resp -34.0% versus +0.7%, p = 0.001). Decrease of resting energy expenditure and %VO2Resp correlated with reduction of residual volume (p = 0.02 and p = 0.001) and increment of body mass index (p = 0.03 and p = 0.004).

CONCLUSIONS

Lung volume reduction surgery significantly decreased %VO2Resp and resting energy expenditure over respiratory rehabilitation and despite oral steroid therapy. Substrate oxidation changed from prevalent lipid to prevalent carbohydrate. Correlations with residual volume and nutritional status suggest that restoration of respiratory mechanics reduces energy expenditure and approximates metabolism to normal.

A randomized clinical trial of lung volume reduction surgery versus best medical care for patients with advanced emphysema: a two-year study from Canada

BACKGROUND

We present a summary report evaluating the efficacy of lung volume reduction surgery (LVRS) in patients with advanced emphysema in the Canadian setting.

METHODS

Quality of Life measures assessed the efficacy of adding LVRS to best medical care including rehabilitation in this blinded randomized multicentered controlled trial with 2 years of follow-up. Health utility and quality-adjusted life years (QALY) were outcomes central to our economic assessment.

RESULTS

None of the 32 patients randomized to the LVRS arm or 30 patients in the best medical care (BMC) arm crossed-over and no patients were lost to follow-up. Overall surgical mortality was 16% at 2 years while the overall medical mortality was 13% (p = 0.914). There were no 30-day postoperative deaths but 2 deaths (6%) occurred within 90 days of randomization. Surgery reduced the residual volume measured at 6 months by 23% (5,385 mL to 4,322 mL, p = 0.007). There was an increase in forced expiratory volume in 1 second (FEV1) of 30% (265 mL, p = 0.013) from baseline, an improvement in the six minute walk test (6MWT) of 78 meters (p = 0.045), and an increase in Health Utility Index 3 (HUI3) which peaked at 6 months with a difference of 0.16 (p = 0.129). There was a gain in QALYs of 0.21 (p = 0.19) in the LVRS-arm over the BMC-arm. The LVRS costs an additional 28,119 Canadian dollars (CAD) compared with BMC or 133,900 CAD/QALY gained.

CONCLUSIONS

The addition of LVRS to best medical care including pulmonary rehabilitation improves pulmonary function, exercise activity, and quality of life in selected patients with advanced emphysema. Cost is high but in keeping with other treatment modalities currently available.

Long-term follow-up of patients receiving lung-volume-reduction surgery versus medical therapy for severe emphysema by the National Emphysema Treatment Trial Research Group

BACKGROUND

The National Emphysema Treatment Trial defined subgroups of patients with severe emphysema in whom lung-volume-reduction surgery (LVRS) improved survival and function at 2 years. Two additional years of follow-up provide valuable information regarding durability.

METHODS

A total of 1218 patients with severe emphysema were randomized to receive LVRS or medical treatment. We present updated analyses (4.3 versus 2.4 years median follow-up), including 40% more patients with functional measures 2 years after randomization.

RESULTS

The intention-to-treat analysis of 1218 randomized patients demonstrates an overall survival advantage for LVRS, with a 5-year risk ratio (RR) for death of 0.86 (p = 0.02). Improvement was more likely in the LVRS than in the medical group for maximal exercise through 3 years and for health-related quality of life (St. George's Respiratory Questionnaire [SGRQ]) through 4 years. Updated comparisons of survival and functional improvement were consistent with initial results for four clinical subgroups of non-high-risk patients defined by upper-lobe predominance and exercise capacity. After LVRS, the upper-lobe patients with low exercise capacity demonstrated improved survival (5-year RR, 0.67; p = 0.003), exercise throughout 3 years (p < 0.001), and symptoms (SGRQ) through 5 years (p < 0.001 years 1 to 3, p = 0.01 year 5). Upper-lobe-predominant and high-exercise-capacity LVRS patients obtained no survival advantage but were likely to improve exercise capacity (p < 0.01 years 1 to 3) and SGRQ (p < 0.01 years 1 to 4).

