Halim Ulugöl

Comparative Effects of Hemodilutional Anemia and Transfusion during Cardiopulmonary Bypass on Acute Kidney Injury: A Prospective Randomized Study

AIM Acute kidney injury after cardiopulmonary bypass has been associated with dilutional anemia during surgery. We aimed both to explore if this relation is modulated by blood transfusion and to understand the postoperative contribution of protein oxidation. METHODS In this randomized prospective study, after ethics committee approval and informed consent, 30 patients undergoing first-time elective coronary artery bypass grafting (CABG) with hematocrit between 21% and 25% at any time during extracorporeal circulation (ECC) were randomly and equally allocated into two groups. Group I consisted of patients who received red blood cells (RBC) during ECC, while in Group II, patients did not receive any RBCs. Besides routine hemodynamic and biochemical parameters, markers of renal injury such as neutrophil gelatinase-associated lipocalin (NGAL), creatinine clearance, and protein oxidation parameters (advanced oxidative protein products [AOPP], total thiol [T-SH]) were determined in both groups. RESULTS (1) Both cardiovascular parameters (MAP, HR) and the hospitalization period of the transfused group were not significantly different compared to the non-transfused group (P > .05); (2) While urine NGAL level (P < .05) increased and GFR (P < .01) decreased in the transfused group compared to the preoperative period, there were no significant changes in respective parameters of the non-transfused group compared to preoperative period; (3) AOPP concentrations did not change compared to postoperative periods in both groups (P > .05). However, T-SH concentration showed a transient increased at postoperative hour 6 (P < .001 vs preoperative period) but normalized at postoperative hour 24 (P > .05 versus preoperative period). CONCLUSION These findings suggest that a hematocrit value over 21% during ECC is safe for renal functions. RBC transfusion just to increase hematocrit may be deleterious.

Correction of dilutional anemia induces renal dysfunction in diabetic patients undergoing coronary artery bypass grafting: a consequence of microcirculatory alterations?

BackgroundIn this study we aimed to evaluate the effects of dilutional anemia resulting from cardiopulmonary bypass (CPB) and its correction with red blood cell (RBC) transfusion on tissue oxygenation and renal function in diabetic patients undergoing coronary artery bypass grafting (CABG).Method70 diabetic patients who underwent elective CABG and whose hematocrit values had been between 24–28% at any time during CBP were prospectively randomized and equally allocated to two groups: patients who received RBC during CPB (group I, n = 35) vs. did not receive RBC during CPB (group II, n = 35). Besides routine hemodynamic and biochemical parameters, biomarkers of ischemia and renal injury such as ischemia modified albumin (IMA), protein oxidation parameters [advanced oxidative protein products (AOPP), total thiol (T-SH)], neutrophil gelatinase-associated lipocalin (NGAL) and estimated glomerular filtration rate (eGFR) were measured in both groups.ResultsIn group I, T-SH, NGAL and urea levels were found to be significantly increased postoperatively compared to preoperative measurements (p < 0.05). Also, postoperatively, NGAL, creatinine, aspartate aminotransferase and AOPP levels were higher in group I than group II (p < 0.05).ConclusionThe correction of anemia with RBC transfusion in diabetic patients undergoing CABG could increase the risk of renal injury. Further studies verifying the effects of blood transfusions at the microcirculatory level are needed to optimize the efficacy of transfusions.

Comparative Effects of Blood and Crystalloid Cardioplegia on Cellular Injury and Oxidative Stress in Cardiovascular Surgery

Purpose: The purpose of this study was to evaluate the effect of different cardioplegic solutions on endothelial integrity and oxidative stress in cardiovascular surgery. Methods: In this randomized prospective study, after ethics approval and informed consent, 60 surgical patients were included. Patients undergoing coronary bypass surgery were randomized into two groups as warm blood cardioplegia (n = 30) and cold crystalloid cardioplegia (n = 30) following the cross-clamping. Measurements were performed at three time points: before induction of anesthesia (T1), at admission to intensive care unit (ICU) (T2) and at the 24th postoperative hour (T3). Besides biochemical routine hemodynamic monitoring, patients were assessed for the sialic acid (SA), ischemic-modified albumin (IMA), advanced oxide protein products (AOPPs), total thiol (SH), and free hemoglobin (fHb) level. Results: Neither crystalloid nor blood cardioplegia led to significant changes in the AOPPs, T-SH, and SA level (p >0.05). Crystalloid cardioplegia, however, increased IMA level compared to both baseline (p <0.01) and blood cardioplegia group (p <0.05). fHb levels were transiently increased in both groups at the second-time point (p <0.001). fHb level was lower in the crystalloid group compared to that in the other group (p <0.05) at T2. Conclusion: Cardioplegia type creates similar effects on glycocalyx integrity. However, myocardial protection could be provided with warm blood cardioplegia.

Is the Nexfin finger cuff method for cardiac output measurement reliableduring coronary artery bypass grafting? A prospective comparison with the echocardiography and FloTrac/Vigileo methods.

BACKGROUND/AIM The aim of the current study was to assess the accuracy of cardiac output (CO) measurements obtained by the Nexfin finger cuff method as compared with the FloTrac/Vigileo and echocardiography methods in coronary artery bypass grafting (CABG) patients. MATERIALS AND METHODS First-time elective CABG patients were prospectively enrolled in this study and divided into three groups according to CO measurement method. CO measurements were performed simultaneously by three different contributors and were collected by the fourth one 24 h postoperative in the intensive care unit (ICU). Data were statistically analyzed. RESULTS Seventeen female and 13 male patients between 42 and 78 years of age (with a mean of 56 ± 4) were the subjects of this study. The mean CO measurements were 5.9 ± 1.4 L/min, 5.8 ± 1.1 L/min, and 6.0 ± 1.1 L/min for the Nexfin, FloTrac/Vigileo, and echocardiography methods, respectively (P > 0.05). The correlation values between Nexfin and FloTrac/Vigileo, Nexfin and echocardiography, and FloTrac/Vigileo and echocardiography were r = 0.445, r = 0.377, and r = 0.384, respectively (P < 0.05). CONCLUSION Nexfin yielded results comparable to those obtained with FloTrac/Vigileo and echocardiography for the postoperative CO assessment of CABG patients. Nexfin may be used in uncomplicated, hemodynamically stable patients in ICU as a reliable and totally noninvasive method of CO measurement.