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PubMed1995

Cardiac and respiratory function after bone marrow transplantation in children with leukaemia.

Late cardiac and respiratory function changes were evaluated in children surviving disease-free more than 2 years after bone marrow transplantation (BMT) performed for haematological malignancies. Forty-one children received allogeneic and 10 autologous BMT. In all cases studied shortening fraction (SF) was always within normal limits from before BMT up to 4 years after BMT. SF, though still normal, was slightly lower in the group with higher pre-BMT cumulative anthracycline dose. Twenty-eight children underwent respiratory function tests regularly at all scheduled times (pre-BMT, +6 months, +1, +2, +3, +4 years after BMT). Vital capacity and total lung capacity showed a slight continuous decrease which was significant at 4 years after BMT (P = 0.015 and P = 0.003 respectively). The decline of forced expiratory volume in 1 s observed 1 year after BMT (P = 0.002) was roughly maintained over time. However, no children complained of symptoms attributable to respiratory dysfunction, and all indices studied were always within normal limits in almost all patients. So far late cardiac and lung changes following BMT in children seem to be negligible. However, whether such abnormalities could further worsen and impair adult quality of life remains to be ascertained.

Adolescent↗
PubMed1998

Diagnostic role of residual volume in paediatric patients with chronic symptoms of the lower airways.

In bronchial asthma, measurement of absolute lung volumes may reveal lung dysfunction more readily than forced expiratory spirometry. Sixty-one children (aged 4-16 years) with mild to moderate bronchial asthma and 35 children (aged 7-16 years) with other symptoms of the lower airways (OSLA) were studied, and the plethysmographic results were compared with data obtained from 36 healthy volunteers aged 6-16 years. In the first test session, repeatability of forced expiratory volume in one second (FEV1), forced vital capacity (FVC), residual volume (RV), functional residual capacity (FRC) and total lung capacity (TLC) were good. Control subjects were also tested the next day, and intra-subject variability of repeat pulmonary function testing was in the normal range. The FEV1/FVC ratio was significantly higher in control subjects than in patients with asthma or OSLA, but only the decrease in RV after bronchodilator challenge separated patients with asthma from patients with OSLA. Changes in FEV1 and RV after bronchodilator challenge had a significant, although low, inverse correlation. An increase of > or = 5% in FEV1 had a positive predictive value of 44% and a negative predictive value of 68% for the clinical diagnosis of bronchial asthma; for a decrease of > or = 24% in RV, the figures were 86% and 71% respectively. The support of baseline absolute lung volumes on clinical decision-making is not necessarily great. Bronchodilator response, particularly in RV, is more pertinent and may enhance the detection of reversible lung dysfunction.

Adolescent↗
PubMed2005

Ventilation and exercise performance after phrenic nerve and multiple intercostal nerve transfers for avulsed brachial plexus injury.

BACKGROUND: Diaphragmatic excursion, lung function, exercise performance, and clinical symptoms have not been previously described in patients after phrenic nerve transfer (PNT) and/or multiple intercostal nerve transfer (MIT) for the repair of avulsed brachial plexus injury (ABPI) to prevent functional musculoskeletal impairment in the shoulder. SETTING: A university-based hospital. METHODS: Dyspnea scores, chest ultrasonography to assess diaphragmatic excursion, and pulmonary function testing were performed to assess ventilation in patients sustaining trauma to their brachial plexus. In addition, cardiopulmonary exercise testing was also performed. These studies were obtained prior to surgical intervention, and were repeated postoperatively at 6, 12, 18, 24, and 36 months. The results obtained preoperatively were compared to those obtained throughout the postoperative monitoring period. RESULTS: This study demonstrates that the PNT-MIT procedure results in permanent ipsilateral diaphragmatic paralysis accompanied by an approximately 8% decrease in inspiratory capacity, FVC, and total lung capacity. There was also an 11% increase in diffusing capacity noted during the period between 6 months and 3 years after PNT-MIT procedure. Despite these measurable changes in lung function, the patients reported amelioration of their dyspnea complaint within 6 months of undergoing this procedure, which was due mainly to an improvement in their cardiovascular exercise performance related to increased daily activity. CONCLUSIONS: This study demonstrates that the PNT-MIT procedure is a safe method for the restoration of drop shoulder incurred by ABPI. This surgery has an impact on measurable diaphragmatic and lung function but with minimal impact in terms of postoperative clinical symptoms and exercise performance.