CONCLUSIONS

Effects of LVRS are durable, and it can be recommended for upper-lobe-predominant emphysema patients with low exercise capacity and should be considered for palliation in patients with upper-lobe emphysema and high exercise capacity.

Lung-Volume Reduction Surgery as an Alternative or Bridging Procedure to Lung Transplantation

BACKGROUND

In this study, we prospectively analyzed the functional outcome and the survival after lung-volume reduction surgery (LVRS) in patients with end-stage emphysema who were initially potential candidates for lung transplantation (LTX), and investigated the impact of LVRS on posttransplant course in patients who underwent LTX after LVRS.

METHODS

Of the 216 patients who underwent LVRS between 1994 and 2005, 58 were potential candidates for LTX at the time of LVRS (age 65 years or younger, forced expiratory volume in 1 second 25% of predicted or less; LVRS/LTX group). Lung-volume reduction surgery was performed by means of video-assisted, bilateral stapled resection of target areas. During the same period, 31 patients underwent primary LTX for end-stage emphysema (LTX group). Spirometry, plethysmography, carbon monoxide diffusing capacity, 6-minute walking distance, and dyspnea score were assessed preoperatively and at predetermined times after operation. Survival analysis was performed by use of the Kaplan-Meier method.

RESULTS

All the functional variables significantly improved after LVRS and peaked within the first year. Subjective improvement was observed for up to 5 years after LVRS, and 53% (31 of 58) of the patients were still alive and had not undergone transplantation after a median follow-up of 44 months. Fourteen percent (8 of 58) of the patients underwent secondary LTX because of progressive worsening of the respiratory function after a median bridging time between LVRS and LTX of 33 months. Postoperative recovery after transplantation and median survival time were comparable between the 8 patients of the LVRS/LTX group and the 31 patients of the LTX group (96.5 months versus 118.5 months, p = 0.9).

CONCLUSIONS

Lung-volume reduction surgery can significantly improve symptoms and lung function in selected patients who are initially potential candidates for LTX. Lung-volume reduction surgery can allow the postponement of LTX for up to 4 to 5 years and does not impair the chances for a subsequent successful LTX.

Lung volume reduction surgery for emphysema: What the radiologist needs to know

Imaging plays a pivotal role in the selection of patients for the surgical treatment of emphysema. In this article, the imaging features of emphysema are reviewed along with the surgical options for treatment. Particular emphasis is given to lung volume reduction surgery as this technique has gained wide acceptance within the thoracic surgical community in recent years. Radiologists need to have an understanding of which patients may be potentially suitable for this technique.

Awake nonresectional lung volume reduction surgery

OBJECTIVE

To assess the feasibility, safety, and early results of awake lung volume reduction surgery (LVRS) performed under thoracic epidural anesthesia by a new nonresectional technique.

SUMMARY BACKGROUND DATA

So far, resectional LVRS under general anesthesia and one-lung ventilation is the more frequently used technique, but procedure-related morbidity has been considerable.

METHODS

The study cohort included 12 patients undergoing unilateral awake LVRS. Evaluated parameters included technical feasibility and anesthesia satisfaction scored into 4 grades (from 1 = poor to 4 = excellent), global operating room time, and arterial carbon dioxide tension (PaCO2). In addition, 6-month changes in outcome measures, including forced expiratory volume in 1 second (FEV1), residual volume (RV), 6-minute walking test (SMWT), and dyspnea index were recorded. Perioperative and 6-month results were comparable with those of a control group undergoing unilateral resectional LVRS.

RESULTS

Technical feasibility was excellent to satisfactory in 11 patients. One patient required conversion to one-lung ventilation. Differences between the awake and control group included global operating room time (90 +/- 17 minutes versus 145 +/- 19 minutes, P < 0.00001); PaCO2 24 hours after surgery (45 +/- 6 mm Hg versus 49 +/- 6 mm Hg, P = 0.02); and hospital stay (7.8 +/- 5 days versus 11.7 +/- 4 days, P = 0.02). Significant (P < 0.002) improvements occurred at 6 months in FEV1 (0.31 +/- 0.17 L), RV (-1.41 +/- 0.7 L), SMWT (73 +/- 25 m), and dyspnea index (-1.3 +/- 0.5) and were comparable with those of the control group.

