A Digital Pressure Meter Equipped with Pressure Leak Detection

A manual sphygmomanometer is an instrument used to measure blood pressure, and consists of an inflatable cuff, a mercury manometer (or aneroid gauge) and an inflation ball and gauge. To assess the condition, accuracy and safety of mercury and anaeroid sphygmomanometers in use in general practice and to pilot a scheme for sphyg- momanometer maintenance within the district. Therefore, it must be calibrated periodically. Using the MPX 5050GP sensor as a positive pressure sensor. Requires a maximum pressure of 300 mmHg. This tool is also equipped with a SD Card as external storage. The display used in this module is TFT Nextion 2.8”. After conductings measurements of the three comparisons consisting of Multifunction, DPM and mercury tensimeter to 6 times, the smallest result 0 mmHg and the largest results 251.52 mmHg. While the error in mercury tensimeter’s of leak test to module and rigel is 0.56% and 0.404%.

Blood Pressure Measurement

Blood pressure measurement occurs either non-invasively or invasively, and usually refers to systemic arterial pressure measurement, but can also refer to systemic venous or pulmonary arterial pressure measurement. In 1733 the Reverend Stephen Hales was the first person to measure the blood pressure in vivo in unanaesthetised horses by direct cannulation of the carotid and femoral arteries. In doing so he observed the pulsatile nature of flow in the circulation. In 1828 Poiseuille developed the mercury manometer, and used it to measure blood pressure in a dog. The mercury manometer has, of course, become the standard technique against which other techniques are compared. The earliest numerical information on blood pressure measurement came from direct rather than indirect measurement in 1856 by Faivre, using Poiseuille’s device. However, in the last part of the nineteenth century, non-invasive measurement techniques were developed. In 1903, Codman and Cushing introduced the concept of routine intraoperative blood pressure measurement, which at the time was a revolutionary concept. Nowadays it is a fundamental part of minimal monitoring criteria. There are several techniques of non-invasive BP (NIBP) measurement, all of which function by occluding the pulse in a limb with a proximal cuff, then detecting its onset again distally, on lowering the cuff pressure. Detection methods include palpation, auscultation, plethysmography, oscillotonometry and oscillometry. Accuracy of all non-invasive techniques depends on cuff size in relation to the limb concerned, and over which artery the cuff is placed. Such techniques of NIBP measurement are necessarily intermittent. Much discussion has taken place on the accuracy of these devices, and the accuracy of diastolic pressure measurements needs improving, and there are ideas proposed for new non-invasive devices [Tooley and Magee 2009]. In the absence of a stethoscope, this technique is simple and reliable. After inflating the cuff on the upper arm to a pressure of above that of systolic, the cuff is then deflated while palpating the brachial artery and the systolic pressure is measured with a mercury column at first detection of the pulse. A study by van Bergen [1954] showed that BP can be underestimated by this method by up to 25% at 120 mmHg.

Casual and ambulatory blood pressure monitoring in children with renal scarring

INTRODUCTION Renal scarring is the most common cause of arterial hypertension in children. High blood pressure (BP) and microalbuminuria contribute to the progression of chronic renal disease. OBJECTIVE The aims of the study were: to assess BP in children with renal scarring by continuous ambulatory blood pressure measurement (ABPM) in comparison to the casual method (CBP), and to determine the correlation between ambulatory blood pressure (ABP) and/or casual blood pressure (CBP) values and proteinuria in children with renal scarring. METHOD This forward-looking study comprised thirty-five children (26 girls and 9 boys), aged between 3-13 years, 10.4?3.9, X+SD. Blood pressure was measured using the casual method (CBP) with a mercury manometer; BP was measured three times and the average was taken as a referent value. ABPM was performed using the oscillometric method with the Space Labs device, model 90207. RESULTS 45.71% of patients were classified as hypertensive by ABPM, while only 22.6% of CBP measurements were above the 95th percentile (p<0.01). "White coat hypertension" was present in 40% of the patients. Non-dipping BP alteration was detected in 37.14% of the patients. CONCLUSION Nocturnal systolic hypertension (systolic non-dipping alteration) is very frequent in children with renal scarring. Nocturnal diastolic blood pressure, detectable only via ABPM, is positively correlated with proteinuria and may be an initial sign of the progression of renal scarring. ABPM is more sensitive than CBP in the evaluation of BP in children with renal scarring.

Cluster Headache: Interictal Asymmetric Increment in Intraocular Pressure Elicited by Valsalva Manoeuvre

Changes in intraocular pressure (IOP) elicited by a Valsalva manoeuvre were studied in 11 male patients (mean age 39.8 years) suffering from episodic cluster headache (CH), and 12 healthy male controls (mean age 39.9 years). The tests were performed at rest and while exhaling hard through a mouthpiece connected to a mercury manometer. In the CH group, during symptomatic periods, between attacks, Valsalva manoeuvre elicited an asymmetric increase in IOP with significantly higher values on the symptomatic side ( P = 0011), whereas no asymmetric increments in IOP were found during asymptomatic periods. Outside the cluster period the IOP values both baseline and with Valsalva manoeuvre did not differ from controls. The increment in IOP took place within a few seconds, as in spontaneous CH attacks, thus pointing to a rapid increase in intraocular blood volume or vasodilatation. These findings may reflect a latent increased vascular reactivity of the symptomatic orbit during CH period.