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At least 505 records · Page 28Linked to original sources
PubMed1981

Pulmonary function test criteria for operability and pulmonary resection.

Pulmonary function criteria for pulmonary resection, other than pneumonectomy, have not been previously described. A series of 500 consecutive pulmonary resections to which specific pulmonary function criteria were applied in determining the amount and the extent of feasible resection of the lung are presented. By application of these criteria, an accurate assessment of the type and extent of pulmonary resection a patient can tolerate without expected mortality can be made. With utilization of these criteria, the operative mortality for segmental resection was 0.2 per cent; for lobectomy, zero per cent, and for pneumonectomy, 4.4 per cent.

Adolescent↗
PubMed1980

Effects of ozone on symptoms and cardiopulmonary function in a flight attendant surrogate population.

Two studies were conducted to ascertain the lowest ozone concentration threshold for statistically significant adverse effects on cardiopulmonary function and symptoms in male and female surrogates of the flight attendant population. Both studies simulated in-flight environmental conditions at 1,829 m mean sea level (MSL) chamber altitude. The ozone exposures were 0.2 parts per million by volume (ppmv) for 4 h in the first study and 0.3 ppmv for 3 h in the second study. Each subject was similarly exposed to air only (no ozone) on another occasion. Treadmill exercise, equivalent to workloads of on-duty flight attendants, was performed at altitude. Cardiorespiratory measurements were made during ozone exposure, whereas spirometry and symptom assessments were made immediately before and after exposure. The ozone threshold for reversible adverse effects on symptoms and spirometry function was reached by a 3-h exposure to 0.3 ppmv. The data suggest a greater symptomatic sensitivity to ozone in females.

Adult↗
PubMed1980

A simple office spirometer for the pediatrician.

A comparative study of a new, simple, pneumatic, direct-recording office spirometer versus a long-accepted, water-sealed, water-filled spirometer was performed on 103 patients ranging from four to 20 years of age. Good correlation between the two spirometers was seen through a wide range of values for forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and forced expiratory flow during 25% to 75% of forced vital capacity and FEV1/FVC.

Adolescent↗
PubMed1994

Improved detection of abnormal respiratory function using forced expiration from raised lung volume in infants with cystic fibrosis.

The raised volume rapid thoracic compression (RVRTC) technique is a recently developed method of measuring lung function in infants. The measurements of forced expiratory volume-time (FEVt) parameters from raised lung volumes have been shown to be less variable than maximal flow at functional residual capacity (VmaxFRC), obtained from the conventional rapid thoracic compression (RTC) technique. Measurements of VmaxFRC are highly variable, and may not be sensitive enough to detect a difference between normal infants and infants with cystic fibrosis (CF). The aim of this study was to determine whether the raised volume rapid thoracic compression technique could detect abnormal lung function in a group of CF infants with no current respiratory symptoms. Twelve CF infants were studied (median age 10.5 months, range 3-18 months), and compared to normative data collected previously on 26 healthy infants (median age 14 months, range 3-23 months). We found that VmaxFRC failed to detect any difference between the two groups. CF infants had significantly smaller FEV0.5 and FEV0.75 measurements at a lung volume set by 17.5 cmH2O predetermined inflation pressure (PP) both as raw values and when expressed as percentage predicted. We conclude that the raised volume rapid thoracic compression technique is a sensitive tool, able to detect abnormal lung function in infants with cystic fibrosis. This abnormality was not demonstrated by measurements derived from the conventional rapid thoracic compression technique in the tidal volume range.

Cystic Fibrosis↗
PubMed1994

[Error factors in spirometry].

