Peak Expiratory Flow Readings Research Articles

ASTHMA IN DARLEY DALE: GP AUDIT

AbstractAsthma is a common illness in the United Kingdom and its incidence and severity has increased in recent years. In a paper published recently in the BMJ (1) I reported the results of a first audit cycle of asthma care in Darley Dale after starting an asthma clinic in the practice. I showed that, as a result of an audit exercise undertaken before the clinic was set up and after it had been in operation for one year, significant improvements in recording of data relevant to the management of patients with asthma was obtained – the term “asthma” entered in the patient's computerised summary record, smoking history and numbers of peak expiratory flow readings recorded. However, objective improvement in patients asthma – less requirement for oral steroids and salbutamol nebulisation – could not be demonstrated. There was an improvement in the ratio average:best peak flow rate in patients who had one or more measurements pre‐clinic and post‐clinic (81%→ 89%), but this difference was not statistically significant. A longer period of study will be required before major clinical improvement can be demonstrated.As a result of undertaking this audit exercise there has been renewed emphasis on prophylaxis of asthma for patients attending the clinic, greater effort made to see all patients with asthma for clinical review at least once annually, and to facilitate these activities a second clinic has been started.

THE INFLUENCE OF THE HELMET RESPIRATOR ON PEAK FLOW RATE IN ALUMINUM POTROOM

The efficiency of the Racal Airstream helmet respirator in improving peak expiratory flow rates (PEFR) and symptoms (dyspnea, wheezing, and cough) in aluminum potroom workers with respiratory complaints was assessed in 19 workers. Peak expiratory flow readings and symptom recording from a 2-week working period with use of the respirator were compared with a period when the 3M 9906 disposable mask was used. The study was designed as a randomized, parallel, cross-over study with five or six daily measurements of PEFR and daily symptom recording. A significant number of workers (15) had a higher mean peak flow in the helmet period than in the nonhelmet period (p less than 0.01); symptoms did not improve significantly in the helmet period. Objective evidence of respiratory protection was observed for the group of workers as a whole, but the effect on symptoms as well as individual effect on peak flow was minor in the majority of the workers.

Comparison of Incentive Spirometry and Intermittent Positive Pressure Breathing after Coronary Artery Bypass Graft

Fifty-two patients were randomized to receive either incentive spirometry (IS) or intermittent positive pressure breathing (IPPB) in addition to conventional chest physical therapy following coronary artery bypass grafting. Slow vital capacity and peak expiratory flow readings decreased rapidly and to an equal extent in both groups after surgery, and partly recovered by the sixth postoperative day (POP). Arterial PO2 values were similar for the groups on the first three POPs. On the POPs 2, 3, and 6, the number of chest films showing atelectases as well as the number of individual patients having atelectases revealed no statistically significant differences between the two groups. Based on the three variables studied, we consider both devices equal in efficiency after coronary surgery.

Persisting airway obstruction in asymptomatic children with asthma with normal peak expiratory flow rates

Twice-daily symptom scores and peak expiratory flow readings were compared with spirometric values (FEV 1 and forced expiratory flow rate between 25% and 75% of FVC [FEF 25–75]) measured at 2-week intervals in assessing airway obstruction in 20 children with asthma studied during 16 weeks. Of 56 2-week periods during which symptoms were absent, peak flow was decreased in 30 (54%), FEV 1 in 20 (36%), and FEF 25–75 in 37 periods (66%). Peak flow readings were normal in 13 of 70 periods (16%) in which FEV 1 was decreased, and in 33 of 113 periods (29%), in which FEF 25–75 was decreased. Of 25 periods in which symptoms were absent and peak flow was normal, 19 (76%) were associated with decreased FEF 25–75. The results confirm previous studies that indicate peak flow readings are a useful addition to symptom diaries. More importantly, they demonstrate that airway obstruction may be present in a large proportion of asymptomatic children with asthma who have normal peak flow rates and suggest that frequent assessment of FEF 25–75 is required, as well as daily monitoring of symptoms and peak flow both in trials of drug therapy and for more optimal assessment of the effectiveness of therapy in clinical practice.

Points: Falsely high peak expiratory flow readings

Points: Falsely high peak expiratory flow readings