APD to Measure the Resistance of the Respiratory System

描述（由申请人提供）：呼吸系统筛查和诊断在当今的医疗保健中很重要。在美国，哮喘和慢性阻塞性肺病（COPD）构成了主要的健康问题。机械呼吸机越来越多地用于严重呼吸系统疾病患者的生命支持。传统的肺功能测试（肺活量测定法）往往不足以提供卫生保健专业人员所需的呼吸功能信息。气流扰动装置（APD）在过去几年中经历了重大改进。APD在概念上很简单，在流道中使用一个旋转轮来改变20-45%的流量，同时伴随着口压的微小变化。根据这些变化，计算阻力。APD操作简单，只需要一分钟的正常呼吸，对儿童和成人都有用。APD可以实时显示阻力变化，并且可以修改为测量通气患者的阻力，并且可以像相机一样便携。我们已经使用APD来测量近1500人的平均呼吸阻力，以及单独的吸气和呼气值。I期临床数据显示，在相同的测量中，APD的标准偏差（SD）小于IOS。现有的竞争性商业肺功能测试（PFT）设备包括肺活量计、强制振荡（FO，例如IOS）和中断器（Rint）。这些方法要么需要患者用力呼气（肺活量计），要么非常昂贵且对气流泄漏非常敏感（强制振荡，FO，如IOS），要么需要完全中断气流，限制每3次呼吸仅获得一次测量数据（Rint）。APD的三个主要优点包括只需要自然呼吸，气流泄漏的影响比FO相对较小，它提供的测量量比Rint多一个数量级。APD可用于幼儿，成人病人和老年患者。第一阶段的资金使我们能够将APD大幅推进到目前的配置。第一阶段前期APD重量/成本为10磅/ 3500美元。APD现在是14.7盎司/ 600美元，可携带。在第二阶段，我们计划进一步减小其尺寸和成本，提高流量传感器的精度和灵敏度，并增加额外的功能，包括流量体积显示。为了将APD投入商业生产（我们的长期目标），进一步的改进是必要的。在此之后，必须获得临床数据，并寻求监管部门的批准。APD的市场是巨大的，包括医院、诊所、医生办公室、救护车和家庭护理设施。由于APD的尺寸、成本和操作简便，它是家庭使用和新药药物测试的理想设备。在第二阶段，我们计划在4个不同诊所的至少1750个人身上测试该设备。慢性阻塞性肺疾病（COPD）是美国第四大死亡原因；哮喘和慢性阻塞性肺病的呼吸系统筛查以及治疗干预措施的监测在美国卫生保健中很重要。由于其体积小，成本适中，易于操作和对小气道功能的敏感性，所提出的装置（APD）可以有效和经济地筛查呼吸系统疾病，并监测COPD和其他呼吸系统疾病患者的干预措施。这将提高诊断和对治疗益处的认识，并降低保健费用。

DESCRIPTION (provided by applicant): Respiratory screening and diagnosis are important in today's health care. Asthma and chronic obstructive pulmonary disease (COPD) constitute major health problems in the US. Mechanical ventilators are used increasingly for life support in patients with serious respiratory illness. Traditional pulmonary function tests (spirometry) are often not adequate to provide the respiratory functional information required by health care professionals. The Airflow Perturbation Device (APD) has undergone significant improvements over several years. APD is simple in concept, employing a rotating wheel in the flow path to change flow by 20-45%, with associated small changes in mouth pressure. From these changes, resistance is calculated. APD is simple in operation, requiring only normal breathing for one minute and is useful in children as well as adults. APD can display resistance changes in real time, and can be modified to measure resistance of ventilated patients and made as portable as a camera. We have used APD it its current implementation to measure average respiratory resistance, as well as separate inspiratory and expiratory values, in nearly 1,500 people. The Phase I clinical data shows that the Standard Deviation (SD) for APD is smaller than IOS on identical measurements. Existing competitive commercial Pulmonary Function Testing (PFT) devices include spirometry, forced oscillation (FO, e.g. IOS), and interrupter (Rint). These either require patients to forcefully exhale (spirometers), or are very expensive and very sensitive to airflow leak (forced oscillation, FO, such as IOS), or require complete interruption of airflow limiting data acquired to only one measurement every 3 breaths (Rint). Three major advantages of APD include a requirement for natural breathing only, relatively less effect from airflow leak than in FO, and it provides an order of magnitude more measurements than Rint. APD can be used by young children, ill adults and in elderly patients. Phase I funding enabled us to considerably advance APD to its current configuration. Pre-Phase I APD weight/cost were 10 pounds/$3,500. APD is now 14.7 ounces/$600, and portable. In Phase II we plan to further reduce its size and cost, improve the flow sensor's accuracy and sensitivity, and add additional capabilities including flow-volume display. To bring APD into commercial production (our long term objective), further refinements are necessary. After that, clinical data must be obtained, and regulatory approval must be sought. The market for the APD is huge, including hospitals, clinics, physician's offices, ambulances, and home care facilities. Because of its size and cost and ease of operation, the APD is an ideal device for home use and for pharmaceutical testing of new drugs. In Phase II we plan to test the device on at least 1,750 individuals at 4 different clinics. Chronic obstructive pulmonary disease (COPD) is fourth leading cause of death in the United States; and respiratory screening for Asthma and COPD, and monitoring of therapeutic interventions are important in US health care. Because of its small size, modest cost, ease of operation and sensitivity to small airway function, the proposed device (APD) can effectively and economically screen for respiratory disease, and monitor interventions in patients with COPD and other respiratory disorders. This will improve diagnosis and recognition of therapeutic benefits as well as lower the cost of the health care.