Blood Pressure Measurement Techniques

Blood pressure measurement techniques

Abstract: This essay will talk about the basic unit of blood pressure and also on how blood pressure is measured using the different types of measurement techniques. The techniques that are introduced in the essay are indirect and non-invasive which are safe to be used. The four methods are through auscultation, oscillometric, through the finger cuff and also through the wrist type method which falls in the oscillometric category. For each method, there will be given explanations on how to use the devices and how the different devices function to produce the blood pressure readings.

1. Introduction

Every human being have different levels of blood pressure in their body. Blood pressure is

Why is this so? It is because a higher amount of force is needed to be exerted to move the water through the small pipe as compared to the larger pipe. The more water to be transported, the higher the pressure is needed. So in the arteries of the human being, if its pathway is blocked by fatty deposits, the walls becomes smaller and the heart has to pump a higher amount of pressure to get the blood flowing through, resulting in hypertension. In order to check if a patient is suffering from hypertension or abnormal levels of blood pressure, there are four indirect and non-invasive methods to assess the patient. The methods are auscultation, oscillometric, through the wrist type method or through the finger cuff method.

2. Auscultation Method

Auscultation method are often used in the clinics and hospitals by the doctors manually. This method requires the observer to listen to the Korotkoff sounds produced when the blood flow is constricted. One common instrument being used would be the sphygmomanometer, otherwise known as the blood pressure cuff. A sphygmomanometer is made up of an inflatable rubber cuff connected to a rubber squeeze ball which is manually activated to pump and release air, a mercury manometer which indicates the pressure and a stethoscope. (Skills,

The wrap around the wrist acts as an amplifier which calibrate the different measurements taken from the finger to the arm where the monitor is at. It changes the readings into numerical values of blood pressure. The cuff contains a light emitting diode that shines light through the finger and can be identified on another side of the cuff. The tissues in the finger will absorb light and the amount of light absorbed is equivalent to the volume of tissue through which it goes through. Each cardiac cycle results in the volume of blood in the finger to change and also the amount of light absorbed. So as to maintain the amount of light absorbed constant, both the volume and pressure applied in the finger have to be kept constant as well. The pressure that is applied produces a waveform which corresponds to the pressure of blood in the arterial which produces another waveform, to the finger. Hence the result can be displayed as waveforms and also includes the numerical values of systolic readings and diastolic readings. (Biopac, 2015) Figure 5: A finger cuff device Unlike the other methods, a finger cuff device are not used often as the data are conflicting in relation to the validity of readings taken. It is not highly recommended to users that have hypotension or those with