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https://www.readbyqxmd.com/read/27195632/blood-pressure-monitoring-for-the-anesthesiologist-a-practical-review
#1
Karsten Bartels, Stephen A Esper, Robert H Thiele
Periodic, quantitative measurement of blood pressure (BP) in humans, predating the era of evidence-based medicine by over a century, is a component of the American Society of Anesthesiologists standards for basic anesthetic monitoring and is a staple of anesthetic management worldwide. Adherence to traditional BP parameters complicates the ability of investigators to determine whether particular BP ranges confer any clinical benefits. The BP waveform is a complex amalgamation of both antegrade and retrograde (reflected) pressure waves and is affected by vascular compliance, distance from the left ventricle, and the 3D structure of the vascular tree...
June 2016: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/26998648/noninvasive-hemodynamic-measurements-during-neurosurgical-procedures-in-sitting-position
#2
Patrick Schramm, Irene Tzanova, Tilman Gööck, Frank Hagen, Irene Schmidtmann, Kristin Engelhard, Gunther Pestel
BACKGROUND: Neurosurgical procedures in sitting position need advanced cardiovascular monitoring. Transesophageal echocardiography (TEE) to measure cardiac output (CO)/cardiac index (CI) and stroke volume (SV), and invasive arterial blood pressure measurements for systolic (ABPsys), diastolic (ABPdiast) and mean arterial pressure (MAP) are established monitoring technologies for these kind of procedures. A noninvasive device for continuous monitoring of blood pressure and CO based on a modified Penaz technique (volume-clamp method) was introduced recently...
March 18, 2016: Journal of Neurosurgical Anesthesiology
https://www.readbyqxmd.com/read/26531867/reduced-baroreflex-sensitivity-in-patients-with-vasovagal-syncope
#3
P Mitro, M Simurda, L Evin, P Murin, E Muller
OBJECTIVES: The evidence is conflicting regarding the role of baroreflex in patients with vasovagal syncope. The aim of the study was to measure baroreflex sensitivity (BRS) and hemodynamic parameters during head up tilt test (HUT) with nitroglycerine stimulation. METHODS: Nitroglycerine stimulated HUT was performed in 51 patients with the history of recurrent syncope (mean age 46±19 years, 18 men, 23 women). Cardiac output (CO), stroke volume (SV), left-ventricular ejection time (LVET) and total peripheral resistance (TPR) were assessed during HUT by volume-clamp method using a beat-to-beat photopletysmography...
2015: Bratislavské Lekárske Listy
https://www.readbyqxmd.com/read/26335905/noninvasive-pulse-pressure-variation-and-stroke-volume-variation-to-predict-fluid-responsiveness-at-multiple-thresholds-a-prospective-observational-study
#4
Jaap Jan Vos, Marieke Poterman, Pieternel Papineau Salm, Kai Van Amsterdam, Michel M R F Struys, Thomas W L Scheeren, Alain F Kalmar
BACKGROUND: Pulse pressure variation (PPV) and stroke volume variation (SVV) are dynamic preload variables that can be measured noninvasively to assess fluid responsiveness (FR) in anesthetized patients with mechanical ventilation. Few studies have examined the effectiveness of predicting FR according to the definition of FR, and assessment of inconclusive values of PPV and SVV around the cut-off value (the "grey zone") might improve individual FR prediction. We explored the ability of noninvasive volume clamp derived measurements of PPV and SVV to predict FR using the grey zone approach, and we assessed the influence of multiple thresholds on the predictive ability of the numerical definition of FR...
November 2015: Canadian Journal of Anaesthesia, Journal Canadien D'anesthésie
https://www.readbyqxmd.com/read/26286887/blood-pressure-monitoring-during-exercise-comparison-of-pulse-transit-time-and-volume-clamp-methods
#5
Thomas Wibmer, Coy Denner, Christoph Fischer, Benedikt Schildge, Stefan Rüdiger, Cornelia Kropf-Sanchen, Wolfgang Rottbauer, Christian Schumann
During physical exercise, pulse transit time (PTT), expressed as the interval between ventricular electrical activity and peripheral pulse wave, may provide a surrogate estimate for blood pressure by the use of specific calibration procedures. The objective of this study was to determine systolic blood pressure (SBP) values derived from the PTT method and from an established method of non-invasive continuous blood pressure measurement based on the volume clamp technique, and to compare their agreement with sphygmomanometry during exercise tests...
