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Objectives: To measure the effects of fenoldopam mesylate infusion on splanchnic blood flow in patients undergoing myocardial revascularization with cardiopulmonary bypass., Design: An experimental observational study., Setting: A single-institution community hospital., Participants: Eighteen patients undergoing on-pump coronary artery bypass graft surgery., Interventions: Fenoldopam mesylate infusion (0.1 μg/kg/min)., Measurements and Main Results: Blood flow through the celiac artery, superior mesenteric artery, portal vein and hepatic artery were assessed by means of Doppler measurements. The main hemodynamic variables were measured using echocardiography. The infusion of fenoldopam significantly increased the blood flow through both celiac and superior mesenteric arteries by decreasing vascular resistance. The percentage of cardiac output directed to these 2 vessels increased significantly; the increase through the superior mesenteric artery was greater compared with the celiac artery. Portal vein and hepatic artery blood flow also consistently increased. No significant variations were observed with respect to hemodynamic variables., Conclusions: The infusion of fenoldopam increased the flow through the celiac artery and superior mesenteric artery; the effect was higher for the latter. These changes did not affect the hemodynamic variables., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Aim: The main indexes of ventricular function used in clinical practice are strongly influenced by the ventricular load conditions. Tissue Doppler imaging (TDI) has been reported to be a powerful modality that enables assessment of ventricular wall motion with a high temporal and spatial resolution. The study of the systolic movements of the mitral annulus has been proposed as a valid index of myocardial contractility. The aim of this study was to verify if the systolic movements of the mitral annulus by TDI are load-dependent in patients undergoing coronary artery bypass grafting. We evaluated the effect of load changes on systolic (S(M)) and isovolumic (S(IVC)) velocity waves, and on isovolumic acceleration (S(IVA))., Methods: Twenty-three patients undergoing coronary artery bypass grafting were evaluate. Load was changed with a rapid infusion of 7 cc/kg of a gelatin solution. The sample volume of TDI was placed at the lateral side of the mitral annulus in the mid-esophageal 4-chamber view., Results: The increase preload resulted in a statistically significant increase of S(M) (8.7+/-1.04 cm/s vs. 9.99+/-0.88 cm/s P=0.01), and a statistically significant increase of S(IVC) (5.65+/-1.95 cm/s vs. 6.75+/-1.53 cm/s P=0.03). S(IVA) does not appear to be changed after the increase of preload (203.45+/-45.69 cm/s(2) vs. 211.41+/-71.28 p=0.81)., Conclusion: Only S(IVA) seems to be an independent index of cardiac functionality in cardiac surgery patients and appears to be an optimum index in the clinical evaluation of these patients.

Background: The hypothesis that fenoldopam mesylate, by increasing renal flow, could reduce renal damage in patients undergoing cardiac surgery with cardiopulmonary bypass has gained great interest. The aim of the current study was to quantify the relationship of the increase of the renal blood flow as a function of the fenoldopam dose in these patients and to evaluate renal flow distribution within the renal parenchyma using Doppler., Methods: Twenty-five patients admitted to cardiac surgery have been enrolled. We used the Doppler technique to measure renal blood flow at the level of the renal, segmental, interlobar, and interlobular arteries. We calculated both the resistive and pulsatility indexes in all the renal segments. Moreover, we calculated echographically all the variables of preload, afterload, and cardiac index. Measurements were performed at baseline and after the infusion of fenoldopam mesylate at the doses of 0.05, 0.1, 0.2, and 0.3 microg x kg(-1) x min(-1)., Results: Fenoldopam infusion at doses more than 0.1 microg x kg(-1) x min(-1) significantly increases blood flow in all renal compartments, thus improving the resistive and pulsatility indexes starting at a dose of 0.1 microg x kg(-1) x min(-1). The highest renal flow increase is observed with 0.3 microg x kg(-1) x min(-1). Fenoldopam seems to increase the renal flow directed to the most external kidney areas. Systemic hemodynamically significant changes are observed only in patients receiving doses more than 0.1 microg x kg(-1) x min(-1)., Conclusions: In hemodynamically stable patients undergoing cardiac surgery with preserved renal function, fenoldopam shows a pharmacodynamic dose-dependent profile: it significantly increases renal flow and reduces the resistances of the renal circulation starting at a dose of 0.1 microg x kg(-1) x min(-1)., (2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Recent clinical and experimental data indicate that volatile anaesthetics may precondition myocardium against ischaemia and infarction. The present clinical trial was designed to verify the cardioprotective effects of desflurane in patients undergoing elective coronary artery bypass surgery. It was hypothesized that desflurane preconditioning would decrease postoperative release of troponin I and brain natriuretic peptide (NT-proBNP). Besides, we have hypothesized that desflurane preconditioning would preserve the myocardium from the dysfunction following cardioplegic arrest., Methods: Twenty-eight patients were randomly divided into two groups: Control group (14 patients) and Desflurane group (14 patients). In Desflurane group (DS) patients, preconditioning was elicited after the onset of cardiopulmonary bypass via a 5-min exposure to desflurane (2.5 minimum alveolar concentration), followed by a 10-min washout before aortic cross-clamping and cardioplegic arrest. The control group (C) patients underwent an equivalent period (15 min) of pre-arrest desflurane-free bypass. Haemodynamic measurements were obtained at six different times. The biochemistry markers of cellular damage and myocardial dysfunction (troponin I, NT-proBNP) were determined. Left ventricular (LV) function was assessed using tissue Doppler imaging (TDI) of mitral annulus. Two-factor repeated-measures analysis of variance was used to evaluate differences over time between groups for all parameters determined in plasma samples and for all TDI-derived variables., Results: After surgery, both the troponin I values (2.04+/-1.09 ng/ml vs 1.44+/-0.77 ng/ml, p<0.01 after 24h and 1.62+/-0.96 ng/ml vs 1.00+/-0.24 ng/ml, p<0.01 after 72 h respectively) and those of the NT-proBNP (2187+/-282.9 ng/l vs 885.4+/-117.35 ng/l, p<0.01 after 24h and 3097.9+/-226.2 vs 1393.6+/-312.07 ng/l, p<0.01 after 72 h respectively) were less in the desflurane-treated patients. The values of TDI of mitral annulus were constantly better in desflurane-treated patients., Conclusions: We can conclude that the use of desflurane in these patients provides a pharmacological preconditioning so as to reduce myocardial necrosis and improve the cardiac performance in the postoperative period.

Aim: Bypass surgery in high risk patients over the age of 75 results in increased mortality and morbidity, which may be also related to the cardiopulmonary bypass system., Methods: Using the propensity score analysis, we have selected two homogeneous groups of high-risk elderly patients undergoing coronary surgery: 41 patients operated with cardiopulmonary bypass- coronary artery bypass graft (CPB-CABG), and 78 patients operated without cardiopulmonary bypass (off-pump coronary artery bypass graft, OPCABG). All preoperative and operative variables were similar and outcomes were compared., Results: Perioperative mortality was higher in the patient group operated with CPB (12.2%) as compared to patients operated without CPB (1.3%, P = 0.01). Perioperative complications were more frequent in the CPB-CABG group. Logistic regression analysis showed that avoiding CPB was an independent protective factor for mortality and morbidity. Midterm survival, freedom from angina, freedom from reintervention, and Canadian Cardiovascular Society (CSS) class were comparable between the 2 groups., Conclusion: OPCABG is safe in the high risk elderly population and significantly reduces postoperative mortality and morbidity. There are no differences in midterm results between the 2 groups of patients in our study.