Mini Peak Flow Meter Research Articles

Effect of Cigarette Smoking on Peak Expiratory Flow Rate

Introduction: Cigarette smoking is an intractable public health problem that carries a threat to the health of the entire population. Smoking is a known risk factor for chronic obstructive pulmonary diseases, cardiovascular diseases, certain cancers especially lung cancer.
 Objectives:To assess the effect of cigarette smoking on peak expiratory flow rate (PEFR) among cigarette smokers and examine whether PEFR differs between cigarette smokers and non-smokers.
 Materials and Methods: This is cross-sectional comparative study was done for one year from July 2014 to June 2015. A total of 150 subjects were recruited from the medicine and allied outpatient departments of Mymensingh Medical College Hospital and Mymensingh locality. They are divided into 50 non-smokers (Group I) and 100 smokers (group II) with a duration of smoking 5-10 years (group IIA) and more than 10 years (Group IIB). PEFR was recorded by using Wright’s mini Peak flow meter. A questionnaire including demographic data was completed in all cases. The data were collected and analyzed using SPSS version 11.5.
 Results: Mean PEFR among non-smokers was 449.20±6.83 L/min whereas among smokers of 5-10 years duration(Group IIA) and above 10 years duration (Group IIB), it was 301.20±2.17 L/min and 297.80±2.54 L/min respectively. Mean PEFR values were significantly lower in smokers than non-smokers of both groups.
 Conclusion: Cigarette smoking has deleterious effects on lung function causing a significant reduction of PEFR in smokers compared to nonsmokers. Coordinated national strategies for tobacco prevention, cessation, and control are essential for the establishment of a smoke-free environment.
 JAFMC Bangladesh. Vol 15, No 2 (December) 2019: 165-167

ASSESSING THE IMPACT ON PEFR AMONG SMOKERS AND PASSIVE SMOKERS–A COMPARATIVE STUDY

Objective: The purpose of this study was to monitor the intensity and difference in Peak Expiratory Flow Rate (PEFR) between smokers and passive smokers.
 Methods: A total of 1000 participants were enrolled in two groups as smokers and passive smokers who are living closely with smokers. Their PEFR values were measured with Wright’s mini peak flow meter. The influence of smoking on the lung function among smokers and passive smokers were assessed with a suitable statistical test.
 Results: Among the study participants, most of the smokers were in the age group of 31 to 60 and 31 to 50 in passive smokers. Based on the lung function smokers (31%) and passive smokers (19.2%) were in the red zone, PEFR was decreased in both smokers as well as passive smokers, and the magnitude of decline was higher in passive smoking elderly individuals. The impact of passive smoking was significantly observed in all the categories of smoking history they are living with.
 Conclusion: Smokers and passive smokers have equally deleterious effects on PEFR. Where passive smoking emerged as the main variable to influence airway obstruction in smokers that caused a greater reduction in PEFR.

Peak expiratory flow among healthy children aged 5-14 years in China.

Guidelines of the Global Initiative for Asthma recommend the use of peak expiratory flow (PEF) in the assessment and management of patients with asthma. However, normal PEF values for Chinese children have not been thoroughly investigated. This was a cross-sectional study of 3,169 healthy children aged 5-14 years from research centers in five cities of China: Guangzhou, Suzhou, Chengdu, Xi'an, and Beijing. We established pediatric reference values for PEF using a mini peak flow meter. PEF values recorded by the mini peak flow meter were compared with those obtained using a spirometer. Height was the biometric variable with greatest correlation to PEF for both sexes. Significant differences were noted between males and females. The regression equation for boys was calculated as PEF =4.39× height (cm) -300.48 (R2 =0.76, P<0.001); for girls, this equation was PEF =4.13× height (cm) -278.04 (R2 =0.72, P<0.001). PEF values for Chinese children according to age were close to those of Irish, Turkish, and British children but were lower than those of children in Greece; PEF values according to height were similar to those of Turkish and Danish children but lower than values for children in Ireland. We established normal PEF values and developed predictive equations using linear regression analysis for Chinese children aged 5-14 years, while Greece and Ireland references were inappropriate for Chinese children.