2015: Blood Pressure
https://www.readbyqxmd.com/read/26286382/advances-in-photoplethysmography-beyond-arterial-oxygen-saturation
#6
REVIEW
Karsten Bartels, Robert H Thiele
PURPOSE: Photoplethysmography permits continuous measurement of heart rate and peripheral oxygen saturation and has been widely used to inform clinical decisions. Recently, a myriad of noninvasive hemodynamic monitoring devices using this same technology have been increasingly available. This narrative review aims to summarize the principles that form the basis for the function of these devices as well as to comment on trials evaluating their accuracy and clinical application. PRINCIPAL FINDINGS: Advanced monitoring devices extend photoplethysmography technology beyond measuring oxygen concentration and heart rate...
December 2015: Canadian Journal of Anaesthesia, Journal Canadien D'anesthésie
https://www.readbyqxmd.com/read/26230147/blood-pressure-monitoring-during-exercise-comparison-of-pulse-transit-time-and-volume-clamp-methods
#7
Thomas Wibmer, Coy Denner, Christoph Fischer, Benedikt Schildge, Stefan Rüdiger, Cornelia Kropf-Sanchen, Wolfgang Rottbauer, Christian Schumann
During physical exercise, pulse transit time (PTT), expressed as the interval between ventricular electrical activity and peripheral pulse wave, may provide a surrogate estimate for blood pressure by the use of specific calibration procedures. The objective of this study was to determine systolic blood pressure (SBP) values derived from the PTT method and from an established method of non-invasive continuous blood pressure measurement based on the volume clamp technique, and to compare their agreement with sphygmomanometry during exercise tests...
July 31, 2015: Blood Pressure
https://www.readbyqxmd.com/read/26227161/continuous-noninvasive-cardiac-output-determination-using-the-cnap-system-evaluation-of-a-cardiac-output-algorithm-for-the-analysis-of-volume-clamp-method-derived-pulse-contour
#8
Julia Y Wagner, Julian Grond, Jürgen Fortin, Ileana Negulescu, Miriam Schöfthaler, Bernd Saugel
The CNAP system (CNSystems Medizintechnik AG, Graz, Austria) provides noninvasive continuous arterial pressure measurements by using the volume clamp method. Recently, an algorithm for the determination of cardiac output by pulse contour analysis of the arterial waveform recorded with the CNAP system became available. We evaluated the agreement of the continuous noninvasive cardiac output (CNCO) measurements by CNAP in comparison with cardiac output measurements invasively obtained using transpulmonary thermodilution (TDCO)...
August 2016: Journal of Clinical Monitoring and Computing
https://www.readbyqxmd.com/read/25726179/continuous-noninvasive-arterial-pressure-measurement-using-the-volume-clamp-method-an-evaluation-of-the-cnap-device-in-intensive-care-unit-patients
#9
COMPARATIVE STUDY
Julia Y Wagner, Ileana Negulescu, Miriam Schöfthaler, Alexander Hapfelmeier, Agnes S Meidert, Wolfgang Huber, Roland M Schmid, Bernd Saugel
The CNAP system allows continuous noninvasive arterial pressure measurement based on the volume clamp method using a finger cuff. We aimed to evaluate the agreement between arterial pressure measurements noninvasively obtained using the CNAP device and arterial catheter-derived arterial pressure measurements in intensive care unit patients. In 55 intensive care unit patients, we simultaneously recorded arterial pressure values obtained by an arterial catheter placed in the abdominal aorta through the femoral artery (criterion standard) and arterial pressure values determined noninvasively using CNAP...
December 2015: Journal of Clinical Monitoring and Computing
https://www.readbyqxmd.com/read/25614597/effect-of-breath-holding-on-cerebrovascular-hemodynamics-in-normal-pregnancy-and-preeclampsia
#10
Teelkien R van Veen, Ronney B Panerai, Sina Haeri, Gerda G Zeeman, Michael A Belfort
Preeclampsia (PE) is associated with endothelial dysfunction and impaired autonomic function, which is hypothesized to cause cerebral hemodynamic abnormalities. Our aim was to test this hypothesis by estimating the difference in the cerebrovascular response to breath holding (BH; known to cause sympathetic stimulation) between women with preeclampsia and a group of normotensive controls. In a prospective cohort analysis, cerebral blood flow velocity (CBFV) in the middle cerebral artery (transcranial Doppler), blood pressure (BP, noninvasive arterial volume clamping), and end-tidal carbon dioxide (EtCO2) were simultaneously recorded during a 20-s breath hold maneuver...
