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Hemodynamic State (hemodynamic + state)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Bench to Bedside: Electrophysiologic and Clinical Principles of Noninvasive Hemodynamic Monitoring Using Impedance Cardiography

ACADEMIC EMERGENCY MEDICINE, Issue 6 2003
Richard L. Summers MD
Abstract The evaluation of the hemodynamic state of the severely ill patient is a common problem in emergency medicine. While conventional vital signs offer some insight into delineating the circulatory pathophysiology, it is often impossible to determine the true clinical state from an analysis of blood pressure and heart rate alone. Cardiac output measurements by thermodilution have been the criterion standard for the evaluation of hemodynamics. However, this technology is invasive, expensive, time-consuming, and impractical for most emergency department environments. Impedance cardiography (ICG) is a noninvasive method of obtaining continuous measurements of hemodynamic data such as cardiac output that requires little technical expertise. ICG technology was first developed by NASA in the 1960s and is based on the idea that the human thorax is electrically a nonhomogeneous, bulk conductor. Variation in the impedance to flow of a high-frequency, low-magnitude alternating current across the thorax results in the generation of a measured waveform from which stroke volume can be calculated by a modification of the pulse contour method. To adequately judge the possible role of this technology in the practice of emergency medicine, it is important to have a sufficient understanding of the basic scientific principles involved as well as the clinical validity and limitations of the technique. [source]

Mixed venous oxygen saturation is a prognostic marker after surgery for aortic stenosis

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2010
J. HOLM
Background: Adequate monitoring of the hemodynamic state is essential after cardiac surgery and is vital for medical decision making, particularly concerning hemodynamic management. Unfortunately, commonly used methods to assess the hemodynamic state are not well documented with regard to outcome. Mixed venous oxygen saturation (SvO2) was therefore investigated after cardiac surgery. Methods: Detailed data regarding mortality were available on all patients undergoing aortic valve replacement for isolated aortic stenosis during a 5-year period in the southeast region of Sweden (n=396). SvO2 was routinely measured on admission to the intensive care unit (ICU) and registered in a database. A receiver operating characteristics (ROC) analysis of SvO2 in relation to post-operative mortality related to cardiac failure and all-cause mortality within 30 days was performed. Results: The area under the curve (AUC) was 0.97 (95% CI 0.96,1.00) for mortality related to cardiac failure (P=0.001) and 0.76 (95% CI 0.53,0.99) for all-cause mortality (P=0.011). The best cutoff for mortality related to cardiac failure was SvO2 53.7%, with a sensitivity of 1.00 and a specificity of 0.94. The negative predictive value was 100%. The best cutoff for all-cause mortality was SvO2 58.1%, with a sensitivity of 0.75 and a specificity of 0.84. The negative predictive value was 99.4%. Post-operative morbidity was also markedly increased in patients with a low SvO2. Conclusion: SvO2, on admission to the ICU after surgery for aortic stenosis, demonstrated excellent sensitivity and specificity for post-operative mortality related to cardiac failure and a fairly good AUC for all-cause mortality, with an excellent negative predictive value. [source]

Strong relationship between NT-proXNP levels and cardiac output following cardiac surgery in neonates and infants

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010
T. BREUER
Background: NT-proXNP, a new natriuretic peptide analyte, incorporates information about the concentrations of both N-terminal pro-atrial and pro-brain natriuretic peptides (NT-proANP, NT-proBNP). We aimed to investigate whether NT-proXNP is a reliable indicator of the cardiac index (CI) and the hemodynamic state in neonates and infants undergoing an open heart surgery. Methods: We enrolled 26 children under the age of 1 year into this prospective study. All patients underwent an elective cardiac operation with cardiopulmonary bypass (CPB) to achieve complete biventricular repair. Peri-operative hemodynamic parameters were assessed by transpulmonary thermodilution and natriuretic peptide levels were recorded. Results: The NT-proXNP level correlated significantly with the simultaneously measured NT-proANP level (r=0.60, P<0.001), but more strongly with the NT-proBNP level (r=0.89, P<0.001) and the arithmetic sum of both (r=0.88, P<0.001). NT-proXNP had a strong correlation with CI (r=,0.85, P<0.001), the stroke volume index (r=,0.80, P<0.001) and the global ejection fraction (r=,0.67, P<0.009) throughout the post-operative period. Conventionally measured parameters such as heart rate, mean arterial pressure and pulse-pressure product exhibited weaker correlations with CI than NT-proXNP. Among laboratory values, creatinine levels correlated significantly with CI (r=,0.77, P<0.001) and NT-proXNP (r=0.76, P<0.001) during the post-operative period. A post-operative NT-proXNP level of 3079 pmol/l was diagnostic for CI <3 l/min/m2 with 89% sensitivity and 90% specificity (area under the curve: 0.91 ± 0.05). Conclusion: NT-proXNP is a good marker of cardiac output following pediatric cardiac surgery and might be a useful tool in the recognition of a low output state. [source]

KICG value, a reliable real-time estimator of graft function, accurately predicts outcomes in adult living-donor liver transplantation,

LIVER TRANSPLANTATION, Issue 4 2006
Tomohide Hori
Reliable monitoring enabling evaluation of graft function is crucial after living-donor liver transplantation (LDLT). A method to identify poor graft function at an early postoperative period would allow opportune intensive clinical management to bring about further improvements in LDLT outcomes. This study assessed the reliability of the indocyanine green (ICG) elimination rate constant (KICG) value as an estimator of graft function and determined the actual temporal changes of KICG after LDLT. KICG values were measured using a noninvasive method in 30 adult recipients up to 28 days after LDLT. The receptor index (LHL15) based on liver scintigraphy, and graft parenchymal damage score based on histopathological findings were evaluated after LDLT and correlated well with simultaneous KICG. Thus, KICG measured by noninvasive method was confirmed as accurately evaluating graft function. Changes of KICG after LDLT in recipients with good graft function were maintained, after some falls in the early periods, and had a significant difference compared with those for recipients without good graft function; moreover, there were already significant differences in KICG 24 hours after LDLT. Mean transit time reflecting systemic hemodynamics revealed that recipients without good outcomes fell into an unstable systemic hemodynamic state, and effective hepatic blood flow has a large influence on liver regeneration after LDLT. In conclusion, we suggested that KICG values can predict clinical outcomes at the early postoperative period after LDLT by sharply reflecting the influence of systemic dynamics on splanchnic circulation. Liver Transpl 12:605,613, 2006. © 2006 AASLD. [source]