Pulmonary hemodynamics in advanced COPD candidates for lung volume reduction surgery or lung transplantation

STUDY OBJECTIVES: To assess the pulmonary hemodynamic characteristics in COPD candidates for lung volume reduction surgery (LVRS) or lung transplantation (LT). DESIGN: Retrospective study. SETTING: One center in France. PATIENTS: Two hundred fifteen patients with severe COPD who underwent right-heart catheterization before LVRS or LT. RESULTS: Mean age was 54.6 years. Pulmonary function test results were as follows: FEV(1), 24.3% predicted; total lung capacity, 128.3% predicted; residual volume, 259.7% predicted. Mean pulmonary artery pressure (PAPm) was 26.9 mm Hg. Pulmonary hypertension (PAPm > 25 mm Hg) was present in 50.2% and was moderate (PAPm, 35 to 45 mm Hg) or severe (PAPm > 45 mm Hg) in 9.8% and in 3.7% of patients, respectively. Cardiac index was low normal. PAPm was related to Pao(2) and alveolar-arterial oxygen gradient in multivariate analysis. Cluster analysis identified a subgroup of atypical patients (n = 16, 7.4%) characterized by moderate impairment of the pulmonary mechanics (mean FEV(1), 48.5%) contrasting with high level of pulmonary artery pressure (PAPm, 39.8 mm Hg), and severe hypoxemia (mean Pao(2), 46.2 mm Hg). CONCLUSION: While pulmonary hypertension is observed in half of the COPD patients with advanced disease, moderate-to-severe pulmonary hypertension is not a rare event in these patients. We individualized a subgroup of patients presenting with a predominant vascular disease that could potentially benefit from vasodilators.     

Risk of progression to active tuberculosis among foreign-born persons with latent tuberculosis

BACKGROUND: Increased risk for tuberculosis (TB) disease has been identified in foreign-born persons in the United States, particularly during the first 5 years after their arrival in the United States. This could be explained by undetected TB disease at entry, increased prevalence of latent TB infection (LTBI), increased progression from LTBI to TB, or a combination of these factors. METHODS: We performed a cluster analysis of TB cases in Boston and a case-control study of risk factors for TB with an unclustered isolate among Boston residents with LTBI to determine whether such persons have an increased risk for reactivation of disease. RESULTS: Of 321 case patients with TB seen between 1996 and 2000, 133 isolates were clustered and 188 were not. In multivariate analysis, foreign birth was associated with an unclustered isolate (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.2 to 3.8; p < 0.01), while being a close contact of a TB case was negatively associated (OR, 0.22; 95% CI, 0.07 to 0.73; p = 0.02). When 188 TB patients with unclustered isolates were compared to 188 age-matched control subjects with LTBI, there was no association between the occurrence of TB and foreign birth (OR, 0.71; 95% CI, 0.42 to 1.3); among foreign-born persons, there was no association between the occurrence of TB and being in the United States 相似文献   

Prevalence and reversibility of pulmonary dysfunction in refractory systemic lupus: improvement correlates with disease remission following hematopoietic stem cell transplantation

AIM: To report the prevalence and reversibility of pulmonary function test (PFT) abnormalities among systemic lupus erythematosus (SLE) patients, refractory to therapy, undergoing hematopoietic stem cell transplantation (HSCT). METHODS: Thirty-four SLE patients received 200 mg/kg cyclophosphamide and 90 mg/kg equine antithymocyte globulin followed by HSCT. PFTs were performed prior to, at 6 months, and yearly following HSCT. RESULTS: The prevalence of significant PFT abnormalities was high (97%). Low FEV(1) and FVC occurred in 26 of 34 patients (76%). A significant abnormality in diffusion capacity of the lung for carbon monoxide (Dlco) occurred in 26 of 32 individuals able to complete Dlco testing (81%). Dlco 18 months after HSCT. Five of 28 patients had a normal entry FVC; for each, the FVC remains normal. Of the 23 patients with an abnormal baseline FVC, 18 have improved, 15 completely and 3 partially. Eight of these 18 patients also have improved Dlco. The two patients with a diagnosis of SLS and one patient with SLE-related pulmonary hypertension improved in both parameters. Only 5 of 23 patients with an abnormal FVC did not improve. Each of these five patients retained active lupus in spite of HSCT. CONCLUSION: The prevalence of lung impairment among SLE patients requiring long-term immune suppression is high. Following HSCT, pulmonary impairments can improve, which is sustained if disease control is sustained.     

