A novel method for measuring blood pressure

血压是由心脏产生的压力，它推动血液循环，为大脑和肾脏等重要器官提供血液。测量血压在很多情况下都很重要：高血压会给心脏带来压力，并可能导致心脏病发作和中风；低血压会导致重要器官衰竭；在怀孕期间，高血压通常是先兆子痫的征兆，这是一个潜在的严重问题。一种老式的测量血压的方法是给上臂周围的橡胶袖带充气，用水银柱测量袖带中的压力，然后用听诊器听手臂动脉上方的声音。虽然这可能是最准确的方法，但由于难以准确执行，而且汞具有潜在危险，因此正在逐步淘汰。现有的自动电子测量方法不如汞法准确，特别是在怀孕和运动期间（另一种准确测量血压很重要的情况）。这两种方法对重病患者都不起作用。我们开发了一种新方法，该方法是在检测下臂动脉的压力变化或运动的同时，在上臂周围充气一个血压袖带。当袖带的压力大于动脉的血压时，动脉壁就会被压扁，这就改变了手臂下面动脉的运动。这项研究的目的是开发一种软件，使这种方法自动工作，并检查它在某些情况下是否有效，比如在运动期间、怀孕期间和危重病人身上。

Blood pressure is the pressure generated by the heart to push blood around the circulation to supply vital organs like the brain and the kidneys. Measurement of blood pressure is important in many situations: high blood pressure puts a strain on the heart and can lead to heart attacks and strokes; low blood pressure can cause vital organs to fail; during pregnancy high blood pressure is often the sign that pre-eclampsia , a potentially serious problem, is developing. An old fashioned method for measuring blood pressure involves inflating a rubber cuff around the upper arm, measuring the pressure in the cuff with a column of mercury and listening to sounds over the artery in the arm with a stethoscope. Although probably the most accurate method, it is being phased out because it is difficult to perform accurately and mercury is potentially hazardous. Existing automatic electronic methods are less accurate than the mercury method especially in pregnancy and during exercise (another situation in which accurate measurement of blood pressure is important). Neither method works well in seriously ill patients. We have developed a new method based upon detecting changes in pressure or movement of the artery in the lower arm while a blood pressure cuff is inflated around the upper arm. When pressure in the cuff becomes greater than blood pressure in the artery, the artery wall becomes squashed and this changes the movement of the artery further down the arm. The purpose of this research is to develop software that will make this method work automatically and to check that it works well in certain situations such as during exercise, in pregnancy and in critically ill patients.