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PubMed1986

Lung function and respiratory muscle strength after propranolol in thyrotoxicosis.

Thirty-five thyrotoxic patients were assessed before treatment, after treatment with propranolol, and after antithyroid drugs. The first group of patients (n = 17) performed the following tests at all three assessment points: forced expiratory volume in the first second (FEV1), vital capacity (VC), functional residual capacity (FRC), residual volume (RV), total lung capacity (TLC), maximal mid-expiratory flow rate (MMFR), diffusing capacity for carbon monoxide (DLCO), and maximum static inspiratory and expiratory mouth pressures (PImax and PEmax). Arterial blood gas analysis was also performed for the first group of patients. No significant changes were seen either after propranolol or after antithyroid drugs in the FRC, RV, TLC, MMFR, DLCO, or blood gases. The remaining 18 patients, group 2, performed only the FEV1, VC, PImax, and PEmax tests at each assessment. The only index of respiratory function that improved significantly after propranolol was PImax (from 46.5 +/- 16.5 to 53.2 +/- 22 cmH2O, p less than 0.01). This suggests that adrenergic excess may play a role in thyrotoxic inspiratory muscle weakness. After antithyroid drugs, PImax, PEmax, FEV1, and VC all increased significantly as expected.

Adolescent↗
PubMed2000

Adult-type pulmonary function tests in infants without respiratory disease.

A new method that permits the measurement of adult-type maximal expiratory flow-volume curves and fractional lung volumes in sedated infants was recently described. The purpose of this study was to define the normal range for these new measures of pulmonary function in infants and young children. Measurements of forced expiratory flows and fractional lung volume were made on 35 occasions in 22 children (ages 3-120 weeks) without respiratory disease. Maximal expiratory flow-volume curves were measured by the raised lung volume, thoracoabdominal compression technique. Functional residual capacity (FRC) was measured plethysmographically. Measurements of total lung capacity (TLC), residual volume (RV), FRC, forced vital capacity (FVC), and forced expiratory flows at 25, 50, 75, 85, and between 25% and 75% of expired FVC (FEF(25), FEF(50), FEF(75), FEF(85), and FEF(25-75), respectively) all increased in relation to infant length (P<0.001). RV/TLC, FRC/TLC, and FEF(25-75)/FVC declined in relation to increasing length (P<0.001). The forced expiratory flow and fractional lung volume measurements using this method were similar to previously reported estimates using other methods. These estimates represent a reasonable reference standard for infants and young children with respiratory problems.

Anesthesia, General↗
PubMed2005

Bronchial mucosal mast cells in asymptomatic smokers relation to structure, lung function and emphysema.

The pathologic mechanisms of chronic obstructive pulmonary disease (COPD) most certainly involves neutrophil granulocytes, cytotoxic T-cells, macophages and mast cells. The aim of this study was to investigate the relation between the number of mast cells in different compartments in bronchial biopsies of central proximal airways to structural changes, lung function tests and emphysema detected by high resolution computed tomography (HRCT). Twenty nine asymptomatic smoking and 16 never-smoking men from a population study were recruited. Central bronchial biopsies were stained to identify mast cells by immunohistochemistry. The number of mast cells in the epithelium, lamina propria and smooth muscle as well as epithelial integrity and thickness of the tenascin and laminin layer were determined. Smokers had increased numbers of mast cells in all compartments (P<0.001). Structural changes were correlated to mast cell numbers with the closest associations to mast cell numbers in the smooth muscle [epithelial integrity (R(S)=-0.48, P=0.008), laminin layer (R(S)=0.63, P=0.0002), tenascin layer (R(S)=0.40, P=0.03)]. Similar correlations between mast cells and lung function tests were seen [functional residual capacity (FRC) (R(S)=0.60, P=0.0006), total lung capacity (TLC) (R(S)=0.44, P=0.02) and residual volume (RV) (R(S)=0.41, P=0.03)]. No correlations could be detected between mast cells and FEV1 or to emphysema. Smoking is associated with an increase of mast cells in all compartments of the bronchial mucosa, including smooth muscle, and this is related to altered airway structure and function.