CONCLUSIONS

In this study, awake nonresectional LVRS proved feasible and safe. This new modality was associated with a faster recovery and satisfactory 6-month outcome, which did not differ from that of resectional LVRS.

Comparison of lung volume reduction surgery and physical training on health status and physiologic outcomes: a randomized controlled clinical trial

STUDY OBJECTIVES

In 1996, researchers in Sweden initiated a collaborative randomized study comparing lung volume reduction surgery (LVRS) and physical training with physical training alone. The primary end point was health status; secondary end points included survival and physiologic measurements.

DESIGN

After an initial 6-week physical training program, researchers' patients were randomized to either LVRS (surgical group [SG]) with continued training for 3 months, or to continued training alone (training group [TG]) for 1 year.

SETTING

All seven thoracic surgery centers in Sweden.

PATIENTS

All patients in Sweden with severe emphysema fulfilling inclusion criteria for LVRS.

INTERVENTIONS

Patients randomized to surgery underwent a median sternotomy, except for a few patients in whom thoracotomy or video-assisted thoracoscopy were performed. In the TG, supervised physical training continued for 1 year; in the SG, supervised physical training continued for 3 months postoperatively.

MEASUREMENTS AND RESULTS

Fifty-three patients were included in each group. Six in-hospital deaths occurred after surgery (12%), and one more death occurred during follow-up. Two deaths occurred in the TG. The difference in death rates between the groups was not statistically significant. Health status, as measured by St. George Respiratory Questionnaire (SGRQ) [total scale score mean difference at 1 year, 14.7; 95% confidence interval (CI), 9.8 to 19.7] as well as by the Medical Outcomes Study Short-Form General Health Survey (physical function scale score mean difference at 1 year, 19.7; 95% CI, 12.1 to 27.3) was improved from baseline in the SG compared with the TG. FEV(1), residual volume, and shuttle walking test values also improved in the SG but not in the TG after 6 months and 12 months.

CONCLUSIONS

In severe emphysema, LVRS can improve health status in survivors but is associated with mortality risk. The effects are stable for at least 1 year. Physical training alone failed to achieve a similar improvement.

Effects of lung volume reduction surgery on distribution of ventilation and perfusion

Lung volume reduction surgery (LVRS) results in functional improvements in most patients. The mechanisms behind the improvements are not clear. We hypothesized that reduced inequalities in ventilation to perfusion ratio (V/Q) may be a contributing explanation. Nine patients who underwent LVRS were investigated by ventilation and perfusion scintigrams before and after surgery. In addition, 8 healthy subjects were investigated once. The relative ventilation, perfusion and V/Q were calculated in 1 x 1 cm lung elements. Normal range of the element count-rate was determined by the corresponding results in the normal subjects. Results of this small study show a significant effect of LVRS on V/Q, with reduction of shunt-like elements. We conclude that the functional improvement after LVRS to some extent may be explained by decreased V/Q inequality.

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.

[VENT: International study of bronchoscopic lung volume reduction as a palliative treatment for emphysema]

BACKGROUND

Therapeutic options for patients with severe emphysema remain limited. In selected patients, lung volume reduction surgery has been shown to improve pulmonary function, exercise capacity, quality of life and also survival. The technique of inserting one-way valves endoscopically into the airways supplying the most affected areas of lung provides the possibility of achieving similar results to surgery (i.e. volume reduction) in a less invasive way, which is also reversible, since the valves can be removed at any time. This technique has been shown to be safe. The aim of this study is to evaluate the efficacy of this technique compared to optimal medical therapy in patients with heterogeneous emphysema defined according to radiological criteria.

METHODS

A prospective, international, multicentre (20 centres) randomised trial is underway to establish the efficacy and safety of endobronchial valve placement in this patient group. This study will enrol 270 patients and be analysed on an intention to treat basis. Patients are randomised either to valve insertion or optimal medical treatment alone in a ratio of 2 to 1. Follow up will be ensured for at least one year.

