Respiratory muscle function in patients with cystic fibrosis

Respiratory muscle function in patients with cystic fibrosis (CF) can be assessed by measurement of maximal inspiratory pressure (Pi_max), maximal expiratory pressure (Pe_max), and pressure–time index of the respiratory muscles (PTI_mus). We investigated the differences in maximal respiratory pressures and PTI_mus between CF patients with no gross hyperinflation and healthy controls and described the effects of pulmonary function and nutrition impairment on respiratory muscle function in this group of CF patients. Forced expiratory volume in 1 sec (FEV₁), forced vital capacity (FVC) and maximal expiratory flow between 25% and 75% of VC (MEF_25–75), body mass index (BMI), upper arm muscle area (UAMA), Pi_max, Pe_max, and PTI_mus were assessed in 140 CF patients and in a control group of 140 healthy subjects matched for age and gender. Median Pi_max and Pe_max were significantly lower in CF patients compared to the controls [Pi_max = 74 (57–94) in CF vs. 84 (66–102) in controls, P = 0.009], [Pe_max = 71 (50–95) in CF vs. 84 (66–102) in controls, P < 0.001]. Median PTI_mus in CF patients compared to controls was significantly increased [PTI_mus = 0.110 (0.076–0.160) in CF vs. 0.094 (0.070–0.137) in controls, P = 0.049] and it was significantly higher in CF patients with impaired pulmonary function. In CF patients, PTI_mus was significantly negatively related to upper arm muscle area (r = 0.184, P = 0.031). These findings suggest that CF patients with no severe lung disease compared to healthy subjects exhibit impaired respiratory muscle function, while CF patients with impaired pulmonary function and nutrition indices exhibit higher PTI_mus values. Pediatr Pulmonol. 2013; 48:865–873. © 2012 Wiley Periodicals, Inc.     

Air trapping: The major factor limiting diaphragm mobility in chronic obstructive pulmonary disease patients

Background and objective:   Patients with COPD can have impaired diaphragm mechanics. A new method of assessing the mobility of the diaphragm, using ultrasound, has recently been validated. This study evaluated the relationship between pulmonary function and diaphragm mobility, as well as that between respiratory muscle strength and diaphragm mobility, in COPD patients.
Methods:   COPD patients with pulmonary hyperinflation ( n  = 54) and healthy subjects ( n  = 20) were studied. Patients were tested for pulmonary function, maximal respiratory pressures and diaphragm mobility using ultrasound to measure the craniocaudal displacement of the left branch of the portal vein.
Results:   COPD patients had less diaphragm mobility than did healthy individuals (36.5 ± 10.9 mm vs 46.3 ± 9.5 mm, P  = 0.001). In COPD patients, diaphragm mobility correlated strongly with pulmonary function parameters that quantify air trapping (RV: r  = −0.60, P  < 0.001; RV/TLC: r  = −0.76, P  < 0.001), moderately with airway obstruction (FEV₁: r  = 0.55, P  < 0.001; airway resistance: r  = −0.32, P  = 0.02) and weakly with pulmonary hyperinflation (TLC: r  = −0.28, P  = 0.04). No relationship was observed between diaphragm mobility and respiratory muscle strength (maximal inspiratory pressure: r  = −0.11, P  = 0.43; maximal expiratory pressure: r  = 0.03, P  = 0.80).
Conclusion:   The results of this study suggest that the reduction in diaphragm mobility in COPD patients is mainly due to air trapping and is not influenced by respiratory muscle strength or pulmonary hyperinflation.     