Aged↗
PubMedDate not supplied

Pulmonary function and high-resolution CT findings five years after disease onset in patients with Wegener's granulomatosis.

OBJECTIVE: Although pulmonary involvement is common in Wegener's granulomatosis (WG), little is known about the pulmonary outcome. We evaluated the relationship between clinical disease characteristics and pulmonary function and high-resolution computed tomography (HRCT) findings after disease duration of 5 years. METHODS: A pulmonary function test (PFT) and pulmonary HRCT were performed in 41 patients from a population-based register of WG. Clinical predictors for abnormal PFT and HRCT were tested by logistic regression. RESULTS: Previous WG-related lung involvement (PLI) had occurred in 80% of patients, but only 24% of patients still reported pulmonary symptoms at the research visit. One-third of patients had abnormal PFT findings, with reduced alveolar diffusion by KCO (transfer coefficient) being most common (24%). The number of PLI episodes was associated with reduced KCO and reduced FEV1% (forced expiratory volume in 1 s as a percentage of forced vital capacity) (overall presence 10%). Reduced KCO was also associated with disease duration. Reduced total lung capacity (TLC) (overall presence 8%) was only related to prior WG-related lung nodules. Pulmonary HRCT was abnormal in 80%, but with more severe abnormalities in only 30%. Pleural thickening and parenchymal bands were associated with PLI. None of the treatment variables was associated with the PFT or HRCT findings. CONCLUSION: Five years after disease onset a quarter of the WG patients reported pulmonary symptoms, had severe abnormalities on HRCT, and abnormal PFT. The correlation between these abnormalities was poor, but the number of pulmonary involvements was a risk factor for reduced gas diffusion, obstructive lung disease, parenchymal bands, and pleural thickening. Treatment variables had no discernible negative pulmonary effects.

Adolescent↗
PubMed1987

The value of 99mTc macroaggregated albumin lung perfusion scanning in the prediction of postpneumonectomy function and pulmonary artery pressure.

99mTc macroaggregated albumin lung perfusion scans were performed with assessment of pulmonary hemodynamics in 14 male patients with a centrally located lung tumor, subjected to pneumonectomy. In 7 patients perfusion of the affected lung was less than one third of total perfusion. However, all tumors were resectable. Results show that predictive value of the perfusion scan was significant (p less than 0.02) with regard to forced expiratory volume in the first second (FEV1, r = 0.80). A fair but not significant correlation existed in the prediction of vital capacity (VC, r = 0.64) and total lung capacity (TLC, r = 0.71). No correlation was found between perioperative change in mean pulmonary artery pressure (MPAP) and either relative radionuclide uptake of the affected lung or predicted FEV1. So, the lung perfusion scan cannot be used in preoperative estimation of postoperative MPAP.

Aged↗
PubMed1984

Prospective evaluation of amiodarone pulmonary toxicity.

Reports of pulmonary infiltrates in patients taking amiodarone, initiated the study of 69 patients for pulmonary toxicity using serial chest roentgenograms (CXRs), pulmonary function tests (PFTs), and symptoms before and during therapy. Mean PFTs did not significantly change from their baseline normal values, but 10 percent of patients had a greater than or equal to 15 percent fall in total lung capacity, and 28 percent a greater than or equal to 15 percent fall in diffusion capacity (DCO) following treatment. Initial abnormalities in pulmonary function or CXR were predictive of risk of developing pulmonary toxicity. Degree of exposure to amiodarone (dose plus duration) correlated only weakly with development of pulmonary toxicity, which could occur in patients taking relatively small doses of the drug. Pulmonary complications of amiodarone are common, in most cases reversible, and often confused with congestive heart failure or pneumonia. Patients should be evaluated before treatment by assessing symptoms, CXRs, and DCO. Patients with initial abnormalities in these parameters, particularly both CXR and DCO abnormalities, should be considered for alternative therapy.