Health-related quality of life trajectories among adults with tuberculosis: differences between latent and active infection

BACKGROUND: Tuberculosis (TB) remains a public health threat with significant annual impacts on morbidity and mortality. However, few studies have examined the impact of active and latent TB infection (LTBI) on health-related quality of life (HRQL). METHODS: Patients with recently diagnosed active TB or LTBI patients were administered the Short Form-36 (SF-36) and the Beck depression inventory (DI) at baseline, 3 months, and 6 months. Mixed-effect linear regression was used to compare the trajectory of HRQL over time in the two patient groups after adjusting for potential confounders. Ordinal logistic regression was used to determine the relationship between changes in HRQL of at least the minimal important difference. RESULTS: One hundred four active TB and 102 LTBI patients participated. At baseline, participants with active TB had significantly lower SF-36 mean domain and component scores (4 to 12 points lower, p < 0.03) and higher mean Beck DI scores (4 points higher, p < 0.0001) when compared to LBTI participants. In the responder analysis, those with active TB were associated with reporting improved scores at 6 months of at least the minimal important difference in vitality (odds ratio [OR], 2.7; 95% confidence interval [CI], 1.3 to 5.6), role physical (OR, 3.1; 95% CI, 1.4 to 6.5), mental component score (OR, 3.2; 95% CI, 1.5 to 6.9), social functioning (OR, 11.1; 95% CI, 3.8 to 33), and role emotional (OR, 2.7; 95% CI, 1.2 to 6.0). CONCLUSIONS: Active TB patients had large improvements in most HRQL domains by 6 months. However, when compared to LTBI participants and US norms, HRQL was still low at completion of therapy.     

Tiotropium and simplified detection of dynamic hyperinflation

STUDY OBJECTIVE: To detect dynamic hyperinflation (DH) by evaluating reduction in inspiratory capacity (IC) during metronome-paced hyperventilation (MPH) in patients with moderate-to-severe COPD, studied before and after treatment with tiotropium. METHODS: IC and FEV(1) were measured before and immediately after MPH at two times resting the respiratory rate for 20 s in 60 COPD patients (28 men; mean age, 66 +/- 10 years [+/- SD]) before and after 30 days of treatment with tiotropium bromide, 18 mug. Patients were encouraged to maintain a constant tidal volume during MPH. RESULTS: At baseline, mean FEV(1) was 1.5 +/- 0.1 L (+/- SE) [57 +/- 1.6% of predicted], mean FVC was 2.6 +/- 0.1L (77 +/- 1.8% of predicted), and mean FEV(1)/FVC was 56 +/- 1%. After 180 mug of aerosolized albuterol sulfate, mean FEV(1) was 1.7 +/- 0.1 L (63 +/- 1.5% of predicted) [p < 0.001] and mean FEV(1)/FVC was 58 +/- 1%. Compared to baseline, after 30 days and 1.5 h after tiotropium there was an increase in IC of 0.18 +/- 0.04L (p < 0.0001); FEV(1) of 0.13 +/- 0.03 L (5.6 +/- 0.8% of predicted; p = 0.0002); FVC of 0.22 +/- 0.05 L (6.5 +/- 1.3% of predicted; p < 0.001); and decrease in end-expiratory lung volume (EELV)/total lung capacity (TLC) of - 3.1 +/- 0.6% (p = 0.0001); a decrease in end-inspiratory lung volume (EILV)/TLC of - 2.9 +/- 1.3% (p = 0.03); and no change in TLC (- 0.06 +/- 0.05 L). Results following MPH-induced DH at baseline and after 30 days of tiotropium were similar, with decreases in IC (- 0.35 +/- 0.03 L; p < 0.001); FEV(1) (- 0.05 +/- 0.04 L; p = 0.2); and FVC (- 0.22 +/- 0.03 L; p < 0.0001); no change in TLC; and increases in EELV/TLC (11.8 +/- 1.0% of predicted; p < 0.0001) and EILV/TLC (4.0 +/- 1.3% of predicted, p < 0.003). CONCLUSION: In patients with moderate-to-severe COPD, tiotropium did not reduce MPH-induced DH and reduction in IC, compared to baseline. However, because tiotropium induced bronchodilation and increased baseline IC, lower operational lung volumes may blunt the effect of MPH-induced DH. The noninvasive simplicity of MPH-induced DH provides a clinically useful screening surrogate to monitor changes in IC following treatment with tiotropium.     