April 1, 2015: Journal of Applied Physiology
https://www.readbyqxmd.com/read/25480763/measurement-of-blood-pressure
#11
Bernd Saugel, Ron Dueck, Julia Y Wagner
Blood pressure is overwhelmingly the most commonly measured parameter for the assessment of haemodynamic stability. In clinical routine in the operating theatre and in the intensive care unit, blood pressure measurements are usually obtained intermittently and non-invasively using oscillometry (upper-arm cuff method) or continuously and invasively with an arterial catheter. However, both the oscillometric method and arterial catheter-derived blood pressure measurements have potential limitations. A basic technical understanding of these methods is crucial in order to avoid unreliable blood pressure measurements and consequential treatment errors...
December 2014: Best Practice & Research. Clinical Anaesthesiology
https://www.readbyqxmd.com/read/25446701/cerebral-autoregulation-in-different-hypertensive-disorders-of-pregnancy
#12
Teelkien R van Veen, Ronney B Panerai, Sina Haeri, Jasbir Singh, Jasvant A Adusumalli, Gerda G Zeeman, Michael A Belfort
OBJECTIVE: Cerebrovascular complications that are associated with hypertensive disorders of pregnancy (preeclampsia, chronic hypertension [CHTN], and gestational hypertension [GHTN]) are believed to be associated with impaired cerebral autoregulation, which is a physiologic process that maintains blood flow at an appropriate level despite changes in blood pressure. The nature of autoregulation dysfunction in these conditions is unclear. We therefore evaluated autoregulation in 30 patients with preeclampsia, 30 patients with CHTN, and 20 patients with GHTN and compared them with a control group of 30 normal pregnant women...
April 2015: American Journal of Obstetrics and Gynecology
https://www.readbyqxmd.com/read/25429784/relating-external-compressing-pressure-to-mean-arterial-pressure-in-non-invasive-blood-pressure-measurements
#13
K Y Chin, R B Panerai
Arterial volume clamping uses external compression of an artery to provide continuous non-invasive measurement of arterial blood pressure. It has been assumed that mean arterial pressure (MAP) corresponds to the point where unloading leads to the maximum oscillation of the arterial wall as reflected by photoplethysmogram (PPG), an assumption that has been challenged. Five subjects were recruited for the study (three males, mean age (SD) = 32 (15) years). The PPG waveform was analysed to identify the relationship between the external compressing pressure, PPG pulse amplitude and MAP...
January 2015: Journal of Medical Engineering & Technology
https://www.readbyqxmd.com/read/25427990/blood-pressure-changes-after-high-and-low-salt-diets-are-intermittent-arm-measures-and-beat-by-beat-finger-measures-equivalent
#14
P Castiglioni, G Parati, M Di Rienzo, V Brambilla, L Brambilla, M Gualerzi, D Lazzeroni, P Coruzzi
The assessment of sodium sensitivity requires to measure the difference in mean arterial pressure (MAP) at the end of sodium-loading (SLoad) and sodium-depletion (SDepl) maneuvers with an arm-cuff manometer. Aim of this study is to evaluate whether MAP measuring devices based on the volume-clamp method at the finger can also be used for assessing sodium sensitivity. Sixty-eight normotensive volunteers underwent SLoad and SDepl diets in random order. MAP was simultaneously measured at the end of each diet with arm (Spacelabs 90207) and finger (Portapres model-2) cuff devices...
July 2015: Journal of Human Hypertension
https://www.readbyqxmd.com/read/24841333/continuous-non-invasive-monitoring-improves-blood-pressure-stability-in-upright-position-randomized-controlled-trial
#15
RANDOMIZED CONTROLLED TRIAL
Jan Benes, Alena Simanova, Tereza Tovarnicka, Silvie Sevcikova, Jakub Kletecka, Jan Zatloukal, Richard Pradl, Ivan Chytra, Eduard Kasal
Intermittent blood pressure (BP) monitoring is the standard-of-care during low and intermediate risk anaesthesia, yet it could lead to delayed recognition of BP fluctuations. Perioperative hypotension is known to be associated with postoperative complications. Continuous, non-invasive methods for BP monitoring have been developed recently. We have tested a novel non-invasive, continuous monitor (using the volume clamp method) to assist with maintaining BP in safe ranges for patients undergoing surgery in a beach chair position...