Adult↗
PubMed1983

Comparison of total lung diffusion capacity and the membrane component of diffusion capacity as determined by physiologic and morphometric techniques.

Morphometric estimates of diffusion capacity have traditionally been calculated for oxygen (DLO2) while physiologic techniques have been used to determine diffusion capacity for carbon monoxide (DLCO). Morphometric estimates of DLCO and Dm were determined for carbon monoxide so that the results can be directly compared to those obtained using physiologic techniques. Multiple gas rebreathing techniques were used to measure total lung diffusion capacity (DLCO), membrane component of diffusion capacity (Dm) and pulmonary capillary blood volume (Vc) in five anesthetized dogs. After the rebreathing measurements were made, the lungs were inflation fixed with glutaraldehyde and subjected to morphometric analysis. The morphometric estimate of diffusion capacity was three times higher than the physiologic estimate. The major components of diffusion capacity, Dm and theta Vc were found to be of approximately equal size when measured physiologically (Dm = 34 and theta Vc = 27 ml X min-1 X mm Hg-1). In contrast, the morphometric estimate of Dm was about six times higher than the morphometric estimate of theta Vc. The widely different ratios of the two major subcomponents of the total lung diffusion capacity as measured by these two different techniques suggest that the same lung function is not being accurately measured by at least one of these two techniques. Differences in results for DLCO cannot be explained by differences in the physiologic state of the animal at the time the measurement was made. Morphometric analysis predicts that Vc is the major term affecting the value of DLCO whereas the physiologic techniques predict that both Dm and Vc contribute substantially to the value of DLCO.

Animals↗
PubMed1995

Effect of size (mis)matching in clinical double-lung transplantation.

Current United Network for Organ Sharing policy requires listing lung transplant recipients with an acceptable donor weight range, but lung size is a function of height, age, sex, and race. Frequently, lung transplant recipients are underweight, which results in a large discrepancy between donor and recipient weights. We reviewed our experience with size discrepancy between donors (D) and recipients (R) of 49 double-lung transplant (DLTX) procedures since July 1990. Pneumoreduction procedures were performed in 11 recipients of lungs judged to be too large at the time of DLTX (right middle lobectomy, 2; lingulectomy, 2; both, 6; right middle lobectomy and bilateral apical resections, 1). Predicted forced vital capacity (FVC) and total lung capacity (TLC) of donors and recipients were calculated. Donors were larger than recipients in general (D:R height = 1.02; D:R weight = 1.46), and, as a result, recipient-predicted lung volumes were smaller than donor-predicted lung volumes (D:R FVC = 1.1; D:R TLC = 1.1). Recipients undergoing pneumoreduction procedures had a significantly greater size discrepancy between donors and recipients; thus, both the ratio of D:R and the difference between D and R predicted FVC and TLC were significantly greater among recipients who underwent pneumoreduction, compared with nonreduced recipients. For recipients in the pneumoreduction group, predicted FVC and TLC were recalculated, with a proportionate amount subtracted based on the number of pulmonary segments removed. When the "corrected" FVC and TLC of the donors were compared with recipient-predicted FVC and TLC, there was no longer any significant difference between reduced and non-reduced groups, which implies that visual estimate of size mismatch at surgery is an accurate measure of size discrepancy. Post-DLTX spirometry showed identical improvement in FVC in patients who had pneumoreduction and those who did not, and survival at 6 months was identical in both groups. We conclude that pneumoreduction had no adverse effect on survival or post-DLTX spirometry, allowing safe use of larger donors in small recipients. Also, because lung size is more a function of height than weight, this study challenges the United Network for Organ Sharing practice of listing recipients with an acceptable donor weight range.