Factors associated with failure to complete isoniazid treatment for latent tuberculosis infection in Rhode Island

BACKGROUND: The treatment of latent tuberculosis infection (LTBI) is essential for tuberculosis elimination in the United States, but the major limitation is poor adherence to therapy. To aid the design of targeted adherence interventions, we investigated the factors associated with noncompletion of isoniazid (INH) therapy for LTBI. METHODS: A retrospective analysis of patients with who failed to complete vs those who completed 9 months of INH therapy at the RISE TB Clinic (Miriam Hospital; Providence, RI) in 2003 was performed. Factors associated with treatment noncompletion were examined using univariate and multiple logistic regression analysis. RESULTS: Of 845 patients with LTBI, 690 patients (81.6%) initiated INH therapy, of whom 426 patients (61.7%) completed therapy, and 246 patients (35.6%) were lost to follow-up. Treatment was discontinued in 18 patients (2.6%). Patients who failed to complete therapy were younger (mean age, 30.6 vs 33.8 years, respectively; p = 0.006), and were more likely to be uninsured (42.9% vs 29.8%, respectively; p = 0.0004), to be postpartum (66.7% vs 37.3%, respectively; p = 0.043), and to report treatment side effects (54.8% vs 30.1%, respectively; p < 0.0001). Reported treatment side effects (odds ratio [OR], 3.6; 95% confidence interval [CI], 2.2 to 6.2) and lack of medical insurance (OR, 1.7; 95% CI, 1.1 to 2.7) were each associated with treatment noncompletion in a model including both. Also, pregnant women were more likely than nonpregnant women to fail to initiate INH treatment (52.1% vs 14.7%, respectively; p < 0.0001). CONCLUSIONS: LTBI patients who are young, pregnant or postpartum, uninsured, and/or report treatment side effects may require additional case management to improve INH treatment completion rates.     

Zinc chloride (smoke bomb) inhalation lung injury: clinical presentations, high-resolution CT findings, and pulmonary function test results

STUDY OBJECTIVES: Zinc chloride smoke inhalation injury (ZCSII) is uncommon and has been rarely described in previous studies. We hypothesized that structural changes of the lung might correlate with pulmonary function. To answer this question, we correlated findings from high-resolution CT (HRCT) scan and the results of pulmonary function tests (PFTs) in patients with ZCSII. DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENTS: Twenty patients who had been hospitalized with ZCSII-related conditions. MEASUREMENTS: The study included HRCT scan scores (0 to 100), static and dynamic lung volumes, and diffusing capacity of the lung for carbon monoxide (D(LCO)). RESULTS: HRCT scans and PFTs were performed initially after injury (range, 3 to 21 days) in all patients and during the follow-up period (range, 27 to 66 days) in 10 patients. The predominant CT scan findings were patchy or diffuse ground-glass opacities with or without consolidation. The majority of patients showed a significant reduction of FVC, FEV1, total lung capacity, and D(LCO), but normal FEV1/FVC ratio values. Changes of functional parameters correlated well with HRCT scan scores. Substantial improvements in CT scan abnormalities and pulmonary function were observed at follow-up. CONCLUSIONS: The majority of our patients with ZCSII presented with a predominant parenchymal injury of the lung that was consistent with a restrictive type of functional impairment and a reduction in Dlco rather than with obstructive disease. Our results suggest that HRCT scanning and pulmonary function testing may reliably predict the severity of ZCSII.     

Pericardial abnormalities predict the presence of echocardiographically defined pulmonary arterial hypertension in systemic sclerosis-related interstitial lung disease