Prevalence of chronic respiratory disorders in a rural area of North West India: A population-based study.

Introduction:Chronic respiratory diseases are an important cause of disability across the globe. The global burden of these diseases is showing a discernible upward trend. It is estimated that 500 million people suffer from them.Materials and Methods:The study was conducted with the aim to estimate the prevalence of chronic obstructive pulmonary disease (COPD) in a rural Indian population. For this, a population-based survey was conducted using modified British Medical Research Council questionnaire. This was followed by subjecting the respondents to Wright's mini peak flow meter to find out the peak expiratory flow rate to diagnose the COPD cases.Results:The prevalence of chronic bronchitis, bronchial asthma, and COPD was found to be 3.36%, 1.18%, and 4.21%, respectively.Conclusions:Chronic respiratory disorders are more prevalent among rural adults hinting to a rural-urban divide. Therefore, the focus of preventive strategies should take into account this difference.

Respiratory function of workers at a construction company in Bangalore Urban district

Introduction: Construction sector is one among the largest employers in India. Most of the construction workers are migrants susceptible to occupational health hazards. Construction workers are exposed to a variety of dust and chemicals that may pose a risk to the respiratory system. There is paucity of data on the respiratory function of construction workers in India. Objectives: The objectives were to assess the respiratory function of construction workers and to study possible factors associated with the respiratory function of these construction workers. Methodology: A cross sectional study was conducted among 197 workers in a construction company in Bangalore Urban district from November - December 2010. The study tools were an interview schedule to study the respiratory function and possible associated factors and clinical examination which included anthropometry (height, weight) and Wright’s mini peak flow meter to measure peak expiratory flow rate (PEFR). The data was analyzed using standard statistical software. Results: Among male workers, the mean PEFR was 457.43 l/min (SD 65.38 l/min) while among female workers, the mean PEFR was 326 l/min (SD 46.95 l/min). Respiratory function as measured by peak flow meter was decreased in 127 (64.5%) workers. The current reported tobacco smoking was 41.2% (77) among 187 males. Only 3 (1.5%) workers reported to use of face mask. There was no significant association (p&gt;0.05) between respiratory function, and duration of work more than a year at construction company, use of face mask or smoking. Conclusion: This preliminary study revealed that the respiratory function among the workers was decreased. More precise studies with population control matched for age using pulmonary function tests are needed to assess the findings of the study.DOI: http://dx.doi.org/10.3126/ijosh.v4i1.10000

Effect of cigarette and cigar smoking on peak expiratory flow rate.

Tobacco smoking in India has been increasing alarmingly. Smoking is a known risk factor for chronic obstructive pulmonary disease (COPD), cardiovascular diseases and certain cancers, especially, the lung cancer. The percentage prevalence of cigarette smoking (18.5%) and cigar smoking (4%) in males is high in Andhra Pradesh compared to other southern states. There is not enough scientific literature to correlate about intensity of cigarette and cigar smoking and their impact on lung function though high prevalence is reported in Andhra Pradesh, India. The purpose of this study was to examine whether PEFR differs between cigarette and cigar smokers compared to non-smokers and also to estimate the intensity of cigarette and cigar smoking on PEFR. PEFR was recorded in cigarette smokers (n=49) and cigar smokers (n=10) as well as in non-smokers (n=64) using Wright's mini Peak Flow Meter. PEFR is decreased in both cigarette as well in cigar smokers compared to non-smokers and the magnitude of decline was higher in cigar smoking elderly individuals. The intensity of cigarette and cigar smoking (pack-years) emerged as the main variable to influence airway obstruction in smokers that caused greater reduction in PEFR.

