Interventional bronchoscopy for the management of airway complications following lung transplantation.

STUDY OBJECTIVES: To assess the efficacy and complications of different interventional bronchoscopic techniques used to treat airway complications after lung transplantation. DESIGN: Retrospective study. SETTING: Heart-lung transplant unit of a university hospital. PATIENTS: From November 1986 to January 2000, interventional bronchoscopy was performed in 41 of 312 lung transplant recipients (13.1%) for tracheobronchial stenosis, bronchomalacia, granuloma formation, and dehiscence. INTERVENTIONS: Dilatation, stent placement, laser or forceps excision. MEASUREMENTS AND RESULTS: Mean (+/- SE) improvement in FEV(1) in 26 patients undergoing dilatation for a stenotic or a combined lesion was 93 +/- 334 mL or 8 +/- 21%. In seven of these patients not proceeding to stent placement, mean improvement in FEV(1) was 361 +/- 179 mL or 21 +/- 9%. Patients needing stent placement after dilatation had a mean change in FEV(1) after dilatation of - 5 +/- 325 mL or 3 +/- 23%, and an improvement of 625 +/- 480 mL or 52 +/- 43% after stent insertion. Mean improvement in FEV(1) for patients treated with stent insertion for bronchomalacia was 673 +/- 30 mL or 81 +/- 24%. Complications of airway stents were migration (27%), mucous plugging (27%), granuloma formation (36%), stent fracture (3%), and formation of a false passage (6%). Mortality associated with interventional bronchoscopy was 2.4% (1 of 41 patients). For patients with airway complications successfully undergoing interventional bronchoscopy, the overall 1-year, 3-year, and 5-year survival rates were 79%, 45%, and 32%, respectively, vs 87%, 69%, and 56% for those without airway complications (p < 0.05). CONCLUSION: Only a small number of patients with airway stenosis after lung transplantation will respond to bronchial dilatation alone. Patients with airway complications after lung transplantation have a higher mortality than patients without airway complications.     

Laser in treatment of lung cancer

We performed treatments with a Nd-YAG laser in 27 patients (19 men) with a mean age (+/- 1 SD) of 63 +/- 15 years for incomplete obstruction of the tracheobronchial tree due to non-oat cell malignant neoplasm associated with cough, dyspnea, hemoptysis, or unresolved atelectasis or pneumonia. Sixteen patients had been previously treated with surgery, chemotherapy, or irradiation. Before surgery,, their mean values were as follows: Karnofsky score, 41 +/- 15 percent; British Medical Research Council dyspnea index, 3.7 +/- 0.6; forced vital capacity (FVC), 64 +/- 23 percent of predicted; and mean forced expiratory volume in one second (FEV1), 52 +/- 19 percent of predicted. Immediate palliative relief was achieved in 23 patients and lasted one-half to six months after a single treatment. After surgery, the mean values were as follows: FVC, 77 +/- 26 percent of predicted; FEV1, 74 +/- 27 percent of predicted; Karnofsky score, 57 +/- 18 percent (p less than 0.05); and dyspnea index, 2.8 +/- 0.7 (p less than 0.05). Complications included one death, and two patients subsequently died of massive pulmonary hemorrhage within seven days of treatment. Rigid bronchoscopy was required in seven patients. We also performed laser treatments in 19 patients (eight men) with a mean age of 64 +/- 10 years who had complete bronchial obstruction due to non-oat cell malignant neoplasm; all but one had received previous non-laser treatment. Before surgery the mean values were as follows: Karnofsky score, 30 +/- 10 percent; dyspnea index, 3.7 +/- 0.5; FVC, 46 +/- 14 percent of predicted; and FEV1, 44 +/- 13 percent of predicted. Immediate relief was achieved in six cases and lasted 0.25 to 1.5 months after a single treatment. After surgery the mean values were as follows: FVC, 59 +/- 8 percent of predicted (p less than 0.05); FEV1, 48 +/- 13 percent of predicted; Karnofsky score, 34 +/- 16 percent; and dyspnea index, 3.4 +/- 0.5. Complications included two deaths, one associated with combustion of the outer sheath of the fiberoptic bronchoscope. Rigid bronchoscopy was required in five patients. Results suggest that laser therapy is most beneficial in patients with partial and not totally occluded airways (X2, p less than 0.05).     

