Association of breathing sound spectra with glottal dimensions in exercise-induced vocal cord dysfunction.

The objective of this study was to evaluate associations between the breathing sound spectra and glottal dimensions in exercise-induced vocal cord dysfunction (EIVCD) during a bicycle ergometry test. Nineteen subjects (mean age 21.8 years and range 13-39 years) with suspected EIVCD were studied. Vocal folds were continuously imaged with videolaryngoscopy and breathing sounds were recorded during the bicycle exercise test. Twelve subjects showed paradoxical movement of the vocal folds during inspiration by the end of the exercise. In seven subjects, no abnormal reactions in vocal folds were found; they served as control subjects. The glottal quotient (interarytenoid distance divided by the anteroposterior glottal distance) was calculated. From the same time period, the tracheal-vocal tract resonance peaks of the breathing sound spectra were analyzed, and stridor sounds were detected and measured. Subjects with EIVCD showed significantly higher resonance peaks during the inspiratory phase compared to the expiratory phase (p < 0.014). The glottal quotient decreased significantly in the EIVCD group (p < 0.001), but not in the control group. 8 out of 12 EIVCD patients (67%) showed stridor sounds, while none of the controls did. There was a significant inverse correlation between the frequencies of the breathing sound resonance peaks and the glottal quotient. The findings indicate that the typical EIVCD reaction of a paradoxical approximation of the vocal folds during inspiration, measured here as a decrease in the glottal quotient, is significantly associated with an increase in inspiratory resonance peaks. The findings are applicable in the documentation of EIVCD findings using videolaryngoscopy, in addition to giving clinicians tools for EIVCD recognition. However, the study is limited by the small number of subjects.

Radiation dose and image quality in K-edge subtraction computed tomography of lung in vivo.

K-edge subtraction computed tomography (KES-CT) allows simultaneous imaging of both structural features and regional distribution of contrast elements inside an organ. Using this technique, regional lung ventilation and blood volume distributions can be measured experimentally in vivo. In order for this imaging technology to be applicable in humans, it is crucial to minimize exposure to ionizing radiation with little compromise in image quality. The goal of this study was to assess the changes in signal-to-noise ratio (SNR) of KES-CT lung images as a function of radiation dose. The experiments were performed in anesthetized and ventilated rabbits using inhaled xenon gas in O2 at two concentrations: 20% and 70%. Radiation dose, defined as air kerma (Ka), was measured free-in-air and in a 16 cm polymethyl methacrylate phantom with a cylindrical ionization chamber. The dose free-in-air was varied from 2.7 mGy to 8.0 Gy. SNR in the images of xenon in air spaces was above the Rose criterion (SNR > 5) when Ka was over 400 mGy with 20% xenon, and over 40 mGy with 70% xenon. Although in human thorax attenuation is higher, based on these findings it is estimated that, by optimizing the imaging sequence and reconstruction algorithms, the radiation dose could be further reduced to clinically acceptable levels.

Simultaneous in vivo synchrotron radiation computed tomography of regional ventilation and blood volume in rabbit lung using combined K-edge and temporal subtraction.

In K-edge subtraction (KES) imaging with synchrotron radiation computed tomography (SRCT), two images are taken simultaneously using energies above and below the K-absorption edge of a contrast agent. A logarithmic difference image reveals the contrast agent concentration with good accuracy. Similarly, in temporal subtraction imaging (TSI) the reference image is taken before the introduction of the contrast agent. Quantitative comparisons of in vivo images of rabbit lung indicated that similar results for concentrations of iodine in blood vessels and xenon in airways are obtained by KES and TSI, but the level of noise and artifacts was higher in the latter. A linear fit showed that in the lung parenchyma rho(TSI) = (0.97 +/- 0.03)rho(KES) + (0.00 +/- 0.05) for xenon and rho(TSI) = (1.21 +/- 0.15)rho(KES) + (0.0 +/- 0.1) for iodine. For xenon the calculation of time constant of ventilation gave compatible values for both of the methods. The two methods are combined for the simultaneous determination of the xenon concentration (by KES) and the iodine concentration (by TSI) in lung imaging, which will allow simultaneous in vivo determination of ventilation and perfusion.

Quantitative Imaging of Regional Aerosol Deposition, Lung Ventilation and Morphology by Synchrotron Radiation CT.