OBJECTIVES: To determine the prevalence and significance of pericardial abnormalities in systemic sclerosis (SSc)-related interstitial lung disease (ILD). METHODS: Retrospective study of 41 subjects with SSc-related ILD who underwent evaluation including thoracic high-resolution CT (HRCT) imaging, transthoracic echocardiography (TTE), and pulmonary function testing. HRCT review evaluated the pericardium for the presence of pericardial effusion (PEf), thickness of the anterior pericardial recess (APR) [abnormal defined as > 10 mm], and pericardial thickening as calculated by total pericardial score (TPS) [abnormal defined as > 8 mm]. Pulmonary arterial hypertension (PAH) was defined as a pulmonary artery pressure > 35 mm Hg estimated by TTE. RESULTS: Fifty-nine percent had an abnormal pericardium, 49% had a PEf, 56% had an abnormal APR, and 49% had an abnormal TPS. An abnormal pericardium was more common in men than women. Subjects with and without pericardial abnormalities were otherwise similar with respect to age, SSc classification, autoantibodies, ILD radiographic pattern, and presence of esophageal dilation. Both groups had similar median percentage of predicted total lung capacity, percentage of predicted FVC, percentage of predicted FEV(1), and percentage of predicted diffusion capacity of the lung for carbon monoxide. Subjects with pericardial abnormalities were more likely to have coexistent PAH (35% vs 75%; p = 0.02) and a higher median right ventricular systolic pressure (31 mm Hg vs 44 mm Hg; p = 0.03). Multiple logistic regression revealed that TPS was the best individual predictor of the presence of TTE-defined PAH. CONCLUSIONS: In patients with SSc-related ILD, pericardial abnormalities are commonly seen on HRCT, and their presence is strongly associated with echocardiographically defined PAH, with abnormal TPS as the best individual predictor.     

Development and validation of a survey-based COPD severity score

OBJECTIVE: To develop a comprehensive disease-specific COPD severity instrument for survey-based epidemiologic research. STUDY DESIGN AND SETTING: Using a population-based sample of 383 US adults with self-reported physician-diagnosed COPD, we developed a disease-specific COPD severity instrument. The severity score was based on structured telephone interview responses and included five overall aspects of COPD severity: respiratory symptoms, systemic corticosteroid use, other COPD medication use, previous hospitalization or intubation, and home oxygen use. We evaluated concurrent validity by examining the association between the COPD severity score and three health status domains: pulmonary function, physical health-related quality of life (HRQL), and physical disability. Pulmonary function was available for a subgroup of the sample (FEV1, n = 49; peak expiratory flow rate [PEFR], n = 93). RESULTS: The COPD severity score had high internal consistency reliability (Cronbach alpha = 0.80). Among the 49 subjects with FEV1 data, higher COPD severity scores were associated with poorer percentage of predicted FEV1 (r = - 0.40, p = 0.005). In the 93 subjects with available PEFR measurements, greater COPD severity was also related to worse percentage of predicted PEFR (r = - 0.35, p < 0.001). Higher COPD severity scores were strongly associated with poorer physical HRQL (r = - 0.58, p < 0.0001) and greater restricted activity attributed to a respiratory condition (r = 0.59, p < 0.0001). Higher COPD severity scores were also associated with a greater risk of difficulty with activities of daily living (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.8 to 3.0) and inability to work (OR, 4.2; 95% CI, 3.0 to 5.8). CONCLUSION: The COPD severity score is a reliable and valid measure of disease severity, making it a useful research tool. The severity score, which does not require pulmonary function measurement, can be used as a study outcome or to adjust for disease severity.     

Right and left ventricular function and pulmonary artery pressure in patients with bronchiectasis

BACKGROUND: Bronchiectasis may have deleterious effects on cardiac function secondary to pulmonary hypertension (PH). This study was designed to assess cardiac function and determine the prevalence of PH in patients with cystic and cylindrical bronchiectasis. METHODS: A cross-sectional study of patients with bronchiectasis diagnosed by CT scan was conducted at King Khalid University Hospital, Riyadh, Saudi Arabia between December 2005 and January 2007. Pulmonary function tests were performed, arterial blood gas measurements were made, and cardiac function and systolic pulmonary artery pressure (SPAP) were assessed by echocardiography. RESULTS: Of 94 patients (31% men, n = 29), 62 patients (66%) had cystic bronchiectasis and 32 patients (34%) had cylindrical bronchiectasis. Right ventricular (RV) systolic dysfunction was observed in 12 patients (12.8%), left ventricular (LV) systolic dysfunction was observed in 3 patients (3.3%), and LV diastolic dysfunction was observed in 11 patients (11.7%); all had cystic bronchiectasis. RV dimensions were significantly greater in the cystic bronchiectasis group, and were positively correlated with SPAP (p < 0.0001) and negatively correlated with Pao2 (p < 0.016). Other hemodynamic variables were not different between groups. PH in 31 patients (32.9%) was significantly greater in patients with cystic bronchiectasis compared with cylindrical bronchiectasis (p = 0.04). In cystic bronchiectasis, SPAP was positively correlated with Paco2 (p = 0.001), and inversely correlated with Pao2 (p = 0.03), diffusion capacity of the lung for carbon monoxide percentage (p = 0.02), and FEV1 (p = 0.02). CONCLUSIONS: RV systolic dysfunction and PH were more common than LV systolic dysfunction in bronchiectatic patients. LV diastolic dysfunction was mainly seen in severe PH. We recommend detailed assessment of cardiac function, particularly LV diastolic function, in patients with bronchiectasis.     