EXPECTED RESULTS

The two principal outcome measures will be improvement at six months in FEV1 and in six minute walk distance. The safety of the technique will be evaluated over the same period. Details of the study are available online for patients and their physicians at www.euroemphysema.com.

Model-based versus clinical prediction of the spirometric response to lung volume reduction surgery

BACKGROUND

Lung volume reduction surgery (LVRS) improves symptoms and lung function in selected patients with severe emphysema.

OBJECTIVES

We investigated whether models based on physiologic and radiologic predictors discriminated patients with a favorable from those with a poor spirometric response to LVRS.

METHODS

Data of a derivation cohort of 70 patients who had previously undergone LVRS served to develop two types of prediction models, lookup functions and logistic regression equations. Presence or absence of improvement in forced expiratory volume in 1 s (FEV1) > or =300 ml and forced vital capacity (FVC) > or =500 ml represented dichotomous outcomes. The residual volume/total lung capacity ratio, CT-radiological emphysema heterogeneity scores and diffusing capacity, a marker of emphysema severity, were the predictors. Models were used to predict spirometric outcomes for a validation cohort of 60 emphysema patients referred for LVRS. Furthermore, the surgeon preoperatively estimated outcomes based on all available clinical data but blinded to model predictions. Spirometric changes within 6 months following surgery were compared to predictions.

RESULTS

Median FEV1 in the validation cohort increased from 0.69 to 1.00 liters (+41%), and FVC from 2.07 to 2.78 liters (+29%; p < 0.05 for changes). Lookup functions and logistic regression equations identified patients experiencing major increases in FEV1 > or =300 ml and FVC > or =500 ml with an accuracy quantified by areas under the receiver-operating characteristic curves of 0.72 to 0.76 (all areas >0.5, p < 0.05). Predictions by the surgeon had an accuracy of 0.71 to 0.78 (p = NS vs. models).

CONCLUSIONS

The accuracy of models based on three predictors was fair and similar to assessment by an experienced surgeon based on all available clinical information. Prediction models may contribute to the consistent assessment of LVRS candidates.

Results of unilateral lung volume reduction surgery in patients with distinct heterogeneity of emphysema between lungs

OBJECTIVE

This study was undertaken to analyze the comprehensive outcome of unilateral lung volume reduction in patients with distinct heterogeneity of emphysema between lungs assessed by a visual radiologic scoring system.

METHODS

Ninety-seven patients who underwent intentional unilateral lung volume reduction because of distinct heterogeneity of emphysema between lungs (asymmetric ratio of emphysema >/=1.1) between 1995 and 2003 were evaluated. Baseline median measures were 0.83 L for forced expiratory volume in 1 second, 5.0 L for residual volume, 380 m for 6-minute walking test distance, 0.50 for maximal incremental treadmill test score, and 25 for physical functioning domain score assessed by the Short Form-36 Quality of Life questionnaire.

RESULTS

Median follow-up was 34 months. Significant improvements occurred for as long as 36 months in forced expiratory volume in 1 second (+24%), residual volume (-12%), Short Form-36 Quality of Life questionnaire physical functioning domain score (+100%), 6-minute walking test distance (+18%), and maximal incremental treadmill test score (+200%). A direct correlation was found between asymmetric ratio of emphysema and change in forced expiratory volume in 1 second ( r = 0.65, P < .00001). At 60 months, residual volume (-6.2%), maximal incremental treadmill test score (+100%), and Short Form-36 Quality of Life questionnaire physical functioning domain score (+70%) were still significantly improved. Five-year survival was 82%; 5-year freedom from contralateral lung volume reduction was 70%.

CONCLUSIONS

In this series, significant, long-lasting improvements and satisfactory survival were seen after intentional unilateral lung volume reduction. Heterogeneity of emphysema between lungs was directly correlated with improvement at 36 months in forced expiratory volume in 1 second. Our results suggest that unilateral lung volume reduction is a suitable option for patients with distinct heterogeneity of emphysema between lungs.