Correlation between digital clubbing and pulmonary function in cystic fibrosis

The correlation between digital clubbing and certain pulmonary function derangements (hypoxemia and FEV(1)) was previously described. However, the relationship between digital clubbing and other measures of pulmonary function or the presence of liver disease in patients with cystic fibrosis (CF) is poorly defined. Hence we compared the digital clubbing index (CI: ratio of distal phalangeal depth to interphalangeal depth) of 100 patients with CF (43 males, 57 females; mean age, 15.7 +/- 7.3 years) with that of 100 age- and gender-matched healthy controls. Digital clubbing was defined as a CI > or = 1.00 (mean + 2.6 SD; 99% of normal subjects). The CI and its relationship to pulmonary function and to liver disease was then evaluated in the CF patients. Digital clubbing was present in 75/100 (75%) of CF patients but was absent in all controls (P < 0.0001). In CF patients, CI was inversely correlated with PaO(2) (r = -0.555; P < 0.001), FEV(1) (r = -0.499; P < 0.001), and FEF(25-75%) (r = -0.404; P < 0.001), and was positively correlated with RV (r = 0.285; P < 0.05) and the slope of phase 3 of single-breath nitrogen washout (SP3N(2)) (r = 0.532; P < 0.01). There was no significant correlation between CI and age (r = 0.020; P = 0.84), TLC (r = -0.097; P = 0.34), PaCO(2) (r = 0.167; P = 0.10), or history of liver disease (P = 0.08). We conclude that in CF, the degree of digital clubbing is related to degree of hypoxemia, airways obstruction, hyperinflation, and nonuniformity of ventilation.     

Timing and driving components of the breathing strategy in children with cystic fibrosis during exercise

The aim of this study was twofold: first, to determine the breathing strategies of children with cystic fibrosis (CF) during exercise, and secondly, to see if there was a correlation with lung function parameters. We determined the tension-time index of the inspiratory muscles (T(T0.1)) during exercise in nine children with CF, who were compared with nine healthy children with a similar age distribution. T(T0.1) was determined as followed T(T0.1) = P0.1/PImax . T(I)/T(TOT), where P0.1 is mouth occlusion pressure, PImax is maximal inspiratory pressure, and T(I)/T(TOT) is the duty cycle. CF children showed a significant decrease of their forced expiratory volume in 1 sec (FEV1), forced vital capacity (FCV), and FEV1/FVC, whereas the residual volume to total lung capacity ratio (RV/TLC) ratio and functional residual capacity (FRC) were significantly increased (P < 0.001). Children with CF showed mild malnutrition assessed by actual weight expressed by percentage of ideal weight for height, age, and gender (weight/height ratio; 82.3 +/- 3.6%). Children with CF showed a significant reduction in their PImax (69.3 +/- 4.2 vs. 93.8 +/- 7 cmH2O). We found a negative linear correlation between PImax and weight/height only in children with CF (r = 0.9, P < 0.001). During exercise, P(0.1), P0.1/PImax, and T(T0.1) were significantly higher, for a same percent maximal oxygen uptake in children with CF. On the contrary, T(I)/T(TOT) ratio was significantly lower in children with CF compared with healthy children. At maximal exercise, children with CF showed a T(T0.1) = 0.16 vs. 0.14 in healthy children (P < 0.001). We observed at maximal exercise that P0.1/PImax increased as FEV1/FVC decreased (r = -0.90, P < 0.001), and increased as RV/TLC increased (r = 0.92, P < 0.001) only in children with CF. Inversely, T(I)/T(TOT) decreased as FEV1/FVC decreased (r = 0.89, P < 0.001), and T(I)/T(TOT) decreased as RV/TLC increased (r = -0.94, P < 0.001). These results suggest that children with CF adopted a breathing strategy during exercise in limiting the increase of the duty cycle. Two determinants of this strategy were degrees of airway obstruction and hyperinflation.     

Determinants of the tension-time index of inspiratory muscles in children with cystic fibrosis