To understand the determinants of inhaled aerosol particle distribution and targeting in the lung, knowledge of regional deposition, lung morphology and regional ventilation, is crucial. No single imaging modality allows the acquisition of all such data together. Here we assessed the feasibility of dual-energy synchrotron radiation imaging to this end in anesthetized rabbits; both in normal lung (n = 6) and following methacholine (MCH)-induced bronchoconstriction (n = 6), a model of asthma. We used K-edge subtraction CT (KES) imaging to quantitatively map the regional deposition of iodine-containing aerosol particles. Morphological and regional ventilation images were obtained, followed by quantitative regional iodine deposition maps, after 5 and 10 minutes of aerosol administration. Iodine deposition was markedly inhomogeneous both in normal lung and after induced bronchoconstrition. Deposition was significantly reduced in the MCH group at both time points, with a strong dependency on inspiratory flow in both conditions (R2 = 0.71; p < 0.0001). We demonstrate for the first time, the feasibility of KES CT for quantitative imaging of lung deposition of aerosol particles, regional ventilation and morphology. Since these are among the main factors determining lung aerosol deposition, we expect this imaging approach to bring new contributions to the understanding of lung aerosol delivery, targeting, and ultimately biological efficacy.

Mechanism of enhanced insulin sensitivity in athletes. Increased blood flow, muscle glucose transport protein (GLUT-4) concentration, and glycogen synthase activity.

UNLABELLED: We examined the mechanisms of enhanced insulin sensitivity in 9 male healthy athletes (age, 25 +/- 1 yr; maximal aerobic power [VO2max], 57.6 +/- 1.0 ml/kg per min) as compared with 10 sedentary control subjects (age, 28 +/- 2 yr; VO2max, 44.1 +/- 2.3 ml/kg per min). In the athletes, whole body glucose disposal (240-min insulin clamp) was 32% (P < 0.01) and nonoxidative glucose disposal (indirect calorimetry) was 62% higher (P < 0.01) than in the controls. Muscle glycogen content increased by 39% in the athletes (P < 0.05) but did not change in the controls during insulin clamp. VO2max correlated with whole body (r = 0.60, P < 0.01) and nonoxidative glucose disposal (r = 0.64, P < 0.001). In the athletes forearm blood flow was 64% greater (P < 0.05) than in the controls, whereas their muscle capillary density was normal. Basal blood flow was related to VO2max (r = 0.63, P < 0.05) and glucose disposal during insulin infusion (r = 0.65, P < 0.05). The forearm glucose uptake in the athletes was increased by 3.3-fold (P < 0.01) in the basal state and by 73% (P < 0.05) during insulin infusion. Muscle glucose transport protein (GLUT-4) concentration was 93% greater in the athletes than controls (P < 0.01) and it was related to VO2max (r = 0.61, P < 0.01) and to whole body glucose disposal (r = 0.60, P < 0.01). Muscle glycogen synthase activity was 33% greater in the athletes than in the controls (P < 0.05), and the basal glycogen synthase fractional activity was closely related to blood flow (r = 0.88, P < 0.001). IN CONCLUSION: (a) athletes are characterized by enhanced muscle blood flow and glucose uptake. (b) The cellular mechanisms of glucose uptake are increased GLUT-4 protein content, glycogen synthase activity, and glucose storage as glycogen. (c) A close correlation between glycogen synthase fractional activity and blood flow suggests that they are causally related in promoting glucose disposal.

Chronic bronchitis and chronic obstructive pulmonary disease. The Finnish Action Programme, interim report.

The Finnish National Prevention and Treatment Programme for Chronic Bronchitis and COPD, launched in 1998, has, to date, been running for 6 years (2003). The goals of this action programme were to reduce the incidence of COPD and the number of moderate and severe cases of the disease, and to reduce both the number of days of hospitalisation and treatment costs. A prevalent implementation of over 250 information and training events started. Health centres and pharmacies appointed a person in charge of COPD patients. In order to improve the cooperation between primary and specialised care, two thirds of hospital districts created local COPD treatment chains. The early diagnosis of COPD by spirometric examination was activated during the programme. Number of health centres with available spirometric services increased to 95%. Before the start of the programme, approximately 5-9% of the adult population had COPD. During the whole programme, the proportion of male and female smokers decreased from 30% to 26% and from 20% to 19%, respectively. The total number of hospitalisation periods and days due to COPD decreased by 15% and 18%, respectively. Both the number of pensioners and daily sickness days due to COPD also decreased by 18%. Registered COPD induced deaths remained at their previous levels during the monitoring period, i.e. around 1000 deaths out of 5.2 millions annually. The measures recommended by the programme have been widely introduced but they need to be still more effective.