Adult↗
PubMed1989

Nitrogen dead space in heavy smokers aged 44-58 years.

Functional and alveolar dead spaces for nitrogen (VDF and VDalv) were calculated in a population of 20 male and 20 female heavy smokers and compared to data from static and forced spirometry (functional residual capacity [FRC], residual volume [RV], lung clearance index [LCI] and volume of trapped gas [VTG]) obtained with the same multiple-breath nitrogen wash-out as the dead spaces, and to variables considered sensitive to small airways disease measured with a single-breath nitrogen elimination (closing volume in per cent of vital capacity [CV%], closing capacity in per cent of total lung capacity [CC%] and slope index [SI]). Both nitrogen dead spaces increased with tidal volume in smokers as well as in healthy non-smokers. The majority of smokers were outside the predicted mean +2 SD for VTG (75%), CC and VDalv (70%) and SI (65%). The following variables were less sensitive for disclosing abnormality: CV (55%), RV (53%), LCI (38%) and forced expired volume in the first second (FEV1, 33%). If high sensitivity is considered preferable in epidemiological studies, the nitrogen dead spaces are equally as sensitive as the better of earlier described tests, and significantly superior to LCI and FEV1. Being tests that measure alveolar distribution of inhaled gas, they are probably sensitive to small airways disease.

Adult↗
PubMed1985

Effects of deep inhalation in asthma: relative airway and parenchymal hysteresis.

Asthmatic subjects were screened for the effects or volume history on the degree of induced airway obstruction with methacholine by comparing isovolumic maximal expiratory flows (Vmax) from partial expiratory flow-volume curves (P) begun near functional residual capacity (FRC) followed by maximal expiratory flow-volume (M) maneuvers begun from total lung capacity (TLC). The isovolumic Vmax values from M and P maneuvers defined two groups: one had a high M/P ratio (high group), indicating a large degree of reversal with deep inhalation, another had a low M/P ratio (low group), indicating minimal reversal. No differences were found between groups. A more complete study was later performed in which we measured specific airway conductance (sGaw) and anatomical dead space (VD) as indices of airway size and hysteresis before and after deep inhalation. The area of quasi-static transpulmonary pressure (Ptp) volume (V) curves from FRC to TLC and back to FRC was measured as an index of parenchymal hysteresis. At base line both groups showed a decrease in both sGaw and VD after a deep inhalation (DI). After constriction neither group changed VD after DI, whereas sGaw increased significantly in the high group after DI. This suggests that dilation of airways with DI occurred peripheral to those contributing to VD in the high group. The areas of the Ptp-V curves were equal at base line; yet the increase in areas with constriction in the low group was much greater.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Anthropometry and lung function of 10- to 12-year-old Bolivian boys.

Anthropometric measurements of 23 HAHSES, 44 HALSES, 43 LAHSES, and 28 LALSES boys (see Introduction to this Supplement) are presented here. They include body height (H), body weight (BW), upper arm circumference (UAC), and skinfold thickness taken at four locations. From these measurements, body fat, lean body mass, and body mass index (BMI = BW/H2) were calculated. The degree of maturation was assessed according to Tanner, orchidometry, and by quantification of testosterone in saliva. Lung function data include: vital capacity (VC), forced expired volume per 1 s (FEV1), functional residual capacity (FRC), residual volume (RV), and total lung capacity (TLC). The results show enhanced lung volumes in both HA groups in comparison to LA groups, with HALSES boys having the greatest increase, even though the LSES boys were significantly smaller compared to the HSES boys at both altitudes and their growth was delayed by approximately 2 years. From the anthropometric data it appears that physical growth of prepubertal boys is dependent on SES but not on high-altitude exposure. We tentatively conclude that chronic hypoxia per se does not affect physical growth in prepubertal boys in an Andean environment and that development of lung function is accelerated in relation to linear growth as has been suggested by other authors (15).

Altitude↗
PubMed2001

In defence of the carbon monoxide transfer coefficient Kco (TL/VA).

