Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 10 )

2018 ( 175 )

2017 ( 183 )

2016 ( 228 )

Custom range...

Search Results: 1 - 10 of 8934 matches for " Cardiac output measurement "
All listed articles are free for downloading (OA Articles)
Page 1 /8934
Display every page Item
Equipment review: An appraisal of the LiDCO?plus method of measuring cardiac output
Rupert M Pearse, Kashif Ikram, John Barry
Critical Care , 2004, DOI: 10.1186/cc2852
Abstract: This issue of Critical Care launches the first review in the new Health Technology Assessment section. As outlined in the editorial [1], the format is a combination of information from the developer and a balanced independent review. These articles should be read in conjunction as they are designed to assess the technology from two different perspectives.The technology under review is a continuous cardiac output monitor based on lithium dilution (LiDCO?plus, LiDCO Ltd, Cambridge, UK). The first section is based on a structured questionnaire derived from the SCCM Working Group of HTA [2]. This provides answers from the manufacturer relating to the technology's background, usage and outcome data. The responses are presented unaltered for the reader to form their own opinion. Clearly there is a potential for product promotion, but the formalised structure and narrow scope of the questions are designed to minimise this. There then follows a review by Dr Rupert Pearce, who has experience with the technology but no competing interests.We hope this combination of articles will provide some added value in an area of our specialty where the truth often lies buried. The questionnaire-and-review structure of the assessment is intended as a template for development of the HTA section, and will be maintained as a consistent format for future device reviews.Kashif Ikram and John BarryThe PulseCO? system calculates continuous beat-to-beat cardiac output by analyzing the arterial blood pressure trace following calibration with the absolute LiDCO cardiac output value. This system has been shown to be accurate and reliable in various clinical settings. It has been demonstrated that recalibration is unnecessary for at least 8 hours (Pittman et al., Aronson et al., and Jonas et al., unpublished data) [3,4].The LiDCO? system provides a bolus indicator dilution method for measuring cardiac output and calibration of PulseCO?. A small dose of lithium chloride is injected via a central or p
Lack of agreement between bioimpedance and continuous thermodilution measurement of cardiac output in intensive care unit patients
Ben N Barry, Abhiram Mallick, Andrew R Bodenham, Michael Vucevic
Critical Care , 1997, DOI: 10.1186/cc106
Abstract: A total of 2390 paired data points from seven patients were collected. There was no correlation (r2 = 0.01) between the methods. The precision (1.16 l/min/m2) of agreement between the Vigilance and the Bomed, assessed by the Bland-Altam method, was very poor although the bias (-0.16 l/min/m2) appeared fair.The Bomed NCCOM 3 bioimpedance monitor shows poor agreement with the Baxter Vigilance continuous thermodilution monitor in a group of general ICU patients and cannot be recommended for cardiac output monitoring in this situation.The fluid bolus thermodilution method of cardiac output measurement, using a pulmonary artery catheter (PAC), has gained wide acceptance over the past 25 years. The advantages and disadvantages of the use of this method of monitoring critically ill patients are well established [1].A recent development has been the introduction of 'continuous' cardiac output monitoring using a modified PAC (Continuous Cardiac Output/SvO2 Catheter model 746H8F, Baxter Healthcare Corporation, Round Lake, Illinois, USA). This catheter has a thermal filament that produces pulses of heat at the level of the right ventricle, and a thermistor at the tip in the pulmonary artery senses temperature change. A dedicated computer (Vigilance, Baxter Healthcare Corporation) is required, which updates calculated cardiac output every 30–60 s. This system has been previously investigated [2] and has shown a very strong correlation with both the 'gold standard' dye dilution technique (r2 = 0.91) and fluid bolus thermodilution (r2 = 0.97). It has also been evaluated specifically for use in critically ill patients [3] and in a bench model of pulmonary artery blood flow [4].Bioimpedance cardiography has been developed over the past 30 years as a noninvasive technique to measure cardiac output. Monitors such as the Bomed Noninvasive Computerized Cardiac Output Monitor (NCCOM 3, Bomed Medical Manufacturing Ltd, Cheshire, UK) are commercially available to measure cardiac output. H