Reference values of spirometry for Finnish adults.

BACKGROUND: Diagnostic assessment of lung function necessitates up-to-date reference values. The aim of this study was to estimate reference values for spirometry for the Finnish population between 18 and 80 years and to compare them with the existing Finnish, European and the recently published global GLI2012 reference values. METHODS: Spirometry was performed for 1380 adults in the population-based FinEsS studies and for 662 healthy non-smoking volunteer adults. Detailed predefined questionnaire screening of diseases and symptoms, and quality control of spirometry yielded a sample of 1000 native Finns (387 men) healthy non-smokers aged 18-83 years. Sex-specific reference values, which are estimated using the GAMLSS method and adjusted for age and height, are provided. RESULTS: The predicted values for lung volumes are larger than those obtained by GLI2012 prediction for the Caucasian subgroup for forced vital capacity (FVC) by an average 6·2% and 5·1% and forced expiratory volume in 1 s (FEV1) by an average 4·2% and 3·0% in men and women, respectively. GLI2012 slightly overestimated the ratio FEV1/FVC with an age-dependent trend. Most reference equations from other European countries, with the exception of the Swiss SAPALDIA study, showed an underestimation of FVC and FEV1 to varying degrees, and a slight overestimation of FEV1/FVC. CONCLUSION: This study offers up-to-date reference values of spirometry for native Finns with a wide age range. The GLI2012 predictions seem not to be suitable for clinical use for native Finns due to underestimation of lung volumes.

Physical fitness and endothelial function (nitric oxide synthesis) are independent determinants of insulin-stimulated blood flow in normal subjects.

Insulin induces vasodilation via stimulation of nitric oxide (NO) synthesis. This action of insulin exhibits considerable interindividual variation. We determined whether the response of blood flow to endothelium-dependent vasoactive agents correlates with that to insulin or whether other factors, such as physical fitness, limb muscularity, or vasodilatory capacity, better explain variations in insulin-stimulated blood flow. Direct measurements of the forearm blood flow response to three 2-h sequential doses of insulin (1, 2, and 5 mU/ kg.min), endothelium-dependent (acetylcholine and NG-monomethyl-L-arginine) and endothelium-independent (sodium nitroprusside) vasoactive agents, and ischemia (reactive hyperemic forearm blood flow) were performed in 22 normal subjects (age, 24 +/- 1 yr; body mass index, 22.2 +/- 0.6 kg/m2; maximal aerobic power, 40 +/- 2 mL/kg.min). The highest insulin dose increased blood flow by 111 +/- 17%. The fraction of basal blood flow inhibited by NG-monomethyl-L-arginine (NO synthesis-dependent flow) varied from 6-47%. Maximal aerobic power (r = 0.52; P < 0.02), the percentage of forearm muscle (r = 0.50; P < 0.02), and the NO synthesis-dependent flow (r = 0.42; P < 0.05), but not reactive hyperemic, acetylcholine-stimulated, or sodium nitroprusside-stimulated flow, were significantly correlated with insulin-stimulated (5 mU/kg.min) blood flow. In multiple linear regression analysis, 52% of the variation (multiple R = 0.72; P < 0.001) in insulin-stimulated blood flow was explained by NO synthesis-dependent flow (P < 0.005) and the percentage of forearm muscle (P < 0.005). We conclude that endothelial function (NO synthesis-dependent basal blood flow) and forearm muscularity are independent determinants of insulin-stimulated blood flow.

Intense physical training decreases circulating antioxidants and endothelium-dependent vasodilatation in vivo.

