Undergoing Lung Volume Reduction Surgery Research Articles

EFFICACY OF AN IMPLANTABLE VALVE FOR TREATMENT OF ALVEOLOPLEURAL FISTULAS WITH PROLONGED AIR LEAKS

EFFICACY OF AN IMPLANTABLE VALVE FOR TREATMENT OF ALVEOLOPLEURAL FISTULAS WITH PROLONGED AIR LEAKS

TENSION PNEUMOTHROAX AS INITIAL MANIFESTATION OF LUNG INVOLVEMENT IN CUTANEOUS SARCOIDOSIS

TOPIC: Lung Pathology TYPE: Medical Student/Resident Case Reports INTRODUCTION: Bullae formation resulting in pneumothorax typically occurs in the late stages of pulmonary sarcoidosis. CASE PRESENTATION: A 56-year-old female with past medical history of hypertension and cutaneous sarcoidosis diagnosed two years ago via skin biopsy. The patient presented with symptoms of heaviness on the right side on the chest, cough, and shortness of breath which started the day before. On examination, the patient was tachypneic, tachycardiac with decreased breath sounds on the right upper and middle lung fields. Chest x-ray showed a right-sided pneumothorax (Figure #1). Computed tomography of the chest (CT) showed a large right pneumothorax measuring approximately 7.5 cm between the visceral and parietal pleura. There were also multiple right upper lobe pulmonary micronodules and biapical bullae, worse on the right lung (figure #2). A Chest tube thoracostomy was performed and patient monitored in the ICU till pneumothorax resolved. Following resolution, a video-assisted thoracoscopic surgery (VATS) with right apical wedge resection of blebs, mechanical and chemical pleurodesis, and chest tube placement was performed. Histology of the right lung apex confirmed non-necrotizing granulomatous reaction from sarcoidosis. The patient improved following surgery and discharged with outpatient follow-up. DISCUSSION: Bullae formation typically presents in advanced pulmonary sarcoidosis with fibrotic changes. In rare cases, bullous disease and subsequent pneumothorax have been reported in the early stage of pulmonary sarcoidosis [1]. Several mechanisms have been proposed for the formation of such bullae; these include bronchial obstruction by sarcoid lesions, causing peripheral air trapping and alveolar distension and rupture, retraction and collapse of surrounding disease lung, and the presence of inflammatory alveolitis causing tissue destruction [2]. Pneumothorax is caused by rupture of these subpleural bullae or necrotic granulomas. Management is by chest tube drainage, bullectomy by thoracoscopic surgery may be required in cases of recurrent pneumothorax [3]. A high index of suspicion should be maintained as pneumothorax can be the presenting feature of early or advanced pulmonary sarcoidosis and predisposes to increased morbidity and mortality. CONCLUSIONS: Bullous disease and pneumothorax are rare presentations of sarcoidosis. Pneumothorax should be suspected in all stages of sarcoidosis in patients with pulmonary symptoms due to high mortality associated with late detection and management. REFERENCE #1: Froudarakis, Marios E., et al. "Pneumothorax as a first manifestation of sarcoidosis." Chest 112.1 (1997): 278-280. REFERENCE #2: Manika, Katerina, et al. "Pneumothorax in sarcoidosis." Journal of thoracic disease 6.Suppl 4 (2014): S466. REFERENCE #3: Keller, Cesar A., et al. "Histopathologic diagnosis made in lung tissue resected from patients with severe emphysema undergoing lung volume reduction surgery." Chest 111.4 (1997): 941-947. DISCLOSURES: No relevant relationships by Ramez Alyacoub, source=Web Response No relevant relationships by Ifunanya Ejikeme, source=Web Response No relevant relationships by CHIDINMA EJIKEME, source=Web Response

Analysis of lung volume reduction surgery results with video-assisted thoracoscopic surgery in emphysematous lung patients.

