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At least 217 records · Page 12Linked to original sources
PubMed1993

Pattern of lung volumes in patients with sighing breathing.

BACKGROUND: Sighing breathing is observed in subjects suffering from anxiety with no apparent organic disease. METHODS: Lung volumes and expiratory flow rates were measured in 12 patients with a sighing pattern of breathing and in 10 normal subjects matched for age, gender, and anthropometric data. In both groups the measurements were made by spirographic and plethysmographic techniques. In normal subjects functional residual capacity (FRC) and residual volume (RV) were measured during normal breathing and again during simulated sighing breathing to exclude technical artifacts resulting from hyperventilation during measurement by the helium closed circuit method. RESULTS: Patients with a sighing pattern of breathing had a normal total lung capacity (TLC) but significantly different partitioning of lung compartments compared with normal subjects. The vital capacity (VC) was lower when measured by both spirographic and plethysmographic methods and RV was higher. The forced expiratory volume in one second (FEV1) was also lower in patients with sighing breathing. The FEV1/VC and the maximal expiratory flow rates at 50% and at 25% of the forced vital capacity (V50 and V25) were normal and similar in both groups. In normal subjects there were no differences in RV when measured during quiet or simulated sighing breathing. CONCLUSIONS: Subjects with sighing breathing have a normal TLC with a higher RV and lower VC than normal subjects. There was no obvious physiological or anatomical explanation for this pattern.

Adult↗
PubMed1997

Risk factors for pulmonary barotrauma in divers.

STUDY OBJECTIVES: Pulmonary barotrauma (PBT) of ascent is a feared complication in compressed air diving. Although certain respiratory conditions are thought to increase the risk of suffering PBT and thus should preclude diving, in most cases of PBT, risk factors are described as not being present. The purpose of our study was to evaluate factors that possibly cause PBT. DESIGN: We analyzed 15 consecutive cases of PBT with respect to dive factors, clinical and radiologic features, and lung function. They were compared with 15 cases of decompression sickness without PBT, which appeared in the same period. RESULTS: Clinical features of PBT were arterial gas embolism (n=13), mediastinal emphysema (n=1), and pneumothorax (n=1). CT of the chest (performed in 12 cases) revealed subpleural emphysematous blebs in 5 cases that were not detected in preinjury and postinjury chest radiographs. A comparison of predive lung function between groups showed significantly lower midexpiratory flow rates at 50% and 25% of vital capacity in PBT patients (p<0.05 and p<0.02, respectively). CONCLUSIONS: These results indicate that divers with preexisting small lung cysts and/or end-expiratory flow limitation may be at risk of PBT.

Adult↗
PubMed2000

Tests of airway function in detecting and monitoring treatment of obliterative bronchiolitis after lung transplantation.

BACKGROUND: This study evaluated different tests of airway function in detection of obliterative bronchiolitis. It included analysis of spirogram within the time domain in patients with and without obliterative bronchiolitis (OB) after heart lung and lung transplantation. The purpose of this analysis is to evaluate which tests are of greatest value for early recognition of OB. METHODS: The coefficient of variation of different airway function tests was calculated in 13 patients who had no evidence of OB and 12 patients who developed OB post-transplantation. In the patients with OB the effect of treatment with total lymphoid irradiation (TLI) was investigated by comparing the rate of change of lung function before and after TLI. Several lung function tests were used. RESULTS: The measurements that showed the least variation were FEV(1), FVC, PEF, FEV(1)/FVC ratio and the Moment Ratio, while those which became abnormal earlier were FEV(1), FEV(1)/FVC, MEF(50), and the first moment. Additionally, the tests that became abnormal in a higher proportion of patients were MMEF, MEF(50), MEF(75), and the first moment. CONCLUSIONS: The results o thi support the use of simple spirometric indices for the detection of OB. In the patients with OB the rates of decline of lung function were significantly attenuated by treatment with TLI as determined by several different tests. KEYWORDS: obliterative bronchiolitis, lung transplantation, moments analysis, airway function tests, total lymphoid irradiation

Adolescent↗
PubMedDate not supplied

Occupational health problems among tobacco processing workers: a preliminary study.

Occupational health problems among 100 tobacco processing workers were investigated. Symptoms, including vomiting, giddiness, headache, etc. were found among 69 exposed subjects. It was also observed that the excretion rate of nicotine and cotinine increased among exposed subjects. Biochemical parameters were found to be within the normal range. Electrocardiographic findings were non-specific and clinically there was no evidence of hypertension or ischemic heart disease. Therefore, the symptoms in tobacco processing workers might possibly result from mild nicotine toxicity.

