Validity, variability and reproducibility of single-breath total lung capacity determinations in normal subjects.
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Adult↗
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Results for “Total Lung Capacity”
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[Changes in total lung capacity in patients with circulatory insufficiency].
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Aminophylline↗
[Roentgenographic and bodyplethysmographic determination of total lung capacity in normal persons and patients with obstructive and restrictive lung function disturbances (author's transl)].
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Humans↗
Respiratory function 8 years after a diagnosis of peripheral airways disease.
A program of screening for airways obstruction was designed to examine: (1) the precision and the reliability of the proposed tests (2) the evolution of respiratory impairment in 69 subjects, 8 years after a diagnosis of peripheral (small) airways obstruction. The tests that exhibit very good reliability are: vital capacity, total lung capacity, 1-second forced expiratory volume, single breath CO diffusion capacity, curvilinearity score; and the ratio of closing capacity to total lung capacity. 39% of smokers and 15% of nonsmokers developed central airways obstruction 8 years after the diagnosis of peripheral airways disease. These results confirm the hypothesis that small airways may be regarded as a noisy rather than a silent zone.
Airway Obstruction↗
Transmission of sound generated by sternal percussion.
We indirectly determined the transmission path of sound generated by sternal percussion in five healthy subjects. We percussed the sternum of each subject while recording the output audio signal at the posterior left and right upper and lower lung zones. Sound measurements were done during apnea at functional residual capacity, total lung capacity, and residual volume both with the lungs filled with air and with an 80% He-20% O2 (heliox) gas mixture. Three acoustic indexes were calculated from the output sound pulse: the peak-to-peak amplitude, the peak frequency, and the mid-power frequency. We found that the average values of all indexes tended to be greater in the upper than in the ipsilateral lower lung zones. In the upper zones, peak-to-peak amplitude was greater at total lung capacity and residual volume than at functional residual capacity. Replacing air with heliox did not change these results. These experiments, together with others performed during Mueller and Valsalva maneuvers, suggest that resonance of the chest cage is the predominant factor determining the transmission of sternal percussion sounds to the posterior chest wall. The transmission seems to be only minimally affected by the acoustic characteristics of the lung parenchyma.
Adult↗
Estimation of regional gas and tissue volumes of the lung in supine man using computed tomography.
This study was intended to discover how well computed tomography could recover the volume and weight of lung like foams in a body like shell, and then how well it could recover the volume and weight of the lungs in supine man. Model thoraces were made with various loaves of bread submerged in water. Computed tomography scans recovered the volume of the model lungs (true volume range 250-12,500 ml) within +0.2 (SD 68) ml and their weights (true range 72-3125 g) within +30 (78) g. Scans also recovered successive injections of 50 ml of water, within +/- 5 ml. Scans in 12 healthy supine men recovered their vital capacities, total lung capacities (TLC), and predicted tissue volumes with comparable accuracy. At total lung capacity the mean tissue volume of single lungs was 431 (64) ml and at residual volume (RV) it was 427 (63) ml. Tissue volume was then used to match inspiratory and expiratory slices and calculate regional ventilation. Throughout the mid 90% of lung the RV/TLC ratio was fairly constant--mean 21% (5%). New methods of presenting such regional data graphically and automatically are also described.
Adult↗
[Assessment of lung function in asthmatic children during a stay on the North Sea coast (author's transl)].
In a group of 40 asthmatic children, the following lung function parameters were measured during symptom free period: functional residual capacity (FRC); vital capacity (VC); total lung capacity (TLC); total pulmonary flow resistance (R1) and dynamic lung compliance (C1dyn). All the children were examined during their stay on Norderney (an island in the North Sea). The mean values of all measured lung volumes were significantly larger than the predicted values (p < 0.001), the mean value of R1 corresponded to the predicted one whereas the mean value of C1dyn was significantly smaller (p < 0.001), most of the individual values being within the normal range. After inhalation of Orciprenaline the mean value of R1 was significantly smaller than the initial value (about 15%; p < 0.001), whereas the lung volumes as well as C1 dyn were still unchanged. The influence of Orciprenaline on R1 and was only temporary and was reproducible 24 h later. Ther low mean value of C1 cyn was independent of the length of stay on Norderney. The reasons for this phenomena are discussed: obstructions and/or occlusions in the smallest airways seem to be the most important factor, uninfluenced by beta-2-mimetic drugs.
