Which of the following manometers consists of a cuff containing a bladder?
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An issue with any method using auscultation is the introduction of the phenomenon of terminal digit preference, and bias of the observer because of knowledge of previous measurements. Any instrument that eliminates or reduces these two is to be welcomed. This initially led to the development of the random-zero sphygmomanometer, which was developed and shown to minimise or eliminate both these items.12,13 Unfortunately, these devices were shown subsequently significantly to underestimate blood pressure, and were therefore abandoned.14,15 Show
Automated oscillometric devices have similarly been developed. These improve on the shortcomings of the auscultatory method by eliminating both terminal digit preference and the bias of the observer. They work by the detection of pressure pulses in the cuff. These are generated as a result of the volume pulses of the artery. When blood starts flowing through the artery at the point of systolic pressure, a pressure pulse is generated. As pressure within the deflating cuff is reduced in a stepwise manner, a series of pressure pulses generate the pulse oscillogram. The pulse amplitudes of this oscillogram provide an envelope curve, with the maximal value on this curve equating to the mean arterial pressure. Systolic and diastolic pressures are calculated from preset algorithms in the instrument microchip, and are a function of the mean. The algorithms are specific to the instrument, and are not declared by the manufacturers.16,17 Although these automated devices are increasingly being used in primary care and paediatric departments, there are some particular concerns that need to be highlighted. The Dinamap devices are the most commonly studied automated oscillometric devices reported in paediatric series. An earlier version of this device, model 1846 SX, had been shown to have superior correlation with intra-arterial measurements.18 Other studies, however, reported higher mean systolic measurements using models 1846, 8100, and 845 when compared with the random-zero sphygmomanometer and mercury sphygmomanometer.19,20 Diastolic measurements had been reported to have better agreement.19 A more recent report using the Dinamap 8100 monitor highlighted the discrepancy between the two methods, with measurements using the device higher by a mean of 10 mm Hg for systolic and 5 mm Hg for diastolic blood pressure.21 Although normative limits have been proposed using the Dinamap 8100 instrument, caution needs to be proposed before applying these limits in clinical practice.22 Another particular practical observation with oscillometric devices is the phenomenon of measurements being higher by about 3 to 5 mm Hg on first measurement, despite control of factors involving the patient, the observer, and the environment.20,23 The second reading has been reported to be more accurate. Automatically inflated cuffs have recently been introduced. These measure both systolic and diastolic pressures, recording the results at preset intervals by detecting oscillations in the pressure from the cuff. They are especially useful in the care of the critically ill child, saving nursing time and reducing disturbance to the patient. The calibration needs to be checked frequently if the result is to be regarded as accurate, but they are useful in detecting changes. Indeed, they will alarm automatically if preset parameters are exceeded. Aneroid sphygmomanometers have also gained in popularity in clinical practice because of their portability and their reliance on techniques similar to the standard mercury sphygmomanometer. Because of this, however, they have no influence on the biases existing with the mercury sphygmomanometer. The devices have proven their accuracy when regular 6-month maintenance is in place to service the instruments.24 The majority of devices in clinical use, nonetheless, have not been evaluated independently for accuracy using the two most widely accepted protocols for validation.25,26 These protocols have been proposed by the British Hypertension Society and the Association for the Advancement of Medical Instrumentation. Several updates of validation have been published, but the best method of finding up-to-date information is on the nonprofit Web site http://www.dableducational.com.27 View chapterPurchase book Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B978070203064200062X HypertensionJohn F. Potter, in Brocklehurst's Textbook of Geriatric Medicine and Gerontology (Seventh Edition), 2010 Measuring blood pressureWith the expected phasing out of mercury sphygmomanometers and their replacement by semiautomatic devices, it is important that manufacturers provide accurate equipment validated in the elderly. A list of BP measuring devices that have been validated for use in young and elderly persons is constantly updated on the British Hypertension Society Web site (www.bhsoc.org). Cuff size is important as undercuffing gives falsely high BP values. Cuff width should be equal to two thirds of the distance between axilla and antecubital fossa, and when the bladder is placed over the brachial artery, it should cover at least 