[Cardiac output. 1. Changes in cardiac output, organ blood flow and blood flow distribution ratio in endotoxin shock].
Explore the source record for details and available documents.
Animals↗
SEARCH · PubMed Health
Results for “CARDIAC OUTPUT”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
[Treatment of low cardiac output following extracorporeal circulation with captopril].
Seven patients in low-output cardiac failure, resistant to conventional vasodilators and inotropic agents, following surgery with extra-corporeal circulation were given oral captopril, an angiotensin converting enzyme inhibitor. The effects of captopril on haemodynamic and renal function were studied after 2, 6, 12 and 24 hours of treatment. After two hours, there was a mean reduction in systemic arterial resistance of 29%, in pulmonary arterial resistance of 18% and in pulmonary wedge pressure of 15%. The mean increase in the cardiac index was 28%. This marked initial haemodynamic improvement was either maintained or increased over the rest of the 24 hours. By 24 hours there had been a mean increase in urinary sodium excretion of 200%. The urinary sodium/potassium ratio increased from 0.62 to 1.45. Oral captopril thus seems suitable for treating low-output cardiac failure following surgery requiring extra-corporeal circulation.
Adult↗
Clinical evaluation of USCOM ultrasonic cardiac output monitor in cardiac surgical patients in intensive care unit.
BACKGROUND: The USCOM ultrasonic cardiac output monitor (USCOM Pty Ltd, Coffs Harbour, NSW, Australia) is a non-invasive device that determines cardiac output by continuous-wave Doppler ultrasound. The aim of this study was to evaluate the accuracy of the USCOM device compared with the thermodilution technique in intensive care patients who had just undergone cardiac surgery. METHODS: We conducted a prospective study in the 18-bed intensive care unit of a 600-bed tertiary referral hospital. Twenty-four mechanically ventilated patients were studied immediately following cardiac surgery. We evaluated the USCOM monitor by comparing its output with paired measurements obtained by the standard thermodilution technique using a pulmonary artery catheter. RESULTS: Forty paired measurements were obtained in 22 patients. We were unable to obtain an acceptable signal in the remaining two patients. Comparison of the two techniques showed a bias of 0.18 and limits of agreement of -1.43 to 1.78. The agreement may not be as good between techniques at higher cardiac output values. CONCLUSIONS: The USCOM monitor has a place in intensive care monitoring. It is accurate, rapid, safe, well-tolerated, non-invasive and cost-effective. The learning curve for skill acquisition is very short. However, during the learning phase the USCOM monitor measurements are rather 'operator dependent'. Its suitability for use in high and low cardiac output states requires further validation.
Adult↗
Pulse contour analysis for cardiac output monitoring in cardiac surgery for congenital heart disease.
UNLABELLED: Conventional methods of cardiac output monitoring using pulmonary artery catheters may not be feasible in patients with congenital heart disease because of patients' small size or aberrant anatomy. We studied the accuracy of a new device, which uses pulse contour analysis to measure continuous cardiac output, in children and adults undergoing congenital heart surgery. Sixteen patients, median ages 7 yr old, were included in this prospective study. One-hundred-ninety-one data points were obtained in the pre- and postcardiopulmonary bypass periods and in the first 12 h after intensive care unit admission. We evaluated the relationship between cardiac index (CI) derived from transpulmonary thermodilution (TDCI) and CI derived from pulse contour analysis (PCCI). Bias and limits of agreement between TDCI and PCCI over all time periods were 0.1 +/- 1.94, indicating a wide dispersion of the data. Coefficient of correlation (r) between the TDCI and PCCI was 0.7. Although in previous studies, PCCI has been suggested to be accurate in adult cardiac surgery, we found it to be less reliable in our study patients, even after shunt correction. The relationships of the volume and pressure based measures of preload, intrathoracic blood volume index (ITBI), and central venous pressure with CI were also investigated. After repair, correlation (r) between PCCI or TDCI and ITBI (0.56 and 0.71, respectively) was better than that between PCCI or TDCI and CVP (0.16 and 0.11, respectively), indicating greater validity of ITBI as a measure of preload. IMPLICATIONS: Our results suggest that the pulse contour analysis cardiac output (CO) monitoring in patients undergoing congenital heart surgery may not provide as accurate or reliable measures of CO as previously suggested. The volume-based variable of preload intrathoracic blood volume index (ITBI) has better correlation with cardiac index (CI) than the central venous pressure, suggesting that ITBI may be a better indicator of preload.
Adolescent↗
Cardiac output measurement during cardiac surgery: esophageal Doppler versus pulmonary artery catheter.