Nutritional status and chronic pulmonary hyperinflation can alter respiratory muscle function in cystic fibrosis (CF). This study investigated: 1) whether inspiratory muscle function is reduced in children with stable CF in comparison with healthy controls; and 2) the mechanisms leading to inspiratory muscle weakness, which probably predispose to respiratory muscle fatigue. We determined the tension-time index of the inspiratory muscles (T_TMUS) noninvasively at rest in 16 children with mild to moderate CF (mean age, 11 ± 2 years) and 10 healthy controls (mean age, 11 ± 2 years). The T_TMUS was determined as follows: T_TMUS = T_I/T_TOT · P_I/P_IMAX, where P_I is the mean inspiratory pressure estimated from the measure of mouth occlusion pressure (P0.1), P_IMAX is the maximal inspiratory pressure, and T_I/T_TOT is the duty cycle. The results showed similar nutritional status in both groups, as well as mild to moderate airway obstruction, hyperinflation, and trapped gas in the CF group. In this group only, a significant inverse relationship was found between T₁/T_TOT and P₁/P_IMAX[T_IT_TOT = 0.482 - (0.388P_I/P_IMAX), r = −0.53; p < 0.05]. The patients also had a greater T_TMUS (T_TMUS = 0.087 ± 0.030 in CF vs. 0.056 ± 0.014 in controls, P < 0.01) that increased with decreasing lean body mass (r = −0.70, P < 0.005), with increasing percent predicted functional residual capacity (r = 0.70, P < 0.05). and increasing volumes of trapped gas (r = 0.77, P < 0.01). The multiple linear regression analysis for these factors was significant (R² = 0.84, P < 0.01); however, the partial regression coefficient was significant only for lean body mass (r² = 0.60, P < 0.05). Therefore, muscle mass appeared as the strongest determinant of T_TMUS in CF. This study used a noninvasive method to assess the inspiratory muscle performance in children with CF. The results suggest impairment in inspiratory muscle function in these children despite good nutritional status and only mild to moderate alteration in pulmonary function tests. In addition, we were able to investigate some of the determinants of inspiratory muscle weakness, namely, muscle mass, hyperinflation, and trapped gas, and found that muscle mass played a predominant role. Pediatr. Pulmonol. 1997; 23:336–343. © 1997 Wiley-Liss, Inc.     

Weakness of expiratory muscles and pulmonary complications in malnourished patients undergoing upper abdominal surgery

Background and objective: Malnutrition is prevalent in hospitalized patients and causes systemic damage including effects on the respiratory and immune systems, as well as predisposing to infection and increasing postoperative complications and mortality. This study aimed to assess the impact of malnutrition on the rate of postoperative pulmonary complications, respiratory muscle strength and chest wall expansion in patients undergoing elective upper abdominal surgery. Methods: Seventy‐five consecutive candidates for upper abdominal surgery (39 in the malnourished group (MNG) and 36 in the control group (CG)) were enrolled in this prospective controlled cohort study. All patients were evaluated for nutritional status, respiratory muscle strength, chest wall expansion and lung function before surgery. Postoperative pulmonary complications (pneumonia, tracheobronchitis, atelectasis and acute respiratory failure) before discharge from hospital were also evaluated. Results: The MNG showed expiratory muscle weakness (MNG 65 ± 24 vs CG 82 ± 22 cm H₂O; P < 0.001) and decreased chest wall expansion (P < 0.001), whereas inspiratory muscle strength and lung function were preserved (P > 0.05). The MNG also had a higher incidence of postoperative pulmonary complications compared with the CG (31% and 11%, respectively; P = 0.05). In addition, expiratory muscle weakness was correlated with BMI in the MNG (r = 0.43; P < 0.01). The association between malnutrition and expiratory muscle weakness increased the likelihood of postoperative pulmonary complications after upper abdominal surgery (P = 0.02). Conclusions: These results show that malnutrition is associated with weakness of the expiratory muscles, decreased chest wall expansion and increased incidence of pulmonary complications in patients undergoing elective upper abdominal surgery.     

Predicting sleep-disordered breathing in patients with cystic fibrosis

STUDY OBJECTIVES: To examine predictors of sleep-disordered breathing in patients with cystic fibrosis (CF) and moderate-to-severe lung disease using a comprehensive evaluation of both sleep and daytime function. DESIGN: Cross-sectional analysis of sleep studies, lung function, respiratory muscle strength, and evening and morning arterial blood gas measurements in patients with stable CF. A questionnaire addressing sleep quality was administered. Forward stepwise regression analysis was used to identify the parameters that best predict sleep-related desaturation, hypercapnia, and respiratory disturbance. SETTING: Sleep investigation unit and lung function laboratory. PATIENTS: Thirty-two patients with CF and FEV(1) < 65% predicted, in stable clinical condition. Patients were aged 27 +/- 8 years (mean +/- 1 SD) with FEV(1) of 36 +/- 10% predicted, evening PaO(2) of 68 +/- 8 mm Hg, and PaCO(2) of 43 +/- 5 mm Hg. RESULTS: Evening PaO(2) (p < 0.0001) and morning PaCO(2) (p < 0.01) were predictive of the average minimum oxyhemoglobin saturation per 30-s epoch of sleep (r(2) = 0.74; p < 0.0001). Evening PaO(2) (p < 0.001) was predictive of the rise in transcutaneous carbon dioxide (TcCO(2)) seen from non-rapid eye movement (NREM) to rapid eye movement (REM) sleep (r(2) = 0.37; p < 0.001). In addition, there was some relationship between expiratory respiratory muscle strength and the REM respiratory disturbance index (r(2) = 0.22; p < 0.01). CONCLUSION: Evening PaO(2) was found to contribute significantly to the ability to predict both sleep-related desaturation and the rise in TcCO(2) from NREM sleep to REM sleep in this subgroup of patients with CF.     