Ultraflex stents for the management of airway complications in lung transplant recipients

OBJECTIVE: We present our experience with the use of the Ultraflex (nitinol) stents in the management of airway complications in lung transplant (LT) recipients. METHODOLOGY: Nine LT recipients underwent insertion of uncovered Ultraflex stents. Mean change in FEV1, duration to formation of granulation tissue and follow-up post-stent insertion were compared with results obtained in LT recipients who had undergone Gianturco stent (n = 10) and Wallstent insertion (n = 16). RESULTS: Mean improvement in FEV1 after insertion of Gianturco, Wallstent and Ultraflex stents was 670 +/- 591 mL, 613 +/- 221 mL and 522 +/- 391 mL, respectively. No patient with an Ultraflex stent developed mucus plugging or stenosis at stent extremity at a follow up of 263 +/- 278 days. The mean and median duration to stenosis at stent extremity for patients with Gianturco stents was 102 +/- 85 days and 73 days, respectively, compared with 132 +/- 87 days and 142 days, respectively, for patients with Wallstents. Stricture formation in the middle of the Ultraflex stent occurred bilaterally, at the level of anastomosis in one patient in whom stent placement was undertaken in the presence of inflammation. Stent migration in one patient was related to undersizing of the stent diameter relative to the airway diameter. A larger diameter relative stent was subsequently inserted successfully. CONCLUSION: Ultraflex stents appear to have fewer long-term complications when used in the management of airway complications following LT.     

Respiratory input impedance from 4 to 256 Hz in normals and chronic airflow obstruction: comparisons and correlations with spirometry.

Measurement of respiratory system input impedance (Zrs) by forced oscillation (FO) has generally been limited to frequencies less than or equal to 50 Hz, and correlations with spirometry have been variable. Using FO from 4 to 256 Hz in normals, Jackson and colleagues recently described a first acoustic antiresonance frequency (Far,1) at approximately 170 Hz. Using the same frequency range, we compared several Zrs spectral characteristics with spirometry in 12 chronic airflow obstruction (CAO) patients (range FEV1 0.8 to 2.0 L) and 10 matched controls. Compared with controls, patients had a higher first resonance frequency (Fr,1) (mean +/- SD = 15 +/- 5 versus 10 +/- 2 Hz, p less than 0.02) and a higher Far,1 (196 +/- 11 versus 172 +/- 13 Hz, p less than 0.0002). Good correlations occurred between % predicted FVC and the Far,1 (r = -0.81, p less than 0.0000), between FEV1/FVC and the reactance at 20 Hz (r = -0.6, p less than 0.003), between FEV1 and Far,1 (r = -0.74, p less than 0.0001). Because Far,1 may be affected by airway wall mechanical properties, the shift in Far,1 seen in these patients may be due to airway wall properties in CAO. We conclude that measurement of Zrs up to 256 Hz requires little patient cooperation and may be clinically useful. It can differentiate CAO patients from controls and correlates well with spirometry. The first acoustic antiresonance frequency may reflect airway mechanical properties and provide information not available from Zrs measured at lower frequencies.     

Pulmonary function improves after expandable metal stent placement for benign airway obstruction

STUDY OBJECTIVE: To determine whether expandable metal stent placement for benign airway lesions improves pulmonary function. DESIGN: Case series. SETTING: University medical center. PATIENTS: Nine patients who underwent balloon-mediated expandable metal stent deployment for airway obstruction due to benign etiologies. RESULTS: All nine patients had expandable stents deployed for benign airway lesions using fiberoptic bronchoscopy and fluoroscopic guidance. Pulmonary function improved after stent placement. The mean FVC increased by 388 mL (95% confidence interval [CI], 30 to 740 mL), the mean peak expiratory flow (PEF) increased by 1,288 mL (95% CI, 730 to 1,840 mL), the mean FEV1 increased by 550 mL (95% CI, 240 to 860 mL), and the mean forced expiratory flow between 25% and 50% of vital capacity (FEF25-75%) increased by 600 mL (95% CI, 110 to 1,090 mL). Corresponding relative measurements included increases in FVC (12%), PEF (95%), FEV1 (38%), and FEF25-75% (87%). The complete characterization of a benign airway obstruction generally required a multimodal approach. CONCLUSIONS: Expandable metal stent placement appears to be an effective therapy for benign airway obstruction.     

