Remifentanyl vs Fentanyl impact on Ejection Fraction and Troponin in off pump cardiac surgery

Background: Patients undergoing cardiac surgery are at risk of postcardiotomy myocardial dysfunction. This condition causes delayed recovery, organ failure, prolonged intensive care unit and hospital stays, and an increased risk of mortality; these patients often require inotropic agent support. Levosimendan is a calcium sensitizer with a unique mechanism of action, binding to cardiac troponin C and enhancing myofilament responsiveness to calcium, increasing myocardial contraction without increasing myocardial oxygen consumption. Phosphodiesterase III inhibitors such as milrinone provide an alternative means of inotropic support by increasing the concentration of cyclic AMP and intracellular calcium. They also have vasodilatory effects. Objective: The aim of this study was the comparison between levosimendan versus milrinone regarding their effects on the hemodynamics, need for additional mechanical (intra aortic balloon pump) or pharmacological support to the heart, weaning from mechanical ventilation and duration of intensive care unit stay for patients after Off-Pump Coronary Artery Bypass Graft (OPCABG) surgery suffering from impaired left ventricular function (preoperative ejection fraction ≤ 40%). Methods: 60 patients between 40 and 70 years of both sexes with impaired left ventricular function (ejection fraction ≤ 40%), New York Heart Association (NYHA III & IV), undergoing elective Off-Pump Coronary Artery Bypass Graft (OPCABG) surgery were selected for this study. After induction of anesthesia, patients were randomly assigned to one of two equal groups each containing 30 patients: Group L (Levosimendan group) included patients who received levosimendan 0.1- 0.2 µg/kg/min. Started immediately with the induction of anesthesia. Group M (Milrinone group) included patients who received milrinone 0.4-0.6 µg/kg/min. Started immediately with the induction of anesthesia. In both groups, norepinephrine was titrated (8 mg norepinephrine in 50 ml saline) to keep mean arterial pressure MAP ≥ 70 mmHg. Hemodynamic findings included Preoperative and post ICU discharge ejection fraction, systemic and pulmonary artery pressures, systemic and pulmonary vascular resistance, cardiac output and stroke volume. Also laboratory findings included Serum lactate and Troponin I., in addition, to post operative findings were: Need for intra aortic balloon pump, time of weaning from the ventilator, days of ICU stay and appearance of drug allergy compared in both groups. Results: There was a significant increase in the ejection fraction in both groups that was greater in the levosimendan group. The decrease in pulmonary pressure in the levosimendan group was more significant than milrinone group. There was a gradual decrease in pulmonary and systemic vascular resistance in both groups with a more significant decrease in the levosimendan group. There was a gradual increase in cardiac output and stroke volume in both groups that was greater in the levosimendan group. Serum lactate gradually decreased in both groups with an insignificant difference; there was an increase in serum troponin I level in both groups which was more significant in the milrinone group. Weaning from mechanical ventilation and length of ICU stay was shown to be significantly shorter in time in the levosimendan group. Conclusion: Both levosimendan and milrinone caused a significant increase in cardiac output, stroke volume and ejection fraction, with a decrease in pulmonary and systemic vascular resistance. These effects improved cardiac performance by decreasing afterload and increasing cardiac inotropism. It was noticed that these effects were more significant with levosimendan than milrinone. Also, there was a decrease in ICU stay, mechanical ventilation timing and hospital stay with levosimendan than milrinone which decreased the costs of treatment for the patients.

Background: Patients undergoing elective off-pump coronary artery bypass grafting (CABG) are at risk of hemodynamic instability, ischemia, arrhythmia, and dysfunction. These events need to be managed by pharmacological supports or relieving of mechanical obstruction (octopus) of the heart to maintain the hemodynamic stability. There is a paucity of data on the effect of left ventricular (LV) dysfunction on left atrial appendage (LAA) emptying velocity. We evaluated the relationship between LV function and LAA emptying velocity and requirement of inotropic support perioperatively. Materials and Methods: In this prospective open-label all-comer study, fifty patients undergoing elective off-pump CABG under general anesthesia, we measured LAA emptying velocity by pulsed wave Doppler and evaluated if it could predict the need for inotropes perioperatively. It is a case series of 50 patients without a comparator arm. We measured pulsed wave Doppler across the mitral valve leaflet and early mitral inflow velocity (Evel) and late mitral inflow velocity, tissue Doppler at the lateral annulus of the mitral valve (e’) and also calculated the ratio of Evel and e’. Need for inotrope in the intraoperative and postoperative period was captured perioperatively. Vasoactive-inotropic score (VIS) was calculated for all the patients. Results: The VIS was significant (P < 0.0001, with odds ratio of 131.6 and confidence interval of 95% (0.9–1). However, there was no significant correlation between ejection fraction (EF) and VIS (P = 0.87). In patients with the need of inotropes, LAA emptying velocity was significantly increased in the postgrafting period as compared to the pregrafting period (75.64 cm/s vs. 57.9 cm/s, P < 0.001). Conclusion: The assessment of LAA emptying velocity value was a useful predictor of the need of inotropic support during off-pump surgery, especially during Obtuse marginal and Ramus grafting. This study paves the need of larger case–control studies to validate the findings.