Large and medium-sized pulmonary artery obstruction does not play a role of primary importance in the etiology of sickle-cell disease-associated pulmonary hypertension

BACKGROUND: Pulmonary hypertension (PHT) occurs in approximately 30% of adult patients with sickle-cell disease (SCD) and is a risk factor for early death. The potential role of pulmonary artery obstruction, whether due to emboli or in situ thrombosis, in the etiology of SCD-related PHT is unknown. METHODS: Consecutive SCD patients were screened for PHT (defined as a tricuspid regurgitant jet flow velocity > or = 2.5 m/s) employing echocardiography and were evaluated for pulmonary artery obstruction with ventilation-perfusion (VQ) scintigraphy. RESULTS: Fifty-three HbSS, 6 HbSbeta(0)-thalassemia, 20 HbSC, and 6 HbSbeta(+)-thalassemia patients were included. The overall prevalence of PHT was 41% in HbSS/HbSbeta(0)-thalassemia patients and 13% in HbSC/HbSbeta(+)-thalassemia patients. High-probability VQ defects (Prospective Investigation of Pulmonary Embolism Diagnosis criteria) were detected in two patients, one of whom had PHT. In HbSS/HbSbeta(0)-thalassemia patients with PHT, 19 patients (86%), 2 patients (9%), and 1 patient (5%) had low-, intermediate-, or high-probability scan results as compared to 30 patients (97%), 1 patient (3%), and 0 patients (0%) in HbSS/HbSbeta(0)-thalassemia patients without PHT (p = 0.31). In HbSC/HbSbeta(+)-thalassemia patients with PHT, 3 patients (100%), 0 patients (0%), and 0 patients (0%) had low-, intermediate-, and a high-probability scan as compared to 19 patients (90%), 1 patient (5%), and 1 patient (5%) in HbSC/HbSbeta(+)-thalassemia patients without PHT (p = 0.86). There were no statistical differences in irregular distribution of the radiopharmaceutical or nonspecific signs associated with PHT between patients with and without PHT. CONCLUSIONS: Although small pulmonary artery obstruction cannot be excluded, large to medium-sized pulmonary artery obstruction is an unlikely primary causative factor in SCD-related PHT.     

Six-minute walk test for the evaluation of pulmonary disease severity in scleroderma patients

BACKGROUND: Pulmonary involvement is the leading cause of systemic sclerosis (SSc)-related deaths. A simple test to evaluate exercise capacity is the 6-min walk test (6MWT), and the walk distance is used as a primary outcome in clinical trials. Hemoglobin desaturation during a 6MWT is predictive of mortality in patients with primary pulmonary hypertension. Our objectives were to evaluate the walk distance and resting oxygen saturation - oxygen saturation after the 6-min period (DeltaSat) during the 6MWT in patients with SSc, and to establish correlations between the 6MWT results and other clinical variables. METHODS: We analyzed 110 SSc patients. DeltaSat was defined as a fall of end-of-test saturation >or= 4%. Clinical and demographic data were collected. All the patients were submitted to chest radiographs and high-resolution CT (HRCT) and underwent pulmonary function testing and echocardiography, and the presence of autoantibodies was determined. RESULTS: The variables associated with a walk distance < 400 m (p < 0.05) were age, dyspnea index, fibrosis on radiography, pulmonary arterial systolic pressure (PASP) >or= 30 mm Hg, and desaturation. The variables associated with DeltaSat (p < 0.05) were age, positive anti-Scl-70 autoantibody, dyspnea index, fibrosis on radiography, FVC < 80% of predicted, PASP >or= 30 mm Hg, and ground-glass or reticular opacities on HRCT. In the multivariate logistic regression analysis, three variables were significant when tested with walk distance: age, race, and dyspnea index; four variables were significant when tested with DeltaSat: age, dyspnea index, positive anti-Scl-70 autoantibody, and FVC < 80% of predicted. CONCLUSIONS: Desaturation during a 6MWT provides additional information regarding severity of disease in scleroderma patients with pulmonary manifestations.     

