Peak flow measurement, also known as peak expiratory flow (PEF), is a straightforward way to evaluate the maximum flow rate that a student can achieve while forcefully exhaling after taking a full breath. Measured using a portable, hand-held device or peak flow meter, these readings can be helpful in early identification of worsening respiratory status, as well as in determining the efficacy of asthma treatment and when emergency care might be required. But, measuring peak flow is dependent on both the effort put in and the technique used, which can result in readings that are not always reliable or accurate. But, when combined with skilled symptom assessment and used in conjunction with a student's Asthma Action Plan, it is a tool that can provide school nurses the opportunity to enhance their management of asthma in the school setting.
The Significance of Peak Flow Data
Data collected from peak flow monitoring can serve multiple purposes. Primarily, it allows for the personalized management of a student's asthma by establishing their individual peak flow zones. The zones most typically used in asthma action plans are:
Green Zone: 80-100% of the personal best or "normal" peak flow rate indicates air is flowing well through central airways and asthma is well-controlled.
Yellow Zone: 50-79% of the personal best or "normal" peak flow rate, signaling caution and possibly the need for preventive medication due to narrowing airways.
Red Zone: Less than 50% of the personal best or "normal" peak flow rate; this medical alert denotes severe narrowing of the airways, requiring immediate action.
When an asthma action plan includes orders for peak flow monitoring, it equips school nurses with the capability to swiftly identify which zone a student falls into at any given time and enables the implementation of predetermined management strategies tailored to the severity of the situation. In some cases, changes in peak flow readings can detect modifications in the airways before any symptoms become noticeable.
School Considerations for Peak Flow Monitoring
Implementing peak flow monitoring in schools necessitates careful planning and consideration of several factors to ensure safety and efficacy.
Understanding: While peak flow monitoring can be used on children as young as four or five, student's cooperation with the proper technique may be restricted during acute exacerbations, and results must be interpreted accordingly, with caution. According to the AAP, "Symptoms are as important, probably even more important, than a peak reading."
Accessibility: Students with IHPs or Asthma Action Plans that include peak flow monitoring orders should provide the school nurse with a peak flow monitor. Peak flows can vary depending on the meter used, so students should use the same type/brand they have at home. Some schools stock peak flow meters with interchangeable mouthpieces.
Documentation: Detailed record-keeping is vital for tracking peak flow readings done at school and used as part of an asthma exacerbation assessment.
Collaboration: Finally, establishing a solid partnership between the school, parents, and the student's healthcare provider is essential for coordinated care. Regular communication can help adjust action plans as needed and ensure that everyone involved knows the student's asthma management status.
Peak flow meters are simple yet effective tools that offer a unique window into a student's respiratory well-being, enabling timely interventions and personalized care. It's essential to recognize its limitations and the need for accurate technique and effort, but when integrated thoughtfully into Asthma Action Plans and coupled with proactive communication and documentation, peak flow monitoring can significantly elevate the quality of asthma management in the school setting.