Efficacy of Perioperative Oral Triiodothyronine Replacement Therapy in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting

The ratio of early transmitral flow velocity to early diastolic velocity of the mitral annulus (E/e') correlates with left ventricular (LV) filling pressure. In particular, an E/e' ratio more than 15 is an excellent predictor of increased LV filling pressure. The authors evaluated the prognostic implications of preoperative estimated LV filling pressure, assessed by E/e' ratio, in patients undergoing off-pump coronary artery bypass graft surgery. This observational study investigated 1,048 consecutive adults undergoing elective off-pump coronary artery bypass graft surgery. The primary outcome was occurrence of major adverse cardiac events (MACE), defined as a composite of death, myocardial infarction, malignant ventricular arrhythmia, cardiac dysfunction, or need for new revascularization. Logistic regression and survival analyses were performed. An E/e' ratio more than 15 was independently associated with 30-day MACE (odds ratio 2.4, 95% CI 1.4-3.9, P = 0.001) and 1-yr MACE (hazard ratio 2.1, 95% CI 1.4-3.1, P = 0.001), irrespective of underlying LV ejection fraction. MACE free 1-yr survival rate was significantly decreased in patients with E/e' >15, irrespective of underlying LV ejection fraction. Increased LV filling pressure, assessed by E/e' ratio, is an independent predictor of 30-day and 1-yr MACE in patients who undergo elective off-pump coronary artery bypass graft surgery. These findings indicate that measurements of E/e' may assist in preoperative risk stratification of these patients.

Lee, Eun-Ho; Yun, Sung-Cheol; Chin, Ji-Hyun; Choi, Dae-Kee; Son, Hyo-Jung; Kim, Wook-Chong; Choi, Seong-Soo; Song, Jun-Gol; Hahm, Kyung-Don; Sim, Ji-Yeon; Choi, In-Cheol Author Information

Combination of Intrathecal Morphine and Remifentanil Infusion for Fast-Track Anesthesia in Off-Pump Coronary Artery Bypass Surgery

ABSTRACTBackground:Prophylactic use of intra-aortic balloon pump (IABP) mainly depends on left ventricular (LV) systolic function. Global longitudinal strain (GLS) is a robust prognostic parameter for LV strain. It has proved to be more sensitive than LV ejection fraction (EF) as a measure of LV systolic function and is a strong predictor of outcome.Aim:To determine whether GLS can be used as a reliable marker and its cut-off value for IABP insertion in patients undergoing elective off-pump coronary artery bypass grafting (OPCABG).Settings and Design:A prospective observational clinical study which included 100 adult patients scheduled for elective OPCABG.Materials and Methods:Two-dimensional (2D) speckle tracking echocardiography (STE)-estimated GLS was computed and compared with LV EF measured by three dimensional (3D) echocardiography for the insertion of IABP. The intensive care unit (ICU) parameters were correlated with echocardiographic parameters to predict early post-operative outcome.Results:IABP insertion correlates better with GLS (post-revascularization > pre-revascularization) than with 3D LV EF. Receiver operating characteristic (ROC) curve analysis revealed the highest area under the curve (AUC, 0.972) with a cut-off value of > -9.8% for GLS compared to 3D LV EF (AUC, 0.938) with a cut-off value of ≤ 44%. ICU parameters show better correlation with E/e’> GLS > WMSI than 3D LV EF.Conclusion:GLS is a better predictor of IABP insertion compared to 3D LV EF in patients undergoing OPCABG.

Red Blood Cell Transfusion Is Associated With Troponin Release After Elective Off-Pump Coronary Artery Bypass Surgery

COMPARISON OF GLOBAL LONGITUDINAL STRAIN WITH LEFT VENTRICULAR EJECTION FRACTION AS A PREDICTOR FOR IABP INSERTION IN PATIENTS UNDERGOING OFF-PUMP CORONARY ARTERY BYPASS GRAFTING: A PILOT STUDY

Relation between mixed venous oxygen saturation and cerebral oxygen saturation measured by absolute and relative near-infrared spectroscopy during off-pump coronary artery bypass grafting