AimIn our study, we aimed to evaluate the results of patients who underwent lung volume reduction surgery with video-assisted thoracoscopic surgery due to diffuse or upper lobe limited emphysema.Material and methodsPatients who underwent lung volume reduction surgery (LVRS) for emphysema in our clinic between March 2015 and January 2020 were included in the study. The files of the patients were evaluated retrospectively. Age, gender, smoking history, hospitalization time, drain removal time, complications, and postoperative pulmonary function test values were evaluated in the patient records.ResultsTwenty-four of the patients were male and 2 were female. The average age was determined as 49.6. Twenty-six patients underwent 31 surgical procedures, 5 of which were bilateral. Twenty-seven of them were performed by videothoracoscopic LVRS. Preoperative mean forced expiratory volume in 1 s (FEV1) value was 32.7%, total lung capacity 132%, residual volume 280%. The average length of hospital stay was found to be 7.75 days (4–19), and the time to remove the thorax drain was 9.5 (4–23) days. FEV1: 1.78 (48.5%) was found in the pulmonary function tests of the patients at the 6th month postoperative controls. According to preoperative FEV1, 48.3% improvement was detected.ConclusionsVolume reduction surgery is a treatment method that positively affects the natural course of emphysema in addition to quitting smoking and oxygen therapy. Patients with predominantly emphysema in the upper lobes, low exercise capacity, and appropriate FEV1 values benefited most from this treatment.

Applicability of color-coded computed tomography images in lung volume reduction surgery planning.

Adequate patient selection is the key to successful lung volume reduction in patients with pulmonary emphysema. Computed tomography (CT) enables a reliable detection of pulmonary emphysema and allows an accurate quantification of the severity. Our goal was to investigate the usefulness and reliability of color-coded (CC) CT images in classification of emphysema and preoperative lung volume reduction planning. Fifty patients undergoing lung volume reduction surgery at our institution between September 2015 and February 2016 were retrospectively investigated. Three readers visually assessed the amount and distribution patterns of pulmonary emphysema on axial, multi-planar and CC CT images using the Goddard scoring system and a surgically oriented grading system (bilateral markedly heterogenous, bilateral intermediately heterogenous, bilateral homogenous and unilateral heterogenous emphysema). Observer dependency was investigated by using Fleiss' kappa (κ) and the intraclass correlation coefficient (ICC). Results were compared to quantitative results from densitometry measurements and lung perfusion scintigraphy by using Spearman correlation. Recommendations for lung volume reduction sites based on emphysema amount and distribution of all readers were compared to removal sites from the surgical reports. Inter-rater agreement for emphysema distribution rating was substantial for CC images (κ=0.70; 95% CI, 0.64-0.80) and significantly better compared to axial and multiplanar images (P≤0.001). The inter-rater agreement for recommended segment removal was moderate for CC images (κ=0.56; 95% CI, 0.49-0.63) and significantly better compared to axial and multiplanar images (P<0.001). Visual emphysema rating correlated significantly with measurements from densitometry and perfusion scintigraphy in the upper and lower lung zones in all image types. CC CT images allow a precise, less observer-dependent evaluation of distribution of pulmonary emphysema and resection recommendation compared to axial and multiplanar CT images and might therefore be useful in lung volume resection surgery planning.

Patient experience of lung volume reduction procedures for emphysema: a qualitative service improvement project.

The aim of this service improvement project was to gain understanding of the patient experience of lung volume reduction surgery (LVRS) and endobronchial valve (EBV) placement, from referral through to post-discharge care.Focus group interviews were carried out in two tertiary centres in London and Leicester, UK. Sixteen patients who had undergone lung volume reduction surgery (LVRS), endobronchial valve (EBV) placement, or both, were recruited. Prior to participation in each focus group, participants completed a questionnaire to guide and focus discussion. Thematic analysis identified common themes to the participant experience of receiving lung volume reduction interventions.Themes included patient focus on declining health and the need to “fight” for a referral; consequences of having procedures and potential unexpected complications; and vulnerability post discharge and limited continuity of care. Participants were clear that the benefits of having had either LVRS or EBV procedures outweighed any difficulties experienced. Participants were keen to have further similar interventions if appropriate.These data confirm the need to develop more systematic lung volume reduction pathways, provide appropriate information, and ensure that post-discharge care is optimal.