BACKGROUND: Bolus thermodilution cardiac output (BCO) measurement has been considered as the "gold standard" for cardiac output (CO) measurement. However, it requires placement of a pulmonary artery (PA) catheter, and questions have been raised regarding the risk/benefit ratio of this invasive technique. Furthermore, great variations between measurements have been reported. Continuous thermodilution CO (CCO) measurement is reported to be a better alternative, but it still requires the placement of a PA catheter. Esophageal echo-Doppler ultrasonography (ED) provides non-invasive continuous measurement of CO (ED-CO). This study was thus designed to compare the agreement between ED-CO and both thermodilution techniques (BCO and CCO). METHODS: Twenty-four patients undergoing primary coronary artery bypass graft surgery were randomized to have a PA catheter placed for measurement of either BCO or CCO. All patients also had an ED probe placed. In Group I patients (n = 12), BCO measurement was carried out every 15 minutes throughout the surgery except during cardiopulmonary bypass, with concurrent ED-CO reading recorded at the same time point. In Group II patients (n = 12), CCO and ED-CO measurements were recorded at the same designated points of time as in Group I. The agreement between methods (BCO vs. ED-CO or CCO vs. ED-CO) was assessed using Bland-Altman method. RESULTS: The range of measured CO of each method was 2.1 to 9.4 l/min for BCO, 2.4 to 9.2 l/min for CCO and 2.3 to 8.9 l/min for ED-CO. ED-CO and CCO had excellent agreement with a linear regression coefficient (r2 value) of 0.846, and a bias (mean difference) and SD of bias of 0.05 +/- 0.49 l/min. In contrast, the agreement between BCO and ED-CO was poorer; correlation was low (r2 value 0.406) and both the bias and SD of bias were high (0.11 +/- 1.12 l/min). Furthermore, BCO measurements had poor reproducibility, whereas both ED-CO and CCO measurements had good reproducibility. CONCLUSIONS: Esophageal echo-Doppler ultrasonography is a satisfactory alternative for cardiac output measurement because it gives a value in good agreement with CCO measurement. With significant between-measurement variations, the accuracy and precision of BCO are uncertain, and it should not be considered as the "gold standard".
Adult↗
Hemodynamic effects of rescue protocol hydrocortisone in neonates with low cardiac output syndrome after cardiac surgery.
OBJECTIVE: To assess the hemodynamic effects and safety of hydrocortisone in neonates with low cardiac output syndrome requiring high levels of inotropic support and fluid resuscitation after cardiac surgery. DESIGN: Retrospective chart review. SETTING: Fifteen-bed pediatric cardiovascular intensive care unit. PATIENTS: Twelve neonates with low cardiac output syndrome after cardiac surgery to whom hydrocortisone was administered according to one of two dosing regimens (100 mg/[m.day] for 2 days, 50 mg/[m.day] for 2 days, and 25 mg/[m.day] for 1 day or 100 mg/[m.day] for 1 day, 50 mg/[m.day] for 2 days, and 25 mg/[m.day] for 2 days) were identified from the Department of Pharmacy database between September 2002 and January 2004. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The mean and systolic blood pressure increased significantly 3 hrs after hydrocortisone treatment from the values preceding hydrocortisone administration. The mean blood pressure increased from 44.0+/-3.0 to 55.4+/-2.3 mm Hg (p=.01) and the systolic blood pressure increased from 64.2+/-4.7 to 78.3+/-3.4 mm Hg (p=.04). Comparable beneficial changes were also seen in the heart rate, which decreased from 168.3+/-4.6 to 148.3+/-5.6 beats/min (p=.004) after 24 hrs of hydrocortisone administration and remained at this level during the 72 hrs of follow-up. Significant weaning of epinephrine infusions was possible, from a mean dose of 0.16 to 0.06 microg/(kg.min) (p=.008), within 24 hrs after the initiation of steroid administration, and this reduction was not offset by increases in other inotropic agents. hydrocortisone administration caused nonsignificant increases in mean blood glucose concentration (from 116.2+/-20.6 to 156.0+/-25.6 mg/dL; p=.64), mean white blood cell count (from 16.6+/-1.6 to 18.9+/-2.6 x 10 U/L; p=.35), and sodium level (from 144.7+/-1.3 to 145.3+/-1.3 mmol/L; p=.51). Ten of the 12 patients (83.3%) survived. CONCLUSION: Most of the hemodynamically compromised neonates who were unresponsive to high doses of inotropic agents and fluid resuscitation after heart surgery responded to hydrocortisone with improvement of hemodynamic parameters and a decrease in inotropic requirements.