To examine the effect of landiolol on cerebral blood flow in patients with normal or deteriorated cardiac function. Thirty adult patients who were diagnosed with angina pectoris and who underwent elective off-pump coronary artery bypass surgery were studied. Patients were divided into two groups, one with a preoperative left ventricular ejection fraction (EF) of 50% or higher (normal EF group; n = 15) and the other with an EF of less than 50% (low EF group; n = 15). The mean cerebral blood flow velocity (Vmca) and pulsatility index (PI) in the middle cerebral artery were recorded using transcranial Doppler ultrasonography (TCD). Individual hemodynamic data were obtained using a pulmonary arterial catheter. In both groups, landiolol produced a significant decrease in heart rate (HR), which then returned to baseline 15 min after administration was completed. A significant decrease in mean arterial pressure occurred in the low EF group, but the decrease was within 30% of the baseline. In the normal EF group, there was no decrease in cardiac index (CI), whereas in the low EF group, CI significantly decreased along with the decrease in HR. There were no significant differences in Vmca and PI between the two groups. Continuous administration of landiolol at a dose of 0.04 mg/kg/min after 1 min rapid i.v. administration at a dose of 0.125 mg/kg/min decreases HR without causing aggravation of CBF during treatment of intraoperative tachycardia in patients with normal and deteriorated cardiac function.

Off-pump coronary artery bypass grafting provides complete revascularization with reduced myocardial injury, transfusion requirements, and length of stay: A prospective randomized comparison of two hundred unselected patients undergoing off-pump versus conventional coronary artery bypass grafting

Background:Cardiosurgical patients can be often anemic, and preoperative anaemia is associated with increased postoperative complications, as well as morbidity and mortality.Objective:The present study was conducted aiming to determine the influence of lower preoperative hematocrit values on the early postoperative recovery of patients undergoing elective off-pump coronary artery bypass grafting (OPCABG).Methods:Our retrospective study included 150 patients who underwent elective OPCABG surgery from September 2021 to December 2022 at the Clinic for Cardiovascular Surgery University of Sarajevo. Patients were divided into two groups, anemic and non-anemic, with anemia defined as hemoglobin level <130g/l males and <120g/l females. Study observed comorbidities and early postoperative data.Results:Overall prevalence of anemia in OPCABG patients was 36,6%, more frequent among older patients. Comorbidities as chronic obstructive pulmonary disease, hypertension, ejection fraction was quite similar in both groups, but body mass index was significantly higher in the group of patients with anemia (29.9% vs 28.4%). In early recovery period, vasopressors were more used in patients with anemia (63.6% vs 42.1%) and their doses were higher. Total drainage was higher in patients with anemia (744.45±45.72 ml vs 681.58±349.06 ml). Number of transfusions was higher in the group of patients with anemia: red blood cells (0.89±1.29 vs 0.29±0.84; p<0,05), fresh frozen plasma (0.65±1.13 vs 0.41±1.15; p<0,05) and platelets (0.11±0.57 vs 0,07±0.42; p>0,05). Duration of mechanical ventilation was longer in patients with anemia compared to non-anemic patients (623-91±259.83 minutes vs 469±191.13 minutes). Atrial fibrillation occurred more often in patients with anemia (12.7 vs 7.4%). Length of stay in the intensive care unit was without significant difference.Conclusion:Based on our findings, patients who underwent elective OPCABG with lower than normal hematocrit, needed more blood and blood products, more vasopressor drugs in higher doses, longer mechanical ventilation, all which can prolong the patient’s recovery and increase the cost of treatment.

Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk.

BackgroundThe heparin sensitivity index (HSI) is closely associated with perioperative ischemic events and increased blood loss in cardiac surgery. Previous studies have produced conflicting results. Therefore, this study aimed to investigate the relationship between HSI and postoperative blood loss specifically in Chinese patients undergoing elective off-pump coronary artery bypass grafting (OPCAB).MethodsPatients underwent OPCAB between March 2021 and July 2022 were retrospectively included. Enrolled patients were classified into Low-HSI (HSILOW; HSI < 1.3) and Normal-HSI (HSINORM; HSI ≥ 1.3) groups. HSI = [(activated clotting time (ACT) after heparin) – (baseline ACT)] / [loading dose of heparin (IU/kg)]. Primary outcome included postoperative blood loss at 24 h. Secondary outcomes were total postoperative blood loss, transfusion requirement of red blood cell (RBC), fresh frozen plasma (FFP), platelet concentrates (PC), and other complications.ResultsWe retrospectively analyzed 303 Chinese OPCAB patients. HSILOW group had higher preoperative platelet (PLT) count (221 × 109/L vs. 202 × 109/L; P = 0.041) and platelet crit (PCT) value (0.23% vs. 0.22%; P = 0.040) compared to HSINORM group. Two groups showed no significant differences in postoperative blood loss at 24 h (460 mL vs. 470 mL; P = 0.252), total blood loss (920 mL vs. 980 mL; P = 0.063), RBC transfusion requirement (3.4% vs. 3.1%; P = 1.000), FFP transfusion requirement (3.4% vs. 6.2%; P = 0.380), and other complications. Preoperative high PLT count was associated with low intraoperative HSI value (odds ratio: 1.006; 95% confidence interval: 1.002, 1.011; P = 0.008).ConclusionsIntraoperative HSI value was not associated with postoperative blood loss in Chinese patients undergoing OPCAB. Preoperative high PLT count was an independent predictor of low intraoperative HSI value.