Individualised risk in patients undergoing lung volume reduction surgery: the Glenfield BFG score

Lung volume reduction surgery (LVRS) has been shown to be beneficial in patients with chronic obstructive pulmonary disease, but there is low uptake, partly due to perceived concerns of high operative mortality. We aimed to develop an individualised risk score following LVRS.This was a cohort study of patients undergoing LVRS. Factors independently predicting 90-day mortality and a risk prediction score were identified. Reliability of the score was tested using area under the receiver operating characteristic curve (AUROC).237 LVRS procedures were performed. The multivariate analysis factors associated independently with death were: body mass index (BMI)<18.5 kg·m-2 (OR 2.83, p=0.059), forced expiratory volume in 1 s (FEV1)<0.71 L (OR 5.47, p=0.011) and transfer factor of the lung for carbon monoxide (TLCO) <20% (OR 5.56, p=0.031). A risk score was calculated and total score assigned. AUROC for the risk score was 0.80 and a better predictor than individual components (p<0.01). The score was stratified into three risk groups. Of the total patients, 46% were classified as low risk. Similar improvements in lung function and health status were seen in all groups. The score was introduced and tested in a further 71 patients. AUROC for 90-day mortality in this cohort was 0.84.It is possible to provide an individualised predictive risk score for LVRS, which may aid decision making for both clinicians and patients.

Status of and prospects for bronchoscopic lung volume reduction for patients with severe emphysema.

Bronchoscopic lung volume reduction (BLVR) is a minimally invasive treatment for severe emphysema, providing treatment options for patients who are unable to undergo lung volume reduction surgery (LVRS) or lung transplantation. Current BLVR techniques include bronchoscopic volume reduction with valve implants, use of a lung volume reduction coil (LVRC), bronchoscopic thermal vapor ablation (BTVA), biological lung volume reduction (BioLVR), and use of airway bypass stents (ABS). To date, several randomized controlled trials of these bronchoscopic therapies have been conducted in patients with emphysema, and bronchoscopic volume reduction with valve implants remains the best approach thus far. Recent studies indicate that BLVR may be of great value in improving lung function, exercise capacity, and quality of life and that BLVR has the potential to replace conventional surgery for patients with severe emphysema. Optimal patient selection and the proper selection of the BLVR technique in accordance with patient characteristics are crucial to the success of BLVR. More multicenter, prospective, randomized controlled trials need to be conducted in the future to optimize the current selection strategy and evaluate the safety, efficiency, and long-term benefit of BLVR techniques.

Short- and Long-Term Effects of Ambient Ozone and Fine Particulate Matter on the Respiratory Health of Chronic Obstructive Pulmonary Disease Subjects

To date, no study has evaluated the short- and long-term effects air pollution exposure on emphysematous subjects who have undergone lung volume reduction surgery (LVRS). Data from the National Emphysema Treatment Trial study (1998–2003) included 1,218 subjects, aged 39 to 84. Daily values of ambient fine particulate matter (aerodynamic diameter < 2.5 μm; PM2.5) and ozone were obtained. Mixed-effects models tested the association between short- and long-term pollutant concentrations and changes in pulmonary function. Cumulative air pollution exposure was strongly associated with worsened respiratory function and symptoms. Mean PM2.5 was associated with poorer lung function. Lagged exposures were poorly associated with respiratory health outcomes. There were detrimental respiratory and pulmonary effects observed in response to even low levels of ambient air pollutants among study participants. These results are indicative that exposures even below those of air quality standards may still pose significant risks to severe chronic obstructive pulmonary disease (COPD) subjects.