The carbon monoxide transfer factor (TL,co) is the product of the two primary measurements during breath-holding, the CO transfer coefficient (Kco) and the alveolar volume (VA). Kco is essentially the rate constant for alveolar CO uptake (Krogh's kco), and in healthy subjects, increases when VA is reduced by submaximal inflation, or when pulmonary blood flow increases. Recently, new reference values were proposed for clinical use which included the observed VA at full inflation; this was claimed to "eliminate the need for Kco". In this commentary, some mechanisms e.g. respiratory muscle weakness, lung resection, diffuse alveolar damage and airflow obstruction, which decrease or increase total lung capacity (TLC) are reviewed. Even when alveolar structure and function are normal, the change in Kco at a given VA varies according to the underlying pathophysiological mechanism. The advantages and disadvantages of normalizing Kco and TL,co to predisease predicted TLC or to the patient's actual VA (using lack of expansion or loss of alveolar units models) are considered. Examination of carbon monoxide transfer coefficient and alveolar volume separately provides information on disease pathophysiology which cannot be obtained from their product, the carbon monoxide transfer factor.

Airway Resistance↗
PubMed1975

[Segmentary topography and ventilation gradients in human lungs].

Segmentary topography of the air volume was studied by regional electroplethysmography of the lungs. A distinct apical-basal gradient was shown to be present in men tested in supine position, along with the dorsal-ventral gradient; the origin of the apical-basal gradient could not be explained from the point of view of the gravitational mechanism. A possibility of recalculation of the electroplethysmographic index of the percentage of the air content in the lobe of the lung to the regional air volume index in the lungs, and the principal possibility of calculation of the regional total lung capacity index with the help of electroplethysmography was shown.

Adult↗
PubMedDate not supplied

[Radiographic measurement of the total pulmonary capacity: comparison of 2 planimetric methods].

We analyzed accuracy and reproducibility of a radiographic method for calculation of total lung capacity (TLC) from the sum of pulmonary area. Pulmonary area from a routine postero-anterior and lateral chest radiography was measured by two methods: using a planimeter (standard) and with a virgin radiographic plaque with lines separating squares of 1cm per side. Plethismographic TLC was obtained adding the functional residual capacity to inspiratory capacity. We studied 13 healthy subjects (mean age of 30 years, eight males), 13 with interstitial lung disease (mean age of 45 years, two males) and 12 with chronic bronchitis or emphysema (mean age of 63 years, three males). Measured TLC varied from 1.9 to 7.2 liters. The linear regression equation found was: TLC = 0.007 total lung area (cm2) 0.572, R = 0.906, P less than 0.001 which is very similar to that reported by Harris et al.8 Interobserver variability in the measurement was very small taking into account that no efforts were made to uniformize the observers. Main interobserver differences were in the tracing of the lung limits, and not in the actual measurement of the lung area. We found no differences between the two methods for measuring lung area except that the planimeter is faster and more reproducible. Radiographic method for measuring TLC is accurate and available in most places.

Adult↗
PubMed1998

A prospective algorithm for the management of air leaks after pulmonary resection.

