Electrohysterogram-based sensor for non-invasive contraction monitoring with impr

描述(由申请人提供)：在美国，大多数产科分娩都要接受持续的电子子宫活动监测。通常，使用外部测力仪(应变计)来提供子宫收缩的频率和时间。这种监护仪的可靠性取决于其正确的定位(可能会受到患者运动的干扰)，以及从子宫到传感器的张力传递。对于一些患者，特别是肥胖者，监护仪可能无法持续检测到宫缩。在其他情况下，监护仪需要护理人员频繁地重新定位。替代的子宫活动监测器是宫内压力导管(IUPC)，它通过子宫颈口放置在胎膜破裂的充分扩张的患者身上。虽然这种监护仪通常提供更可靠的信号，以及有关宫内压力的定量信息，但其侵袭性和感染风险的增加限制了其使用的热情。在美国，产科套房受到肥胖大流行的影响，这些女性出现分娩问题、感染和其他并发症的风险增加。现有的非侵入性子宫活动监测虽然更好地降低了感染风险，但在这一人群中尤其不可靠。这项拟议研究的具体目标是开发一种可靠的、非侵入性的子宫活动监测器，它不受肥胖的影响，需要的护理干预比产力计更少。最终产品将是一种智能电缆，它将现有的分娩监护仪连接到电极阵列，并将子宫的电活动(宫电或EHG)转换为与现有监护仪兼容的功率计信号。我们小组获得的初步结果表明，EHG可以提供这样的监测，但这些研究是使用位于母体腹部的10个电极进行的。我们提出了以下具体目标： 目标1：开发EHG信号处理和嵌入式软件：使用我们大型数据库中的回溯数据、信号处理算法来生成高质量的收缩曲线。将实施一项回顾性的临床解释研究，以验证最终的信号处理系统。 目的2：用嵌入式软件构建EHG系统硬件：将设计一个原型EHG放大系统，直接与现有的母婴监护仪接口。放大器信号将被处理，以创建子宫活动曲线，该曲线将被实时显示并记录下来，以供进一步分析。 目的3：临床评价微型阵列式EHG子宫活动监测仪：对30名患者进行初步研究，以评估微型阵列式EHG宫缩监测仪在活跃期监测宫缩的可靠性。EHG子宫活动度将与产力计和IUPC得出的结果进行比较，并通过电子和专家意见进行评估。公共卫生相关性：目前对子宫活动的非侵入性监测方法经常失败，特别是在肥胖患者中。当这种情况发生时，临床医生通常必须使用侵入性宫内压力导管，这在这些患者中尤其有问题，因为他们已经面临着更高的感染风险。开发一种替代的、非侵入性的子宫活动监测仪，在肥胖患者和至少在正常体重的患者中表现更好，将通过限制侵入性监测的需要而减少感染并发症，同时需要更少的护理操作。

DESCRIPTION (provided by applicant): The majority of obstetric deliveries in the US undergo continuous electronic uterine activity monitoring. Typically, an external tocodynamometer (strain gauge) is employed to provide the frequency and timing of uterine contractions. The reliability of this monitor depends on its proper positioning (which may be disturbed by patient movement), and the transmission of tension from the uterus to the sensor. In some patients, particularly the obese, the monitor may fail to detect contractions consistently. In others the monitor requires frequent repositioning by the nursing staff. The alternative uterine activity monitor is an intrauterine pressure catheter (IUPC), which is placed through the cervical os in the adequately dilated patient with ruptured membranes. While this monitor usually provides a more reliable signal, as well as quantitative information regarding intrauterine pressure, its invasive nature and increased risk of infection limit enthusiasm for its use. The obstetric suite is subject to the obesity pandemic in the US, and these women have an increased risk for labor problems, infections and other complications. Existing non-invasive uterine activity monitoring, while preferable to reduce the infection risk, is particularly unreliable in this population. The specific goal of the proposed research is to develop a reliable, non-invasive uterine activity monitor that is unaffected by obesity and requires less nursing intervention than the tocodynamometer. The end-product will be a smart cable that connects an existing labor monitor to an electrode array and converts the electrical activity of the uterus (electrohysterogram or EHG) into tocodynamometer signals compatible with existing monitors. Preliminary results obtained by our group indicate that the EHG can provide such a monitor, however these studies were conducted with 10 electrodes located across the maternal abdomen. We propose the following specific aims: Aim 1: Develop EHG signal processing and embedded software: Using retrospective data from our large database, signal processing algorithms to produce high quality contraction curves. A retrospective clinical interpretation study will be implemented to validate final signal processing system. Aim 2: Build EHG system hardware with embedded software: A prototype EHG amplifier system will be designed to interface directly to existing maternal-fetal monitors. The amplifier signal will be processed to create uterine activity curves that will be displayed in real-time and recorded for further analysis. Aim 3: Clinically evaluate the mini-array EHG uterine activity monitor: A 30-patient pilot study will be conducted to evaluate the reliability of the mini-array for monitoring contractions during active labor. The EHG uterine activity will be compared with that derived from the tocodynamometer and IUPC, and evaluated both electronically and by expert opinion. PUBLIC HEALTH RELEVANCE: The current method of non-invasive monitoring of uterine activity fails frequently, particularly in the obese patient. When this occurs, often clinicians must use an invasive intra- uterine pressure catheter that is particularly problematic in these patients since they are already at increased risk for infections. The development of an alternative, non-invasive monitor of uterine activity that performs better in the obese patient and at least as well in the normal-weight patient, will reduce infectious complications by limiting the need for invasive monitoring while requiring less nursing manipulation.