Left ventricular diastolic function and cardiac performance during exercise in patients with acromegaly

Exercise-induced impairment of left ventricular (LV) ejection fraction is common in patients with acromegaly and normal resting systolic function. This study aimed to clarify whether diastolic dysfunction plays a role in the abnormal adaptation to exercise in these patients. Forty-eight patients with active acromegaly underwent LV radionuclide angiography at rest and during exercise. Doppler echocardiography was also performed to assess LV mass index and diastolic function by combined analysis of mitral and pulmonary flow velocity curves. LV ejection fraction at peak exercise was related to rest ejection fraction (r = 0.78; P < 0.001), peak filling rate (r = 0.55; P < 0.01), LV mass index (r = -0.56; P < 0.001), and the difference between duration of diastolic reverse pulmonary vein flow and mitral flow at atrial contraction (Delta duration) (r = -0.54; P < 0.01). At stepwise regression analysis, rest ejection fraction and Delta duration were the only variables that independently influenced (P < 0.001) ejection fraction at peak exercise. Diastolic dysfunction is important in determining cardiac performance during exercise in patients with acromegaly and normal resting systolic function. Combined analysis of pulmonary vein and mitral flow velocity curves allows the identification of impaired LV diastolic function in such patients.     

Inspiratory force reserve of the respiratory muscles in children with chronic obstructive pulmonary disease

The purpose of this study was to evaluate inspiratory muscle force reserve in children with chronic obstructive pulmonary disease (COPD). In 15 hyperinflated (FRC/TLC, 65 +/- 0.7%) children, maximal mouth inspiratory static pressure (PImax) at FRC, mouth occlusion pressure (P0.1), tidal volume (VT), inspiratory time (TI), and total duration of the respiratory cycle (Ttot) were all measured. It was found that PImax at FRC was reduced compared with predicted values. However, after lung volume correction, PImax was in the normal range, and P0.1 was higher, TI was shorter, and Ti/Ttot was lower than predicted. The estimated mean inspiratory pressure for breathing at rest (PI) was significantly higher than predicted and was related to total pulmonary resistance (r = 0.74, p less than 0.001). The fraction of PImax developed by the respiratory muscles for breathing at rest (PI/PImax) significantly increased. The higher the PI/PImax ratio, the more the TI/Ttot ratio decreased (r = -0.64, p = 0.01). At rest, our subjects had to develop a mean inspiratory power (W) of as much as 48% (range, 30 to 76%) of the critical W above which fatigue occurs. Thus, even minimal increases in breathing load might expose children with COPD to respiratory muscle fatigue and to respiratory failure.     

Oxidative stress and lipid-derived inflammatory mediators during acute exacerbations of cystic fibrosis

BACKGROUND AND OBJECTIVE: In cystic fibrosis (CF) very few studies have assessed sputum 8-iso-PGF2alpha levels during pulmonary exacerbations as a direct measure of airway oxidative stress. The role of other lipid-derived inflammatory mediators, such as the cysteinyl leukotrienes (cys-LTs) and prostaglandin (PG)-E2, during exacerbations is also poorly defined and the effect of conventional antibiotic therapy on these components of the inflammatory process is unclear. METHODS: Sputum 8-iso-PGF2alpha, total cys-LT and PGE2 levels were measured in 17 CF patients experiencing a pulmonary exacerbation and repeated analysis were performed in 15 of these patients after antibiotic treatment. Eight stable CF and nine healthy subjects provided control data. RESULTS: Sputum 8-iso-PGF2alpha was significantly elevated in acute, but not stable CF patients versus healthy controls (P < 0.001). Similarly, sputum cys-LT and PGE2 levels were increased in acute compared with stable CF patients and healthy controls (P 相似文献   