Adult↗
PubMedDate not supplied

Isocapnic hyperventilation with cold air in healthy non-smokers, smokers and asthmatic subjects.

Isocapnic hyperventilation with subfreezing air was performed by 15 healthy non-smokers, 10 asymptomatic smokers and 9 asthmatics. All subjects had normal ventilatory function and airway resistance (Raw) before challenge. The hyperventilation was performed twice. In one session, total respiratory resistance (Rrs) and reactance (Xrs) were measured at various frequencies, using a forced oscillation technique; in another session, vital capacity (VC), forced expiratory volume in 1 s (FEV1), maximal expiratory flow rates (FEF) and Raw were determined. In non-smokers, no changes in FEV1, FEF nor Raw were observed, whereas Rrs increased significantly (+ 20% of the prechallenge value), without change in resonant frequency nor in the Rrs-frequency relationship. This suggests a constrictory effect on central airways (possibly a narrowing of the glottis) only. In smokers, Rrs showed a similar, though longer lasting, increase than in non-smokers. Besides, a significant change of the Rrs-frequency relationship and a reduction in FEF at 50% of VC was found, suggesting an involvement of peripheral airways also. In asthmatics, bronchial reactivity was more pronounced, resulting in significant changes in all parameters: Rrs increased by about 100% of the prechallenge value, and became highly frequency dependent; Xrs decreased markedly, resulting in an increase in resonant frequency of the respiratory system. Similarly, VC, FEV1 and FEF decreased. These alterations are compatible with a more generalized constriction of the peripheral as well as central airways.

Airway Obstruction↗
PubMed1990

[Pulmonary function in the full-term newborn infant without respiratory problems].

Pulmonary function was measured by computerized pneumotacography in 13 term newborn infants without respiratory problems. Mean (+/- SD) for birth weight, gestation and postnatal age were 3149 +/- 366 g, 39.1 +/- 0.9 weeks, and 4.7 +/- 2.4 days. Esophageal balloon, differential transducer and nasal progs were used. The following parameters were measured in each respiration by the mean squears method: Dynamic compliance (Cdyn), total respiratory resistance (RRt) and work (WRt), respiratory time constant (KTt), rate (RR) and maximal inspiratory and respiratory flows (PIF, PEF). Reproductiveness was found to be good, as the differences between two determinations were not significant (p less than 0.05). The mean differences but for Cdyn (11.9%) were of less than 5%. The mean (+/- SD) and the 3 and 97 percentiles for each parameter studied were: RR 43.8 +/- 7.6 (32.6-61.2) rpm, Tv 6.6 +/- 0.7 (5.8-7.9) ml/kg, Vmin 285 +/- 55.6 (201-405) ml/min, Cdin/kg 1.64 +/- 0.31 (1.13-2.17) ml/cm/kg, RPt 65.2 +/- 21.6 (28.4 +/- 111.4) cm/L/seg, TRt 30.6 +/- 13.7 (15.3-58.8) g/cm/kg, PIF 2.9 +/- 0.6 (1.8 +/- 4.4) L/min y PEF 2.4 +/- 0.7 (1.2-4) L/min.

Humans↗
PubMed1993

Exposure to ozone alters regional function and particle dosimetry in the human lung.

Effects of experimental exposure to O3 (0.33 ppm) or filtered air on regional lung function were assessed in nine healthy male subjects. Immediately after 2-h chamber exposures, regional ventilation and particle dosimetry were measured by gamma camera imaging. The vertical distributions of a radiolabeled gas (133Xe) and aerosol (3.5-microns-diam insoluble 99mTc-tagged Fe2O3 particles) were quantitated for upper, middle, and lower lung regions; distribution data were corrected for regional differences in lung volume and tissue attenuation. Indexes of mechanical function, inspiratory capacity, and mid-maximal expiratory flow rates were significantly reduced after O3, but functional residual capacity remained unchanged. Exposure to O3 significantly enhanced the fraction of respired aerosol retained by the lung and altered the distribution pattern of deposited aerosol by increasing particle deposition to the middle lung region (P < 0.05). Aerosol penetration indexes, i.e., ratio of particle deposition in central lung regions to that in peripheral lung regions, and particle retention 24 h postinhalation (an index of aerosol deposition within alveoli and slowly clearing bronchioles) indicated that particle filtration efficiency had increased for tracheobronchial and parenchymal lung regions. For seven of the nine subjects, regional ventilation after O3 was reduced by 14% to the lung base and enhanced by 8 and 6% to the upper and middle lung regions, respectively; these changes were significant (P < 0.02) compared with ventilation after filtered air.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Successive effects of a vagolitic and a betadrenergic in the differential diagnosis of nonimmunologic and allergic asthma.