Adolescent↗
PubMed1969

Maximum expiratory flow rates in induced bronchoconstriction in man.

We evaluated changes of maximum expiratory flow-volume (MEFV) curves and of partial expiratory flow-volume (PEFV) curves caused by bronchoconstrictor drugs and dust, and compared these to the reverse changes induced by a bronchodilator drug in previously bronchoconstricted subjects. Measurements of maximum flow at constant lung inflation (i.e. liters thoracic gas volume) showed larger changes, both after constriction and after dilation, than measurements of peak expiratory flow rate, 1 sec forced expiratory volume and the slope of the effort-independent portion of MEFV curves. Changes of flow rates on PEFV curves (made after inspiration to mid-vital capacity) were usually larger than those of flow rates on MEFV curves (made after inspiration to total lung capacity). The decreased maximum flow rates after constrictor agents are not caused by changes in lung static recoil force and are attributed to narrowing of small airways, i.e., airways which are uncompressed during forced expirations. Changes of maximum expiratory flow rates at constant lung inflation (e.g. 60% of the control total lung capacity) provide an objective and sensitive measurement of changes in airway caliber which remains valid if total lung capacity is altered during treatment.

Acetylcholine↗
PubMed1978

Pulmonary function studies in sickle cell anaemia.

Pulmonary studies including the measurements of single-breath diffusing capacity for carbon monoxide (DL); Forced Vital Capacity (FVC); Residual Volume (RV) and Total Lung Capacity (TLC) were carried out in forty normal subjects; twelve patients with homozygous sickle cell anaemia and five patients with iron deficiency anaemia due to hookworm infestation. Normal subjects had a mean haemoglobin content of 13.4 g per 100 ml and a mean DL value of 28 ml/min/mmHg. In the patients with hookworm anaemia, the mean haemoglobin was 4.9 g per 100 ml while the mean DL value was 9 ml/min per mmHg. Patients with sickle cell anaemia had a mean haemoglobin content of 6.2 g/100 ml yet the mean DL value was 20 ml/min per mmHg. The study showed that patients with homozygous sickle cell anaemia have a disproportionately high DL value in the presence of severe anaemia which might be due to a chronically expanded pulmonary capillary blood volume as a compensatory mechanism to maintain an appropriate level of DL.

Adolescent↗
PubMed1987

Optimal combinations of lung function tests in the detection of various types of early lung disease.

The ability to detect early lung disease with different combinations of lung function tests was assessed by discriminant analysis. A number of lung function tests were performed in 224 never-smokers, 232 smokers, 111 pneumoconiotic subjects and 137 asthmatic patients. The discriminatory capacities of different combinations of test variables are presented. For detecting lung damage induced by tobacco smoke, a combination of the transfer factor and the slope of the alveolar plateau (phase III) increased the sensitivity from 18% to 32% at a specificity of 95%, compared with phase III alone. Dynamic spirometry did not add to the discriminatory capacity. Patients with asthma could be separated from reference subjects by airway resistance, Phase III or a combination of variables in dynamic spirometry. Pneumoconiotic subjects were best identified by a combination of the transfer factor, volumic compliance and phase III. Closing capacity divided by total lung capacity (TLC) and FEV1/TLC further improved the discrimination between different subgroups.

Airway Resistance↗
PubMed1999

The effect of thoracentesis on lung function and transthoracic electrical bioimpedance.