Lung volume reduction surgery since the National Emphysema Treatment Trial: Study of Society of Thoracic Surgeons Database

The National Emphysema Treatment Trial demonstrated that lung volume reduction surgery is an effective treatment for emphysema in select patients. With chronic lower respiratory disease being the third leading cause of death in the United States, this study sought to assess practice patterns and outcomes for lung volume reduction surgery on a national level since the National Emphysema Treatment Trial. Aggregate statistics on lung volume reduction surgery reported in the Society of Thoracic Surgeons Database from January 2003 to June 2011 were analyzed to assess procedure volume, preoperative and operative characteristics, and outcomes. Comparisons with published data from the National Emphysema Treatment Trial were made using chi-square and 2-sided t tests. In 8.5 years, 538 patients underwent lung volume reduction surgery, with 20 to 118 cases reported in the Society of Thoracic Surgeons Database per year. When compared with subjects in the National Emphysema Treatment Trial, subjects in the Society of Thoracic Surgeons Database were younger (P < .001), a larger proportion underwent the procedure thoracoscopically (P < .001), and forced expiratory volume in 1 second was 31% versus 28% of predicted (P < .001). When mortality was compared between subjects in the Society of Thoracic Surgeons Database and all subjects in the National Emphysema Treatment Trial randomized to surgery, there were no significant differences. However, mortality was 3% higher in subjects in the Society of Thoracic Surgeons Database when compared with the non-high-risk National Emphysema Treatment Trial subset (P = .005). This study demonstrates the importance of patient selection and the need to develop consensus on appropriate benchmarks for mortality rates after lung volume reduction surgery. It underscores the need for dedicated centers to increasingly address the heavy burden of chronic lower respiratory disease in the United States in a multidisciplinary fashion, particularly for preoperative evaluation and postoperative management of emphysema.

Inspiratory and expiratory computed tomographic volumetry for lung volume reduction surgery

Three-dimensional (3D) computed tomographic (CT) volumetry has been introduced into the field of thoracic surgery, and a combination of inspiratory and expiratory 3D-CT volumetry provides useful data on regional pulmonary function as well as the volume of individual lung lobes. We report herein a case of a 62-year-old man with severe emphysema who had undergone lung volume reduction surgery (LVRS) to assess this technique as a tool for the evaluation of regional lung function and volume before and after LVRS. His postoperative pulmonary function was maintained in good condition despite a gradual slight decrease 2 years after LVRS. This trend was also confirmed by a combination of inspiratory and expiratory 3D-CT volumetry. We confirm that a combination of inspiratory and expiratory 3D-CT volumetry might be effective for the preoperative assessment of LVRS in order to determine the amount of lung tissue to be resected as well as for postoperative evaluation. This novel technique could, therefore, be used more widely to assess local lung function.

Distinct Responses to Hypoxia in Subpopulations of Distal Pulmonary Artery Cells Contribute to Pulmonary Vascular Remodeling in Emphysema

We have shown previously that hypoxia inhibits the growth of distal human pulmonary artery smooth muscle cells (PASMC) isolated under standard normoxic conditions (PASMCnorm). By contrast, a subpopulation of PASMC, isolated through survival selection under hypoxia was found to proliferate in response to hypoxia (PASMChyp). We sought to investigate the role of hypoxia-inducible factor (HIF) in these differential responses and to assess the relationship between HIF, proliferation, apoptosis, and pulmonary vascular remodeling in emphysema. PASMC were derived from lobar resections for lung cancer. Hypoxia induced apoptosis in PASMCnorm (as assessed by TUNEL) and mRNA expression of Bax and Bcl-2, and induced proliferation in PASMChyp (as assessed by 3H-thymidine incorporation). Both observations were mimicked by dimethyloxallyl glycine, a prolyl-hydroxylase inhibitor used to stabilize HIF under normoxia. Pulmonary vascular remodeling was graded in lung samples taken from patients undergoing lung volume reduction surgery for severe heterogenous emphysema. Carbonic anhydrase IX expression in the medial compartment was used as a surrogate of medial hypoxia and HIF stabilization and increased with increasing vascular remodeling. In addition, a mixture of proliferation, assessed by proliferating-cell nuclear antigen, and apoptosis, assessed by active caspase 3 staining, were both higher in more severely remodeled vessels. Hypoxia drives apoptosis and proliferation via HIF in distinct subpopulations of distal PASMC. These differential responses may be important in the pulmonary vascular remodeling seen in emphysema and further support the key role of HIF in hypoxic pulmonary hypertension.