Peak Expiratory Flow Rate In Healthy Rural School Going Children (5-16 Years) of Bellur Region For Construction of Nomogram

Peak Expiratory Flow Rate (PEFR) recording is an essential measure in the management and evaluation of asthmatic children.It is helpful in monitoring disease progression and response to treatment. The PEFR can be measured by a simple instrument-peak expiratory flow meter. To construct nomogram of PEFR in healthy rural school going children from Mandya district of Karnataka state, India and to use these nomograms for comparison with that of children with obstructive lung diseases for this region. The study was conducted on Healthy rural school going children, both boys and girls between the age group of 5-16 years. For the determination of PEFR we used Mini Wright Peak Flow Meter. At three time measurement, the highest value of PEFR was recorded. Formula for prediction of PEFR was estimated by linear regression analysis after the correlation of PEFR with age and height for both boys and girls. PEFR was measured in 1028 children aged 5 to 16 years by using Wright's mini peak flow meter. Prediction equations were derived for PEFR with height in boys and girls. Normograms were plotted based on the observed values of PEFR in the study population. Significant linear correlation was seen of PEFR with height in boys (p<0.001, r=0.7624) and in girls (p<0.001, r=0.8825). Prediction equation for PEFR are -317.43 + 4.40 x height (cm) in boys and - 321.21 + 4.25 x height (cm) in girls. Reference values of PEFR are affected by regional, environmental and anthropometric factors. Hence, it is necessary to have regional reference values for children. Among different factors affecting PEFR, height correlates better with PEFR than weight and sex. Hence nomograms constructed can be used for this region.

Exercise induced bronchial lability: A comparison between normal men and women.

The difference of bronchial lability that is bronchial hyper-reactivity between normal men and women is studied by standard exercise using Harvard steps. Preclinical medical students (M=30, F=30) with mean age of 18.64 years were assessed. Students included were nonsmokers & with no personal history of allergy or any respiratory disease. Parameters compared were age, sex, height, weight & PFTs. Parameters i.e. PFTs were recorded before, during & upto 45 minutes after exercise with computerized spirometer & for PEFR Wright's Mini Peak flow meter was used. Exercise lability index (ELI), ELI % rise & % fall calculated. Resting FVC, FEV1, FEF25-75% & PEFR in men were significantly higher (p 0.05) but there was greater ELI % rise in PEFR values in women during exercise & lesser decline after it.. Women have a greater increase and lesser decrease in flow rates & showed earlier recovery as compared to men. This respiratory response pattern could account for the lower incidence, morbidity & mortality from respiratory allergic diseases seen in women.

Respiratory Evidence for Health Risks from Inhaled Car Exhaust in Traffic Policemen in Khartoum State

The objective: of this study is to evaluate the effect of exposure to car emission on respiratory parameters in traffic policemen working in Khartoum state (Khartoum South, Khartoum North and Omdurman) during the period from 21 March to 15 may 2002. Methods: A case-control study with a total of 175 male traffic policemen who have volunteered to participate in the study was conducted. They were divided into four groups according to the state of exposure to car exhaust. Traffic policemen who were not exposed to car exhaust and not smokers were taken as controls, and exposed non-smokers were considered as study group. Questionnaire was distributed to collect relevant information from participants. Standard anthropometric instruments were used for weight and height. Microspirometer and mini peak flowmeter were used to measure FEV1, PEFR and FVC. Results: Out of the 175 participants 90 were exposed to car exhaust; of these 55 were not smokers. The anthropometric parameters in the study group (exposed non-smokers) were similar to the control group. The lung function tests were not different from the control. Concerning exposure to car exhaust there was insignificant negative correlation between the duration of exposure and PEFR, FEV1and the FEV1/FVC ratio. There were no differences between the control and other group in lung functions so that chronic exposure to car exaust has no significant effect on lung functions in Sudan.