FEV1/FEV6 and FEV6 as an alternative for FEV1/FVC and FVC in the spirometric detection of airway obstruction and restriction

STUDY OBJECTIVES: To evaluate the use of the FEV(1)/forced expiratory volume at 6 s of exhalation (FEV(6)) ratio and FEV(6) as an alternative for FEV(1)/FVC and FVC in the detection of airway obstruction and lung restriction, respectively. SETTING: Pulmonary function laboratory of the Academic Hospital of the Free University of Brussels. PARTICIPANTS: A total of 11,676 spirometric examinations were analyzed on subjects with the following characteristics: white race; 20 to 80 years of age; 7,010 men and 4,666 women; and able to exhale for at least 6 s. METHODS: Published reference equations were used to determine lower limits of normal (LLN) for FEV(6), FVC, FEV(1)/FEV(6), and FEV(1)/FVC. We considered a subject to have obstruction if FEV(1)/FVC was below its LLN. A restrictive spirometric pattern was defined as FVC below its LLN, in the absence of obstruction. From these data, sensitivity and specificity of FEV(1)/FEV(6) and FEV(6) were calculated. RESULTS: For the spirometric diagnosis of airway obstruction, FEV(1)/FEV(6) sensitivity was 94.0% and specificity was 93.1%; the positive predictive value (PPV) and negative predictive value (NPV) were 89.8% and 96.0%, respectively. The prevalence of obstruction in the entire study population was 39.5%. For the spirometric detection of a restrictive pattern, FEV(6) sensitivity was 83.2% and specificity was 99.6%; the PPVs and NPVs were 97.4% and 96.9%, respectively. The prevalence of a restrictive pattern was 15.7%. Similar results were obtained for male and female subjects. When diagnostic interpretation differed between the two indexes, measured values were close to the LLN. CONCLUSIONS: The FEV(1)/FEV(6) ratio can be used as a valid alternative for FEV(1)/FVC in the diagnosis of airway obstruction, especially for screening purposes in high-risk populations for COPD in primary care. In addition, FEV(6) is an acceptable surrogate for FVC in the detection of a spirometric restrictive pattern. Using FEV(6) instead of FVC has the advantage that the end of a spirometric examination is more explicitly defined and is easier to achieve.     

Importance of noninvasively measured respiratory muscle overload among the causes of hospital readmission of COPD patients

AIM: To evaluate the influence of respiratory muscle overload and right cardiac overload among the possible risk factors of hospital readmission in a 1-year follow-up of a cohort of patients with moderate-to-severe COPD. METHODS: A total of 112 COPD patients who were admitted consecutively to the hospital for acute exacerbation. At hospital discharge, we evaluated the conventional clinical and functional determinations in addition to the pressure-time index (PTI), which is obtained using the equation PTI = (Pawo/Pimax) x (Ti/Ttot) x 100, where Pawo represents the mean airway pressure measured at the mouth during spontaneous breathing, Pimax is the maximal inspiratory pressure, Ti is the inspiratory time, and Ttot is the total breathing cycle time. A cardiac echo-Doppler examination was carried out when patients were in stable condition and presented clinical signs of right cardiac overload prior to inclusion in the study. RESULTS: Multivariate analysis showed that the use of long-term oxygen therapy (LTOT) and high PTI (> 0.25) were independently related to the risk of hospital readmission. Patients receiving LTOT had higher Paco(2) (p < 0.05), FEV(1) percent predicted (p < 0.05), FVC percent predicted (p < 0.05), and Pao(2) (p < 0.05), and had higher Paco(2) (p < 0.05). An elevated systolic pulmonary arterial pressure (> 40 mm Hg) was also independently related, but only 28 patients had echo-Doppler data that could be used. CONCLUSIONS: At hospital discharge, noninvasively measured respiratory muscle overload as well as the use of LTOT were associated with an increased risk of hospital readmission for exacerbation in patients with moderate-to-severe COPD.     