Physical training increases free radical production and consumes antioxidants. It has previously been shown that acute exercise markedly increases the susceptibility of LDL to oxidation but whether such changes are observed during physical training is unknown. We measured circulating antioxidants, lipids and lipoproteins, and blood flow responses to intrabrachial infusions of endothelium-dependent (acetylcholine, ACh, L-N-monomethyl-arginine, L-NMMA) and -independent (sodium nitroprusside, SNP) vasoactive agents, before and after 3 months of running in 9 fit male subjects. Maximal aerobic power increased from 53 +/- 1 to 58 +/- 2 ml/kg min (P < 0.02). All circulating antioxidants (uric acid, SH-groups, alpha-tocopherol, beta-carotene, retinol) except ascorbate decreased significantly during training. Endothelium-dependent vasodilatation in forearm vessels decreased by 32-35% (P < 0.05), as determined from blood flow responses to both a low (10.8 +/- 2.1 vs. 7.3 +/- 1.5 ml/dl min, 0 vs. 3 months) and a high (14.8 +/- 2.6 vs. 9.6 +/- 1.8) ACh dose. The % endothelium-dependent blood flow (% decrease in basal flow by L-NMMA), decreased through training from 37 +/- 3 to 22 +/- 7% (P < 0.05). Blood flow responses to SNP remained unchanged. The decrease in uric acid was significantly correlated with the change in the % decrease in blood flow by L-NMMA (r = 0.74, P < 0.05). The lag time for the susceptibility of plasma LDL to oxidation in vitro, LDL size and the concentration of LDL cholestetol remained unchanged. We conclude that relatively intense aerobic training decreases circulating antioxidant concentrations and impairs endothelial function in forearm vessels.

Enhancement of radiation effects by alpha interferon in the treatment of small cell carcinoma of the lung.

The effects on lung tissue and tumor of natural human alpha interferon (IFN) and radiotherapy were investigated in a multimodality treatment program for selected patients with small cell carcinoma of the lung (SCLC). Interferon was given first as a single agent, then concomitantly with radiotherapy to 12 previously untreated patients with limited disease. At disease progression outside the chest, interferon was discontinued and combination chemotherapy was initiated. In the first series, 7 patients received a high interferon induction dose (800 X 10(6) IU i.v. over 5 days) followed by low-dose maintenance therapy (6 X 10(6) IU i.m. TIW), median total dose 1380 X 10(6) IU (range 794-2074). At local progression, split-course radiotherapy, 55 Gy/20 F/7 wk, was added to interferon therapy. In the second series, 5 patients received low-dose interferon from the start (6 X 10(6) IU i.m. daily) combined with twice-a-day fractionated radiotherapy 44 Gy/40 F/4 wk. Median total dose of interferon in this series was 698 X 10(6) IU (range 354-828). Tumor response and normal tissue reactions were evaluated by monthly chest X rays, 3-monthly CT scans, restaging bronchoscopies and by serial respiratory function tests. Autopsy specimens from both lungs within and outside the radiation field were systematically evaluated when available. After the completion of radiotherapy, there were 4/7 CR in the high-dose IFN group compared to 3/5 CR in the low-dose IFN group. Rapid shrinkage of huge tumor masses was observed. At 2 months post radiotherapy radiological grade III fibrosis occurred in 4/7 patients in the high-dose and 1/5 patients in the low-dose group. Lung function studies showed a significant decrease in diffusing capacity and in lung volumes. Seven patients died within 12 months from start of interferon treatment, one of them from treatment complication. At autopsy the tumor area was in most cases replaced by severe fibrosis. Outside the radiation field lung fibrosis was mild. Our results suggest enhancement of radiation effect by interferon with a possible dose and/or schedule dependence of interferon and radiotherapy and call for more clinical studies of IFN and radiotherapy in combination.

ATP, phosphocreatine and lactate in exercising muscle in mitochondrial disease and McArdle's disease.

We studied exercise-induced changes in the adenosine triphosphate (ATP), phosphocreatine (PCr), and lactate levels in the skeletal muscle of mitochondrial patients and patients with McArdle's disease. Needle muscle biopsy specimens for biochemical measurement were obtained before and immediately after maximal short-term bicycle exercise test from 12 patients suffering from autosomal dominant and recessive forms of progressive external ophthalmoplegia and multiple deletions of mitochondrial DNA (adPEO, arPEO, respectively), five patients with mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) 3243 A-->G point mutation, and four patients with McArdle's disease. Muscle ATP and PCr levels at rest or after exercise did not differ significantly from those of the controls in any patient group. In patients with mitochondrial disease, muscle lactate tended to be lower at rest and increase more during exercise than in controls, the most remarkable rise being measured in patients with adPEO with generalized muscle symptoms and in patients with MELAS point mutation. In McArdle patients, the muscle lactate level decreased during exercise. No correlation was found between the muscle ATP and PCr levels and the respiratory chain enzyme activity.