In order to determine whether the vagal mechanism is predominant in the physiopathology of asthma, we investigated in the first part of this work. If the new vagolithic, ipratropium can improved the respiratory parameters of asthmatic patients. If the effect is complete or admits yet the supplementary effect of a betadrenergic, Fenoterol. 46 asthmatic patients were registered in some spirographic parameters, e.g. FEV1 (Forced Expiratory Volume in 1 sec.), MMFR25-75 (Maximum Mid-expiratory Flow Rate between the 25 per cent and the 75 per cent of the forced vital capacity) and FEF 200-1200 (Forced Expiratory Flow between 200 ml. and 1200 ml. of the forced vital capacity). The same registers were made 30 minutes after aerolization with 0.05 mg of Ipratropium (two shots) and 10 minutes after 60 micrograms of Fenoterol (three shots). It was found that 78.5 per cent of the patients improved one of the parameters with Ipratropium more than 20 per cent. But 58 per cent of the patients showed an additional improvement with the betadrenergic in one or more of the parameters. This shows that in many cases the physiopathology of asthma is mixed, vagal and betareceptor dependent, in which the medication with Ipratropium plus Fenoterol will obtain better results. Only in some patients the bronchial spasm is vagolithic dependent exclusively, while few others responded to betadrenergic and only 9 per cent of patients did not respond to either one. In the second part of this work we tried to verify if by anamnestic inquiry and additional use of Ipratropium and Fenoterol it is possible to recognize one group of patients with asthma produced by nonimmunologic irritant factors acting on the large airways from another group with asthma due to inhalants allergens and spasm of the small bronchi. The same 46 patients were divided in two groups: Patients who recognize that asthmatic accesses begin after exercise, laughter cold weather, cigarette smoker exposure sprays, synthetics and insecticides. This is the predominantly irritative nonimmunologic group. Patients who recognize that coughing or wheezing begins after contact either with pollen, dust or danders. This is the predominantly allergic group. We proved that patients A improve more with Ipratropium and the opposite is true with patients B. The results with the two drugs are roughly parallel to the anamnestic records.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1995

Respiratory inductive plethysmography in the evaluation of lower airway obstruction during methacholine challenge in infants.

Respiratory inductive plethysmography (RIP) is a simple technique for an objective, noninvasive assessment of thoracoabdominal asynchrony, which in turn is an indirect measure of airway obstruction. We evaluated different indices of asynchrony obtained by RIP before and after methacholine-induced airway obstruction. Bronchial obstruction was elicited by progressive doubling concentrations of methacholine until a > 15% fall in the transcutaneous oxygen tension (PtcO2) had developed. Maximal expiratory flow rates at functional residual capacity (FRC) (VmaxFRC) was obtained by the squeeze technique before and after the challenge. Fifteen infants with a history of wheezing were studied after sedation. Thoracoabdominal movements were recorded with RIP bands placed around either the upper or the lower ribcage (RC) and around the abdomen (AB). An inspiratory asynchrony index (IAI) and an expiratory asynchrony index (EAI) were calculated as determined by the lag of RC relative to AB at start of inspiration and of expiration, respectively. The total time in asynchrony (TTA: the percentage of time in which the RC and the AB signals were in opposite direction) and phi (an angle derived from a Lissajous loop) were also calculated. All subjects responded to the challenge. The median fall in PtcO2 following methacholine challenge was 23.6% and in VmaxFRC was 43%. A large scatter of baseline values was found for all indices with the exception of TTA. There was no correlation between TTA and age, length, or VmaxFRC. The IAI and EAI with the RC band in the upper position were the most sensitive indices, both within subjects (65% of the subjects had a significant change in IAI and 80% in EAI) and for the group as a whole (median values increased for IAI, P = 0.007, and for EAI, P = 0.017). TTA and phi were less sensitive, and a great discrepancy was observed between the two measurements. Poor results were obtained with the RC band in the lower position. No correlations were found between the changes in IAI and EAI, with the RC band around the lower chest and VmaxFRC. We conclude that IAI and EAI, measured with the RC band in the upper position and another band around the abdomen, can detect changes in thoracoabdominal asynchrony in most infants. The usefulness of assessing IAI and EAI in infants with acute lower airway obstruction needs to be determined.