BACKGROUND: Air leaks (ALs) are a common complication after pulmonary resection, yet there is no consensus on their management. METHODS: An algorithm for the management of chest tubes (CT) and ALs was applied prospectively to 101 consecutive patients who underwent elective pulmonary resection. Air leaks were graded daily as forced expiratory only, expiratory only, inspiratory only, or continuous. All CTs were kept on 20 cm of suction until postoperative day 2 and were then converted to water seal. On postoperative day 3, if both a pneumothorax and AL were present, the CT was placed to 10 cm H2O of suction. If a pneumothorax was present without an AL, the CT was returned to 20 cm H2O of suction. Air leaks that persisted after postoperative day 7 were treated with talc slurry. RESULTS: There were 101 patients (67 men); on postoperative day 1, 26 had ALs and all were expiratory only. Univariable analysis showed a low ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) (p = 0.005), increased age (p = 0.007), increased ratio of residual volume to total lung capacity (RV/TLC) (p = 0.04), increased RV (p = 0.02), and an increased functional residual capacity (FRC) (p = 0.02) to predict the presence of an AL on postoperative day 1. By postoperative day 2, 22 patients had expiratory ALs. After 12 hours of water seal, 13 of the 22 patients' ALs had stopped, and 3 more sealed by the morning of postoperative day 3. However, 2 of the 6 patients whose ALs continued experienced a pneumothorax. Five of the 6 patients with ALs on postoperative day 4 still had ALs on postoperative day 7, and all were treated by talc slurry through the CT. All ALs resolved within 24 hours after talc slurry. CONCLUSIONS: Most ALs after pulmonary resection are expiratory only. A low FEV1/FVC ratio, increased age, increased RV/TLC ratio, increased RV, and an increased FRC were predictors of having an ALs on postoperative day 1. Conversion from suction to water seal is an effective way of sealing expiratory AL, and pneumothorax is rare. If an expiratory AL does not stop by postoperative day 4 it will probably persist until postoperative day 7, and talc slurry may be an effective treatment.

Adult↗
PubMed1998

Re-breathing vs single-breath TLCO in patients with unequal ventilation and diffusion.

The single-breath (SB) method for determining the transfer factor for carbon monoxide (TLCO) is of limited value for the detection of diffusion disorders on the alveolar level, because the results are influenced by unequal distribution of ventilation and diffusion. The rebreathing method (RB) is thought not to be influenced by these inequalities. To the authors' knowledge, no study has measured both TLCORB and TLCOSB systematically and compared them with regard to the influence of unequal ventilation and diffusion. Therefore, the present study measured total lung capacity (TLC) as well as TLCO, both with the RB vital capacity method and the SB method, using the same apparatus in 10 healthy subjects and in 35 patients with chronic obstructive pulmonary disease (COPD). These patients are known to have increased unequal ventilation and diffusion in comparison with healthy subjects. In the healthy subjects, a small difference was found between TLC measured with the RB method (TLCRB) divided by the predicted value (TLCRB/pred) and TLCSB/pred (mean difference 0.07; SE = 0.02); no significant difference was found between TLCORB divided by the predicted value of TLCOSB (TLCORB/pred) and TLCOSB/pred. In the COPD patients, however, TLCRB/pred was larger than TLCSB/pred (mean difference 0.17; SE = 0.02) and TLCORB/pred was larger than TLCOSB/pred (mean difference 0.23; SE = 0.05). Multiple regression analysis revealed that in the COPD patients, 54% of the variance of the difference between TLCRB/pred and TLCSB/pred, and 76% of the variance of the difference between TLCORB/pred and TLCOSB/pred, were explained by parameters related to unequal ventilation and diffusion. In 25 of the 35 COPD patients, TLCOSB/pred was less than 0.8, whereas in 11 of these 25 patients, TLCORB/pred was more than 0.8. This difference was significant (P = 0.0005). In these 11 patients, the SB measurement resulted in the incorrect diagnosis of a diffusion disorder on the alveolar level. The RB method, however, never resulted in the diagnosis of a diffusion disorder when TLCOSB/pred was larger than 0.8. It is concluded that in a significant number of COPD patients, TLCOSB is below the normal range, whereas TLCORB is not below the normal range. This difference between TLCORB and TLCOSB is related to the combined effect of unequal ventilation and diffusion, and is of clinical importance for the detection of a diffusion disorder on the alveolar level.

Adult↗
PubMed1977

Pulmonary function in former alcoholics.

Pulmonary function was evaluated in 44 former alcoholics (abstinence, 0.5 to 32 years) without cardiac or specific pulmonary disease. All were members of Alcoholics Anonymous. Fourteen subjects (32 percent) were non-smokers, ex-smokers, and cigar or pipe smokers, yet 28 subjects (64 percent) had abnormal expiratory flow rates, and 17 (39 percent) had an elevated value for the ratio of the residual volume to the total lung capacity. Single-breath diffusing capacity was abnormal in seven subjects (16 percent). Of interest was the high incidence (77 percent) of obstructive phenomena among the women. This high incidence of abnormalities among both the men and women could not be attributed to previous pulmonary infection or smoking. Comparison of these patients with chronic alcoholics suggests that the obstructive component in these patients is, in part, a result of their past alcoholic intake and that it is not reversed by abstinence. On the other hand, the impairment in diffusion, which was so common in alcoholics, appears to be reversible with sobriety.