A 1-year prospective study of the infectious etiology in patients hospitalized with acute exacerbations of COPD

INTRODUCTION: Infection is a major cause of acute exacerbations of COPD (AECOPDs). We aimed to study the infectious etiology related to AECOPD. METHODS: Patients admitted to an acute care hospital in Hong Kong with an AECOPD were recruited prospectively from May 1, 2004, to April 30, 2005. Sputum samples, nasopharyngeal aspirate (NPA) samples, and paired serology specimens were collected. Spirometry was performed with patients in the stable phase 2 to 3 months after hospital discharge. RESULTS: There were 643 episodes of AECOPD among 373 patients. Their mean age was 75.3 years (SD, 7.9 years) with 307 male patients. The mean FEV(1) was 40.4% predicted (SD, 18.7% predicted), and the mean FEV(1)/FVC ratio was 58.4% (SD, 16.0%). Among sputum samples from the 530 episodes of AECOPD hospital admissions that were saved, 13.0%, 6.0%, and 5.5%, respectively, had positive growth of Haemophilus influenzae, Pseudomonas aeruginosa, and Streptococcus pneumoniae. Among the 505 hospital admissions with patients who had NPA samples saved, 5.7%, 2.3%, 0.8%, and 0.8%, respectively, had influenza A, respiratory syncytial virus (RSV), influenza B, and parainfluenza 3 isolated from viral cultures. Paired serology test results revealed a fourfold rise in viral titers in 5.2%, 2.2%, and 1.4% of patients, respectively, for influenza A, RSV, and influenza B. Very severe airflow obstruction (stable-state spirometry) was associated with a higher chance of a positive sputum culture (FEV(1) >/= 30% predicted, 28.2%; FEV(1) < 30% predicted, 40.4%; p = 0.006). CONCLUSION: H influenzae and influenza A were the most common etiologic agents in patients who were hospitalized with AECOPDs. More severe airflow obstruction was associated with a higher chance of a positive sputum culture finding.     

Absence of relationships between tuberculin responses and development of adult asthma with rhinitis and atopy

OBJECTIVE: To investigate the relationship between tuberculin skin responses and the development of adult asthma, rhinitis, and atopy. METHODS: Two hundred fourteen patients with mild-to-moderate asthma accompanied with rhinitis and 220 normal volunteers underwent a medical history, chest radiography, allergen skin-prick testing (SPT), bovine Mycobacterium tuberculosis vaccine (BCG) scar identification, purified protein derivative (PPD) tuberculin skin testing, serum-total and serum-specific IgE measurements, and bronchial provocation (provocative dose of histamine causing a 20% fall in FEV(1) [PD(20)]). RESULTS: Thirty-one normal volunteers (14.1%) and 168 asthma-rhinitis subjects (78.5%) had one or more positive skin test results (p < 0.0001). Neither the presence of a BCG scar nor a history of BCG vaccination had a significant effect on atopy in either group. The rate of PPD positivity had no statistical difference between atopy and nonatopy in both groups. In multivariate logistic regression analysis, the odds ratio for tuberculin reactivity was not related to the level of serum-total IgE nor to the level of serum-specific IgE to Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF), skin response to DP and DF, and PD(20). Overall, no significant correlations were found between tuberculin skin reactivity and log serum-total IgE or PD(20). CONCLUSION: There is no relationship between history of tuberculosis infection, tuberculin responses, and development of adult bronchial asthma, allergic rhinitis, and atopy. Our study suggests that the protection provided by intradermal BCG vaccination in infants to prevent atopic diseases may be limited in early childhood, when a substantial memory of cellular immune modulation still exists.     

Fade of pulmonary function during residual neuromuscular blockade

OBJECTIVES: A decrement in evoked muscle force with repetitive nerve stimulation (fade) suggests impaired neuromuscular transmission. We tested the hypothesis that fade of pulmonary function, ie, a decrease in values of FVC with the second spirometric maneuver compared to the first maneuver, occurs during impaired neuromuscular transmission. DESIGN: Prospective study. PARTICIPANTS: Six healthy male volunteers. INTERVENTIONS: A series of three consecutive spirometric maneuvers was performed every 5 min in six awake healthy volunteers before, during, and after partial paralysis evoked by rocuronium (0.01 mg/kg IV plus 2 to 8 microg/kg/min). MEASUREMENTS AND RESULTS: We measured FVC, FEV(1), forced inspiratory volume in 1 s (FIV(1)), peak expiratory flow (PEF), and peak inspiratory flow (PIF) by spirometry, and force of adductor pollicis muscle by mechanomyography (train-of-four [TOF] stimulation). A statistically significant fade (reduction of the second maneuver from the first maneuver) of FVC, FEV(1), FIV(1), PEF, and PIF was observed during neuromuscular blockade. With peak relaxation (TOF ratio, 0.5) fade amounted to medians of 10% (interquartile range [IQR], 9 to 23%), 7% (IQR, 2 to 16%), 31 (IQR, 19 to 47%), 9% (IQR, 3 to 24%), and 30% (IQR, 5 to 43%), respectively. A fade of >or= 10% was always associated with a clinically relevant (>or= 10%) FVC reduction from baseline (ie, FVC before rocuronium administration). However, FVC reduction from baseline was still present in 23% of measurements without a relevant FVC fade. CONCLUSIONS: A clinically relevant fall (fade) in FVC from the first to the second value during or after neuromuscular blockade suggests impaired pulmonary function and may be due to muscle paralysis. For this reason, the first (best) FVC value may overestimate pulmonary function and expose the patient to an unidentified risk.     