PM10 EXPOSURE FROM COOKING FUELS AND IMPACT ON WOMEN AND CHILDREN: EXPERIENCE FROM SOUTHWEST NIGERIA

ISEE-440 Introduction: This paper describes the concentration of particulate matter (10μm) in smoke generated from different fuels - firewood, kerosene, charcoal and gas - used by communities, and the health impacts on women and children. Methods: The study was located in Ibadan, capital of Oyo State, with a population of over 3.5 million. Five Local Government Areas of the inner Ibadan metropolis were involved in the study. The communities were selected from three strata - high, medium and low density areas - based on population density and socio-economic status. Stratified random sampling was employed to select four communities from each stratum, based on the type of fuel being used. Ekotedo and Agbeni were selected to represent high density areas, Agbowo represented the medium density area, and Old Bodija represented the low density area. The eligible population for the purpose of the study comprised every mother aged 16 years and above and children younger than 5 years of age, who were permanent residents in the identified areas. In all, 186 households were monitored for PM10, while 130 mother-child pairs were interviewed and monitored for exposure effects. A structured questionnaire was administered to the mothers to gather information on demographic characteristics and the fuel types used. Focus group discussions and air monitoring were also conducted. Results: PM10 concentration was measured thrice in each household for over 5 minutes. Measurement was done when the fire was ignited and started burning. Readings from the three measurements were pooled and computed. The daily exposure to respirable particulate matter, PM10was estimated using a Haz-dust particulate monitor. The instrument was calibrated with test-dust, and the particle size was from 0.1–50 μm, as recommended by the US Environmental Protection Agency (EPA) PM10 criteria and thoracic region for airborne particles, as defined by the ACGIH (American Conference of Government Industrial Hygienists) and the NIOSH (National Institute of Occupational Safety and Health). Lung function of the subjects was determined using a mini peak flow meter (Aimed Clement Clarke International London, U.K.). Peak expiratory flow rate was measured in the respondents before and after cooking. The results indicated that 37.7% of the respondents used firewood, 33.1% used kerosene, 17.7% used charcoal and 11.5% used gas. Firewood users spend more time in the cooking process and stay close to the fire for longer periods of time, when compared to subjects who use other fuels. Smoke released from these fuel sources contained particulate matter up to a maximum level of 9,500 μg/m3. Charcoal users had the lowest lung function values, as compared to users of other fuels. The health effects among the respondents included difficulty in breathing, runny nose, sneezing, chest pain, chest tightness, cough, watery eyes, eye redness, irritation of the nose and throat, sweating and headache. The type of kitchen used and the place of cooking also have an impact on the health effects seen.

Further studies on the clinical efficacy of Solanum xanthocarpum and Solanum trilobatum in bronchial asthma

The clinical efficacy of two herbs S. xanthocarpum and S. trilobatum in a dose of 300 mg tds for 3 days was investigated in mild to moderate bronchial asthma. Their effect was compared with standard bronchodilator drugs, salbutamol (4 mg) and deriphylline (200 mg). The respiratory function was assessed by measuring the peak expiratory flow rate (PEFR) using a mini peak flow meter. In addition, improvement in lung function was assessed by physical examination (rhonchi and crepitation) and other symptoms such as cough, breathlessness and sputum. S. xanthocarpum and S. trilobatum produced a progressive improvement in the ventilatory function of asthmatic individuals over 3 days. The scores for rhonchi, cough, breathlessness and sputum were decreased by these drug treatments. The improvement in PEFR and the reduction in other symptom scores clearly indicate a bronchodilator effect, a decrease of oedema and secretions in the airway lumen. The response to these herbs can be considered to be equivalent to that of deriphylline but less than salbutamol. No untoward effects were reported during the study. The present study further confirms the traditional use of these herbs in bronchial asthma.

