Objective: The present study was undertaken to establish the effect of pollutants in the form of auto-exhaust, gases, etc. on the respiratory airways of healthy, non-smoking bus drivers in the age ...group of 20-55 years, by measuring the peak expiratory flow rate (PEFR) values. Materials and Methods: One hundred healthy, non-smoking bus drivers in the age group of 20 years to 55 years. were selected randomly from a bus stand of the PRTC (Punjab Roadways Transport Corporation) in the Patiala district and their PEFR values were compared with those of one hundred healthy, non-smoking persons in the age group of 20 years to 55 years, who were engaged in professions other than bus driving. Subjects with a prior history of reactive airways or bronchodilator intake were excluded. The influence of age, height, weight, body surface area and the duration of exposure on PEFR were studied. The PEFR test was performed by using Mini Wright’s Peak Flow Meter. Results: The mean PEFR of the bus drivers was found to be less than that of the control subjects in each group and the results were found to be statistically highly significant (p<0.005). This decrease in the PEFR in the bus drivers was probably due to their continuous occupational exposure to pollutants, which may have caused an adverse effect on their respiratory functions. Conclusion: There was a significant decrease in the lung functions of the bus drivers, as compared to those of the controls.
SETTING: Nine selected out-patient clinics caring for asthma patients in Algeria, Guinea, Ivory Coast, Kenya, Mali, Morocco, Syria, Turkey and Vietnam.DESIGN: Prospective enrolment of consecutive ...patients considered by the practitioner to have asthma with evaluation of adherence
of the practitioner with recommended standard case management, including proportion of patients confirmed to have asthma, proportion in whom severity was correctly graded and proportion in whom treatment with inhaled corticosteroids corresponded to severity grade.RESULTS: Of 499 consecutive
patients, 456 (91%) were enrolled and evaluated. The diagnosis was confirmed in 263 (58%). Agreement between the practitioner and the guidelines in assigning grade of severity was moderate overall (kappa = 0.42). It was higher for assignment of grade using symptoms (κ = 0.51),
but poor for assignment of grade using peak expiratory flow (PEF) rate (κ = 0.29), with practitioners tending to underestimate the severity. Agreement between the practitioners' assessment of severity and treatment with inhaled corticosteroids was poor (κ = 0.18),
with underutilisation of inhaled corticosteroids.CONCLUSIONS: Practitioners caring for asthma patients in this study tended to underutilise the PEF rate in assessing their patients and underutilised treatment of patients with inhaled corticosteroids.
To test a system with milk flow-controlled pulsation, milk flow was recorded in 29 Holstein cows during machine milking. The three different treatments were routine milking (including a ...pre-stimulation of 50–70 s), milking with a minimum of teat preparation and milking with milk flow-controlled b-phase, i.e. with a gradually elongated b-phase of the pulsation cycle with increasing milk flow rate and shortening again during decreasing milk flow. For data evaluation the herd was divided into three groups based on the peak flow rate at routine milking (group 1: <3·2 kg/min; group 2: 3·2–4·5 kg/min; group 3: >4·5 kg/min). Compared with routine milking, milking with milk flow-controlled b-phase caused a significant elevation of the peak flow rate and the duration of incline lasted longer especially in cows with a peak flow rate of >3·2 kg/min in routine milking. In milking with a minimum of teat preparation the duration of incline lasted longer compared with the two other treatments. Bimodality of milk flow, i.e. delayed milk ejection at the start of milking, was most frequent at milking with a minimum of teat preparation. No significant differences between routine milking and milking with milk flow-controlled b-phase were detected for all other milking characteristics. In summary, milking with milk flow-controlled b-phase changes the course of milk removal, however mainly in cows with high peak flow rates.