Assessing the usefulness of outcomes measured in a cystic fibrosis treatment trial

Forced expiratory volume in 1s (FEV(1)) is the usual primary outcome variable in clinical trials in cystic fibrosis (CF). Usually, several secondary outcomes are also measured. We assessed which secondary outcomes are likely to give additional clinically useful information about treatment effects, in order to inform the design of future studies. The study was performed as part of a trial comparing daily rhDNase with alternate day rhDNase and hypertonic saline in CF. The primary outcome was FEV(1). Secondary outcomes were forced vital capacity (FVC), forced expiratory flow at 25-75% of forced vital capacity (FEF(25-75)), number of pulmonary exacerbations, weight gain, quality of life (QOL), and exercise tolerance. The usefulness of each secondary outcome was investigated by assessing if the change in that outcome over the treatment period could be predicted from the primary outcome. Change in FEV(1) correlated with changes in FVC (r(2)=0.76, P=0.001), FEF(25-75) (r(2)=0.64, P=0.001), weight (r(2)=0.08, P=0.001), and change in oxygen saturation with exercise (r(2)=0.08, P=0.001). However, it did not correlate with changes in visual analogue score (VAS) with exercise, QOL, nor with the occurrence of pulmonary exacerbations. Only the outcomes QOL and VAS with exercise actually provided additional information to FEV(1) in this study.     

Human metapneumovirus and respiratory syncytial virus infections in older children with cystic fibrosis

BACKGROUND: Human metapneumovirus (hMPV) has been isolated from children with acute respiratory infection worldwide. Its epidemiology remains to be defined in children with cystic fibrosis (CF). We describe the epidemiology and clinical impact of hMPV in CF children and compared it to respiratory syncytial virus (RSV). METHODS: CF children ages 7-18 years were studied prospectively during the 1998 -1999 RSV season. Nasopharyngeal specimens were collected during acute respiratory illnesses and tested for respiratory viruses. Blood specimens were drawn early, mid, and end of the RSV season, and tested for serological evidence of hMPV and RSV infections. Rates of lower respiratory tract illnesses (LRTI) and hospitalizations for pulmonary exacerbations were compared during the time intervals they developed serological evidence of infection to their non-infection intervals. RESULTS: Six of 44 CF children had a virus positive respiratory illness in 56 LTRI events and 18 hospitalizations. Serological evidence of hMPV and RSV infections occurred in 16 and 20 CF children, respectively; 8 had infections with both viruses. A greater proportion of CF children had >or=1 LRTI during their infection intervals compared to their non-infection intervals (13/25 vs. 5/25; P=0.03). A trend for higher rates of LRTI was observed in the infection intervals compared to non-infection intervals (9.5 +/- 11.0 vs. 4.2 +/- 9.9 per 1,000 child-days; P=0.06), and it was significantly greater with a more conservative estimate (one event per child per interval; 7.4 +/- 7.7 vs. 2.6 +/- 5.4 per 1,000 child-days; P 相似文献   

慢性阻塞性肺疾病患者运动能力与其呼吸驱动及呼吸肌功能关系的研究

目的探究慢性阻塞性肺疾病（COPD）患者运动能力与呼吸驱动及呼吸肌功能之间的关系。方法对28例COPD患者和26名正常对照者分别检测静息常规肺功能、肺弥散功能（DLCO）、口腔阻断压（P0.1）、最大吸气压（PImax）及最大呼气压（PEmax）,并进行运动负荷试验观测氧耗量（VO2）、二氧化碳产生量（VCO2）、分钟通气量（E）、潮气量（T）等气体代谢指标,同时记录受试者运动中的呼吸困难指数（BorgScale）。运动负荷前、后检测动脉血气分析。结果（1）COPD组患者PImax（40±15）mmHg明显低于正常人组（53±19）mmHg（P<0.05）,PEmax在两组中差异无显著性（P>0.05）,COPD组患者P0.1（2.8±0.9）mmHg明显高于正常人组（2.0±0.7）mmHg（P<0.05）,P0.1/PImax（0.069±0.021）也明显高于正常人组（0.037±0.009）（P<0.01）。（2）COPD组患者VO2max与P0.1及PImax未发现明显的相关关系（P>0.05）,但与P0.1/PImax明显正相关（r=0.66,P<0.01）,BorgScale与P0.1/PImax明显正相关（r=0.49,P<0.05）。结论COPD患者运动能力下降除与气道阻塞程度及气体交换障碍等有关外,呼吸驱动相对增高及呼吸肌功能障碍也是其运动能力的限制因素。     