Cardiopulmonary evaluation of exercise tolerance after chest irradiation and anticancer chemotherapy in children and adolescents.

OBJECTIVE: The aim of the study was to evaluate the cardiopulmonary exercise tolerance in children and adolescents after chest irradiation and anticancer chemotherapy. METHODS: We studied 30 subjectively asymptomatic patients aged 8 to 25 years treated for pediatric malignancies with chest irradiation (XRT) +/- chemotherapy. The median interval since XRT was 7 (range, 2 to 13) years. The median XRT dose for mediastinum and/or lungs was 2550 (range, 1000 to 5100) cGy. The median cumulative dose of anthracyclines was 250 (range, 0 to 480) mg/m2. Cardiac function and exercise tolerance were evaluated by electrocardiography, echocardiography, radionuclide cineangiography, and exercise test with gas exchange analysis. RESULTS: The patients differed from normal controls in systolic indices of myocardial function. In echocardiography, the left ventricular contractility was abnormal in 14/30 patients. In radionuclide cineangiography, the left ventricular ejection fraction was subnormal in 6/30 patients, and in 9/30 patients the rise in ejection fraction during exercise was inadequate (< 5%). In exercise testing, the mean (+/- SD) maximum workload attained was 2.7 (+/- 0.7) watts/kg, and the mean (+/- SD) maximum oxygen consumption was 35.4 (+/- 9.7) mL/min/kg. Both variables were < 80% of predicted values in 11 patients. CONCLUSIONS: XRT and anticancer chemotherapy very often lead to late cardiopulmonary toxicity and impaired exercise tolerance. Although in most cases this toxicity seemed to be mild and subclinical, the long-term clinical sequels merit further evaluation.

Response of the beta-adrenergic system to maximal dynamic exercise in congestive heart failure secondary to idiopathic dilated cardiomyopathy.

In congestive heart failure (CHF), prolonged exposure to high plasma catecholamine levels may reduce the responsiveness of the adrenergic system to physiologic stimuli. In healthy subjects, exercise is known to induce a rapid up-regulation of lymphocytic beta adrenoceptors. Lymphocytic beta-adrenoceptor density, lymphocytic basal and isoproterenol-stimulated cyclic adenosine monophosphate (cAMP) response, plasma catecholamine concentrations and plasma cAMP levels were studied during maximal ergometer exercise in 11 patients with CHF secondary to dilated cardiomyopathy and in 6 healthy control subjects. At rest, there was no difference in the lymphocytic beta-adrenoceptor levels between the patients and control subjects (48 +/- 3 vs 42 +/- 5 fmol/mg protein, respectively). However, the exercise-induced increase in lymphocytic beta adrenoceptors was attenuated in patients when compared with controls (26 +/- 6 fmol/mg protein [56%] vs 75 +/- 16 fmol/mg protein [204%], respectively, p less than 0.02). A subgroup of 4 patients with the lowest exercise capacity (peak oxygen uptake less than 12.5 ml/min/kg) had even more reduced up-regulation compared with the other 7 patients (13 +/- 1 fmol/mg protein [29%] vs 34 +/- 9 fmol/mg protein [71%], p less than 0.05). The lymphocytic cAMP response at rest and during exercise tended to be lower in patients compared with controls, but the differences did not reach statistical significance. The plasma levels of epinephrine and norepinephrine at rest were higher in patients compared with controls, but no difference was found in the exercise values. The plasma levels of cAMP correlated closely with plasma catecholamine levels at rest, but not during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Differences in acoustic and dynamic characteristics of spontaneous cough in pulmonary diseases.

The aim of this study was to determine whether the flow dynamics and sound spectra of spontaneous cough show characteristic differences in asthma, acute and chronic bronchitis, TBCS and FPD. During the cough, the air flow from the mouth and the sound from the sternal manubrium were simultaneously recorded. The cough sounds were analyzed spectrographically. Peak expiratory flow during cough was significantly lower in asthma than in TBCS, acute bronchitis or FPD. Duration of the first cough sound was longer in asthma than in FPD, TBCS or chronic bronchitis. The number of additional cough sounds was smaller in asthma than in the other conditions. The highest frequency components of cough sound were lower in asthma than in chronic bronchitis or TBCS. The results indicate that pulmonary diseases differ with respect to acoustic and dynamic characteristics of spontaneous cough. This finding may prove useful in the diagnosis of cough.