Peak expiratory flow at increased barometric pressure: comparison of peak flow meters and volumetric spirometer

Increasing numbers of patients are receiving hyperbaric oxygen therapy as an intensive care treatment, some of whom have pre-existing airway obstruction. Spirometers are the ideal instruments for measuring airway obstruction, but peak flow meters are useful and versatile devices. The behaviour of both types of device was therefore studied in a hyperbaric unit under conditions of increased pressure. It is important to have a non-electrical indicator of airway obstruction, to minimize the fire risk in the hyperoxic environment. The hypothesis was tested that, assuming that dynamic resistance is unchanged, both the Wright's standard and mini-peak flow meters would over-read peak expiratory flow (PEF) under increased pressure when compared with a volumetric spirometer, as the latter is unaffected by air density. It was postulated that a correction factor could be derived so that PEF meters could be used in this setting. Seven normal subjects performed volume-dependent spirometry to derive PEF, and manoeuvres using both standard and mini PEF meters at sea level, under hyperbaric conditions at 303, 253 and 152 kPa (3, 2.5 and 1.5 atmospheres respectively; 1 atmosphere absolute=101.08 kPa), and again at sea level. There was a progressive and significant decline in PEF with increasing pressure as measured by the spirometer (69.46+/-0.8% baseline at 303 kPa compared with 101 kPa), while the PEF meters showed a progressive increase in their readings (an increase of 7.86+/-1.69% at 303 kPa with the mini PEF meter). Using these data points, a correction factor was derived which allows appropriate values to be calculated from the Wright's meter readings under these conditions.

Accuracy of peak flow meters Don't interchange devices

EDITOR, - Peter D Sly and colleagues' paper highlights a common mistake in the management of asthma - namely, interchanging devices measuring peak flow.1 In 1990 colleagues and I designed a small study (unpublished) to investigate possible discrepancies between readings obtained with Wright mini peak flow meters and standard Wright peak flow meters. It was undertaken because of the lack of consensus in the literature regarding the comparability of the two devices and after a suggestion that regression analyses commonly used in previous research were inappropriate for comparing the results of two measurement techniques. In addition, earlier comparisons had looked primarily at flow ranges appropriate to adults. Peak flows were recorded from 186 children, who used both devices. In the laboratory 61 Wright mini peak flow meters were calibrated against known flows with a spirometer. Limits of agreement were then calculated for clinical and laboratory data and showed that the two devices may differ by more than 100 litres/min. The greatest percentage discrepancy occurred at lower flow rates, when the Wright mini peak flow meter tended to read higher flow values than the standard Wright peak flow meter. As the two meters do not give comparable peak flow measurements …

Treat mini peak flow readings with caution.

Mini peak flow meters may not accurately track clinically important changes in the lung function of children with asthma, researchers say.

Accuracy of mini peak flow meters in indicating changes in lung function in children with asthma

To assess whether mini flow meters used to measure peak expiratory flow can track changes in lung function and indicate clinically important changes. Comparison of measurements with a spirometer and different brands of mini flow meter; the meters were allocated to subjects haphazardly. 12 boys with asthma aged 11 to 17 attending boarding school. Peak expiratory flow measured twice daily for three months with a spirometer and at least one of four brands of mini flow meter. The relation between changes in lung function measured with the spirometer and those measured with the mini flow meters was generally poor. In all, 26 episodes (range 1-3 in an individual child) of clinically important deterioration in lung function were detected from the records obtained with the spirometer. One mini flow meter detected six of 19 episodes, one detected six of 15, one detected six of 18, and one detected three of 21. Not only are the absolute values of peak expiratory flow obtained with mini flow meters inaccurate but the clinical message may also be incorrect. These findings do not imply that home monitoring of peak expiratory flow has no place in the management of childhood asthma but that the values obtained should be interpreted cautiously.

Can a newβ 2-agonist reduce the mortality of asthma?