Anti-Inflammatory Agents↗
Comparison of a central and a peripheral (cephalic vein) injection site for the measurement of cardiac output using the lithium-dilution cardiac output technique in anesthetized dogs.
The objective of this study was to determine the agreement between cardiac output measured by central (cranial vena cava) versus peripheral (cephalic vein) venous injection of lithium chloride for lithium-dilution cardiac output (LiDCO) determination in the dog. Five dogs (2 males, 3 females), anesthetized with halothane, were used. With each dog, 12 alternating central and peripheral LiDCO measurements were made, resulting in 10 paired comparisons. A total of 50 comparisons were obtained, the cardiac output measurements ranging from 1.11 to 2.76 L/min. The LiDCO measurement from the cephalic vein was similar to that obtained from the recommended central venous site: the difference between the central and cephalic vein determinations for all measurements was 0.098+/-0.336 L/min (mean +/- 2 standard deviations). Linear regression analysis demonstrated a slope of 1.050 (95% confidence interval 0.904 to 1.196) and a y intercept of 0.005 (r = 0.902). Therefore, although the central venous site is recommended by the manufacturer, the cephalic vein can be used instead in the dog, eliminating the need for central venous catheterization and thus reducing time and expense.
Animals↗
Haemodynamic effects of different doses of dopexamine hydrochloride in low cardiac output states following cardiac surgery.
We studied the haemodynamic effects of dopexamine hydrochloride, a beta 2-adrenergic agonist with dopaminergic (DA1) activity, in 20 patients with low cardiac output following surgery for coronary artery bypass grafting and/or valve replacement or repair. Following titration of four doses (1, 2, 4 and 6 micrograms.kg-1.min-1), the dose producing the optimal response was infused for up to 48 h (five patients). During the infusion, significant increases in cardiac index and stroke volume were accompanied by significant decreases in systemic vascular resistance. Heart rate increased significantly up to 6 h and thereafter returned to control levels. Mean blood pressure was reduced but did not fall below 60 mmHg. However, in five patients treated for 48 h mean blood pressure had returned to control levels. Unwanted effects (tachycardia and hypotension) were seen chiefly at higher doses, leading us to conclude that infusion rates of 4 micrograms.kg-1.min-1 or less will be useful in the treatment of low cardiac output following cardiac surgery.
Adrenergic Agonists↗
Continuous versus intermittent cardiac output measurement in cardiac surgical patients undergoing hypothermic cardiopulmonary bypass.
OBJECTIVE: Continuous thermodilution cardiac output (CCO) measurement was clinically evaluated in patients who underwent coronary revascularization using hypothermic low-flow, low-pressure cardiopulmonary bypass (CPB). DESIGN: Prospective study. SETTING: University hospital setting. PARTICIPANTS: 30 cardiac surgical patients. INTERVENTIONS: CCO was correlated to standard bolus thermodilution cardiac output (ICO) obtained at end-expiration. MEASUREMENTS AND MAIN RESULTS: Measurements were taken at selected time points (n = 18) before anesthesia induction, before CPB, and 5 minutes to 12 hours after CPB. A total of 540 data pairs were thus obtained. ICO ranged from 1.9 to 9.9 L/min, CCO from 1.5 to 9.9 L/min. Correlation between ICO and CCO was highly significant (r = 0.872; p < 0.01), accompanied by an excellent accuracy (bias -0.0213 L) and precision (0.59 L) before CPB and more than 45 minutes after CPB. However, during the first 45 minutes after CPB, there was no correlation (r = 0.273) between ICO and CCO, and ICO tended to be relatively high, whereas CCO measurements showed relatively low values. During the first 45 minutes after hypothermic CPB, but not during the ensuing time period, central blood temperature decreased, which may be interpreted as a lack of thermal equilibration between central and peripheral compartments. It is hypothesized that thermal instability in combination with increased respiratory variations in pulmonary artery blood temperature caused inhomogenous rewarming of different body sites and might be the main reason for the lack of correlation between ICO and CCO. CONCLUSIONS: Despite an excellent correlation, accuracy, and precision between CCO and ICO before CPB and more than 45 minutes after hypothermic CPB, a lack of correlation in the early phase after CPB has been found. Further investigation is needed to elucidate the underlying cause of these findings and to clarify whether ICO or CCO or both fail to represent the real cardiac output up to 45 minutes after weaning from hypothermic CPB.
Adult↗
Lack of a critical cardiac output and critical systemic oxygen delivery during low cardiac output in the third trimester in the pregnant sheep.