Adolescent↗
Evaluation of ventilatory efficiency during exercise in patients with idiopathic scoliosis undergoing spinal fusion.
STUDY DESIGN: A prospective evaluation of ventilatory function following spinal fusion in adolescent idiopathic scoliosis. OBJECTIVES: To prospectively evaluate pulmonary function, maximal oxygen uptake, and ventilatory efficiency during exercise in patients with adolescent idiopathic scoliosis before surgery and a minimum of 2 years postoperation. SUMMARY OF BACKGROUND DATA: For reasons that are unclear, patients with untreated adolescent idiopathic scoliosis tend to avoid aerobic exercise. Their reluctance may be the result of low ventilatory efficiency, as they often approach their ventilatory ceiling at maximum oxygen uptake despite forced vital capacities that are near normal. This inefficiency of ventilation with exercise may explain the reluctance of patients with scoliosis to pursue aerobic fitness. No study has evaluated the effect spinal fusion has on the ventilatory function of patients with scoliosis during exercise. METHODS: Forty-two patients with adolescent idiopathic scoliosis (36 female and 6 male) at an average age of 14 +/- 3 years (range 10-18 years) underwent spinal fusion. Twenty patients underwent a posterior spinal fusion alone, 20 an anterior spinal fusion alone, and 2 an anterior spinal fusion and posterior spinal fusion. The average Cobb measurement was 55 degrees (range 40-85 degrees). Pulmonary function values (forced vital capacity, total lung capacity, maximum voluntary ventilation), maximum oxygen uptake (VO2max), and ventilatory efficiency were obtained before surgery and a minimum of 2 years postoperation. RESULTS: For all patients, forced vital capacity percent predicted decreased from 88.1% to 81.4% (P < 0.0001). Total lung capacity also declined from 90.5% to 88.5% but was not statistically significant (P = 0.189). Percent predicted maximum oxygen uptake (VO2max) declined from 93.6% to 85.1% (P = 0.00029). Ventilatory efficiency, as measured by VEmax/maximum voluntary ventilation, improved from 0.76 to 0.68 (P = 0.005), whereas measured by VEmax/FEV1 x 40 was unchanged from 0.69 to 0.70 (P = 0.172) postoperation. The choice of operative approach [anterior (n = 20) versus posterior (n = 20)] or whether rib graft was harvested (n = 33) versus iliac crest graft (n = 7) did not change these results. CONCLUSION: Improvement in ventilatory efficiency during exercise does not occur in the majority of patients with adolescent idiopathic scoliosis following spinal fusion and thus cannot be relied on to foster increases in aerobic activity.
Adolescent↗
Chest physiotherapy after coronary artery bypass graft surgery--a comparison of three different deep breathing techniques.
The effectiveness of three deep breathing techniques was evaluated in 98 male patients after coronary artery bypass graft surgery in a randomized trial. The techniques examined were deep breathing with a blow bottle-device, an inspiratory resistance-positive expiratory pressure mask (IR-PEP) and performed with no mechanical device. Pulmonary function and roentgenological changes were evaluated. Four days post-operatively there were significantly decreased vital capacity, inspiratory capacity, forced expiratory volume in 1 second, functional residual capacity, total lung capacity and single-breath carbon monoxide diffusing capacity in all three groups (p < 0.0001). No major differences between the treatment groups were found, but the impairment in pulmonary function tended to be less marked using the blow bottle technique. The Blow bottle group had significantly less reduction in total lung capacity (p = 0.01) compared to the Deep breathing group, while the IR-PEP group did not significantly differ from the other two groups.
Aged↗
Lung and thorax development during adolescence: relationship with pubertal status.
