APD to Measure the Resistance of the Respiratory System

描述(由申请人提供)：呼吸筛查和诊断在当今的医疗保健中很重要。哮喘和慢性阻塞性肺疾病(COPD)是美国的主要健康问题。机械呼吸机越来越多地被用于严重呼吸系统疾病患者的生命维持。传统的肺功能测试(肺活量测定)往往不足以提供卫生保健专业人员所需的呼吸功能信息。气流扰动装置在过去几年中有了很大的改进。Apd的概念很简单，在流道中使用一个旋转的轮子来改变流量20%-45%，同时伴随着口腔压力的微小变化。根据这些变化，可以计算出阻力。Apd操作简单，只需要正常呼吸一分钟，对儿童和成人都很有用。Apd可以实时显示阻力变化，可以进行修改以测量呼吸机患者的阻力，并使其像相机一样便携。我们已经使用apd测量了近1500人的平均呼吸阻力，以及吸气值和呼气值。I期临床数据显示，在相同的测量条件下，APD值的标准差(SD)小于IOS。现有的竞争性商用肺功能测试(PFT)设备包括肺活量测定仪、强迫振荡(FO)和断续器(RINT)。这些方法要么要求患者用力呼气(肺活量计)，要么非常昂贵且对气流泄漏非常敏感(强迫振荡，FO，如IOS)，或者要求完全中断气流限制数据，仅采集每3次呼吸一次(Rint)。它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，它提供的测量比Rint多一个数量级。儿童、患病成人和老年患者均可使用雪崩止痛器。第一阶段的资金使我们能够相当大地提高apd到其目前的配置。在第一阶段之前，apd的重量/成本是10磅/3500美元。Apd现在的价格是14.7盎司/600美元，而且是便携的。在第二阶段，我们计划进一步缩小其尺寸和成本，提高流量传感器的精度和灵敏度，并增加包括流量显示在内的额外功能。为了将apd投入商业生产(我们的长期目标)，需要进一步完善。在此之后，必须获得临床数据，并必须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。由于其体积小、成本高、操作简单，该设备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家不同诊所的至少1750人身上测试该设备。慢性阻塞性肺疾病(COPD)是美国第四大死因；哮喘和COPD的呼吸道筛查和治疗干预监测在美国医疗保健中非常重要。由于其体积小、成本适中、操作简单以及对小气道功能的敏感性，建议的设备(APD)可以有效且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，并降低医疗保健的成本。

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.