This study aimed to determine the relationship between improvement in lung function and changes in transthoracic electrical bioimpedance (TEB) after thoracentesis in patients with pleural effusions. Fifteen patients with pleural effusions due to either malignant (n = 8) or cardiac (n = 7) diseases were included. Pulmonary function was assessed before and after thoracentesis. During thoracentesis the patients were monitored with TEB. Using linear correlation analysis, the increases for each litre of aspirated thoracic fluid were: forced expiratory volume in 1 s (FEV1) 0.261; forced vital capacity (FVC) 0.331; total lung capacity (TLC) 0.58; and the lung diffusing capacity (DLCO); 2.4 ml min-1 mmHg-1. Baseline impedance increased by 2.3 Ohm l-1 aspirated thoracic fluid. The relative increase in baseline impedance was twice as high for patients with cancer as for patients with heart failure (P < 0.05). We found only minor changes in systolic blood pressure and mean arterial pressure. The improvements in diffusing capacity, airflow, and lung volumes after thoracentesis are correlated to an increase in baseline impedance, but changes are dependent on the primary disease.

Aged↗
PubMed2005

[Evaluation of dynamic hyperinflation parameters and exercise capacity at maximal exercise in patients with COPD].

Hyperinflation is an important limiting factor for exercise performance in patients with chronic obstructive pulmonary disease (COPD). Hyperinflation can be determined by measuring residual volume (RV), functional residual capacity (FRC), and total lung capacity (TLC) at rest, and by measuring inspiratory capacity (IC) and end-expiratory lung volume (EELV) at maximal exercise. This study aimed to evaluate changes in hyperinflation parameters on maximal exercise in subjects with COPD. Patients with clinically stable COPD (n= 43) and healthy controls (n= 14) were included. Subjects performed pulmonary function tests and an incremental exercise test on cycle ergometry. Statistically significant differences (p< 0.05) were found regarding exercise test parameters including exercise duration, maximum oxygen uptake, breathing reserve, maximum minute ventilation, and breathing pattern between groups. There was significant increase in EELV (p< 0.05) and decrease in IC (p< 0.05) at maximum exercise when hyperinflation parameters were compared at baseline and maximum exercise. Our results showed that hyperinflation was evident at maximal exercise, although there were no hyperinflation findings at rest in subjects with COPD. We believe that in patients with COPD, it is better to evaluate hyperinflation at maximal exercise than at rest.

Exercise↗
PubMed2002

Unilateral expiratory airflow obstruction during forced exhalation.

We present a case of unilateral airflow obstruction during forced exhalations. The patient presented with episodic dyspnea and wheezing, particularly when he lay in the right lateral decubitus position. Spirometry revealed symmetric, marked reductions in forced expiratory volume in the first second and forced vital capacity values, while plethysmography demonstrated a near-normal total lung capacity. Bronchoscopy revealed a polypoid lesion in the right main bronchus, of which biopsy specimens demonstrated adenoid cystic carcinoma. Following a right pneumonectomy, total lung capacity was markedly reduced; interestingly, however, spirometry was essentially unchanged. This case is an elegant illustration of the effects of respiratory maneuvers and body position on airway caliber.

Airway Obstruction↗
PubMed1993

Lung size matching for double lung transplantation based on the submammary thoracic perimeter. Accuracy and functional results. The Joint Marseille-Montreal Lung Transplant Program.

The present study evaluates the accuracy of submammary thoracic perimeter for lung size matching between donor and recipient and analyzes the influence of donor lung size discrepancies on functional outcome after double lung transplantation. The population is composed of 18 double lung graft recipients, 16 of whom had cystic fibrosis. The lung size match was assessed by comparison of predicted total lung capacity of donor and recipient: five patients were matched in a 10% confidence interval; four received smaller lungs, and nine received larger ones. The functional outcome was assessed with the spirometric values measured at 3 and 6 months after transplantation. The final functional result was not influenced by the lung size (r = 0.142 for total lung capacity; r = 0.372 for vital capacity; r = 0.378 for forced expiratory volume in 1 second). For larger lungs the final result tended to the recipient's predicted, whereas for smaller lungs, spirometry tended to the donor's predicted (r = 0.906 for total lung capacity; r = 0.875 for vital capacity; r = 0.874 for forced expiratory volume in 1 second). The thoracotomy effect, that is, restrictive syndrome at 3 months that resolves at 6 months, was not correlated with the lung size (r = 0.07 for total lung capacity; r = 0.436 for vital capacity). It is concluded that respiratory functional result is not affected by larger lungs; despite the wide range of error, the submammary thoracic perimeter appeared to be a satisfactory selection parameter in this group of patients.