Compara??o entre a medida contínua do débito cardíaco e por termodilui??o em bolus durante a revasculariza??o miocárdica sem circula??o extracorpórea
Kim, Sílvia M.;Oliveira, Sílvia D. S.;Fonseca, Ubirajara S.;Malbouisson, Luiz Marcelo Sá;Auler Júnior, José Otávio Costa;Carmona, Maria José Carvalho;
Revista Brasileira de Anestesiologia , 2004, DOI: 10.1590/S0034-70942004000300005
Abstract: background and objectives: off-pump cabg surgery is related to major and abrupt hemodynamic changes that may not be immediately detected by continuous cardiac output measurement (cco). this study aimed at comparing results of cardiac index measurement with pulmonary artery catheter (pac) with thermal filament (baxter edwards critical care, irvine, ca) versus standard bolus thermodilution method during distal coronary anastomosis. methods: participated in this study 10 patients undergoing off-pump cabg who were monitored with pac with thermal filament. measurements of cardiac index were obtained in four moments: at anesthetic induction with the chest still closed (m1), after sternotomy (m2), after heart stabilization with the octopus device (m3) and at distal anastomosis completion (m4). results: there has been significant cardiac index decrease (p < 0.05) during coronary anastomosis, detected when measurements were taken with bolus thermodilution method. cardiac index has varied 2.8 ± 0.7 to 2.3 ± 0.8 l.min.m-2 in the beginning and 2.5 ± 0.8 l.min.m-2 at the end of anastomosis. this variation was not detected by the continuous method (from 3 ± 0.6 to 3.2 ± 0.5 to 3.1 ± 0.6 l.min.m-2 during anastomosis). conclusions: cco measurement with pac was late in detecting acute hemodynamic changes due to changes in heart position during off-pump cabg.
Investigations concerning the application of the cross-correlation method in cardiac output measurements
Maciej Gawlikowski, Tadeusz Pustelny
BioMedical Engineering OnLine , 2012, DOI: 10.1186/1475-925x-11-24
Abstract: In 99.2% of the examined cases the extreme of the cross-correlation function was easy to be estimated by numerical algorithms. In 0,8% of the remaining cases (with a plateau region adjacent to the maximum point) numerical detection of the extreme was inaccurate. The typical unreliability of the investigated method amounted o 5.1% (9.8% in the worst case). Investigations performed on a physical model revealed that the unreliability of cardiac output measurements by means of the cross-correlation method is 3–5 times better than in the case of thermodilution.The performed investigations and theoretical analysis have shown, that the cross-correlation method may be applied in cardiac output measurements. This kind of measurements seems to be more accurate and disturbance-resistant than clinically applied thermodilution.
Hemodynamic changes acutely determined by primary PCI in STEMI patients evaluated with a minimally invasive method  [PDF]
Cristina Giglioli, Omar Tujjar, Emanuele Cecchi, Daniele Landi, Marco Chiostri, Serafina Valente, Giorgio Jacopo Baldereschi, Francesco Meucci, Gian Franco Gensini, Salvatore Mario Romano
World Journal of Cardiovascular Diseases (WJCD) , 2013, DOI: 10.4236/wjcd.2013.34A010
Abstract: Objective: Few studies are available on the hemodynamic changes acutely determined by Primary Percutaneous Coronary Intervention (PCI) in ST-Elevation Myocardial Infarction (STEMI) patients, probably for the difficult evaluation of hemodynamic variables in this acute setting. Therefore, the paper is to evaluate the variations of several hemodynamic parameters determined by PCI using PRAM (Pressure Recording Analytical Method), minimally invasive hemodynamic monitoring. Methods: We analyzed in 20 STEMI patients submitted to PCI several hemodynamic variables, assessed with PRAM from radial/ femoral artery, 3-minute before PCI and at endprocedure. Variables measures were: systolic, diastolic, dicrotic and mean arterial pressures; heart rate (HR); stroke volume (SV); systemic vascular resistance (SVR); dP/dtmax; cardiac cycle efficiency (CCE). Results: In our patients HR, SVR and dP/dtmax decreased significantly (85 ± 6.3 to 77 ± 4.5, p = 0.002; 1738 ± 241 to 1450 ± 253, p = 0.022; 1.22 ± 0.11 to 1.11 ± 0.12, p = 0.007, respectively) while CCE and SV increased significantly (?0.25 ± 0.23 to ?0.01 ± 0.12, p < 0.001; 53 ± 8.4 to 65 ± 11.2, p < 0.001, respectively). Conclusions: Hemodynamic monitoring with PRAM seems feasible during primary PCI and can provide further notions regarding the acute effects determined on cardiovascular system by the culprit artery revascularization. The most significant hemodynamic changes acutely observed in our study should be mainly ascribed to the reduction in sympathetic activity after PCI with a rapid improvement of the cardiovascular system efficiency.