OBJECTIVE: We sought to determine whether a critical cardiac output and oxygen delivery exist in normal pregnancy. We also sought to determine the role of fetoplacental oxygen demand on maternal oxygen transport variables in response to decreased maternal cardiac output. STUDY DESIGN: We studied 10 adult female sheep, 5 nonpregnant and 5 pregnant. We placed a flow-directed thermodilution catheter in the pulmonary artery and a balloon-tipped catheter in the right atrium of the sheep. We also placed a catheter for pressure monitoring and blood sampling in the descending thoracic aorta in both the mother and fetus. We decreased maternal cardiac output by incremental inflation of the right atrial balloon. We measured maternal cardiac output by intravenous bolus thermodilution technique. We also measured maternal and fetal acid-base status and serum lactate concentrations. We calculated a variety of maternal cardiorespiratory variables, including systemic oxygen delivery, systemic oxygen consumption, and fractional whole body tissue oxygen extraction. RESULT: The nonpregnant sheep displayed a critical cardiac output below which there was an abrupt decrease in oxygen consumption. In contrast, there was no critical level of cardiac output in the pregnant sheep. Maternal oxygen consumption was linearly dependent on cardiac output. Maximum fractional oxygen extraction was significantly lower in the pregnant sheep than in the nonpregnant sheep. CONCLUSION: States of low cardiac output in the pregnant sheep are associated with a lack of a critical cardiac output; the flow-dependent oxygen consumption observed is the result of either an impairment in tissue oxygen extraction or some degree of metabolic arrest or a combination of both. If this unique cardiac output-oxygen consumption relationship is seen in human pregnancy, it could have significant implications in the care of the critically ill obstetric patient.
Animals↗
Effects of iced and room temperature injectate on cardiac output measurements in critically ill patients with low and high cardiac outputs.
OBJECTIVE: To determine the effect of injectate temperature (iced or room temperature) on cardiac output values in critically ill adults with low and high cardiac outputs. DESIGN: Quasi-experimental. SETTINGS: Two multidisciplinary intensive care units in two large, metropolitan, private, nonprofit hospitals in Texas. SUBJECTS: A convenience sample of 21 critically ill men and women who averaged 61 years of age (range 31 to 82 years) and whose most recent cardiac output measured with room temperature injectate was low (< or = 3.5 L/min) or high (> or = 8.0 L/min). INTERVENTION: Iced injectate and room temperature injectate (randomly ordered) were used to measure cardiac output in each subject. OUTCOME MEASURES: Cardiac output value with iced injectate versus cardiac output value with room temperature injectate. RESULTS: We found significant differences between cardiac output measurements with room temperature and those with iced injectate in eleven critically ill patients with low cardiac outputs (< or = 3.5 L/min) and in ten critically ill patients with high cardiac outputs (> or = 8.0 L/min). In the low cardiac output group, cardiac outputs using room temperature injectate averaged 0.37 L/min (range 0.1 to 1.10 L/min) higher than cardiac outputs using iced injectate (p = 0.001). In the high cardiac output group, measurements with room temperature injectate averaged 1.17 L/min L/min (range 0.3 to 3.0 L/min) higher than cardiac outputs with iced injectate (p = 0.005). Percent differences between room temperature and iced injectate values averaged 13% (range 3% to 27%) in patients with low cardiac outputs and 11% (range 3% to 29%) in patients with high cardiac outputs. Seven (77%) of the patients in the low cardiac output group and four (40%) of the patients in the high cardiac group had a 10% or greater difference--which many clinicians describe as a clinically significant difference--between room temperature and iced injectate cardiac output values. CONCLUSION: Although research is clearly needed to substantiate these findings, we suggest that nurses use iced injectate in patients with low and high cardiac outputs (< or = 3.5 L/min or > or = 8.0 L/min) to ensure accurate measurement of cardiac output.
Adult↗
"In health and in a normoxic environment, VO2 max is/is not limited primarily by cardiac output and locomotor muscle blood flow".
Explore the source record for details and available documents.
Animals↗
Analysis of the accuracy of continuous thermodilution cardiac output measurement. Comparison with intermittent thermodilution and Fick cardiac output measurement.
OBJECTIVE: To evaluate the accuracy of cardiac output measurement obtained by a new continuous thermodilution cardiac output (CCO) pulmonary artery catheter compared to intermittent thermodilution (TCO) and the direct Fick method. DESIGN: Prospective open trial. SETTING: University hospital, intensive care unit. PATIENTS: 23 patients (15 surgical, 8 non-surgical) were monitored with the Intellicath pulmonary catheter. Cardiac output was evaluated by the three methods every 4 to 6h as long as the pulmonary artery catheter was necessary (8-96 h). RESULTS: The correlation coefficient between CCO and TCO was 0.92, no systematic bias was observed, and the relative error increased from 13.9% for a cardiac output of 21/min to 23.7% for an output of 101/min. When comparing CCO and Fick, the correlation coefficient was 0.89, no bias was detected, and the relative error increased from 20.4% for outputs of 21/min to 27.2% for outputs of 101/min. CONCLUSIONS: CCO provides clinically acceptable measurements. At high cardiac outputs, the difference with other methods increases and the results must be cautiously interpreted.