Adolescent↗
PubMed2001

[Relation between neck accessory inspiratory muscle electromyographic activity and lung volume].

Years ago it was reported that, as lung volume increased, there was a corresponding increase in scalene EMG activity (Raper et al. J Appl Physiol 21: 497-502, 1966). Otherwise, the relationship between changing lung volume and the EMG of the respiratory muscles has not been defined. We therefore inserted fine wire electrodes into the scalene (SCLN), sternocleidomastoid (STERNO), and trapezius (TRAPEZ) muscles in 6 healthy subjects under direct vision using high-resolution ultrasound. Maximum EMG activity (EMGmax) was obtained for each muscle by a variety of respiratory and postural maneuvers. Then, in the standing posture, air flow, raw and moving average EMG signals were sampled and input to a computer during quasi-static inspiration from functional residual capacity (FRC) to total lung capacity (TLC). We found that the relationship between EMG and lung volume for SCLN, but not for STERNO or TRAPEZ, was expressed by exponential curves. The onset of SCLN, STERNO and TRAPEZ EMG occurred at 13.3 +/- 7.4 (mean +/- SE), 67.8 +/- 14.6, and 89.2 +/- 3.9% of inspiratory capacity. The EMG of SCLN, STERNO, TRAPEZ, reached 85.7 +/- 2.6, 60.7 +/- 8.6, and 11.8 +/- 5.2% of EMGmax, respectively, at TLC. We conclude that: 1) SCLN is the most, and TRAPEZ the least, active neck accessory inspiratory muscle, while STERNO is intermediate, and 2) there is a lung volume dependency of the neck accessory muscle EMG activity.

Adult↗
PubMed1993

An algorithm for measurement of expiratory flow rate parameters on the partial expiratory flow-volume curve.

Partial expiratory flow-volume (PEFV) curves are a useful tool in airway challenge studies, but unlike the maximal expiratory flow-volume (MEFV) curve, lung function parameters require manual calculation from the flow-volume tracing. We describe an algorithm written in QuickBASIC that analyzes a PEFV curve superimposed on a MEFV curve by (1) identifying the PEFV curve, (2) locating the maximal expiratory flow at the point on the PEFV curve that corresponds to 60% of the baseline forced vital capacity (FVC) below total lung capacity (TLC), termed MEF40%(P), and (3) identifying the size of the PEFV curve along the TLC axis. A report of these parameters is also provided. This algorithm was validated using flow-volume curves from a clinical study in which eight subjects performed two sets of MEFV and PEFV curves separated by approximately 1 hr. Paired comparison of MEF40%(P) determined by the algorithm and two independent manual calculations correlated strongly and yielded no statistically significant differences between the two methods. We conclude that this algorithm provides rapid and accurate determinations of PEFV parameters.

Algorithms↗
PubMed1980

Elastic recoil changes in early emphysema.

An attempt was made to determine if emphysema and static lung recoil were related in a group of 65 excised human lungs. We studied 23 normal lungs, 24 lungs with an emphysema score of 5 or less, and 18 lungs with an emphysema score greater than 5. A comparison of the percentage of predicted elastic recoil revealed that both emphysema groups were significantly different from normal lungs. In addition, the total lung capacities were significantly different between the three groups. In the group with an emphysema score greater than 5 we found a linear negative correlation between the extent of emphysema and percent of predicted elastic recoil at 90% total lung capacity (r = -0.696, p < 0.01). We found a negative correlation between the percentage of predicted elastic recoil and the lung volume (r = -0.612, p < 0.01). We conclude that a significant loss of elastic recoil and a significant increase in total lung capacity occurs in the early stages of emphysema.