Débito cardíaco diminuído: revis?o sistemática das características definidoras
Souza, Vanessa de;Zeitoun, Sandra Salloum;Barros, Alba Lucia Bottura Leite de;
Acta Paulista de Enfermagem , 2011, DOI: 10.1590/S0103-21002011000100017
Abstract: objectives: to characterize the scientific articles related to the nanda-i nursing diagnosis, decreased cardiac output. verify those articles that describe the behavior of the defining characteristics of this diagnosis, identifying those that occur with the highest frequency. methods: a systematic review of literature published between the years 1985 - 2008 was conducted, using the following databases: lilacs, scielo, embase, medline, pubmed and cochrane. results: the sample included 13 articles which identified 50 defining characteristics. ten characteristics were noted to occur with high frequency: altered heart rate/rhythm, dyspnea, labile blood pressure, rales, oliguria / anuria, edema, cold skin, fatigue / weakness, decreased peripheral pulses and decreased peripheral perfusion. conclusion: this subject has not been explored in depth in the literature. the importance of physical examination, the use of less invasive techniques, and the need to review the proposed defining characteristics to provide clarity and objectivity in the identification of this nursing diagnosis was identified
Estimación del gasto cardíaco: Utilidad en la práctica clínica. Monitorización disponible invasiva y no invasiva
García,X.; Mateu,L.; Maynar,J.; Mercadal,J.; Ochagavía,A.; Ferrandiz,A.;
Medicina Intensiva , 2011,
Abstract: this aim of this review is to provide a detailed review of the physiologic conditions and variables of the cardiac output, as well as review the different techniques available for its measurement. we also want to establish the clinical situations in which the measurement of cardiac output can add valuable information for the management of critically ill patients. the fick technique, used in the beginning to calculate cardiac output, has been replaced today by thermodilution techniques (transcardiac or transpulmonary), lithium dilution, bioreactance, doppler technique or echocardiography. pulse wave analysis allows a continuous minimally invasive cardiac output measurement. other methods, such bioreactance, doppler technique or echocardiography currently provide a valid, fast and non-invasive measurement of cardiac output.
Comparison of the reproducibility of 2D doppler and 3D STIC in the measurement of fetal cardiac output  [PDF]
Rajeswari Parasuraman, Clive Osmond, David T. Howe
Open Journal of Obstetrics and Gynecology (OJOG) , 2011, DOI: 10.4236/ojog.2011.14031
Abstract: Objectives: Two methods have been described to assess fetal cardiac output (CO). It has usually been calculated by using 2D ultrasound to measure the diameter of outflow valves and Doppler ultrasound to measure flow velocity through the valves. Recently CO has been assessed using 3D spatio-temporal image correlation (STIC) to measure stroke volume. We aimed to compare the reproducibility of these techniques. Methods: In 27 women with singleton pregnancies, examinations were performed in three gestational age groups: 13 - 15, 19 - 21 and >30 weeks of gestation. Each mother was scanned once. Using 2D pulsed wave Doppler the duration of flow and average flow velocity in systole were measured through aortic and pulmonary valves. We averaged values from three consecutive Doppler complexes. The outlet valve diameters were measured and the cardiac output was calculated for each valve. The measurements were repeated to assess reproducibility. In the same women, we acquired STIC volumes of the fetal heart. The volume measurements were made using the 3D Slice method by one observer. Using 2 mm slices the circumference of the ventricles was traced at the end of systole and diastole to calculate ventricular volume before and after contractions to calculate stroke volume and hence cardiac output. The measurements were repeated to assess reproducibility. Results: The root mean square difference of log (CO) of repeat measurements ranged between 0.12 and 0.21 using Doppler compared to 0.7 to 1.47 using STIC. The differences in reproducibility reached statistical significance for both sides of the heart at all but one gestation. Conclusions: We found that Doppler assessment of fetal cardiac output was more reproducible than measurement using STIC.
