The Best Peak Expiratory Flow Is Flow-Limited and Effort-Independent in Normal Subjects

2002 ◽  
Vol 165 (9) ◽  
pp. 1304-1308 ◽  
Author(s):  
Claudio Tantucci ◽  
Alexandre Duguet ◽  
Pietro Giampiccolo ◽  
Thomas Similowski ◽  
Marc Zelter ◽  
...  
Keyword(s):  
Peak Expiratory Flow ◽  
Normal Subjects ◽  
Expiratory Flow

scholarly journals Peak Expiratory Flow in Normal Subjects

BMJ ◽  
1973 ◽  
Vol 3 (5874) ◽  
pp. 282-284 ◽  
Author(s):  
I. Gregg ◽  
A. J. Nunn
Keyword(s):  
Peak Expiratory Flow ◽  
Normal Subjects ◽  
Expiratory Flow

Peak flowmeter resistance decreases peak expiratory flow in subjects with COPD

2000 ◽  
Vol 89 (1) ◽  
pp. 283-290 ◽  
Author(s):  
Martin R. Miller ◽  
Ole F. Pedersen
Keyword(s):  
Peak Expiratory Flow ◽  
Healthy Subjects ◽  
Normal Subjects ◽  
Chronic Obstructive ◽  
Flow Limitation ◽  
Added Resistance ◽  
Elastic Recoil ◽  
Obstructive Pulmonary Disease ◽  
Thoracic Gas Volume ◽  
Expiratory Flow

Previous studies have shown that the added resistance of a mini-Wright peak expiratory flow (PEF) meter reduced PEF by ∼8% in normal subjects because of gas compression reducing thoracic gas volume at PEF and thus driving elastic recoil pressure. We undertook a body plethysmographic study in 15 patients with chronic obstructive pulmonary disease (COPD), age 65.9 ± 6.3 yr (mean ± SD, range 53–75 yr), to examine whether their recorded PEF was also limited by the added resistance of a PEF meter. The PEF meter increased alveolar pressure at PEF (Ppeak) from 3.7 ± 1.4 to 4.7 ± 1.5 kPa ( P = 0.01), and PEF was reduced from 3.6 ± 1.3 l/s to 3.2 ± 0.9 l/s ( P = 0.01). The influence of flow limitation on PEF and Ppeak was evaluated by a simple four-parameter model based on the wave-speed concept. We conclude that added external resistance in patients with COPD reduced PEF by the same mechanisms as in healthy subjects. Furthermore, the much lower Ppeak in COPD patients is a consequence of more severe flow limitation than in healthy subjects and not of deficient muscle strength.

Circulating histamine and eosinophil cationic protein levels in nocturnal asthma

1992 ◽  
Vol 83 (2) ◽  
pp. 227-232 ◽  
Author(s):  
Michael F. Fitzpatrick ◽  
Thomas MacKay ◽  
Carol Walters ◽  
Po-Chun Tai ◽  
Martin K. Church ◽  
...  
Keyword(s):  
Peak Expiratory Flow ◽  
Flow Rate ◽  
Protein Level ◽  
Peak Expiratory Flow Rate ◽  
Eosinophil Cationic Protein ◽  
Normal Subjects ◽  
Cationic Protein ◽  
Nocturnal Asthma ◽  
Asthmatic Patients ◽  
Expiratory Flow