Lung volume reduction surgery for native lung hyperinflation following single-lung transplantation for emphysema: which patients?

Lung transplantation is an established treatment for patients with advanced emphysema. Double-lung transplantation is favoured to avoid complications following single-lung transplantation, including native lung hyperinflation. Nonetheless, single-lung transplantation continues due to limited donor organ availability. The aim of this study was to evaluate the pre-operative assessment, surgical techniques and outcomes in patients undergoing lung volume reduction surgery for native lung hyperinflation. Eight patients underwent lung volume reduction surgery for native lung hyperinflation between October 2008 and April 2011. Symptoms, pre-operative evaluation, peri-operative morbidity, length of stay, pulmonary function and survival were examined. The mean follow-up was 17 months. Participants underwent high resolution CT and bronchoscopy with transbronchial biopsy and bronchial washings to exclude alternative causes for deterioration in pulmonary function tests. V/Q scan was performed to assess the contribution of each lung to overall function. Measurement of inspiratory airflow resistance in each lung was performed in one case. Seven patients underwent multiple wedge resections and one underwent bilobectomy. All patients survived to hospital discharge, and mean length of stay was 13.9 days. Functional improvement was demonstrated in all cases at follow-up, with a mean percentage increase of 29.3% in forced expiratory volume in one second and 21.6% in forced vital capacity. Symptomatic improvement was also reported by all patients post-operatively. Lung volume reduction surgery for native lung hyperinflation is an effective treatment strategy with an acceptable level of surgical risk. Patient selection, however, remains vital. The non-anatomical multiple wedge excision technique used here was as effective as anatomical lung volume reduction surgery used in other series. With regard to pre-operative assessment, the measurement of single-lung inspiratory airflow resistance is of particular interest. We feel that this may provide an additional method of differentiating between native lung hyperinflation and obliterative bronchiolitis prior to surgery, thus improving patient selection.

Perioperative Short-term Pulmonary Rehabilitation for Patients Undergoing Lung Volume Reduction Surgery

Although pulmonary rehabilitation is recommended for patients undergoing lung volume reduction surgery, the optimal method of pulmonary rehabilitation is unclear. The aim of this study was to determine the feasibility and safety of perioperative short-term pulmonary rehabilitation. We enrolled candidates for lung volume reduction surgery from 1999 to 2006 and retrospectively evaluated the feasibility and safety of perioperative short-term pulmonary rehabilitation for these patients. The program included the progressive exercise training on a treadmill for approximately 3 weeks. Two primary endpoints, feasibility and safety, were determined by the adherence rates of the program session and the adverse events. Pulmonary function and exercise capacity were evaluated at baseline and the termination of pre- and postoperative short-term pulmonary rehabilitation. Twenty-two patients were enrolled in this study. All patients completed our program without any serious adverse events. The mean values of adherence rates of the preoperative, postoperative, and overall period were, 89.1%, 95.1%, and 92.1%, respectively. All values of pulmonary function tests, except for forced vital capacity, significantly improved at the termination of postoperative short-term pulmonary rehabilitation in comparison to those at the termination of preoperative short-term pulmonary rehabilitation. The values of the 6-minute walk distance, total exercise time, and maximal workload on incremental exercise test were significantly improved by preoperative short-term pulmonary rehabilitation, and their values were maintained until the termination of postoperative short-term pulmonary rehabilitation. The results indicated that it is both feasible and safe to perform perioperative short-term pulmonary rehabilitation.