Frequency and mechanism of daytime pulmonary hypertension in patients with obstructive sleep apnoea syndrome

In order to study the frequency and the mechanisms of daytime pulmonary hypertension (PH) in obstructive sleep apnoea syndrome (OSAS) lung function tests, blood gas analysis and right-heart catheterization were performed in 46 consecutive patients. OSAS was assessed by polysomnography. 9 patients only (20%) had PH (mean pulmonary artery pressure (Ppa) greater than or equal to 20 mmHg). Patients with PH had lower daytime PaO2 (60.8 +/- 7.6 vs. 76.2 +/- 9.4 mmHg; p less than 0.001), higher daytime PaCO2 (44.8 +/- 4.2 vs. 38.0 +/- 4.0 mmHg; p less than 0.001), lower forced vital capacity (FVC) and forced expiratory volume (FEV1) (p less than 0.001), but the severity of OSAS was not different whether PH was present or not (apnoea index: 62 +/- 34 hour in the PH group vs. 65 +/- 40 hour, apnoea + hypopnoea index 102 +/- 33 hour in the PH group vs. 86 +/- 36 hour, lowest sleep SaO2: 59 +/- 21% in the PH group vs. 66 +/- 18%). There were significant correlations between Ppa and: daytime PaO2 (r = -0.61; p less than 0.001), PaCO2 (r = 0.55; p less than 0.001), FEV1 (r = -0.52; p less than 0.001) but not between Ppa and apnoea index, apnoea + hypopnoea index, lowest sleep SaO2. PH and daytime hypoxaemia were associated either with chronic airway obstruction or with severe obesity.     

Elevated bronchoalveolar lavage fluid histamine levels in allergic asthmatics are associated with increased airway obstruction

Bronchoalveolar lavage (BAL) fluid was evaluated for histamine and tryptase levels in 61 samples (46 samples from 24 atopic asthmatics, seven samples from seven patients with allergic rhinitis, and eight samples from eight normal volunteers). Asthmatics and patients with allergic rhinitis had significantly higher BAL histamine than did normal subjects (169 +/- 22, 141 +/- 23, 42 +/- 6 pg/ml, respectively; p less than 0.05, both comparisons). BAL fluid tryptase levels were also higher in asthmatics and patients with allergic rhinitis than in normal subjects (0.36 +/- 0.03, 0.38 +/- 0.05, 0.23 +/- 0.04 ng/ml, respectively; p less than 0.05, both comparisons); however, levels of tryptase and histamine in BAL were not correlated (r = -0.03 in the group as a whole, r = -0.12 in the asthmatic group). BAL concentration of histamine correlated inversely with FEV1 percent predicted in the asthmatic group (r = -0.44, p less than 0.005). Asthmatics with high BAL fluid histamine (greater than or equal to 100 pg/ml, n = 23) had lower FEV1 percent predicted (80 +/- 3% versus 96 +/- 3%, p = 0.0005), lower FEV1/FVC ratio (72 +/- 1% versus 77 +/- 2%, p less than 0.05), higher percentage of BAL eosinophils (2.2 +/- 0.4% versus 0.6 +/- 0.1%, p less than 0.002), and greater airway responsiveness (lower PD20 [13.1 +/- 3.4 versus 41.5 +/- 13.7 cumulative breath units, p less than 0.05]) compared with asthmatics with low BAL fluid histamine (less than 100 pg/ml, n = 23).(ABSTRACT TRUNCATED AT 250 WORDS)     

Does lithium carbonate affect the ion transport abnormality in cystic fibrosis?