1. To investigate the role of mast cells and eosinophils in the pathogenesis of nocturnal asthma, the plasma methylhistamine concentration, serum eosinophil cationic protein level and peak expiratory flow rate were measured 2-hourly for 24 h in 10 patients with nocturnal asthma and in 10 healthy control subjects. Nocturnal asthma was defined as at least one nocturnal awakening per week due to cough, wheeze or breathlessness with an average overnight fall in peak expiratory flow rate of at least 15% during a 2-week run-in period. 2. The lowest peak expiratory flow rate occurred at 02.00–04.00 hours in the group with nocturnal asthma, whose overnight fall in peak expiratory flow rate was 29 ± 5% in comparison with 5 ± 1% (means ± sem) in the normal subjects. 3. Plasma methylhistamine levels at night (0.200–04.00 hours) were lower than during the day (10.00–20.00 hours) in both asthmatic patients and normal subjects (asthmatic patients: day, median 0.22 ng/ml, 95% confidence intervals 0.18–0.34 ng/ml; night, 0.17 ng/ml, 0.13–0.24 ng/ml; P<0.01; normal subjects: day, 0.31 ng/ml, 0.24–0.41 ng/ml; night, 0.24 ng/ml, 0.21–0.33 ng/ml; P<0.01). 4. The serum eosinophil cationic protein level was higher by day (30 ng/ml, 8–47 ng/ml) than by night (21 ng/ml, 5–34 ng/ml; P<0.04) in the group with nocturnal asthma, but did not change significantly with the time of day in the normal subjects (day: 8 ng/ml, 4–14 ng/ml; night: 8 ng/ml, 5–21 ng/ml). 5. Peripheral blood eosinophil counts fell in the early morning in the patients with nocturnal asthma (day: 0.52 × 109/l, 0.14–0.76 × 109/l; night: 0.29 × 109/l, 0.13–0.57 × 109/l; P= 0.03), but did not change significantly in the normal subjects. 6. This study indicates that a rise in plasma histamine concentration is not a prerequisite for nocturnal asthma.

Venous Plasma Histamine in Exercise- and Hyperventilation Induced Asthma in Man

1981 ◽  
Vol 61 (2) ◽  
pp. 159-162 ◽  
Author(s):  
P. J. Barnes ◽  
M. J. Brown
Keyword(s):  
Mast Cell ◽  
Peak Expiratory Flow ◽  
Normal Subjects ◽  
Plasma Histamine ◽  
Radioenzymatic Assay ◽  
Expiratory Flow ◽  
Exercise Induced ◽  
Male Subjects ◽  
Venous Plasma

1. Venous plasma histamine was measured by a specific and sensitive radioenzymatic assay in seven male extrinsic asthmatic and six age-matched non-atopic non-asthmatic male subjects during exercise and voluntary isocapnic hyperventilation. 2. There was no change in peak expiratory flow in normal subjects with exercise or hyperventilation, but asthmatic subjects showed a 29.4 ± sem 5.8% fall after exercise and a 29.0 ± 5.4% fall after matched hyperventilation. 3. Plasma histamine was significantly higher (P < 0.05) in asthmatic (6.2 ± 0.95 nmol/l) than that in normal subjects (3.4 ± 0.61 mmol/l) and showed a significant (P < 0.01) rise (to 14.4 ± 1.83 nmol/l) during exercise in asthmatic, but not in normal subjects. This suggests that discharge of mast-cell mediators may occur during exercise in asthmatic subjects who develop exercise-induced asthma. 4. With hyperventilation there was no change in plasma histamine in either asthmatic or normal subjects, but this does not exclude the possibility that mediators may be released locally in the airways.

EFFECT OF BODY MASS INDEX ON PEAK EXPIRATORY FLOW RATE

2019 ◽  
Vol 3 (9) ◽  
Author(s):  
K. Subramanyam ◽  
Dr. P. Subhash Babu
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Peak Expiratory Flow ◽  
Flow Rate ◽  
Peak Expiratory Flow Rate ◽  
Normal Weight ◽  
The Body ◽  
Health Care Centre ◽  
Expiratory Flow ◽  
Group B

Obesity has become one of the major health issues in India. WHO defines obesity as “A condition with excessive fat accumulation in the body to the extent that the health and wellbeing are adversely affected”. Obesity results from a complex interaction of genetic, behavioral, environmental and socioeconomic factors causing an imbalance in energy production and expenditure. Peak expiratory flow rate is the maximum rate of airflow that can be generated during forced expiratory manoeuvre starting from total lung capacity. The simplicity of the method is its main advantage. It is measured by using a standard Wright Peak Flow Meter or mini Wright Meter. The aim of the study is to see the effect of body mass index on Peak Expiratory Flow Rate values in young adults. The place of a study was done tertiary health care centre, in India for the period of 6 months. Study was performed on 80 subjects age group 20 -30 years, categorised as normal weight BMI =18.5 -24.99 kg/m2 and overweight BMI =25-29.99 kg/m2. There were 40 normal weight BMI (Group A) and 40 over weight BMI (Group B). BMI affects PEFR. Increase in BMI decreases PEFR. Early identification of risk individuals prior to the onset of disease is imperative in our developing country. Keywords: BMI, PEFR.

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