80% of the arm’s circumference—which should be kept supported at heart level. Clinicians should obtain both standard and large cuffs and ensure they are used appropriately. The measurement should be taken in both arms initially because more than 10% of elderly people have at least a 10 mm Hg difference between arms. The arm with the highest reading should be used for subsequent measurements. All elderly people should have their BP measured every 5 years up to age 80 years at least, and in those with high normal BP (135 to 139/85 to 89 mm Hg) it should be assessed annually. View chapterPurchase book Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9781416062318100431 Neurologic Complications of HypertensionAnthony S. Kim, S.Claiborne Johnston, in Aminoff's Neurology and General Medicine (Fifth Edition), 2014 Evaluation and TreatmentThe gold standard of blood pressure measurement is auscultation using a mercury sphygmomanometer. Newer devices can provide accurate readings but require calibration. Blood pressure should be measured in the seated position after a 5-minute rest with the patient’s feet resting on the floor and the arm supported at heart level during the measurement. Accurate readings depend on the use of an appropriate-sized cuff with the bladder covering at least 80 percent of the arm. The classification of blood pressure into specific diagnostic categories is based on the average of two or more readings on each of two or more office visits.11 A complete history and physical examination with basic laboratory measurements are essential to evaluate for identifiable causes of hypertension and assess risk. Several patient characteristics may suggest an identifiable cause of hypertension including young age, severe hypertension, hypertension that is refractory to multiple interventions, and physical or laboratory findings suggestive of endocrinologic disorders, such as truncal obesity or hypokalemia. Abdominal bruits or decreased femoral pulses may also be an indicator of renovascular disease or coarctation of the aorta.12 Lifestyle modification is recommended as an initial therapy for patients with blood pressure of 120/80 mmHg or higher.5 Effective lifestyle interventions include weight loss, limited alcohol intake, aerobic physical activity, adequate potassium intake, reduction in sodium intake, and dietary regimens such as the Dietary Approaches to Stop Hypertension (DASH) eating plan.13 Antihypertensive medications are recommended in addition to lifestyle measures for patients with blood pressure of 140/90 mmHg or higher, with a lower threshold of 130/80 mmHg or higher in those with diabetes and chronic kidney disease. For patients without a history of cardiovascular disease or other compelling indication, initiating therapy with a thiazide diuretic such as chlorthalidone is generally recommended. In a trial involving more than 33,000 participants, therapy with chlorthalidone was either equivalent or superior to lisinopril and amlodipine for the primary prevention of cardiovascular end-points, with a particular benefit for African Americans in terms of both safety and efficacy.14 When the blood pressure is 160/100 mmHg or higher, initiating therapy with two-drug combinations is generally recommended.15 There are many benefits to treating hypertension, including a reduction in myocardial infarctions, congestive heart failure, retinopathy, renal failure, and overall mortality. The focus of the remainder of this chapter is on specific neurologic complications of hypertension and the unique aspects of treatment that they necessitate. View chapterPurchase book Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780124077102000072 HypertensionAmrit Singh, in Primary Care Geriatrics (Fifth Edition), 2007 BLOOD PRESSURE MEASUREMENT TECHNIQUEAneroid sphygmomanometers are most commonly used to measure blood pressures, but mercury sphygmomanometers seem to be the most accurate.46 An appropriate cuff size is essential to an accurate reading: the bladder length should be at least 75% to 80% of the circumference of the upper arm, and the width should be 40% of the arm circumference.2 Too small a cuff may produce an artificially elevated systolic blood pressure. Blood pressure should be measured with the patient comfortably seated for at least 5 minutes, and with the arm at heart level. Talking should be avoided as that may raise blood pressure transiently. More than one reading should be done, and each should be separated by at least 1 to 2 minutes.2,40,41,46,47 If two values in the same arm differ by more than 5 mmHg, subsequent readings should be taken until a reasonable average is achieved. The cuff should be inflated to 30 mmHg greater than the palpable systolic pressure, to avoid underestimating systolic blood pressure if an auscultatory gap is present.46 Auscultatory gaps involve disappearance of the Korotkoff sounds transiently as the cuff is deflated below the true systolic blood pressure; these gaps can be found in elderly patients, may be associated with increase risk of cardiovascular disease, and can lead to underestimation of systolic blood pressures.48 During deflation, the cuff should not be deflated faster than 2 to 3 mmHg per heartbeat.26,41,49 The blood pressure