Objective: Continuous nebulization is becoming more popular in the management of acute bronchospasm in the emergency department (ED). Controversy still exists as to the optimal dose of albuterol for ...such exacerbations. The present study hypothesis was that there is no difference between continuous nebulization of albuterol at 7.5 mg/hr (usual dose) and 15 mg/hr (high dose) in peak flow improvement up to three hours. Methods: This was a randomized, controlled, double‐blind trial, set in an urban county teaching ED. One hundred twenty‐seven patients with acute bronchospasm and an initial peak flow (PF) less than 75% predicted were enrolled. Patients were randomized to usual‐dose (UD) or high‐dose (HD) groups along with a standard treatment protocol. Primary end‐points were analyzed using repeated‐measures analysis of variance (ANOVA), and 95% confidence intervals (95% CIs) are given for such variables. Results: Sixty‐seven patients were randomized to the HD albuterol group, and 63 completed the study. Sixty patients were randomized to the UD group, and 55 completed the study. Repeated‐measures ANOVA found no difference in systolic blood pressure, diastolic blood pressure, pulse, respiratory rate, Borg dyspnea scale score, and peak flow over time between the groups. The mean (±SD) peak flow improvement at one hour was UD 51 (±49) L/min vs. HD 45 (±50) L/min, mean difference 6.8 L/min (95% CI = ‐11 to 24.9 L/min). Adjusting for baseline, the percentage increase in peak flow at one hour was UD 44% (±60%) vs. HD 30% (±40%), mean difference 14% (95% CI = ‐4.4% to 32.4%). Time to disposition showed a mean of 188 (±129) minutes for UD and 230 (±183) minutes for HD, mean difference 42 minutes (95% CI = ‐170 to 101 min). One patient in the HD group was intubated. Admission rate was UD 70.9% vs. HD 65%, mean difference 5.9% (95% CI = ‐10.9% to 22.7%). Conclusions: In treating acute, moderately‐severe bronchospastic ED patients with peak flow less than 75% of predicted with albuterol by continuous nebulization, 15 mg/hr appears to offer no advantage over 7.5 mg/hr in peak flow improvement or length of stay in the ED.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Aims To investigate the poorly understood relationship between work-related respiratory symptoms, airway reactivity, across working shift change in forced expiratory volume in 1 s (FEV1) and ...work-related changes in serial peak expiratory flow (sPEF) measures in a group of textile workers. Methods Fifty-three workers, 34 exposed to cotton dust and 19 to man-made fibre (MMF), were investigated using a standard respiratory questionnaire, sPEF, across-shift FEV1 measurement and airway responsiveness. Results Thirty-four workers (64%) were male, and 9 workers (17%) had a >5% across-shift fall in FEV1, and these falls were associated with the presence of work-related symptoms. Seven workers had a positive sPEF chart as judged by the software analysis (OASYS), although there was no relationship between work-related symptoms and sPEF. Six cotton workers (18%) and one MMF worker (5%) had airway hyperreactivity, which was associated strongly with work-related symptoms. Five of the 7 subjects with a positive sPEF had airway hyperreactivity compared with 12 of 46 with a negative sPEF. Conclusions In this worker group, the presence of work-related respiratory symptoms was best associated with airway hyperresponsiveness and across-shift changes in FEV1. While a positive sPEF chart was associated with increased airway responsiveness, it was not associated with work-related symptoms. sPEF measurements may not be the initial investigation of choice for such workers. As these findings also have relevance to developing evidence-based approaches to health surveillance, further work is needed to better define these relationships in other workers complaining of work-related respiratory symptoms.
In this study, we examine the effect of exercise on the time and flow characteristics of the respiratory cycle profile at the point of volitional exercise termination. Eight males (mean age 29 years, ...s = 10; body mass 74 kg, s = 7; height 1.75 m, s = 0.04) undertook a cycle test to volitional exhaustion on a cycle ergometer, which allowed peak oxygen uptake (VdotO
2peak
) to be measured (mean 51 ml · kg
−1
· min
−1
, s = 7). At a later date, two sub-maximal tests to volitional exhaustion were completed in a random order at 76% (s = 6) and 86%VdotO
2peak
(s = 7). As expected, the magnitude of the respiratory flow and time characteristics varied with the three exercise intensities, as did the point of exercise termination and terminal ventilation rates, which varied from 7 to 27 min and 112 to 132 litres · min
−1
respectively. More importantly, however, at exercise termination some of the characteristics were similar, particularly the breathing frequency (at termination 49 breaths · min
−1
), the ratio between inspiration and total breath time (0.5), and the later occurrence of peak inspiratory flow (0.24 - 0.48 s). The coincident unity of these time and flow profile characteristics at exercise termination illustrates how the integration of timing and flow during breathing influence exercise capacity in non-elite athletes.
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BFBNIB, FSPLJ, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Simulations provide an opportunity to examine how single or multiple perturbations may impact a specific species. The objectives of this study were to identify thresholds at which changes in stream ...peak flow, stream base flow, and/or chytrid fungus presence alter long-term
Rana chiricahuensis populations. We used scenarios with varying peak flow mortality rates, base flow mortality rates, and chytrid fungus mortality rates. Sensitivity analysis was also conducted. Over 50 years, populations in six scenarios increased and 13 scenarios decreased. Eight scenarios resulting with fewer than 100 individuals included stochastic effects for at least two of three perturbations and the remaining scenarios included chronic effects of 30% or higher. Scenarios with population increases had either no chytrid fungus effect or chronic effects from perturbations totaling less than 30%. In the absence of chytrid fungus, populations increased and became stable. At a 10% annual death rate caused by chytrid fungus, the
R. chiricahuensis population decreased 46.8%. At a 20% death rate, the population decreased 98.6%. Model scenarios were sensitive to peak flow death rates. As peak flow mortality increased to 10 and 20%, extinction rates increased to 91.7 and 99.9%, respectively. With model parameters and the no base flow mortality,
R. chiricahuensis populations declined by 92% with a 3.2% extinction rate at 50 years. Models with base flow mortality rates of 10 and 20% resulted in population extinction rates of 48.7 and 96.1%, respectively. Scenario analysis of perturbations on a hypothetical
R. chiricahuensis population provided a framework in which to view combined effects on a species. Analysis supports supposition that chytrid fungus is the proximate cause of many amphibian declines, but the added effect of base flow and peak flow has the potential to hasten declines.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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