慢性阻塞性肺疾病患者静息能量与呼吸力学及气体交换关系的研究

目的　探究慢性阻塞性肺疾病 (COPD)患者静息能量消耗 (REE)与肺通气功能、呼吸驱动及呼吸肌功能间的关系。方法　用canopy法间接测定 2 6例COPD患者和 2 1例健康对照者的REE、氧耗量 ( VO2 )、二氧化碳产生量 ( VCO2 )及呼吸商 (RQ)。同时测静息肺通气功能、口腔阻断压(P0 1)、最大吸气压 (PIMAX)及最大呼气压 (PEMAX) ,并进行动脉血气分析。结果　 (1)COPD组患者REE实测值 [(15 77 6 9± 311 31)kcal/d]较健康对照组 [(1388 2 9± 194 89)kcal/d]高 (P <0 0 5 ) ;PIMAX[(44 5 3± 10 6 0 )mmHg]较健康对照组 [(71 4 3± 2 2 34)mmHg]低 (P <0 0 1) ,P0 1/PIMAX(0 0 6 8± 0 0 2 6 )较健康对照组 (0 0 39± 0 0 14 )高 (P <0 0 5 ) ;第 1秒钟用力呼气容积 (FEV1)占预计值的百分比 [(5 0 4 6± 2 1 35 ) % ]、动脉血氧分压 (PaO2 ) [(77 72± 8 84 )mmHg]、动脉血氧饱和度(SaO2 ) [(92 5 4± 2 5 5 ) % ]均较健康对照组低 (P <0 0 1) ;心率 [(83 4 6± 11 36 )次 /min]较健康对照组 [(6 9 71± 5 73)次 /min]高 (P <0 0 5 )。 (2 )相关分析显示 ,COPD组REE实测值与身高、体重、体重指数、P0 1/PIMAX及心率呈正相关 (r分别为 0 5 7、0 6 5、0 6 2、0 4 1、0 5 1) ,与FEV1占预计     

Long-term pulmonary morbidity in survivors of congenital diaphragmatic hernia

Our objective was to study long-term respiratory outcomes of congenital diaphragmatic hernia (CDH) treated in the perinatal period. This was a cohort study with 26 adolescent survivors and age- and gender-matched controls. Medical histories were retrieved from hospital charts and questionnaires. Pulmonary function testing included measurement of maximum inspiratory and expiratory pressures (MIPS and MEPS) and maximum voluntary ventilation (MVV). Unpaired two-tailed t-test and nonlinear regression were used for statistical analysis. Significant differences were found in forced expiratory volume in one second (FEV(1)) (79% +/- 16% vs. 94% +/- 10%, P < 0.001), FEF(25-75) (62% +/- 24% vs. 84% +/- 15%, P < 0.001), FRC (114% +/- 20% vs. 95% +/- 13%, P < 0.001), RV/TLC (31% +/- 10% vs. 22% +/- 6%, P < 0.001), MVV (74% +/- 16% vs. 90% +/- 13%, P < 0.001), and MIPS (69% +/- 19% vs. 84% +/- 16%, P < 0.01), with numbers indicating percent predicted of reference values +/- SD. Reduction of MVV was not independent from FEV1 (r = 0.83). Forty-eight percent of patients vs. 4% of controls showed significant improvement of FEV1 after bronchodilators (86% +/- 15 vs. 98% +/- 10, P < 0.01). Forty-six percent of patients had abnormalities of the chest wall or spinal column such as pectus excavatum, pectus carinatum, and scoliosis, mostly mild or moderate. In conclusion, long-term respiratory outcome in adolescent CDH is associated with mild to moderate airway obstruction, a high prevalence of response to bronchodilators, and decreased inspiratory muscle strength. This should guide follow-up scheduling and should be taken into account for perioperative and critical care management.     