Adult↗
PubMed2006

Incidence of pulmonary hypertension and its clinical relevance in patients with sarcoidosis.

OBJECTIVE: To investigate the frequency of pulmonary hypertension (PH) and clinical parameters associated with PH in sarcoidosis patients. METHODS: A prospective, observational study was performed on 246 consecutive Japanese sarcoidosis patients followed up at the outpatient sarcoidosis clinic in the Central Clinic of Kyoto. The patients were evaluated for PH by Doppler echocardiography. Among these patients, 192 underwent pulmonary function tests. In addition, high-resolution CT of the lung was evaluated for the presence of lymph node enlargement, lung opacity, and thickening of bronchovascular bundles in 122 patients. PH was defined as estimated systolic pulmonary artery pressure (sPAP) > or = 40 mm Hg. The frequency of PH was evaluated, and clinical parameters were compared between patients with PH and those without PH. RESULTS: Among 212 patients who were successfully evaluated for sPAP, 12 patients (5.7%) had PH. Patients with PH had the following clinical characteristics: advanced chest radiographic stage, decreased oxygen saturation, predominantly male gender, and decreased percentage of predicted vital capacity, percentage of predicted FVC, percentage of predicted FEV1, percentage of predicted functional residual capacity, and percentage of predicted total lung capacity (%TLC). Multivariate logistic regression analysis showed that decreased %TLC was independently associated with PH. There was a weak negative correlation between sPAP and %TLC (p < 0.05). CONCLUSIONS: The frequency of PH in Japanese sarcoidosis patients was 5.7% evaluated with Doppler echocardiography. Decreased lung volume increases the risk of PH developing in patients with sarcoidosis.

Echocardiography, Doppler↗
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↗
PubMed1988

The lung volume at which shunting occurs with inhalation anesthesia.

The relationship between functional residual capacity (FRC) and shunt development with halothane anesthesia in 18 nonobese surgical patients (age, 21-34 yr) was studied. FRC was measured by helium dilution, and intrapulmonary shunt was distinguished from ventilation-perfusion inequality by multiple tracer inert gas elimination analysis. Awake supine FRC was 34.6 +/- 6.6% (mean +/- SD) of total lung capacity (TLC), and closing capacity (CC) was 29.8 +/- 5.3% of TLC. Anesthesia, muscle paralysis, tracheal intubation, and mechanical ventilation produced an average 14.6 +/- 13.3% FRC reduction to an average anesthesia FRC 29.8% of TLC (P = 0.002). Shunt increased from 1.2% +/- 1.5% awake to 8.6 +/- 8.3% during anesthesia (P = 0.005). A nonlinear relationship was found between shunt and FRC/TLC so that anesthetized subjects with an FRC less than awake CC had an average 11.4 +/- 8.3% shunt, whereas subjects with an FRC greater than CC had a 2.4 +/- 2.8% shunt (P = 0.025). Nonsmokers developed shunt only if FRC was less than CC. Smokers showed a significantly higher shunt for a given (FRC-CC)/TLC compared to nonsmokers (P less than 0.001). The slope of the regression of shunt on BMI (body mass index = weight/height2) showed a significant increase during anesthesia (P = 0.005), and smokers had a significantly higher slope compared to nonsmokers (P = 0.001). These findings suggest a gravity-dependent mechanism for intrapulmonary shunting during anesthesia. Therefore, shunting was due to dependent regional lung volume reduction associated with an FRC decrease to less than closing capacity. The enhanced intrapulmonary shunting in smokers may have been related to the increased dependent regional residual volume associated with smoking.

Adult↗