Abdomen↗
PubMed1981

Standardization of work intensity for evaluation of exercise-induced bronchoconstriction.

Reactivity of airways to 6 min of graded intensity treadmill work was studied in nine asthmatic and 15 non-asthmatic subjects. After performing a progressive VO2 max treadmill test, each subject completed five 6-min exercise tests at selected intensities: 40, 60, 80, and 100% VO2 max; and at 80% of VO2 max predicted from heartrate. Pulmonary function measures recorded after exercise demonstrated a direct relationship between work intensity and exercise induced bronchoconstriction (EIB) for both groups, with the asthmatics showing their lowest values at 80% VO2 max. Heartrate-set work intensities produced a wide range of aerobic demand, thus significantly increasing the variability of the EIB response recorded.

Adult↗
PubMedDate not supplied

Pathologic lung function in children and adolescents with congenital heart defects.

Lung function tests (i.e., spirometry, flow volume, and body plethysmography) were performed in 213 patients (age 6-21 years, mean 11.3 years) with hemodynamically significant congenital heart defects: atrial septal defect, ventricular septal defect (VSD), tetralogy of Fallot, aortic stenosis and coarctation of the aorta. We measured lung vital capacity, total lung capacity (TLC), residual volume (RV), the percentage ratio of the latter two measurements (%RV/TLC), maximal expiratory flow rates at 25% and 50% of vital capacity, and specific airway conductance. Pulmonary restriction dominated in patients with tetralogy of Fallot; pulmonary hyperinflation was more frequent in patients with VSD and coarctation of the aorta; and obstruction of the airways was observed most frequently in patients with tetralogy of Fallot. In conclusion, we found a range of pathologic lung function parameters in patients with hemodynamically significant congenital heart defects.

Adolescent↗
PubMed1982

Mouth spraying versus inhalation of fenoterol aerosol in healthy subjects and asthmatic patients.

Four hundred micrograms of fenoterol aerosol were administered to 10 healthy subjects and nine asthmatic patients. Fenoterol was either inhaled or sprayed into the mouth carefully avoiding inhalation. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1.0), maximal expiratory flow rates (MEFR), specific airways conductance (sGaw), total lung capacity (TLC), residual volume (RV), and heart rate (HR) were measured before and up to one hour after fenoterol administration. FVC, FEV1.0, MEFR and sGaw increased significantly after inhalation of fenoterol in both asthmatic patients and healthy subjects. The increase was significantly greater in the asthmatic group. After buccal administration of fenoterol FVC, FEV1.0 and sGaw increased significantly in both asthmatic patients and healthy subjects, and there was no significant difference between the two groups. Increased heart rate and side effects were observed only in healthy subjects and only after inhalation. Buccal administration of fenoterol to both asthmatic patients and healthy subjects induced a clearcut bronchodilation (though less than that produced by inhalation), probably by absorption of the drug through the oral mucosa.

Adolescent↗
PubMed1989

Pulmonary effects of sulfur dioxide exposure and ipratropium bromide pretreatment in adults with nonallergic asthma.

In this study we examined the potential short-term effect of sulfur dioxide (SO2) on total respiratory resistance and forced expiratory volume in patients with nonallergic asthma. A group of nine adult subjects with nonallergic asthma, 55 years of age or older, were exposed to SO2 at 0, 0.5, and 1.0 ppm for 20 minutes at rest followed by 10 minutes during light-moderate exercise. The measures of pulmonary function assessed were FEV1, specific total respiratory resistance (SRT), and maximal expiratory flow rates at 50% (Vmax50) and 75% (Vmax75) of expired vital capacity. Measurements were made before exposure to SO2 (baseline), postresting exposure, postexercising exposure, and at 30 minutes thereafter (recovery). Repeat measure analysis of variance revealed a statistically significant dose-response effect of SO2 inhalation on FEV1 (p = 0.008), SRT (p = 0.033), Vmax50 (p = 0.017), and Vmax75 (p = 0.048). Eight subjects had repeat exposure to SO2 at 1.0 ppm after treatment with either placebo or ipratropium bromide, 60 micrograms by metered-dose inhaler. Inpratropium bromide treatment, compared to placebo treatment, resulted in a statistically significant improvement in all baseline measures of pulmonary function: FEV1 (p = 0.017), SRT (p = 0.027), Vmax50 (p = 0.018), and Vmax75 (p = 0.035). However, this drug did not significantly alter the proportionate change in pulmonary function caused by SO2 inhalation in these subjects. These findings indicate that adults with nonallergic asthma are sensitive to short-term low-level SO2 exposure and that treatment with 60 micrograms of ipratropium bromide causes significant bronchodilation but does not protect, completely, these patients from the effect of SO2 inhalation.