Long-term follow-up after bronchoscopic lung volume reduction in patients with emphysema

Bronchoscopic lung volume reduction (BLVR) is a novel emphysema therapy. We evaluated long-term outcome in patients with heterogeneous emphysema undergoing BLVR with one-way valves. 40 patients undergoing unilateral BLVR entered our study. Pre-operative mean forced expiratory volume in 1 s (FEV(1)) was 0.88 L · s(-1) (23%), total lung capacity was 7.45 L (121%), intrathoracic gas volume was 6 L (174%), residual volume (RV) was 5.2 L (232%), and the 6-min walk test (6MWT) was 286 m. All patients required supplemental oxygen; the Medical Research Council (MRC) dyspnoea score was 3.9. High-resolution computed tomography (HRCT) results were reviewed to assess the presence of interlobar fissures. 33 patients had a follow-up of >12 months (median 32 months). 37.5% of the patients had visible interlobar fissures. 40% of the patients died during follow-up. Three patients were transplanted and one underwent lung volume reduction surgery. Supplemental oxygen, FEV(1), RV, 6MWT and MRC score showed a statistically significant improvement (p ≤ 0.0001, p = 0.004, p = 0.03, p = 0.003 and p<0.0001, respectively). Patients with visible fissures had a functional advantage. BLVR is feasible and safe. Long-term sustained improvements can be achieved. HRCT-visible interlobar fissures are a favourable prognostic factor.

Lung volume reduction surgery: nonpharmacological approach

To revise the current nonpharmacologic methods used in the care of patients undergoing lung volume reduction surgery (LVRS). A recent report of the unquestionable palliative role of LVRS awakened a renewed interest in the procedure as a valid treatment alternative in selected patients with severe emphysema. A detailed description of the foundations of the approach to patients undergoing LVRS is described to provide guidance for daily practice.

Trapped wind: A retrospective review of patients undergoing lung volume reduction surgery

Trapped wind: A retrospective review of patients undergoing lung volume reduction surgery

National Emphysema Treatment Trial redux: Accentuating the positive

Under the Freedom of Information Act, we obtained the follow-up data of the National Emphysema Treatment Trial (NETT) to determine the long-term outcome for "a heterogeneous distribution of emphysema with upper lobe predominance," postulated by the NETT hypothesis to be optimal candidates for lung volume reduction surgery. Using the NETT database, we identified patients with heterogeneous distribution of emphysema with upper lobe predominance and analyzed for the first time follow-up data for those receiving lung volume reduction surgery and those receiving medical management. Furthermore, we compared the results of the NETT reduction surgery group with a previously reported consecutive case series of 250 patients undergoing bilateral lung volume reduction surgery using similar selection criteria. Of the 1218 patients enrolled, 511 (42%) conformed to the NETT hypothesis selection criteria and received the randomly assigned surgical or medical treatment (surgical = 261; medical = 250). Lung volume reduction surgery resulted in a 5-year survival benefit (70% vs 60%; P = .02). Results at 3 years compared with baseline data favored surgical reduction in terms of residual volume reduction (25% vs 2%; P < .001), University of California San Diego dyspnea score (16 vs 0 points; P < .001), and improved St George Respiratory Questionnaire quality of life score (12 points vs 0 points; P < .001). For the 513 patients with a homogeneous pattern of emphysema randomized to surgical or medical treatment, lung volume reduction surgery produced no survival advantage and very limited functional benefit. Patients most likely to benefit from lung volume reduction surgery have heterogeneously distributed emphysema involving the upper lung zones predominantly. Such patients in the NETT trial had results nearly identical to those previously reported in a nonrandomized series of similar patients undergoing lung volume reduction surgery.

Small Airway Pathology and Bronchoreversibility in Advanced Emphysema

ABSTRACTBackground: Poorly reversible airflow obstruction is a hallmark feature of chronic obstructive pulmonary disease (COPD). However, some COPD patients demonstrate significant bronchodilator reversibility (BDR). The pathologic features associated with the presence or absence of this phenomenon are not known. Methods: We analyzed 67 patients with advanced upper lobe predominant emphysema who underwent lung volume reduction surgery and divided them into 2 groups: the reversible group [BD(+)] had a >12% and >200 mL increase in FEV1 or FVC with bronchodilator; the irreversible group [BD(−)] had a ≤12% and ≤20 mL increase in FEV1 and FVC. We measured the epithelial height (EH) and areas of epithelium (EA), subepithelium (SEA), smooth muscle (SMWA), and total wall (TWA) of the small airways (<2 mm in internal diameter) in the resected specimens, and adjusted these measurements for basement membrane area (BMA) or perimeter (BMP). Results: Despite similar baseline characteristics, the BD(+) group had a smaller EH (0.036 mm vs. 0.042 mm, p = 0.005) and EH/BMP (0.012 vs. 0.014, p = 0.007), and a greater SMWA/BMA (0.491 vs. 0.430, p = 0.034) compared to the BD(−) group. In addition, EA trended to be smaller in the BD(+) group when compared to the BD(−) group (0.160 mm2 vs. 0.184 mm2, p = 0.06). In a subset of patients with consistent patterns of BDR on serial testing, the BD(+) group had greater SMWA/BMA (0.518 vs. 0.433, p = 0.049) and TWA/BMA (1.405 vs. 1.266, p = 0.036) compared to the BD(−) group. Conclusions: Small airway smooth muscle mass may play a role in determining BDR in severe emphysema.