Lithium is known to affect several aspects of cellular regulation which may be related to ion channel function in epithelial cells. To determine whether the ion transport abnormality in cystic fibrosis (CF) is affected by lithium with resultant changes in clinical status, 36 CF patients, 12-37 years old, were enrolled in a 14 week, double-blind, placebo-controlled trial. Eighteen patients were randomly assigned to receive lithium carbonate for 10 weeks. At the end of therapy their average serum lithium concentration was 0.56 +/- 0.06 mmol (SEM) per liter. Their sweat chloride concentration fell from 92.1 +/- 4.8 mmol per liter to 87.4 +/- 4.0 mmol per liter after 10 weeks of therapy (P = 0.07) and rose to 94.4 +/- 3.5 mmol per liter 4 weeks after end of therapy (P less than 0.001 compared to results at end of therapy). Their forced vital capacity (FVC) fell from 72 +/- 5.3% of predicted to 66 +/- 5.1% of predicted after 4 weeks of therapy (P less than 0.01), and their forced expiratory volume in one second (FEV1) fell from 56 +/- 5.5% of predicted to 51 +/- 5.5% of predicted after 4 weeks of therapy (P less than 0.01). In a non-blind assessment, performed 19 weeks after the end of therapy, their FVC and FEV1 had risen and were not significantly different from baseline. Sweat chloride, FVC, and FEV1 remained unchanged in the placebo group throughout the period of study.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of natural and Dumon airway stents for the management of benign tracheobronchial stenoses

Objective and background:   To investigate the utility and safety of the 'Natural stent', a newly designed silicone airway stent, the authors compared clinical outcomes and complications in patients who underwent silicone airway stenting for the management of benign airway stenosis.
Methods:   The medical records of 94 patients requiring the placement of 100 airway stents (43 Dumon and 57 Natural) were retrospectively reviewed in a tertiary referral hospital.
Results:   Post-tuberculous stenosis was the leading indication for airway stenting (74%), followed by post-intubation stenosis (21%). After intervention, dyspnoea improved in patients who underwent Dumon (90%) and Natural (86%) stenting. After stabilizing dyspnoea, stents could be successfully removed in half of the patients who underwent Dumon (54%) or Natural (49%) stenting. During a 42-month follow-up period, complication rates were similar in patients who underwent Dumon or Natural stenting.
Conclusion:   Natural airway stent was as effective and safe as Dumon stent for the management of benign tracheobronchial stenoses.     

Pulmonary function characteristics in patients with different patterns of methacholine airway hyperresponsiveness

STUDY OBJECTIVES: The American Thoracic Society guidelines for methacholine-induced airway hyperresponsiveness include a > or = 20% reduction in FEV(1) or a > or = 40% reduction in specific airway conductance (sGaw). The objectives of the current study are to assess the concordance between these two criteria and to characterize the pulmonary function and respiratory symptoms of patients with different patterns of methacholine hyperresponsiveness. STUDY DESIGN: A prospective study of 248 consecutive patients referred for methacholine bronchoprovocation testing. RESULTS: Positive methacholine hyperresponsiveness was noted in 179 patients; 139 patients (78%) had a > or = 20% reduction in FEV(1), whereas 40 patients (22%) had a > or = 40% reduction in sGaw alone without a significant change in FEV(1). The former group had the following: (1) higher baseline lung volumes, (2) lower baseline values of FEV(1) and sGaw, (3) forced expiratory flow between 25% and 75% of vital capacity (FEF(25-75))/FVC ratios compared to patients with a reduction in sGaw alone (0.72 +/- 0.26 vs 0.97 +/- 0.28, mean +/- SD; p < 0.0001), and (4) more frequent presence of wheezing and chest tightness (p < 0.05). CONCLUSIONS: First, a substantial number of patients have a reduction in SGaw alone in response to methacholine, and secondly, this response is seen in patients with a higher FEF(25-75)/FVC ratio. Since the FEF(25-75)/FVC ratio is thought to be an index of airway size relative to lung size, we speculate that the larger intrinsic airway size relative to lung size may explain the differences in baseline parameters and patterns of methacholine hyperresponsiveness.     

No effect of oral high frequency oscillation combined with forced expiration manoeuvres on tracheobronchial clearance in chronic bronchitis

This study compared the effect of oral high frequency oscillation (OHFO) with the effect of the forced expiration technique (FET) on tracheobronchial clearance. Eight patients with chronic bronchitis were investigated (mean age 60 +/- 10 yrs, mean forced expiratory volume in one second (FEV1) 68 +/- 27% predicted, mean sputum production 33 +/- 9 g.day-1). OHFO was applied at the respiratory system resonant frequency of each patient (range 9.2-25 Hz) and combined with huffing. FET included breathing exercises, huffing and postural drainage. Duration of both OHFO and FET was 30 minutes. Tracheobronchial clearance was measured by means of a radio-aerosol technique. At 60 mins after start of the treatment mean tracheobronchial retention was 70 +/- 26% after OHFO, 54 +/- 26% after FET and 76 +/- 18% in the control run, which included huffing only. OHFO was not significantly different from control. FET was significantly different (p less than 0.02) from both OHFO and control. It is concluded that OHFO has no effect on tracheobronchial clearance in chronic bronchitis.     

