Boggs P B, Hayati F, Washburne W F, Wheeler D A
Asthma 2000 Group, Shreveport, LA, USA.
Jt Comm J Qual Improv. 1999 Apr;25(4):163-81. doi: 10.1016/s1070-3241(16)30436-9.
Home monitoring of lung function using simple, inexpensive tools to measure peak expiratory flow rate (PEFR) has been possible since the 1970s. Yet although current national and international guidelines recommend monitoring of PEFRs via traditional run charts, their use by both patients and physicians remains low. The role of statistical process control (SPC) theory and charts in the serial monitoring of lung function at home were explored and applied to the direct care of patients with asthma. The method represents an integration of collective professional and improvement knowledge with the related disciplines of continual improvement, SPC, system thinking/system dynamics, paradigms, and the learning community/organization.
Use of PEFR control charts for four patients cared for at the Asthma-Allergy Clinic and Research Center (Shreveport, La) is described. The key to good asthma control is the ability to optimize lung function by reducing the variation between serial lung function measurements and thereby generate a safe range of function. Knowledge of the type of variation (special cause or common cause) in the system helps in focusing clinical decision making. Case 4, an 11-year-old boy, for example, shows how control charts were used to learn the effects of a new inhaled corticosteroid. Comparison of the last 14 days of baseline and the last 14 days of open label use of the inhaled corticosteroid showed an obvious improvement in actual PEFR values--which a run chart or comparison of means would have easily demonstrated. The control chart showed that this child's care process at baseline was functionally at risk for severe asthma (46% personal best) and that the effect of the new medication not only elevated the mean function but shifted the range of function from 46%-72% personal best to 78%-102% personal best. At this new range of function the patient's system of care was not capable of delivering values that are at risk for severe asthma. Unless the range of function the change in care is capable of producing is specifically quantitated, misinterpretation of improvement data can occur.
Developing the concept of the PEFR control chart involved examining and challenging traditional mental models for monitoring PEFR at home in the care of asthma, acquiring a better understanding of the workings of dynamic systems and with system thinking, and sharing what was learned with patients and seeking their input.
The PEFR control chart employs an interesting statistical platform that enables the integration of knowledge of serial measurements and knowledge of the variation between those measurements into a tool with which to better assess the asthma care process being followed. This tool provides clinical insights, practical knowledge, and opportunities unavailable to patients and physicians via traditional PEFR charting.
自20世纪70年代以来，使用简单、廉价的工具在家中监测肺功能以测量呼气峰值流速（PEFR）已成为可能。然而，尽管当前的国家和国际指南建议通过传统的运行图监测PEFR，但患者和医生对其的使用仍然很少。探索了统计过程控制（SPC）理论和图表在家庭肺功能连续监测中的作用，并将其应用于哮喘患者的直接护理。该方法代表了专业知识和改进知识与持续改进、SPC、系统思维/系统动力学、范式以及学习社区/组织等相关学科的整合。
描述了在哮喘-过敏诊所及研究中心（路易斯安那州什里夫波特）对四名患者使用PEFR控制图的情况。良好哮喘控制的关键在于通过减少连续肺功能测量之间的差异来优化肺功能，从而产生一个安全的功能范围。了解系统中变异的类型（特殊原因或共同原因）有助于聚焦临床决策。例如，案例4中的一名11岁男孩展示了如何使用控制图来了解一种新吸入性糖皮质激素的效果。比较基线的最后14天和吸入性糖皮质激素开放标签使用的最后14天，实际PEFR值有明显改善——这一点运行图或均值比较很容易显示出来。控制图显示，该儿童基线时的护理过程在功能上有严重哮喘风险（个人最佳值的46%），新药物的效果不仅提高了平均功能，还将功能范围从个人最佳值的46% - 72%转变为78% - 102%。在这个新的功能范围内，患者的护理系统无法产生有严重哮喘风险的值。除非具体量化护理改变能够产生的功能范围，否则可能会对改善数据产生误解。
开发PEFR控制图的概念涉及审视和挑战在家中哮喘护理中监测PEFR的传统思维模式，更好地理解动态系统的运作并运用系统思维，以及与患者分享所学内容并征求他们的意见。
PEFR控制图采用了一个有趣的统计平台，能够将连续测量的知识和这些测量之间变异的知识整合到一个工具中，以便更好地评估所遵循的哮喘护理过程。该工具提供了临床见解、实用知识以及通过传统PEFR图表患者和医生无法获得的机会。