Effects of weight loss on peak flow variability, airways obstruction, and lung volumes in obese patients with asthma.

STUDY OBJECTIVES: To clarify the pathophysiologic features of the relation between asthma and obesity, we measured the effects of weight reduction on peak expiratory flow (PEF) variability and airways obstruction, compared to simultaneous changes in lung volumes and ventilatory mechanics in obese patients with stable asthma. METHODS: Fourteen obese asthma patients (11 women and 3 men; aged 25 to 62 years) were studied before and after a very-low-calorie-diet period of 8 weeks. PEF variability was determined as diurnal and day-to-day variations. FEV(1) and maximal expiratory flow values were measured with a flow-volume spirometer. Lung volumes, airways resistance (Raw), and specific airways conductance were measured using a constant-volume body plethysmograph. Minute ventilation was monitored in patients in supine and standing positions. RESULTS: As patients decreased their body mass index (SD) from 37.2 (3.7) to 32.1(4.2) kg/m(2) (p < 0. 001), diurnal PEF variation declined from 5.5% (2.4) to 4.5% (1.5) (p = 0.01), and day-to-day variation declined from 5.3% (2.6) to 3. 1% (1.3) (p < 0.005). The mean morning PEF, FEV(1), and FVC increased after weight loss (p = 0.001, p < 0.005, and p < 0.05, respectively). Flow rate at the middle part of FVC (FEF(25-75)) increased even when related to lung volumes (FEF(25-75)/FVC; p < 0. 05). Functional residual capacity and expiratory reserve volume were significantly higher after weight loss (p < 0.05 and p < 0.005, respectively). A significant reduction in Raw was found (p < 0.01). Resting minute ventilation decreased after weight loss (p = 0.01). CONCLUSION: Weight loss reduces airways obstruction as well as PEF variability in obese patients with asthma. The results suggest that obese patients benefit from weight loss by improved pulmonary mechanics and a better control of airways obstruction.

Long-term recording and automatic analysis of cough using filtered acoustic signals and movements on static charge sensitive bed.

Reliable long-term assessment of cough is necessary in many clinical and scientific settings. A new method for long-term recording and automatic analysis of cough is presented. The method is based on simultaneous recording of two independent signals: high-pass filtered cough sounds and cough-induced fast movements of the body. The acoustic signals are recorded with a dynamic microphone in the acoustic focus of a glass fiber paraboloid mirror. Body movements are recorded with a static charge-sensitive bed located under an ordinary plastic foam mattress. The patient can be studied lying or sitting with no transducers or electrodes attached. A microcomputer is used for sampling of signals, detection of cough, statistical analyses, and on-line printing of results. The method was validated in seven adult patients with a total of 809 spontaneous cough events, using clinical observation as a reference. The sensitivity of the method to detect cough was 99.0 percent, and the positive predictivity was 98.1 percent. The system ignored speaking and snoring. The method provides a convenient means of reliable long-term follow-up of cough in clinical work and research.

Effect of physical training on exercise capacity and gas exchange in patients with chronic heart failure.

Decreased exercise capacity is the main factor restricting the daily life of patients with chronic congestive heart failure (CHF). We performed a controlled, randomized study to evaluate the effect of dynamic exercise training of moderate intensity on exercise capacity and gas exchange in patients with CHF. Twenty-seven patients with stable CHF, New York Heart Association (NYHA) functional class II and III, were randomized to training (n = 12) and control (n = 15) groups. During a 3-month period, the training group underwent a supervised physical training program using a bicycle ergometer for 30 min 3 times a week at a load corresponding to 50 to 60% of their peak oxygen consumption. Thereafter, they were advised to continue training at home for the next 3 months. The control group did not change their previous physical activity. A graded maximal exercise test with respiratory gas analysis and an endurance test with constant submaximal workload were performed at baseline and after 3 and 6 months. The exercise endurance increased from 14.7 +/- 2.0 to 27.8 +/- 2.7 min (p < 0.01) and the peak oxygen consumption tended to improve from 19.3 +/- 1.6 to 21.7 +/- 2.3 mL/kg/min (p = 0.09) during the supervised training period. At submaximal workloads, minute ventilation was reduced by 16% per se (p < 0.01) and by 7% in proportion to carbon dioxide production (p < 0.05). Oxygen consumption at the anaerobic threshold increased from 10.5 +/- 0.8 to 12.7 +/- 1.0 mL/kg/min (p < 0.05). The positive training effects were associated with an improvement in the NYHA functional class. The effects of supervised training were preserved during the home-based training period. The results indicate that physical training of moderate intensity significantly improves the exercise capacity and reduces the exaggerated ventilatory response to exercise, particularly at submaximal working levels in patients with CHF. This is associated with alleviation of symptoms.