Validation of a Novel Method for Cardiac Output Estimation by CT Coronary Angiography  [PDF]
Hetal H. Mehta, Brian G. Choi, Raman S. Dusaj, Amr Mohsen, Chunlei Liang, Jannet F. Lewis, Robert K. Zeman, Reza Sanai
Advances in Computed Tomography (ACT) , 2012, DOI: 10.4236/act.2012.12003
Abstract: Background: Cardiac output can be estimated during retrospectively gated CT coronary angiography by anatomically determining left ventricular volumes; prospective triggering to minimize radiation precludes this methodology. We propose an alternative method for cardiac output estimation based on preclinical models suggesting that cardiac output may be inversely related to contrast washout from the aortic root during timing bolus scanning, as measured by peak aortic root contrast attenuation. Methods: 34 patients had CT coronary angiography timing bolus performed with 20 ml iodixanol at 5.5 ml/s followed by 20 ml normal saline at 5.5 ml/s through an 18-Ga antecubital catheter. Peak aortic root contrast attenuation was correlated to cardiac output calculated by echocardiography using heart rate stroke volume from biplane Simpson’s method.Results: Mean age was 58 ± 13 years; body surface area, 2.0 ± 0.5 m2. 53% were women. Stroke volume, cardiac output and cardiac index were 67 ± 19 ml, 4.5 ± 1.6 L/min, and 2.2 ± 0.7 L/min/m2, respectively. Peak aortic root contrast attenuation was 207 ± 46 HU and correlated to cardiac output and cardiac index with r = –0.64, p < 0.0001 and r = –0.55, p < 0.001, respectively. Regression analysis estimates cardiac output = –0.02 peak aortic root contrast attenuation +9.1. Conclusion: This novel method for cardiac output estimation by CTCA appears feasible. The CT physiologic parameters using the timing test-bolus data moderately correlated with echocardiographic assessment of cardiac output. The calculation of cardiac output adds important hemodynamic data to anatomic information provided by CTCA, and further development of this method may preserve assessment of left ventricular performance in prospective triggering.
Correlation of Electric Cardiometry and Continuous Thermodilution Cardiac Output Monitoring Systems  [PDF]
Vishwas Malik, Arun Subramanian, Sandeep Chauhan, Milind Hote
World Journal of Cardiovascular Surgery (WJCS) , 2014, DOI: 10.4236/wjcs.2014.47016

Purpose: Impedance Cardiography (ICG) with its drawbacks to reliably estimate cardiac output (CO) when compared to reference methods has led to the development of a novel technique called Electrical Cardiometry (EC). The purpose of this study was to compare EC-CO with the Continuous CO (CCO) derived from Pulmonary Artery Catheter (PAC). Methods: 60 patients scheduled to undergo coronary artery surgery necessitating the placement of PAC were studied in the operating room. Standard ECG electrodes were used for EC-CO measurements. Simultaneous CO measurement from EC and PAC was done at three predefined time points and were correlated. Results: A significant high correlation was found between the EC-CO and CCO at the three time points. Bland and Altman analysis revealed a bias of 0.08 L/min, a precision of 0.15 L/min, with a narrow limit of agreement (-0.13 to 0.28 L/min). The percentage error between the methods was 3.59%. Conclusion: The agreement between EC-CO and CCO is clinically acceptable and these two techniques can be used interchangeably. Mediastinal opening has no effect on the correlation between these two modalities.

Page 1 /8934
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.