Do NHLBI lung function criteria apply to children? A cross‐sectional evaluation of childhood asthma at National Jewish Medical and Research Center, 1999–2002

Although National Heart Lung Institute (NHLBI) guidelines categorize asthma severity based on spirometry, few studies have evaluated the utility of these spirometric values in grading asthma severity in children. Asthma is thought to be progressive, but little is known about the loss of lung function in childhood. This study sought to determine the spirometric indices in children from 4-18 years of age. Retrospective cross-sectional analysis was performed on all spirometries done in children at the National Jewish Medical and Research Center from 1999-2002. In total, 2,728 children performed 24,388 measures. The mean +/- SD values for forced vital capacity (FVC), forced expired volume in 1 sec (FEV(1)), FEV(1)/FVC ratio, and forced expiratory flow (FEF)(25-75) were 92.7 +/- 16.2, 92.2 +/- 18.0, 85.3 +/- 9.3, and 78.0 +/- 36.5 percent predicted, respectively. Seventy-seven percent of FEV(1) values were >/= 80%, 18.6% were between 60-80%, and 3.1% were <60% of predicted. FEV(1) was highest in 5-year-old children; it declined thereafter, reaching a nadir at 11 years, followed by a partial recovery from 12-18 years. Expressed in liters, FEV(1) values were lower than expected at every age, with the greatest difference at 18 years. FEV(1)/FVC ratios declined through childhood, suggesting impaired airway but not lung growth in children with asthma. In conclusion, the majority of asthmatic children attending a tertiary care facility had FEV(1) values within normal range. With increasing age, the increase in FEV(1) lags behind that of nonasthmatics, so that by 18 years, maximum FEV(1) is impaired. The NHLBI FEV(1) cutoff values do not appear to accurately stratify pediatric asthma, and no useful FEV(1) cutoff could be generated.     

Sensitivity of spirometric measurements to detect airway obstruction in infants

We evaluated the ability of forced expiratory flow volume curves from raised lung volumes to assess airway function among infants with differing severities of respiratory symptoms. Group 1 (n = 33) had previous respiratory symptoms but were currently asymptomatic; group 2 (n = 36) was symptomatic at the time of evaluation. As a control group, we used our previously published sample of 155 healthy infants. Flow volume curves were quantified by FVC, FEF50, FEF75, FEF25-75, FEV0.5, and FEV0.5/FVC, which were expressed as Z scores. All variables except FVC had Z scores that were significantly less than zero and distinguished groups 1 and 2 with progressively lower Z scores. The mean Z scores of the flow variables (FEF50%, FEF75%, and FEF25-75%) were more negative than the Z scores for the timed expired volumes (FEV0.5 or FEV0.5/FVC) for both groups. In general, measures of flow identified a greater number of infants with abnormal lung function than measures of timed volume; FEF50 had the highest performance in detecting abnormal lung function. In summary, forced expiratory maneuvers obtained by the raised volume rapid compression technique can discriminate among groups of infants with differing severity of respiratory symptoms, and measures of forced expiratory flows were better than timed expiratory volume in detecting abnormal airway function.     

激光加气道内支架在气道完全闭塞治疗中的应用

目的探讨气道内激光加内置支架在气道完全闭塞治疗中的应用价值.方法对17例气道完全闭塞患者应用掺钕钇铝石榴石激光加气道内置支架治疗,并定期随访2～20个月.结果17例患者经激光治疗后气道均有扩大,平均扩大(5.82±1.01)mm;气促分级减少,除1例患者无变化外,减少1级4例,2级减少11例,3级减少1例;1秒钟用力呼气容积(FEV1)增加(0.49±0.18)L.14例患者经激光治疗后行气道内支架置入术,术后患者的气道直径平均又增大(3.50±0.94)mm;气促分级又进一步减少,除2例患者无变化外,有8例减少1级,4例减少2级;FEV1平均又增加(0.41±0.20)L.在激光治疗过程中有15例患者出现低氧血症,2例患者出现出血,有3例患者术后早期出现呼吸困难;支架置入后出现反复肺部感染者4例,支架网眼内肉芽组织或肿瘤组织生长形成阻塞5例,支架出现移位1例,经处理后气道均保持通畅.结论激光治疗加气道内置支架在气道完全闭塞患者的治疗中是行之有效的.     

