The effects of on-pump and off-pump coronary artery bypass surgery on oxidative stress and cerebral oxygenation: a prospective observational study.

Background/aim: In this prospective observational study, our goal was to investigate the relationship between serum levels of oxidative stress (OS) parameters and regional cerebral oxygen saturation (rSO2) in addition to evaluating postoperative clinical outcomes among patients undergoing coronary artery bypass graft surgery (CABG). Materials and methods: This study comprised 64 adult patients undergoing elective CABG (on-pump [n = 48] and off-pump [n = 16]) procedures. Serum OS levels and rSO2 values were measured intraoperatively at three specific time points: T1 (after induction), T2 (15 min before aortic cross-clamp removal or the final distal anastomosis), and T3 (15 min after aortic cross-clamp removal or the last distal anastomosis). Results: Serum OS and lactate values demonstrated higher levels at T2 and T3 (p < 0.001), while rSO2 values were lower at T2 (p = 0.024) in the on-pump CABG group compared to the off-pump CABG group. The rSO2 values at T2 exhibited a negative correlation with OS parameters, lactate levels at T2 and T3, aortic clamp time, postoperative mechanical ventilation time, and intensive care unit stay length. In the multivariate linear regression analysis (R2 = 0.181, p = 0.001), lactate values at T2 emerged as the sole factor affecting the OS index at T2 (t = 2.843, p = 0.006). Conclusion: In our study, we observed elevated OS values and relatively low rSO2 values during on-pump CABG procedures, with rSO2 showing an association with increased OS parameters. Close monitoring of the OS response level and rSO2 during CABG could potentially enhance postoperative clinical outcomes.

The Prognostic Value of Inflammatory Indices in Predicting Poor Postoperative Outcomes in Isolated Coronary Artery Bypass Graft Surgery.

BACKGROUND: This study aimed to analyze the predictive effect of various inflammatory indices and inflammatory biomarkers on prognosis after coronary artery bypass grafting (CABG). METHODS: In this retrospective observational study, data were recorded from 99 patients who underwent isolated elective CABG between January 2019 and June 2021 and met the inclusion criteria. The patients were divided into two main groups according to the postoperative clinical results: "favorable outcome" and "poor outcome." Preoperative inflammatory parameters, inflammatory indices (such as systemic inflammation index (SII), neutrophil/lymphocyte ratio (NLR), derived NLR (dNLR)), and clinical variables were compared between the groups. RESULTS: Poor postoperative outcomes developed in 31 (31.3%) patients. In the univariate analysis, white blood cell count (p=0.008), neutrophil count (p=0.002), SII (p=0.018), NLR (p=0.003), and dNLR (p=0.003) were found to be significant predictors for poor outcomes. In the multivariate analysis, only the presence of chronic obstructive pulmonary disease (COPD) (OR=8.765; 95% CI 1.308-58.702; p=0.025) and high creatinine levels (OR=1.049; 95% CI 1.005-1.094; p=0.027) were independent risk factors for poor outcomes. Optimal cut-off values were 603.08 (areas under the curve (AUC)=0.632, p=0.036) for SII, 2.34 (AUC=0.669, p=0.007) for NLR, and 1.76 (AUC=0.667, p=0.008) for dNLR. CONCLUSION: SII, NLR, dNLR, and inflammatory markers, such as white blood cell and neutrophil counts, are feasible markers for predicting poor outcomes following CABG procedures. These parameters may aid in the development of early therapeutic interventions to improve patient outcomes.

Early and Mid-Term Outcomes of Delayed Sternum Closure Strategy in Adult Cardiac Surgery: A Single-Center Experience.

BACKGROUND: Delayed sternum closure is a crucial strategy in the management of hemodynamic instability after weaning from cardiopulmonary bypass. This study aimed to evaluate our outcomes with this technique in light of the literature. METHODS: We retrospectively reviewed the data of all the patients who developed postcardiotomy hemodynamic compromise and intraaotic balloon pump was inserted between November 2014 to January 2022. Patients were divided into two groups: primary sternal closure group, and delayed sternum closure group. Patients' demographic data, hemodynamic parameters, and postoperative morbidities were recorded. RESULTS: Delayed sternum closure was performed in 16 patients with an incidence of 3.6%. The most common indication was hemodynamic instability in 14 patients (82%), followed by arrhythmia in 2 patients (12%) and diffuse bleeding in 1 patient (6%). The mean time to sternum closure was 21 (±7) hours. Three patients died (19%), p > 0.999. The median follow-up period was 25 months. Survival analysis revealed that the survival rate was 92%, p = 0.921. Deep sternal infection was observed in one patient with (6%), p > 0.999. multivariate logistic regression analysis revealed that end-diastolic diameter [odds ratio (OR) 4.5, 95% CI (1.19-17), p = 0.027], right ventricle diameter [OR 3.9, 95% CI (1.3-10.7), p = 0.012] and aortic clamp time [OR 1.16, 95% CI (1.02-1.12), p = 0.008] were independent risk factors for delayed sternum closure. CONCLUSIONS: Elective delayed sternal closure is a safe and effective method for treating postcardiotomy hemodynamic instability. It can be performed with a low incidence of mortality and sternal infections.

Association of preoperative plasma fibrinogen level with postoperative bleeding after on-pump coronary bypass surgery: does plasma fibrinogen level affect the amount of postoperative bleeding?

OBJECTIVES: Our primary aim was to investigate the association between the preoperative concentration of plasma fibrinogen and the volume of postoperative bleeding. Our secondary aim was to identify whether there is a possible correlation between the patients' different characteristics and haemostatic laboratory variables and the postoperative amount of bleeding after on-pump coronary artery bypass grafting procedures. METHODS: A total of 550 adult patients undergoing isolated coronary artery bypass grafting on cardiopulmonary bypass in our hospital were enrolled and investigated retrospectively. The total amount of chest tube drainage within the first 24 postoperative hours or until the patient was re-explored for bleeding was assessed. Excessive bleeding was defined as more than 500 ml drainage in the first 24 h. The patients were divided into 2 groups: Group 1: the patients who bled ≤500 ml in the first 24 h and Group 2: the patients who bled >500 ml in the first 24 h. RESULTS: A preoperative fibrinogen threshold associated with excessive bleeding was investigated by receiver operating characteristic curve analyses, revealing a calculated cutoff value of 3.1 g/l. Risk factors for increased bleeding were analysed by a logistic regression model that revealed male gender (P < 0.001), body mass index ≤28.3 kg/m2 (P < 0.001), platelet count ≤233 × 103/µl (P < 0.001), estimated glomerular filtration rate ≤90.8 ml/min (P < 0.001) and fibrinogen ≤3.1 g/l (P = 0.01) as significant predictors. CONCLUSIONS: A preoperative plasma fibrinogen concentration <3.1 g/l was associated with increased risk of excessive bleeding in patients undergoing on-pump coronary artery bypass grafting. The amount of postoperative blood loss can be roughly predicted with simple preoperative blood tests.