The aim of the present study was to define reference values for lung volumes and the lung transfer factor for carbon monoxide (TL,CO) for an adolescent population using thoracic volume index (TVI) and an index of pubertal stage in order to account for the variation in growth pattern between adolescents. TVI, pubertal stage by Tanner scale (PST), time since menarche, functional residual capacity measured using the helium-dilution technique, vital capacity, total lung capacity and TL,CO measured using a steady-state method were determined in 51 males (aged 13-20 yrs; PST T3-T5) and 52 females (aged 13-18 yrs; PST T2-T4; all but three had already undergone menarche). In male adolescents, height, weight, TVI, lung volumes and TL,CO increased with age. This was not the case in female adolescents. In males, the TVI was the independent variable that best correlated with pulmonary volumes. In females, height was the independent variable that best correlated with pulmonary volumes. In both sexes, the variable that best correlated with TL,CO was PST, associated with height in males. This cross-sectional study provides prediction equations for lung volumes and the lung transfer factor for carbon monoxide taking into account thoracic volume index and pubertal stage. It shows that, in adolescent males, lung and thoracic development occurs during and until the end of puberty. Conversely, in adolescent females, lung development is almost finished following menarche.
Adolescent↗
Laminin fragment P1 in the sera of patients with pulmonary sarcoidosis.
Laminin is a noncollagenous component of the extracellular matrix in the alveolar wall and may play a role in the development of fibrotic lung disease. Serum levels of laminin fragment P1 as well as procollagen III peptide were determined in 28 patients with pulmonary sarcoidosis and 10 healthy controls using specific radioimmunoassays. The patients' results were compared with the clinical appearance, lung function values (vital capacity, total lung capacity, FEV1, transfer coefficient (KCO), and alveolar-arterial oxygen difference during exercise) and serum concentrations of angiotensin converting enzyme and soluble interleukin 2 receptor. Laminin levels in patients were significantly higher than in controls but always remained within normal limits. Although there was a tendency towards higher values in patients with active disease and with radiographic involvement, no significant correlation was found between laminin concentration and clinical, functional or biochemical data. In contrast, procollagen III N-terminal peptide concentrations were elevated in 19 of 28 patients and showed a weak but significant inverse correlation with parameters of restriction with significantly higher values in patients with active disease. In conclusion, serum levels of laminin fragment P1 are not elevated in pulmonary sarcoidosis and do not correlate with other parameters of the disease. Yet serum levels of procollagen III N-terminal peptide were associated with the degree of parenchymal involvement as expressed by functional disturbance and with active disease.
Adult↗
Influence of excessive weight loss on respiratory function. A study of obese patients following gastroplasty.
The influence of excessive weight loss, with decreased muscle mass, on pulmonary function was evaluated in 16 obese patients without clinical evidence of respiratory disease. Weight loss was induced with vertical banded gastroplasty. Six nonobese age-matched patients undergoing elective cholecystectomy acted as controls. Preoperative values for static and dynamic lung function variables and for pulmonary gas distribution and respiratory muscle strength were compared with postoperative values after approximately 10% and 18% weight reduction. Before gastroplasty the dominant abnormality of respiratory function was slight restrictiveness, with reduced lung volumes. Body weight and lean body mass decreased significantly during the study period, and respiratory muscle strength was significantly reduced after 10% weight loss. Lung function tests nevertheless showed significant increase of vital capacity, functional residual capacity, total lung capacity and maximal voluntary ventilation. No correlation was found between the reduction of respiratory muscle strength and that of lean body mass. The controls did not diminish the body weight after surgery and the lung volumes and respiratory muscle strength was not changed.
Adult↗
The effects of early pneumonectomy on the remaining pulmonary parenchyma.