Bias↗
Transesophageal Doppler ultrasonography: evidence for improved cardiac output monitoring.
Cardiac output monitoring by transesophageal Doppler ultrasound has not gained wide clinical acceptance. A recently developed transesophageal Doppler device, Accucom 2, features technological advances aimed to reduce the error of this approach to the monitoring of cardiac output. To determine if Accucom 2 enables more accurate cardiac output monitoring, a prospective investigation was undertaken. Analyses of 923 simultaneous measurements of transesophageal Doppler and thermodilution cardiac output in 47 anesthetized patients were compared. Results using Accucom 2 were highly correlated with the results obtained with thermodilution (R = 0.91) and provided significantly greater accuracy in comparison with a previously developed Doppler cardiac output monitor, Accucom 1. Technological advances in transesophageal Doppler ultrasound hold promise for clinically useful noninvasive monitoring of cardiac output.
Aged↗
Oral administration of the dopamine prodrug docarpamine shortens need for drip infusion of dopamine in patients with low cardiac output syndrome after cardiac surgery.
BACKGROUND: Docarpamine (DOC) is a dopamine prodrug which can be orally administered. It has been found that oral docarpamine transforms into dopamine in vivo, and increases cardiac output and renal blood flow as effectively as intravenous dopamine. METHODS: We reviewed the records of 26 patients who had developed low cardiac output syndrome (LOS) after cardiac surgery and received docarpamine during the early postoperative course. Five patients discontinued docarpamine within 2 days due to arrhythmia. There were 3 hospital deaths. The remaining 18 patients were divided into two groups according to the timing of docarpamine administration. In group A docarpamine was administered during and after weaning from intravenous catecholamines, in group B only on demand after weaning from intravenous catecholamines. RESULTS: There were 12 patients in group A and 6 in group B, and the severity of LOS was relatively milder in group B than in group A. Stable hemodynamics and sufficient daily urinary output were maintained by oral administration of DOC in both groups just as well as by drip infusion of catecholamines. CONCLUSION: Sinse continuous drip infusion of catecholamine commonly slows recovery in LOS patients, it is considered that switching from drip infusion of catecholamines to oral DOC administration is safe and useful for earlier recovery in LOS patients after cardiac surgery.
Administration, Oral↗
Effect of bacteremia and fluid resuscitation on cardiac output.
The cardiac output acutely inducible by a 1-ml/kg/min saline infusion was observed in 12 septic and 7 nonseptic cynomolgus monkeys. In septic monkeys intravenous live E. coli were titrated to rapidly produce equivalent hypotension which was maintained for 1 hr before saline. Bacteria dose range was 1.3 X 10(11) bacteria/kg-400 X 10(11) bacteria/kg. There was no significant correlation between the dose of bacteria and the cardiac output nadir; however, the subsequent maximum cardiac output during saline resuscitation was significantly negatively correlated with the bacterial dose. In conclusion, widely varying amounts of intravenous bacteria can produce the same degree of hypotension and not correlate with cardiac output. In contrast, cardiac output measured early during subsequent saline resuscitation better predicts the severity of bacteremia.
Animals↗
Propofol and fentanyl anaesthesia for patients with low cardiac output state undergoing cardiac surgery: comparison with high-dose fentanyl anaesthesia.
We have compared the haemodynamic effects of an infusion of propofol 8 mg kg-1 h-1 followed by 4 mg kg-1 h-1 and fentanyl 15 micrograms kg-1 (group 1) with midazolam 3-6 mg and fentanyl 60 micrograms kg-1 (group 2) in patients with a low cardiac output state undergoing cardiac surgery. Heart rate was lower in group 1 throughout the period before cardiopulmonary bypass. There were no significant differences between the groups in other measured variables. Arterial pressure decreased in both groups after induction, by 21% in group 1 and 18% in group 2. Thermodilution assessment of right ventricular ejection fraction was unchanged. Myocardial contractility was not affected adversely. Patients in group 1 who received an infusion of propofol and a smaller dose of fentanyl awakened sooner and the trachea was extubated earlier.
Adult↗
[Comparison of enoximone and dobutamine treatment on cardiac output after cardiac surgery].
Explore the source record for details and available documents.
Cardiac Surgical Procedures↗