should also be measured in both arms, and in the event of a discrepancy, the arm with the higher pressure should be used for treatment decisions and for follow-up measurements.41,46,47 Smoking, ingesting caffeine, and exercising before blood pressure checks may affect the readings, so this should be considered when interpreting the readings. View chapterPurchase book Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780323039307500432 HypertensionElaine M. Urbina MD, Stephen R. Daniels MD, PHD, in Adolescent Medicine, 2008 BP MeasurementInstruments and techniques have direct effects on the accuracy of BP measurements. Mercury sphygmomanometers are the most accurate instruments, but their use is decreasing due to concerns about release of mercury into the environment. Aneroid manometers are the recommended alternative but must be recalibrated at least twice yearly. Oscillometric instruments are used when frequent BP readings are required or auscultation is difficult. Although more convenient than manometry, oscillometric measurements are approximately 10 mmHg higher and vary more across instruments than do manometric measurements. An oscillometric reading ≥ 90th percentile therefore should be rechecked by auscultation and manometry. Manometry, regardless of type, requires the use of a cuff that is sized appropriately. A cuff that is too small may yield a measurement that is falsely high, whereas a cuff that is too wide may yield a measurement that is falsely low. The width of the cuff bladder should equal approximately 40% of the mid-upper-arm circumference, and the bladder should encircle at least 80% of the limb circumference. Table 12-5 lists the recommended cuff bladder dimensions for children and adults. NHBPEP IV recommends the annual measurement of BP after the adolescent has been seated quietly for at least 5 minutes. The right arm should be positioned at heart level, and the stethoscope should be placed over the brachial artery pulse. The cuff should be inflated to a pressure 20–30 mmHg above systolic and then deflated at a rate of 2–3 mmHg per heartbeat. The pressure at which the pulse is first heard (i.e., Korotkoff Phase I) is the systolic BP. The pressure at which the pulse disappears (i.e., Korotkoff Phase V) is the diastolic BP. The measurement should be repeated at 1- to 2-minute intervals until two consecutive measurements differ by no more than 5 mmHg. View chapterPurchase book Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780323040730100123 PHYSICAL EXAMINATION PROCEDURESPATRICIA HRYNCHAK, in Clinical Procedures in Primary Eye Care (Third Edition), 2007 7.4.2 Advantages and disadvantagesThe gold standard for the measurement of blood pressure is the auscultatory method using an arm cuff and mercury sphygmomanometer (Kikuya et al. 2002). Most devices for measuring blood pressure occlude a blood vessel in an extremity (usually the arm, wrist or finger) with an inflatable cuff then measure the blood pressure either by detection of Korotkoff sounds or oscillometrically (Beevers et al. 2001). In the auscultatory method, a stethoscope is used on the brachial pulse to detect Korotkoff Phase I sound (the systolic blood pressure) and the cessation of the Korotkoff Phase V sounds (the diastolic pressure) on the deflation of the cuff. In this method the sphygmomanometer used to measure the pressure can be mercury, aneroid or electronic with a digital display. Mercury sphygmomanometers are accurate and affordable but have a limited future due to concerns about toxicity of mercury for users, personnel and the environment (WHO 2005). Aneroid devices are inexpensive and portable but the bellow-and-lever system used to measure pressure is subject to jolts and bumps which can lead to false readings (WHO 2005). Aneroid devices require regular calibration and should be checked against a mercury sphygmomanometer every 6 months. Hybrid devices use an electronic pressure gauge and display. Which of the following manometers consists of a cuff containing a bladder with an attached dial for reading blood pressure?sphygmomanometer, instrument for measuring blood pressure. It consists of an inflatable rubber cuff, which is wrapped around the upper arm and is connected to an apparatus that records pressure, usually in terms of the height of a column of mercury or on a dial (an aneroid manometer).
When obtaining blood pressure in children a cup with a bladder that covers which of the following areas of the upper arm should be selected?When obtaining blood pressures in children, a cuff with a bladder that covers which of the following areas of the upper arm should be selected? It should encircle the entire upper arm.
When wrapping the cuff around the patient's arm what distance should you keep between the end of the cuff and the antecubital fossa?The bottom edge of the cuff should be positioned approximately one inch (2-3 cm) above the antecubital fold. Wrap the end of the cuff not containing the bladder around the arm snugly and smoothly and engage adhesive strips.
Which of the following respiratory rates would be identified as normal for an infant?(1)(15) Normally, the newborn's respiratory rate is 30 to 60 breaths per minute.
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