To determine the age-related response of the remaining pulmonary parenchyma to lung resection, a matched set of 24 purebred beagle dogs underwent pneumonectomy at 6 to 10 weeks of age (group I) or at 1 year of age (group II). Eight unoperated adult beagles served as controls (group III). One year after pneumonectomy, pulmonary hemodynamics in group I were the same as those in older animals shortly after pneumonectomy and in normal control animals. Functional residual capacity, total lung capacity, single breath diffusing capacity for carbon monoxide, and static lung compliance were measured in all three groups while anesthetized and intubated. Lung volumes and diffusion capacity for carbon monoxide in group I did not differ significantly from those of control animals. Group I animals did have a lower lung compliance than the control group, but significantly greater than the group II adult pneumonectomy dogs. The adult pneumonectomy dogs (group II) had significantly lower values for lung volumes, diffusion capacity, and compliance when compared to the control group. Arterial blood gases were not significantly different among the groups. It is concluded that beagles undergoing early pneumonectomy have an increase of alveoli beyond the normal complement in the remaining lung with concomitant remodeling of the pulmonary capillary bed resulting in normal lung volumes, diffusing capacity, and gas exchange.
Age Factors↗
Importance of anti-lung antibody in farmer's lung disease.
The presence of anti-lung antibody was evaluated in 20 patients with farmer's lung disease. Antibody was found in 14. In patients with disease of less than five years' duration, there was no evidence of any significant differences in vital capacity, total lung capacity, diffusion capacity, and PaO2 between those with and without anti-lung antibody. However, in patients with disease of longer than five years' duration, the diffusion capacity was lower in the anti-lung antibody-positive group (p less than 0.05). The prevalence of abnormalities of vital capacity and diffusion capacity and fibrosis on chest roentgenograms was higher in those who had anti-lung antibody and disease of more than five years' duration. The study suggests that anti-lung antibody is present before permanent measurable physiologic abnormality occurs and may potentiate the pulmonary damage during subsequent episodes.
Adult↗
Pulmonary ventilation and mechanics in morbidly obese Zucker rats.
The obese Zucker rat, an autosomally genetic model of obesity, represents a good model of relatively early onset human obesity. Although factors associated with the control of metabolism and thermoregulation have been studied extensively in these animals, pulmonary mechanics and ventilation have not been documented and form the basis of this investigation. Studies were carried out in 16 obese and 18 lean female littermates (698 +/- 79 versus 304 +/- 24 g, p < 0.001). Pulmonary function, including lung volumes and respiratory system compliance, was evaluated in supine anesthetized animals. With the exception of residual volume, all other lung volumes, including function residual capacity, total lung capacity, expiratory reserve volume, and inspiratory capacity, were significantly reduced (p < 0.05 or better) in the obese phenotype compared with volumes in the lean littermates. Pressure-volume relationships of the intact respiratory system and the excised lung were also determined. Although lung compliance was similar between the phenotypes, respiratory system compliance was significantly lower (0.85 +/- 0.06 versus 0.67 +/- 0.09 ml/cm H2O, p < 0.01) in the obese rats. Oxygen consumption and ventilatory parameters (including respiratory rate, tidal volume, minute ventilation, inspiratory time, and expiratory time) were similar between phenotypes breathing room air, and the minute ventilation in response to hypoxia was similar in both groups. In marked contrast, obese animals exhibited a blunted ventilatory response to hypercapnia (221 +/- 38 versus 135 +/- 44 ml/min, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Effect of concurrent radiation therapy and chemotherapy on pulmonary function in patients with esophageal cancer: dose-volume histogram analysis.