Inflammatory markers of lung disease in adult patients with cystic fibrosis

BACKGROUND: Progressive pulmonary disease associated with chronic bacterial infection and inflammation is the major cause of morbidity and mortality in cystic fibrosis (CF) patients. Identifying markers of inflammation that correlate with lung injury may be useful in monitoring disease progression and response to therapy. We hypothesized that levels of serum biomarkers would correlate with clinical course of CF as defined by pulmonary function testing (FEV1). OBJECTIVE: To determine whether biomarkers of systemic inflammation correlate with lung function in adults with CF. METHODS: Retrospective cross-sectional analysis of 63 individuals > or = 30 years of age diagnosed with CF in childhood and followed at Children's Hospital, Boston. We collected data on demographics, CFTR genotype, percent predicted forced expiratory volume in 1 sec (FEV1), C-reactive protein (CRP), serum IgE nd IgG, alpha1-antitrypsin, total white blood cell and neutrophil counts, and percent neutrophils. We used univariate analyses and multivariate linear regression modeling to examine whether markers of systemic inflammation varied with FEV1 (% predicted). RESULTS: In two-covariate models including CRP and one other marker, CRP (P < 0.001) and IgG (P = 0.02) were significantly associated with FEV1 (% predicted). In the CRP and IgG model, percent predicted FEV1 decreased by 4.91% (P < 0.0001) for each twofold increase in CRP and by 1.56% (P = 0.02) for each 100 mg/dl increase in IgG. Results were unchanged by adjustment for number of DF 508 CFTR alleles. There was no association between any other marker and FEV1 (% predicted) after adjusting for CRP. CONCLUSION: Severity of lung disease in long surviving adult CF patients is correlated with CRP and IgG levels. Our findings relating CRP and IgG levels and lung function provide a foundation for subsequent longitudinal studies and consideration of novel disease mechanisms and outcome measurements.     

Spirometry is affected by intelligence and behavior in Duchenne muscular dystrophy

Children with Duchenne muscular dystrophy (DMD) have progressive respiratory muscle weakness. Spirometry monitors progress, but is effort-dependent. Intelligence quotients (IQ) average one standard deviation below normal, and behavioral disturbance is common. Our aim was to assess if impaired intelligence or behavior influences spirometry in children with DMD, and if computerized visual incentives (CVI) are beneficial. Forty-seven boys with DMD, of mean age 12.6 years (range, 6-19), were recruited. Full-scale, performance, and verbal IQ, and parent-and-teacher-reported oppositional behavior scores, were recorded. Each was divided into moderate, mild, and no impairment groups. A randomized crossover design was applied to performing spirometry with or without CVI first. A Jaeger Masterscope (version 4.60) was used. Linear regression defined the relationship between spirometry and both IQ and behavior scores. The paired Student's t- test compared spirometry performed with and without CVI for the overall group and subgroups. Boys with DMD can adequately perform spirometry. There is an association between %FEV1 and %FVC with full-scale (r = 0.50, P = 0.002; r = 0.49, P = 0.003, respectively), performance (r = 0.68, P < 0.0005; r = 0.68, P < 0.0005, respectively) and verbal (r = 0.39, P = 0.043; r = 0.36, P = 0.037, respectively) IQ, but not with parent (P = 0.77, P = 0.70, respectively) or teacher (P = 0.90, P = 0.90, respectively)-reported oppositional behavior scores. The effect of CVI was significant in those with moderate full-scale (P = 0.03), performance (P = 0.002), and verbal (P = 0.02) intellectual impairment, and moderately severe teacher-reported oppositional behavior (P = 0.02). In conclusion, spirometry results are related to intelligence in DMD. Using CVI improves the FVC obtained in those with moderate intellectual or behavioral impairment.     