Averaged and time-gated spectral analysis of respiratory sounds. Repeatability of spectral parameters in healthy men and in patients with fibrosing alveolitis.

STUDY OBJECTIVE: To obtain a basis for assessment of changes in breath sound spectra in patients with pulmonary diseases, short-term and day-to-day repeatability of spectral parameters was studied. DESIGN: Breath sounds were recorded simultaneously from the trachea and from the chest twice at an interval of 15 min (short-term repeatability) and of 1 to 3 days (day-to-day repeatability). During recordings, air flow at the mouth was controlled, the target inspiratory and expiratory peak flow being 1.25 L/s. Inspiratory and expiratory breath sound spectra were averaged over 7 to 10 successive respiratory cycles. The repeatability of sound intensity (RMS), frequency of maximum intensity (Fmax), and median frequency (F50) was analyzed with analysis of variance. PARTICIPANTS: Short-term repeatability was studied in 10 healthy nonsmoking men (age 25 to 44 years), and day-to-day repeatability was studied in 10 healthy nonsmoking men (age 23 to 41 years) and in 12 patients with clinically stable fibrosing alveolitis (age 35 to 82 years). RESULTS: Short-term coefficient of variation (CoV) of Fmax and F50 was 2.6 to 6.7% when recorded from the chest, and 6.2 to 8.7% when recorded from the trachea. Day-to-day CoV of Fmax and F50 in healthy subjects was 4.7 to 8.5% and 5.0 to 8.7% recorded from the chest or from the trachea, respectively. Inspiratory day-to-day variation in those parameters was higher in patients with fibrosing alveolitis. CoV of RMS was high, ranging from 18 to 47% in different subject groups and sampling situations. CONCLUSIONS: Repeatability of F50 of averaged flow-controlled lung sound spectra is good both in healthy subjects and in patients with fibrosing alveolitis. Thus, F50 of respiratory sound spectra may be useful in monitoring of changes induced by respiratory diseases and interventions. These results emphasize the importance of standardization of recording conditions and of analyzing techniques.

Changes in frequency spectra of breath sounds during histamine challenge test in adult asthmatics and healthy control subjects.

Air-flow standardized breath sounds were recorded at the chest and at the trachea during histamine challenge test and after subsequent bronchodilation in 12 asthmatics and 6 healthy controls for spectral analysis, to be compared with simultaneous changes in spirometric variables. Of all the lung sound variables measured, the changes in median frequency of the power spectrum (F50) of tracheal expiratory sounds were found to correlate best (r = 0.853, p < 0.0001) with changes in FEV1. The increase of F50 during histamine challenge was significantly larger in asthmatics than in healthy control subjects (p < 0.005). The provocative dose of histamine inducing a decrease of 15 percent in FEV1 (PD15FEV1) and the provocative dose causing an increase of 30 percent in tracheal expiratory F50 (PD30F50) were significantly related (r = 0.754, p = 0.012). In asthmatics, the breath sound frequency distribution in terms of median frequency reflected acute changes in airways obstruction with high sensitivity and specificity. The present method for breath sound analysis can be applied for patients with limited cooperation during bronchial challenge tests.

Crackles in patients with fibrosing alveolitis, bronchiectasis, COPD, and heart failure.

We have studied the crackling lung sounds of ten patients with cryptogenic fibrosing alveolitis, ten with bronchiectasis, ten with chronic obstructive pulmonary disease, and ten with heart failure by analyzing frequency, waveform, and timing of crackles. The upper frequency limit of inspiratory sounds was higher in CFA than in COPD or in HF. The period of crackling was shorter in COPD than in CFA or BE. Inspiratory crackling terminated significantly earlier in COPD than in CFA, BE, or HF. The initial deflection width and the two-cycle duration of the expanded waveforms of crackles were smaller in CFA than in BE, COPD, or HF. The largest deflection width was smaller in CFA than in BE, HF, or COPD and smaller in BE than in HF. The results indicate that crackling lung sounds in different diseases have distinctive features and that their analysis can be of diagnostic value.