Blood pressure accuracy

There has not been any prior analytical investigation of the arterial stiffening theory of pseudohypertension. The low arterial comphance theory is tested in this chapter via a mathematical model of oscillometric blood pressure measurement. The computational model will be used to evaluate measurement error introduced by arterial disease or alterations in arterial mechanics in general. Once these errors are established, the model will then be used to investigate the means by which automated blood pressure monitor may detect the occurrence of pseudo-hypertension or provide a correction method by which blood pressure accuracy is unproved even in the presence of arterial disease. 

To develop the experimental model (stiff artery theory), the arterial mechanics was completely modeled by Equation 12.1. The parameters of this equation represent the artery stiffness over varied ranges of pressure. Because it was not fully understood how the arterial mechanics and its pressure area function change with disease, the approach taken here was to perform an evaluation of parametric sensitivity. The mechanical parameters a, b, c, and d were varied to detect their influence on blood pressure accuracy. The results of the model for control and experimental conditions are provided below. 

Carbon dioxide gas is used to immobilize animals prior to slaughtering them (46). In addition to providing a humane slaughtering technique, this results in better quaHty meat. The CO2 increases the animal s blood pressure, thereby increasing blood recovery. The increased accuracy obtainable in the killing operation reduces meat losses because of cut shoulders. 

Supervises the patient and a family member during several trial blood pressure readings to ensure accuracy of the measurements. 

The curve can be any non-linear shape to demonstrate the effect. The curve helps to explain the importance and limitations of calibration. Points A and B represent a calibration range of input values between which linearity is likely. The curve demonstrates how linearity cannot be assured outside this range. The DINAMAP monitor behaves in a similar way. It tends to overestimate at low blood pressure (BP) and underestimate at high BP while retaining accuracy between the calibration limits. 

How to test the accuracy of an electronic blood pressure device... 

This last point is very important in two ways. First, throughout this book, the importance of optimum quality data is emphasized many times. In most cases, this comment is associated with acquiring the data, for example, measuring blood pressure as accurately as possible. However, since all of these data are entered into databases, data entry must be accurate A correct measurement that is stored incorrectly immediately lessens the quality of the overall data. Sometimes data are transferred from a measurement device electronically to the database, and sometimes data are manually entered into the database. Procedures to ensure accuracy, correctness, and completeness of data transfer are an essential part of data recording and management. Second, the storage of sensitive data (personal, medical) and proprietary data requires additional considerations to ensure that these data do not become accessible and available to unauthorized users. 

In a nutshell, this book s program will show you ways to attain a healthy weight, cope with stress, get the physical activity you need without having to go to the gym, enjoy a delicious diet that actually lowers blood pressure without deprivation, and use newly researched supplements that often can be just as effective as prescription drugs. The concepts are all based on research done at the world s top medical centers and published in the most prestigious journals. And I ve had physicians review what I ve written to assure absolute accuracy. I ve done my part. I ve controlled my own blood pressure, and I m sharing the information I ve learned with you. Now it s up to you to do your part. 

Some medical offices now use a digital apparatus to test blood pressure, reducing the environmental impact of mercury. But the mercury sphygmomanometer is still considered the gold standard and is used to calibrate the accuracy of other devices. 

Even though the home monitoring devices are extremely easy to use, technique is important to assure accurate blood pressure measurements. It s best to sit at a table or a desk, wrap the cuff around the arm as directed in the instructions, and relax for a couple of minutes before inflating the cuff. Keep both feet on the floor and try to remain still, since movement can decrease accuracy. Your arm and cuff should be at the same height as your heart. Hit the start button and note your blood pressure. Many machines also measure heart rate. Wait a couple more minutes and repeat the procedure. You ll probably find that the first measurement is higher. 

Blood pressure testing in doctors offices may be inaccurate owing to anxiety or other factors. For a diagnosis of hypertension, physicians take measurements on three separate visits with patients seated with feet on the floor, back supported in a chair, and relaxed. Today s home blood pressure monitoring devices have been shown to be as accurate as or even more accurate than in a doctor s office. A good brand to consider for your home is Omron select a device with a cuff that goes around the upper arm rather than the wrist for greatest accuracy. I believe that home blood pressure monitors should be as common as scales. 

FIGURE A—1 The prescription. The prescription must be carefully prepared to identify the patient and the medication to be dispensed, as well as the manner in which the drug is to be administered. Accuracy and legibility are essential. Use of abbreviations, particularly Latin, is discouraged, as it leads to dispensing errors. Inclusion of the purpose of the medication in the subscription (e.g., control of blood pressure") can prevent errors in dispensing. For example, the use of losartan for the treatment of hypertension may require 100 mg/day (1.4 mg/kg per day), whereas treat-... 

Hence, this pulse is the input to the model and is only dependent on time. For any model condition, the systolic and diastolic pressure would remain fixed at these values. The modeled computer subject will always have a constant known blood pressure of 112/73 mmHg so that accuracy of blood pressure measurement can be easily assessed. 

Because the arterial pressure pulse sets the systolic and diastolic pressure at 112 and 73 mmHg, respectively, the effect of any artery parameter may be easily observed. To discover the effect of each arterial parameter on blood pressure determination accuracy, each artery parameter was varied separately by a... 

In the cuff pressure VS area model, the c parameter was still the source of error, especially for diastolic pressure. It caused pseudo-systolic hypotension and pseudo-diastohc hypertension. By comparing a large pulse to a small one, we noticed that the derivative went low in the high-pressure zone for the diseased artery and this did not happen for the normal artery therefore, we came up with a new rule that we call the oscillometry of false hypertension. At high blood pressure zone with the derivative less than 0.1, the artery is diseased and stiff, and it collapses easily. As mentioned earlier, the true measurement of the blood pressure should be independent of the arterial mechanics. However, in every modeling experiment, it was found that c was the source of error and its related plot was very different from the rest. Other parameters like a, b, and d did not change the accuracy of blood pressure measurement before and after normalization. Normalization did not even correct the inaccuracy caused by the c parameter. In the case of the diseased artery, the arterial stiffness did increase diastolic pressure by almost 8% (Table 12.2) and this was consistent with the theory of pseudo-hypertension. 

Monitoring, analytic. Blood pressure monitors Security, trust, accuracy,... 

Santamore WP, Homko CJ, Kashem A, McConnell TR, Menapace FJ, and Bove A A. Accuracy of blood pressure measurements transmitted through a telemedicine system in underserved populations. Telemedicine Journal and E-health. 2008 14(4) 333-338. 

Barometry has ubiquitous applications, measured by a broad variety of sensors. It is key to weather prediction and measuring the altitude of aircraft as well as to measuring blood pressure to monitor health. Pressure-sensitive paints enable measurement of surface pressure as it changes in space and time. The accuracy of measuring and controlling gas pressure is fundamental to manufacturing processes. 

Gill DG, Mendes de CB, Cameron JS, Joseph MC, Ogg CS, Chantler C (1976) Analysis of 100 children with severe and persistent hypertension. Arch Dis Child 51 951-956 Goonasekera CD, Dillon MJ (2000) Measurement and interpretation of blood pressure. Arch Dis Child 82 261-265 Minty I, Lythgoe MF, Gordon I (1993) Hypertension in paediatrics can pre- and post-captopril technetium-99m dimercaptosuccinic acid renal scans exclude renovascular disease Eur J Nucl Med 20 699-702 Ng CS, de Bruyn R, Gordon 1 (1997) The investigation of renovascular hypertension in children the accuracy of radio-isotopes in detecting renovascular disease. Nucl Med Commun 18 1017-1028... 

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