Evidence against routine scheduling of surveillance bronchoscopy after stent insertion

STUDY OBJECTIVES: To determine whether routine scheduling of surveillance flexible fiberoptic bronchoscopy is warranted within 2 to 3 months after silicone stent insertion for central airway obstruction. DESIGN: Retrospective cohort study. SETTING: University medical center. PATIENTS: All patients with silicone stents placed for benign or malignant tracheobronchial obstruction during a 3-year period. METHODS: Incidence of stent-related complications, new respiratory symptoms, and need for therapeutic bronchoscopic intervention were noted in patients undergoing surveillance bronchoscopy (SFFB) and emergency bronchoscopy (EFFB), defined as flexible fiberoptic bronchoscopy prompted by onset of new symptoms before the date of scheduled SFFB. RESULTS: One hundred one silicone stents were inserted in 88 patients (47 with cancer, 41 with benign disease). Eighteen patients died within 2 months and had no bronchoscopy. Seventy patients underwent either SFFB or EFFB. Stent-related complications were detected in 9 of 31 asymptomatic patients (29%) undergoing SFFB; all had received tumor-specific therapy after stent insertion (in 7 of 8 patients [88%] reporting new respiratory symptoms at the time of SFFB, and in 26 of 31 patients [84%] undergoing EFFB). Overall, stent-related complications were detected in nine asymptomatic patients (10% of total), of which only four patients (5% of total, but 13% of all asymptomatic patients) required therapeutic interventions. CONCLUSION: Routine SFFB within 2 to 3 months after stent insertion did not detect a high incidence of stent-related complications among patients without new respiratory symptoms.     

The role of FEV6 in the detection of airway obstruction

OBJECTIVES: There are recent reports regarding the use of forced expiratory volume in 6 s (FEV6) in place of forced expiratory vital capacity (FVC) in the detection of airway obstruction. We aimed to investigate the role of FEV6 in comparison with FVC in the evaluation of airway obstruction. METHODS: The pulmonary function tests (PFT) results of all 5114 patients, who had been tested in the pulmonary function laboratory between 1998 and 2003, were retrospectively analyzed to investigate the relationship between FEV6 and FVC. RESULTS: We have found a mean difference of 95.35+/-121.7 (min=0, max=1050) ml (3.37%) when FVC and FEV6 values (FVC-FEV6) of all cases were compared. This difference was found to be higher (180 ml, 7.3%) in patients with airway obstruction. When FEV1/FVC is taken as the gold standard, FEV1/FEV6 had negative predictive value of 92.24% and a sensitivity of 86.09% in the detection of airway obstruction. CONCLUSIONS: Although it is easier to use FEV6 in place of FVC, relatively low sensitivity in that setting may result in the underestimation of airway obstruction. This drawback should be kept in mind when FEV6 is utilized to detect airway obstruction.     

Factors predicting outcome following airway stenting for post-tuberculosis tracheobronchial stenosis

Background and objective: Silicone airway stents are used to widen narrowed airways in patients with post‐tuberculosis tracheobronchial stenosis (PTTS). After mechanical stabilization, stents can be removed from the majority of patients leaving restored airway patency. However, in a significant minority re‐stenosis develops post‐sten removal thus necessitating surgical intervention or long‐term stenting. In this study, we sought to establish prognostic factors for successful airway intervention in PTTS. Methods: We retrospectively investigated 71 patients who underwent silicone stenting due to PTTS. After stenting, bronchoscopic toileting and/or repositioning was performed during follow up. At 6–12 months after clinical stabilization, stents were planned to be removed. Patients with patent airways were followed if no further intervention was required. If restenosis developed, patients underwent re‐stenting or operation. Clinical parameters were analysed to determine favourable prognostic factors. Results: Stents were successfully removed in 40 patients at a median 12.5 months after insertion. In 27 patients, stent re‐insertion was carried out and four patients underwent surgical management. Multivariate logistic regression analysis revealed that successful stent removal was independently associated with atelectasis <1 month before bronchoscopic intervention, and absence of complete lobar atelectasis. Conclusions: Airway intervention, including silicone stenting, can be successful in patients with PTTS, when the intervention is performed within 1 month of atelectasis and before complete lobar atelectasis.     

