Peak Expiratory Flow Can and Should Be Done at Home for Asthma Monitoring
Yes, PEF measurement is specifically designed for and most suitable for home monitoring in asthma patients, providing objective day-to-day assessment of airway obstruction for within-patient comparisons over time. 1
Why Home PEF Monitoring Is Recommended
PEF measurement is most suitable for ambulatory monitoring for within-patient comparisons over time, rather than as a clinic-measured parameter where it is inferior to FEV1. 1 The American Thoracic Society/European Respiratory Society explicitly states that home monitoring is the optimal use case for PEF in asthma management. 1
Key Benefits of Home PEF Monitoring
Early detection of exacerbations: Home lung function measurement helps detect deterioration and guide treatment changes, particularly in patients with refractory asthma who often have reduced perception of their airflow limitation. 1
Objective assessment: Provides an objective day-to-day measure of airway obstruction when patients and physicians are often unable to correctly estimate the degree of airway obstruction by clinical observation alone. 2
Improved outcomes: Management based on home PEFR measurements can result in fewer symptoms, fewer days absent from work or school, fewer emergency visits, fewer hospitalizations, lower requirements for rescue medications and oral corticosteroids, and better pulmonary function. 2
Captures variability: Sequential measures of PEF variability correlate with increased airway responsiveness, and diurnal variability >13% is an important diagnostic characteristic of asthma. 1, 3
Practical Implementation Requirements
Essential Technical Considerations
Adequate training is mandatory: Good within-session reproducibility can be achieved for home PEF monitoring with proper training, but technique should be checked at every clinic visit. 1
Use the same device: The same instrument should be used on each occasion if possible to ensure consistency. 1
Timing matters: Patients should record PEF before taking routine study medication and preferably before reliever medication. 1 Most studies use morning recordings either on arising or within a specified time-window. 1
Multiple measurements: Patients should complete symptom diaries before measuring PEF to avoid bias, and the highest value from three maneuvers is usually analyzed. 1
Important Caveats and Limitations
In children, home PEF monitoring has significant limitations: Even with careful training, approximately 50% of children aged 4-8 years cannot perform PEF maneuvers adequately. 4 Results from home spirometry in children are inconsistent even with careful training. 1
PEF monitoring adds little value in mild asthma: In young patients with milder asthma, PEF monitoring is too insensitive to register meaningful clinical changes and adds little to daily recording of symptoms and bronchodilator use. 5
Device accuracy varies: PEF meter readings correlate poorly with PEF measured by spirometry in the laboratory, highlighting the importance of using PEF for within-patient trends rather than absolute values. 5
Modern Alternatives and Innovations
Electronic devices with automatic data transmission show promising results, with high rates of successful recordings and parental satisfaction in feasibility studies. 3 Compact electronic devices now make daily home monitoring of FEV1 a realistic and successful alternative to PEF monitoring. 1
Clinical Decision-Making Framework
For adults with moderate-to-severe asthma: Implement home PEF monitoring as part of a comprehensive self-management program with clear action plans based on PEF zones. 2
For patients with refractory asthma: Aggressive home monitoring is specifically indicated, as these patients often demonstrate low perception of their functional status. 1
For children and mild asthma: Consider symptom-based monitoring instead, as PEF monitoring provides limited additional benefit and has technical challenges. 5, 4
Best practice requires: Coupling home PEFR monitoring with thorough asthma education and periodic office spirometry for optimal results. 2