February 2015: Journal of Clinical Monitoring and Computing
https://www.readbyqxmd.com/read/24676438/initial-circulatory-response-to-active-standing-in-parkinson-s-disease-without-typical-orthostatic-hypotension
#16
Guillermo Delgado, Bruno Estañol, Mayela Rodríguez-Violante, Jesús Antonio González-Hermosillo, Óscar Infante-Vázquez
UNLABELLED: While the circulatory response to orthostatic stress has been already evaluated in Parkinson's disease patients without typical orthostatic hypotension (PD-TOH), there is an initial response to the upright position which is uniquely associated with active standing (AS). We sought to assess this response and to compare it to that seen in young healthy controls (YHC). METHOD: In 10 PD-TOH patients (8 males, 60 ± 7 years, Hoehn and Yahr ≤ 3) the changes in systolic blood pressure (SBP) and heart rate that occur in the first 30 seconds (sec) of standing were examined...
March 2014: Arquivos de Neuro-psiquiatria
https://www.readbyqxmd.com/read/24104783/cerebral-autoregulation-in-normal-pregnancy-and-preeclampsia
#17
Teelkien R van Veen, Ronney B Panerai, Sina Haeri, Annemiek C Griffioen, Gerda G Zeeman, Michael A Belfort
OBJECTIVE: To test the hypothesis that preeclampsia is associated with impaired dynamic cerebral autoregulation. METHODS: In a prospective cohort analysis, cerebral blood flow velocity of the middle cerebral artery (determined by transcranial Doppler), blood pressure (determined by noninvasive arterial volume clamping), and end-tidal carbon dioxide were simultaneously collected during a 7-minute period of rest. The autoregulation index was calculated. Values of 0 and 9 indicated absent and perfect autoregulation, respectively...
November 2013: Obstetrics and Gynecology
https://www.readbyqxmd.com/read/23852482/effect-of-valsalva-maneuver-induced-hemodynamic-changes-on-brain-near-infrared-spectroscopy-measurements
#18
Atsuhiro Tsubaki, Sho Kojima, Adriane Akemi Furusawa, Hideaki Onishi
Near-infrared spectroscopy (NIRS) is widely used to measure human brain activation on the basis of cerebral hemodynamic response. However, a limitation of NIRS is that systemic changes influence the measured signals. The purpose of this study was to clarify the relationship between NIRS signals and blood pressure during the Valsalva maneuver. Nine healthy volunteers performed a 20-s Valsalva maneuver to change their blood pressure. Changes in oxyhemoglobin (O2Hb) concentration were measured with 34 channels with an inter-optode distance of 30 mm for deep-penetration measurements (deepO2Hb) and 9 channels with an inter-optode distance of 15 mm for shallow-penetration measurements (shallowO2Hb)...
2013: Advances in Experimental Medicine and Biology
https://www.readbyqxmd.com/read/23524512/a-new-noninvasive-device-for-continuous-arterial-blood-pressure-monitoring-in-the-superficial-temporal-artery
#19
K Y Chin, R B Panerai
Continuous recording of arterial blood pressure (ABP) has many applications in cardiovascular physiology, but existing alternatives rely on measurements performed in the fingers or radial artery. Peripheral recordings have significant differences from central ABP regarding the pattern of the waveform and corresponding systolic and diastolic values. To address the need for noninvasive measurements closer to the ascending aorta, a new device was constructed to measure ABP in the superficial temporal artery (STA) using photoplethysmography and the arterial volume clamping technique...
April 2013: Physiological Measurement
https://www.readbyqxmd.com/read/23302972/peripheral-perfusion-index-as-an-early-predictor-for-central-hypovolemia-in-awake-healthy-volunteers
#20
Michel E van Genderen, Sebastiaan A Bartels, Alexandre Lima, Rick Bezemer, Can Ince, Jan Bakker, Jasper van Bommel
BACKGROUND: In healthy volunteers, we investigated the ability of the pulse oximeter-derived peripheral perfusion index (PPI) to detect progressive reductions in central blood volume. METHODS: Twenty-five awake, spontaneously breathing, healthy male volunteers were subjected to progressive reductions in central blood volume by inducing stepwise lower body negative pressure (LBNP) with 20 mm Hg for 5 minutes per step, from 0 to -20, -40, -60, and back to 0 mm Hg...
February 2013: Anesthesia and Analgesia
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