Spirometry is the more frequently used method to estimate pulmonary function in the clinical laboratory. It is important to comply with technical requisites to approximate the real values sought as well as adequate interpretation of results. Recommendations are made to establish: 1--quality control 2--define abnormality 3--classify the change from normal and its degree 4--define reversibility. In relation to quality control several criteria are pointed out such as end of the test, back-extrapolation and extrapolated volume in order to delineate most common errors. Daily calibration is advised. Inspection of graphical records of the test is mandatory. The limitations to the common use of 80% of predicted values to establish abnormality is stressed. The reasons for employing 95% confidence limits are detailed. It is important to select the reference values equation (in view of the differences in predicted values). It is advisable to validate the selection with local population normal values. In relation to the definition of the defect as restrictive or obstructive, the limitations of vital capacity (VC) to establish restriction, when obstruction is also present, are defined. Also the limitations of maximal mid-expiratory flow 25-75 (FMF 25-75) as an isolated marker of obstruction. Finally the qualities of forced expiratory volume in 1 sec (VEF1) and the difficulties with other indicators (CVF, FMF 25-75, VEF1/CVF) to estimate reversibility after bronchodilators are evaluated. The value of different methods used to define reversibility (% of change in initial value, absolute change or % of predicted), is commented. Clinical spirometric studies in order to be valuable should be performed with the same technical rigour as any other more complex studies.

Adolescent↗
PubMedDate not supplied

[Changes of static and dynamic characteristics of external respiration in divers after short-term dives down to 100 m].

In a series of short (up to 45 min without considering time of decompression) dives (SD) at depths down to 100 m under conditions of the Barentsev Sea five professional deep-sea divers were examined. In dives down to 40 m compressed air was used as breathing media, in dives to 60, 80 and 100 m--nitrogen-heliox mixture. Before the SD series the volume and velocity lung variables at rest and during forced expiration in air and heliox media were measured between separate SDs and on the 3rd day after the end of decompression with dive to 100 m, using computer spiro- and pneumotachometry methods. Bronchospastic syndrome, playing the leading role in the development of transient isolated or generalized airway obstruction, was shown to be evoked in divers during conduction of SD series. Obstructive phenomena are presumed to be connected with elastic properties' disturbance of lung tissue and development of expiratory collapse; they might cause continuous lung dilatation.

Adult↗
PubMed1994

[Usefulness of peak expiratory flow measurements in assessing degree of bronchial obstruction in patients with chronic obstructive lung diseases].

An analysis was carried of relations between PEF measurements and FEV1 values and between PEF and FEF25-75 in 130 patients with COLD (48 females and 82 males). PEF was assessed using the Wright peak flow meter, while FEV1 and FEF25-75 from the spirographic curve. A positive linear correlation was found between PEF and FEV1 in absolute values, % predicted and standardised residuals (r = 0.91, r = 0.87, p < 0.001). Diagnostic sensitivity of PEF in detecting bronchial obstruction was 82%, while the specificity was 85%. The weakest correlation was found between PEF and FEV1 in standardised residuals of 41 patients with PEF between 50% and 79% predicted (r = 0.41, p < 0.05). In this subgroup of patients, twenty one (51%) had normal FEV1, and twenty (49%) low FEV1 values. Measurements of PEF despite a strong correlation with FEF25-75 did not allow to single out cases without small airway involvement, because in 28% of the patients with PEF 100% predicted lowered FEF25-75 were noted. In 97% of patients with PEF values 80% predicted abnormal low FEF25-75 were demonstrable.

Adult↗
PubMed1994

[Effect of vaporizing high doses of ipratropium bromide on lung ventilation in patients with chronic obstructive pulmonary disease and bronchial asthma].

Authors compared efficacy of high Atrovent doses and Salbutamol on pulmonary ventilation. Examinations were performed in 20 patients with BA and 20 patients with COPD. Each drug was given on separate days in increasing doses (0.04; 0.25 and 0.5 mg) of Atrovent and 0.2 mg of Salbutamol. Bronchodilatation was assessed by measurement of FEV1; FEF25%, FEF50%, FEF75%. Maximal effect in patients with COPD was reached with doses of 0.25 and 0.5 mg of Atrovent (delta FEV1(%) +22). Salbutamol and 0.04 mg of Atrovent were significantly less effective. In patients with BA Salbutamol (delta FEV1(%) +49) are likely to be more effective bronchodilator an Atrovent (delta FEV1(%) +26).

Albuterol↗