Aged↗
PubMed1993

A double-blind, placebo controlled trial of solidified benzyl benzoate applied in dwellings of asthmatic patients sensitive to mites: clinical efficacy and effect on mite allergens.

BACKGROUND: The aim of this double-blind, randomized study was to investigate the effectiveness of an acaricidal cleaning product in modifying both clinical symptoms and mite allergen levels over a period of at least 1 year. METHODS: Twenty-six asthmatic patients with proven Dermatophagoides pteronyssinus (Dp) asthma were selected; three were withdrawn from the trial. The patients' homes were divided into two groups; 11 homes were treated with solidified benzyl benzoate and tenside agents (A), and 12 were treated with a placebo (P). Two applications were performed at the beginning of the trial and at least 6 months later. Patients were examined 1 month before the trial, at the beginning of the trial, and every 3 months over a period of 1 year. Indoor mite exposure was evaluated by three methods: semiquantitative guanine determinations, quantitative guanine determinations, and the measurement of Der p I + Der f 1 (antigen P, of Dp + antigen F1 of D. farinae) levels. RESULTS: The symptom scores established at the beginning of the trial and 12 months later showed a statistically significant improvement only in the A group (p < 0.01). The visual analog scale also showed a statistically significant difference both in the A (p < 0.05) and P groups (p < 0.01). No statistical differences were found between medication scores in the A or P groups. A statistically significant increase was also observed for forced expiratory volume in 1 second and maximal expiratory flow rate 25/75 in the two groups (p < 0.05 for P group; p < 0.01 for A group). The mean decreases in Der p I + Der f 1 in patient mattresses between the beginning of the trial and after 12 months were 20% for the acaricide group and 17% for the placebo group, respectively (NS). For house dust samples with origins other than the patients' mattresses we found significant decreases in Der p I+Der f 1 in the A group (p < 0.01 for carpets and p < 0.05 for upholstery elements).

Adolescent↗
PubMed1995

Increase of lung transfer factor in early sarcoidosis.

Dynamic spirometry and the lung transfer factor for CO (TLCO) were determined in 41 non-smoking patients with sarcoidosis before and after steroid treatment. Dynamic spirometry revealed usual stage-dependent restrictive and/or obstructive abnormalities; only maximal expiratory flow rate at 75% FVC (MEF75) was significantly increased after steroid treatment in stage 2 patients. The new finding is that TLCO was increased in stage 1 [on average 21% above the predicted values (p.v.)], but it was decreased in stage 2 (11% below p.v.) and stage 3 (27% below p.v.). The increase in TLCO in stage 1 was predominantly caused by an increase in TLCO membrane component (Dm) (33% above p.v.), while the pulmonary capillary blood volume (Vc') increased less (19% above p.v.). Steroid treatment significantly reduced TLCO, Dm and Vc' in stage 1 (for 14, 17 and 18% of the respective baseline values), whereas it caused TLCO and Dm increases in stage 2 (for 8 and 10% of the respective baseline values). In conclusion, a TLCO in pulmonary sarcoidosis may not only be decreased in its advanced stages, but also exhibit increased values, which appeared related to the subclinical inflammatory reaction in the stage 1 patients.

Adult↗
PubMed2006

Does gender affect pulmonary function and exercise capacity?

It is well established that women exhibit several anatomic and physiologic characteristics that distinguish their responses to exercise from those of men. These factors have been shown to influence the training response and contribute to lower maximal aerobic power in women. Additionally, the reproductive hormones, estrogen and progesterone, can influence ventilation, substrate metabolism, thermoregulation, and pulmonary function during exercise. Pulmonary structural and morphologic differences between genders include smaller vital capacity and maximal expiratory flow rates, reduced airway diameter, and a smaller diffusion surface than age- and height-matched men. These differences may have an effect on the integrated ventilatory response, respiratory muscle work, and in pulmonary gas exchange during exercise. Specifically, recent evidence suggests that during heavy exercise, women demonstrate greater expiratory flow limitation, an increased work of breathing, and perhaps greater exercise induced arterial hypoxemia compared to men. The consequence of these pulmonary effects has the potential to adversely affect aerobic capacity and exercise tolerance in women.

Aging↗