Ratio between forced expiratory flow between 25% and 75% of vital capacity and FVC is a determinant of airway reactivity and sensitivity to methacholine

STUDY OBJECTIVE: The ratio between forced expiratory flow between 25% and 75% of vital capacity (FEF(25-75)) and FVC is thought to reflect dysanapsis between airway size and lung size. A low FEF(25-75)/FVC ratio is associated with airway responsiveness to methacholine in middle-aged and older men. The current study was designed to assess this relationship in both male and female subjects over a broader range of ages. STUDY DESIGN: Data analysis of consecutive subjects who had a >or= 20% reduction in FEV(1) after 相似文献   

Lung function 5 yr after lung volume reduction surgery for emphysema

Current datum more than 2 yr after lung volume reduction surgery (LVRS) for emphysema is limited. This prospective study evaluates pre-LVRS baseline and 5-yr results in 26 symptomatic patients (mean age 67 +/- 6 yr) (mean +/- SD) who underwent bilateral, targeted upper lobe stapled LVRS using video-assisted thoracoscopy. Baseline forced expiratory volume in 1 s (FEV(1)) was 0.7 +/- 0.2 L (mean +/- SD), 29 +/- 10% predicted. Following LVRS, with none lost to follow-up, mortality due to respiratory failure at 0.5, 1, 2, 3, 4, and 5 yr was 4%, 4%, 19%, 31%, 46%, and 58%, respectively. Increase above baseline for FEV(1) > 200 ml and/or FVC > 400 ml at 1, 2, 3, 4, and 5 yr post-LVRS was noted in 73%, 46%, 35%, 27%, and 8% of all patients; decrease in dyspnea grade >/= 1 in 88%, 69%, 46%, 27%, and 15%; and elimination of initial oxygen dependence in 18 patients in 78%, 50%, 33%, 22%, and 0%, respectively. Expiratory airflow improved due to the increase in both lung elastic recoil and small airway intraluminal caliber. Five patients decreased FEV(1) 141 +/- 60 ml/yr and FVC 102 +/- 189 ml/yr over 3.8 +/- 1.2 yr post-LVRS, similar to their pre-LVRS rate of decline. In the 11 patients who survived 5 yr, at 0.5-1.0 yr post-LVRS peak increase in FEV(1) was 438 +/- 366 ml, with a decline of 149 +/- 157 ml the following year and 78 +/- 59 ml/yr over 4.0-4.5 yr. Bilateral LVRS provided palliative clinical and physiological improvement in 9 of 26 patients at 3 yr, 7 at 4 yr, and 2 at 5 yr.     

Static lung volumes in patients with Cushing's disease.

OBJECTIVE: Numerous clinical manifestations have been described in association with Cushing's syndrome. There are no eligible data on pulmonary function tests in Cushing's disease (CD). We aimed to asses pulmonary function tests including spirometry in a series of patients with active CD. MATERIALS AND METHODS: This cross-sectional study comprised 10 patients with Cushing's disease (F/M, 9/1). The forced expiratory volume in 1st second (FEV1), the forced vital capacity (FVC), the FEV1/FVC ratio and the forced expiratory flow over the middle half of the FVC (FEF 25-75%) values and predicted values were determined by spirometry. RESULTS: Mean age, height, weight, body mass index were 36.7+/-12.6 yrs (range 22-63 years), 156.9+/-8.4 cm, 74.1+/-10.7 kg, 29.6+/-3.8 kg/m(2), respectively. Spirometric abnormalities (impairment of FEV1, FVC, FEV1/FVC and FEF 25-75 values) were not detected, and there were no significant differences compared to reference values. Disease duration and cortisol concentrations by HDDSTs were negatively correlated with predicted FEV1/FVC values and the percentage of predicted FEV1 ratios, respectively. DISCUSSION: The lung volume and ventilatory performance by spirometry were not disturbed in patients with endogenous hypercostisolism due to Cushing's disease.