Adolescent↗
PubMed1988

Inspiratory muscles during exercise: a problem of supply and demand.

The capacity of inspiratory muscles to generate esophageal pressure at several lung volumes from functional residual capacity (FRC) to total lung capacity (TLC) and several flow rates from zero to maximal flow was measured in five normal subjects. Static capacity was 126 +/- 14.6 cmH2O at FRC, remained unchanged between 30 and 55% TLC, and decreased to 40 +/- 6.8 cmH2O at TLC. Dynamic capacity declined by a further 5.0 +/- 0.35% from the static pressure at any given lung volume for every liter per second increase in inspiratory flow. The subjects underwent progressive incremental exercise to maximum power and achieved 1,800 +/- 45 kpm/min and maximum O2 uptake of 3,518 +/- 222 ml/min. During exercise peak esophageal pressure increased from 9.4 +/- 1.81 to 38.2 +/- 5.70 cmH2O and end-inspiratory esophageal pressure increased from 7.8 +/- 0.52 to 22.5 +/- 2.03 cmH2O from rest to maximum exercise. Because the estimated capacity available to meet these demands is critically dependent on end-inspiratory lung volume, the changes in lung volume during exercise were measured in three of the subjects using He dilution. End-expiratory volume was 52.3 +/- 2.42% TLC at rest and 38.5 +/- 0.79% TLC at maximum exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1975

Appraisal of a new test: Between-technician variation in the measurement of closing volume.

To determine the between-technician variation in the measurement of closing volume, 24 subjects were divided into 3 blocks of 8 subjects each. Each block was then tested by a pair of technicians. Each of the 3 technicians involved in the study tested 16 subjects. It was later necessary to reject the tracings of 2 subjects in one of the 3 blocks, leaving 22 for analysis. The N2 method of determining closing volume was used. The statistical analysis was performed separately on the following measures derived from the tracings: expired vital capacity, planimetry of the area under the curve, total lung capacity, closing volume as a per cent of expired vital capacity, and closing capacity as a per cent of total lung capacity. All tracings were assessed by each technician. Two separate analyses of variance were then carried out to determine, respectively, the components of variance in the administration of the test and in the interpretation of the tracings. Because different persons were able to administer the test the same way, it seems that closing volume poses no problem in administration, provided that instructions as to how to perform the test are closely followed. In the interpretation of the tracings, significant differences were found for all measures, except planimetry; however, not all of these have the same practical implications. Some tracings were found "difficult" to interpret and contributed more to the over-all variation than did others. When making use of a new test in a population study, the between-technician variation should be determined before the study is begun.

Humans↗
PubMed1976

Reversible restrictive lung disease stimulating asthma.

A young adult woman presented with spontaneous and exercise-induced episodic dyspnea without wheezing. During dyspneic episodes all static lung volumes decreased markedly, the inspiratory capacity fell from 3.0 to 1.1 litres and total lung capacity from 5.3 to 2.6 litres. Airway resistance (Raw) remained normal, and maximal expiratory flows at low absolute lung volume actually increased. Static compliance decreased from 0.153 to 0.077 litre/cmH2O, and the elastic recoil increased from 2.8 to 4.8 cmH2O at 50% of baseline total lung capacity when dyspneic. Upstream airway resistance (Rus) remained unchanged, 1.7 cmH2O/litre/sec. All physiologic variables indicated a reversible restrictive process exists, the origin of which is unclear. It is concluded that the episodic increase in elastic recoil properties results in [1] loss of volume primarily in the alveolar ducts and sacs, [2] preservation of normal Rus by an increase in driving pressure, and [3] maintenance of normal Raw by stabilization of larger airways.

Adult↗