PURPOSE: The pulmonary effects of concurrent radiation therapy and chemotherapy were studied in patients enrolled in a phase I trial for esophageal cancer. MATERIALS AND METHODS: Pulmonary function tests were performed prospectively before and after combined-modality therapy (oxaliplatin, 5-fluorouracil, and radiation therapy) in 20 patients with esophageal cancer. Cumulative and differential lung DVH analysis from 0 to 5400 cGy in 25-cGy intervals was performed for the last 15 patients. Correlation between radiation exposure in various dose ranges and percent reduction in pulmonary function tests was calculated as an exploratory analysis. RESULTS: Significant reductions in carbon monoxide diffusion capacity corrected for hemoglobin (12.3%) and total lung capacity (2.5%) were evident at a median of 15.5 days after radiation therapy. DVH analysis revealed that the single dose of maximum correlation between lung volume radiation exposure and lung function reduction was less than 1000 cGy for all pulmonary functions. The percent lung volume that received a total dose between 700 and 1000 cGy maximally correlated with the percent reductions in total lung capacity and vital capacity, and the absolute lung volume that received a total dose between 700 and 1000 cGy maximally correlated with the percent reductions in total lung capacity, vital capacity, and carbon monoxide diffusion capacity. DISCUSSION: Significant declines in carbon monoxide diffusion capacity and total lung capacity are evident immediately after the administration of conformal radiation therapy, oxaliplatin, and 5-fluorouracil for esophageal cancer. Other lung functions remain statistically unchanged. The percent or absolute lung volume that received a total dose between 700 and 1000 cGy may be significantly correlated with the percent decline of carbon monoxide diffusion capacity, total lung capacity, and vital capacity. These associations will be evaluated further in a follow-up study.
Antineoplastic Combined Chemotherapy Protocols↗
Effect of pulmonary emphysema on diaphragm capillary geometry.
In emphysema, the diaphragm shortens by losing sarcomeres. We hypothesized that unless capillaries undergo a similar shortening, capillary geometry must be altered. Without quantifying this geometry, capillary length and surface area per fiber volume, which are critical measurements of the structural potential for blood-tissue exchange, cannot be resolved. Five months after intratracheal elastase (E) or saline (control; C) instillation, diaphragms from male Syrian golden hamsters were glutaraldehyde perfusion fixed in situ at reference lung positions (residual volume, functional residual capacity, total lung capacity) to provide diaphragms fixed over a range of sarcomere lengths. Subsequently, diaphragms were processed for electron microscopy and analyzed morphometrically. Emphysema increased lung volume changes from -20 to 25 cmH2O airway pressure (i.e., passive vital capacity) and excised lung volume (both P < 0.001). In each region of the costal diaphragm (i.e., ventral, medial, dorsal), sarcomere number was reduced (all P < 0.05). Capillary-to-fiber ratio increased (C = 2.2 +/- 0.1, E = 2.8 +/- 0.1; P < 0.01) and fibers hypertrophied (C = 815 +/- 35, E = 987 +/- 67 microns2; P < 0.05; both values at 2.5 microns sarcomere length). Capillary geometry was markedly altered by the loss of sarcomeres in series. Specifically, the additional capillary length derived from capillary tortuosity and branching was increased by 183% at 2.5 microns sarcomere length compared with C values (C, 359 +/- 43; E, 1,020 +/- 158 mm-2, P < 0.01). This significantly increased total capillary length (C, 3,115 +/- 173; E, 3,851 +/- 219mm-2 at 2.5 microns, P < 0.05) and surface area (C, 456 +/- 13; E, 519 +/- 24 cm-1, P < 0.05) per fiber volume. Thus emphysema substantially alters diaphragm capillary geometry and augments the capillary length and surface area available for blood-tissue exchange.
Animals↗
Variability, reproducibility and observer difference of body plethysmographic measurements.
The variability (coefficient of variation of five consecutive measurements), reproducibility (difference of results at 1 h and 24 h), and interobserver difference (independent reading of the tracings by two observers) of airways resistance (Raw) and static lung volumes (residual volume, functional residual capacity, total lung capacity) using a body plethysmograph were assessed in 14 healthy subjects and in 25 patients with various respiratory disorders. The variability was low for TLC (4-5%), moderate for FRC (7-8%) and high for Raw (28%). No significant changes of Raw or lung volumes were found for the groups at 1 h and 24 h. Between observers, a slight difference existed for FRC and Raw in normal subjects; the difference was higher (4.5% for FRC and 11% for Raw) and became significant in patients. The overestimation of Raw by observer 2 as compared to observer 1 was more important at larger values. The present findings call for caution when pooling results obtained by several observers in large-scale studies, or when comparing figures obtained by different technicians in the pulmonary function laboratory.
Adult↗