Tulobuterol is a synthetic beta-adrenergic agonist which, when administered orally, is a potent, long-acting bronchodilator. The safety and efficacy of 2 mg tulobuterol tablets taken twice daily was compared to that of 4 mg salbutamol tablets taken three times daily for a period of 12 weeks in outpatients with stable chronic asthma in a randomized, double-blind, multi-center study conducted in Australia. Strict entry criteria were employed; only those patients whose baseline FEV1 value was between 40-70% of the predicted normal value and increased at least 20% after two inhalations of a metered dose (250 micrograms per dose) of terbutaline aerosol at a screening visit were included. Treatment with active study drug was preceded by a 2 week single-blind, placebo lead-in period. The onset and duration of the bronchodilating effect was studied on the first day of the placebo lead-in period and on the first and last days of the 12 week parallel design treatment period. Of 140 patients enrolled, 73 had tulobuterol and 67 had salbutamol. Of these, 61 tulobuterol and 59 salbutamol treated patients could be evaluated for efficacy. Of the 140 patients, 129 completed the study. All patients were issued a mini peak flow meter and diary cards to record daily PEFRs and symptoms of airways obstruction throughout the study. The demographics of the patients in both treatment groups were similar in all modalities: they were comparable in age, duration of asthma, mean FEV1 (expressed as percent of predicted normal), and reversibility (as demonstrated by an increase in FEV1 after administration of a beta 2-agonist aerosol).(ABSTRACT TRUNCATED AT 250 WORDS)

THE MEASUREMENT OF RESPIRATORY FUNCTION IN ATHMATIC CHILDREN ON SUMMER CAMP USING A MINI PEAK FLOW METER

Of 65 asthmatic children, we measured the respiratory function 3 times per day using a mini peak flow meter during a summer camp. And then, we investigated the exercise load of daily life in asthmatic children. We divided the group of 65 children into 4 classes by % PEFR changing pattern for 6 days.I-a group; all time up from 100%I-b group; all time up from 70%II group; one time down from 70%III group; more Chas two times down from 70%At awaking, the mean % PEFR of I-a group was highest and I-b, II group were higher than III group, and at noon and going to bed, the mean % PEFR of I-a group was higher than the other 3 groups. For the investigation of the exercise load, we calculated % PEFR ratio before and after swimming and hiking On swimming, the % PEFR ratio of II, III group was higher than I-a, I-b group. On hiking, the % PEFR ratio of II group was lower, and III group was higher than I-a, I-b group. For analysis of the data, we added the data of % PEFR before lunch time. And investigated the % PEFR ratio of the first period and second period. Of I-a group, the difference of both ratios was not recognised, but of other 3 groups, the % PEFR ratio of the second period wan lower than first period.This may have been due to the decline of exercise preliminary power.

Fungal contamination of mini peak flow meters

Sixteen peak expiratory flow meters from the Outpatient Department of Solihull Hospital were dismantled for inspection and washing. Fungal contamination was found in all 16 machines with visible contamination in four.

Respiratory muscle training in Duchenne muscular dystrophy.

Twenty two boys with Duchenne muscular dystrophy were entered into a randomised double blind crossover trial to compare respiratory muscle training with a Triflow II inspirometer and 'placebo' training with a mini peak flow meter. Supine posture was associated with significantly impaired lung function, but respiratory muscle training showed no benefit.

Comparison of The Performance of Two Mini Peak Flow Meters

Two mini peak flow meters commonly used to monitorize the peak expiratory flow rate (PEFR) are compared to assess their agreement, precision and, with respect to a standard pneumotachygraph, accuracy. Precision of the mini-Wright peak flow meter is greater, possibly as result of a systematic overestimation of PEFR values. The Assess peak-flow meter is more accurate, but its ability to reproduce the actual well-known PEFR variability is dependent from the absolute level of air flow. The agreement between two instruments is very poor, both in asthmatics and in normals, so that it is mandatory to use always the same mini peak flow meter in population studies and during the follow-up of asthmatic patients.