Hyperpolarized3He MR Imaging: Physiologic Monitoring Observations and Safety Considerations in 100 Consecutive Subjects

To evaluate the safety of hyperpolarized helium 3 ((3)He) magnetic resonance (MR) imaging. Local institutional review board approval and informed consent were obtained. Physiologic monitoring data were obtained before, during, and after hyperpolarized (3)He MR imaging in 100 consecutive subjects (57 men, 43 women; mean age, 52 years +/- 14 [standard deviation]). The subjects inhaled 1-3 L of a gas mixture containing 300-500 mL (3)He and 0-2700 mL N(2) and held their breath for up to 15 seconds during MR imaging. Heart rate and rhythm and oxygen saturation of hemoglobin as measured by pulse oximetry (Spo(2)) were monitored continuously throughout each study. The effects of (3)He MR imaging on vital signs and Spo(2) and the relationship between pulmonary function, number of doses, and clinical classification (healthy volunteers, patients with asthma, heavy smokers, patients undergoing lung volume reduction surgery for severe emphysema, and patients with lung cancer) and the lowest observed Spo(2) were assessed. Any subjective symptoms were noted. Except for a small postimaging decrease in mean heart rate (from 78 beats per minute +/- 13 to 73 beats per minute +/- 11, P < .001), there was no effect on vital signs. A mean transient decrease in Spo(2) of 4% +/- 3 was observed during the first minute after gas inhalation (P < .001) in 77 subjects who inhaled a dose of 1 L for 10 seconds or less, reaching a nadir of less than 90% at least once in 20 subjects and of less than 85% in four subjects. There was no correlation between the lowest Spo(2) and pulmonary function parameters other than baseline Spo(2) (r = 0.36, P = .001). The lowest mean Spo(2) varied by 1% between the first and second and second and third doses (P < .001) and was unrelated to clinical classification (P = .40). Minor subjective symptoms were noted by 10 subjects. No serious adverse events occurred. Hyperpolarized (3)He MR imaging can be safely performed in healthy subjects, heavy smokers, and those with severe obstructive airflow limitation, although unpredictable transient desaturation suggests that potential subjects should be carefully screened for comorbidities.

Some pathogenic aspects of pulmonary emphysema in COPD patients

Histological and immunohistochemical investigations of lung tissue specimens were performed in 9 patients with COPD underwent lung volume reduction surgery. Lung tissue specimens of died persons without lung and heart pathology were as controls. Tissue expressions of endothelial growth factor (EGF), type 9 matrix metalloproteinase, type 1 matrix metalloproteinase (TIMP-1) tissue inhibitor, and transforming growth factor β1 (TGF β-1) have been studied. Patents with severe emphysema typically had focal interstitial fibrosis, interalveolar septa infiltrated with interstitial macrophages and lymphocytes, hypertrophy of media and proliferation of intima in the vascular wall, and arteriolar muscularization. There was significantly higher expression of EGF and TIMM-1 in the lung tissue of these patients compared with controls; this could confirm the presence of compensatory mechanisms of lung parenchyma destruction. Strong correlations were found between expression of EGF and TGF β-1, EGF and TIMP-1 which demonstrated a relationship between angiogenesis, proteolysis and fibrogenesis in development of emphysema.