义诊在轻中度呼吸困难管理中的应用探讨

目的 探讨呼吸疾病义诊形式在轻中度呼吸困难管理中的价值及相关资料分析.方法 借助“世界哮喘日”与“世界COPD日”集中宣教契机,组织呼吸疾病义诊,服务轻中度呼吸困难人群并收集近5年来参加义诊者556人次的临床资料,包括年龄、体质量指数(BMI)、吸烟指数、肺功能(FVC％ pred、FEV1％ pred)、血压、心率、血氧饱和度、心率血压乘积(rate-pressure product,RPP)等,应用SPSS软件进行统计分析.结果 肺通气功能不全比例69.78％,以混合性通气功能障碍表现为主,FEV1％ pred中重度减退者可达45.10％;除BMI和心率外,其他指标均呈现出性别差异,即女性组FEV1％ pred、FVC％ pred(t值分别为2.244、2.459,P值均＜0.05)及SPO2(Z=-3.665,P＜0.01)高于男性组,差异有统计学意义;男性组年龄、收缩压、舒张压、吸烟指数显著高于女性组(Z值分别为-3.903、-2.969、-2.742、-11.481,P值均＜0.01);女性组RPP与FEV1％ pred呈负相关(r=-0.134,P＜0.05),与FVC％ pred呈显著负相关(r=-0.168,P＜0.01);而男性组RPP与FVC％ pred、FEV1％ pred均无明显相关性(r值分别为-0.102、-0.066,P值均＞0.05).结论 在近阶段尚无就医计划的轻中度呼吸困难人群管理中要重视性别差异,采用呼吸疾病义诊形式进行健康宣教,可使相应群体获益.     

Home versus hospital intravenous antibiotic therapy for acute pulmonary exacerbations in children with cystic fibrosis

To compare the effectiveness of home versus hospital intravenous (IV) antibiotic therapy for acute pulmonary exacerbations in children with cystic fibrosis (CF). A retrospective chart review was performed of 143 encounters for pulmonary exacerbations in 50 patients with CF. All encounters were categorized into two groups based on location of completion of antibiotic therapy: hospital group completed treatment in hospital (n = 64), home group completed treatment at home (n = 79). Percent change was calculated for forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), forced expiratory flow rate between 25 percent and 75 percent of vital capacity (FEF(25-75%)), maximum forced expiratory flow (FEF(max)), oxygen saturation (O2 SAT), and weight. Means of percent change (PC) from the beginning to the end of IV antibiotic treatment in outcome variables were compared. Total duration of treatment was compared between the two groups. The two groups had no significant differences at baseline in all outcome variables. Treatment of exacerbations in both groups resulted in significant improvement of lung function, O2 SATS, and weight (P 相似文献   

Skeletal muscle dysfunction in patients with idiopathic pulmonary arterial hypertension

Dyspnea and exercise limitation are common in patients with idiopathic pulmonary arterial hypertension (IPAH). Recently, a reduction in inspiratory and expiratory muscle strength has been observed in IPAH. However, it has not been investigated whether this respiratory muscle weakness might be part of a general muscle dysfunction as observed in congestive left heart failure. Therefore, in 24 consecutive IPAH patients (16 female; age 58.7+/-16.2; WHO class II-III; systolic pulmonary artery pressure during echocardiography at rest (sPAP) 65.0+/-20.6 mmHg, and 6-min-walk test (6-MWT) 473.6+/-127.7 m), the maximal isometric forearm muscle strength (best of three hand grip manoeuvres), maximal inspiratory and expiratory mouth occlusion pressures (Pimax, Pemax) were prospectively evaluated. The isometric forearm muscle strength was significantly lower in IPAH patients (281.7+/-102.6N) than in matched 24 healthy controls (397.1+/-116.8 N; p=0.03). In IPAH patients, there was a correlation between maximal isometric forearm muscle strength and 6-MWT (r=0.67; p=0.0007) and both, Pimax (r=0.69; p=0.0003) and Pemax (r=0.63; p=0.01), respectively. There was no correlation between forearm muscle strength and sPAP (r=0.30; p=0.16). The present skeletal muscle dysfunction is a novel finding in patients with IPAH. The correlation with respiratory muscle dysfunction and severity of disease might indicate a generalised "myopathy" in IPAH.