Lung CT densitometry in systemic sclerosis: correlation with lung function, exercise testing, and quality of life

BACKGROUND: To ascertain if analysis of lung density histograms in thin-section CT was more reproducible than visual assessment of lung changes in systemic sclerosis (SSc), and if such density histogram parameters as mean lung attenuation (MLA), skewness, and kurtosis could more closely reflect pulmonary function as well as exercise and quality of life impairment. METHODS: The intraoperator and interoperator reproducibility of visual and densitometric lung CT analysis in 48 SSc patients examined with CT were evaluated by means of weighted kappa statistics. Univariate and multivariate regression analyses were applied to evaluate the relationship of visual and densitometric CT measurements with functional parameters including functional residual capacity (FRC), FVC, FEV(1), diffusion capacity of the lung for carbon monoxide (Dlco), 6-min walking testing (6MWT), and health-related quality of life questionnaire (QLQ) parameters. RESULTS: The intraoperator and interoperator reproducibility of MLA (intraobserver weighted kappa = 0.97; interobserver weighted kappa = 0.96), skewness (intraobserver weighted kappa = 0.89; interobserver weighted kappa = 0.88), and kurtosis (intraobserver weighted kappa = 0.89; interobserver weighted kappa = 0.88) were higher than those of visual assessment (intraobserver weighted kappa = 0.71; interobserver weighted kappa = 0.69). In univariate analysis, only densitometric measurements were correlated with some exercise and QLQ parameters. In multivariate analysis, MLA (square regression coefficient corrected [R(2)c] = 0.70), skewness (R(2)c = 0.78), and kurtosis (R(2)c = 0.77) were predicted by FRC, FVC, Dlco, 6MWT, and QLQ parameters, while visual assessment was associated only with FRC and FVC (R(2)c = 0.40). CONCLUSIONS: In SSc, densitometric analysis is more reproducible than visual assessment of lung changes in thin-section CT and more closely correlated to pulmonary function testing, 6MWT, and QLQ. Density histogram parameters may be useful for cross-sectional and longitudinal studies of lung involvement in SSc.     

Clinical outcome of patients with upper-extremity deep vein thrombosis: results from the RIETE Registry

BACKGROUND: There is little information on the clinical outcome of patients with upper-extremity deep vein thrombosis (DVT). METHODS: RIETE is an ongoing registry of consecutive patients with objectively confirmed, symptomatic, acute DVT or pulmonary embolism (PE). In this analysis, we analyzed the demographic characteristics, treatment, and 3-month outcome of all patients with DVT in the arm. RESULTS: Of the 11,564 DVT patients enrolled, 512 patients (4.4%) had arm DVT. They presented less often with clinically overt PE (9.0% vs 29%; odds ratio, 0.24; 95% confidence interval [CI], 0.18 to 0.33) than those with lower-limb DVT, but their 3-month outcome was similar. Of the 512 patients with arm DVT, 196 patients (38%) had cancer and 228 patients (45%) had catheter-related DVT. During follow-up, those with cancer DVT had an increased incidence of major bleeding (4.1% vs 0.9%; odds ratio, 4.4; 95% CI, 1.2 to 21), recurrent venous thromboembolism (6.1% vs 2.8%; odds ratio, 2.2; 95% CI, 0.91 to 5.6; p = 0.04), and death (22% vs 3.5%; odds ratio, 7.8; 95% CI, 4.0 to 16). Thirty patients had the composite event of recurrent DVT, symptomatic PE, or major bleeding. They were significantly older, more often had cancer, and presented more frequently with symptomatic PE on hospital admission. On multivariate analysis, only cancer patients with arm DVT had an increased risk for the composite event (odds ratio, 3.0; 95% CI, 1.4 to 6.4). CONCLUSIONS: At presentation, patients with arm DVT have less often clinically overt PE than those with lower-limb DVT, but their 3-month outcome is similar. Among patients with arm DVT, those with cancer have the worse outcome.