Red Blood Cell Transfusion Guided by Hemoglobin Only or Integrating Perfusion Markers in Patients Undergoing Cardiac Surgery: A Systematic Review and Meta-Analysis With Trial Sequential Analysis

Fenoldopam for Renal Protection in Cardiac Surgery: Pharmacology, Clinical Applications, and Evolving Perspectives

This comprehensive review examines the role of Fenoldopam, a selective dopamine-1 receptor agonist, in preventing and treating acute kidney injury (AKI) during cardiac surgery. AKI remains a significant complication in cardiac surgery, associated with increased morbidity, mortality, and healthcare costs. The review explores Fenoldopam's pharmacological properties, mechanism of action, and clinical applications, synthesizing evidence from randomized controlled trials, meta-analyses, and observational studies. While some studies have shown promising results in improving renal function and reducing AKI incidence, others have failed to demonstrate significant benefits. The review discusses these conflicting findings, explores potential reasons for discrepancies, and identifies areas requiring further research. It also compares Fenoldopam to other renoprotective strategies, including dopamine, diuretics, and N-acetylcysteine. The safety profile of Fenoldopam, including common side effects and contraindications, is addressed. Current guidelines and recommendations for Fenoldopam use in cardiac surgery are presented, along with a cost-effectiveness analysis. The review concludes by outlining future research directions and potential new applications of Fenoldopam in cardiac surgery. By providing a thorough overview of the current state of knowledge, this review aims to facilitate informed decision-making for clinicians and researchers while highlighting areas for future investigation.

Platelet versus fresh frozen plasma transfusion for coagulopathy in cardiac surgery patients

BACKGROUND

Platelets (PLTS) and fresh frozen plasma (FFP) are often transfused in cardiac surgery patients for perioperative bleeding. Their relative effectiveness is unknown.

METHODS

We conducted an entropy-weighted retrospective cohort study using the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database. All adults undergoing cardiac surgery between 2005-2021 across 58 sites were included. The primary outcome was operative mortality.

RESULTS

Of 174,796 eligible patients, 15,360 (8.79%) received PLTS in the absence of FFP and 6,189 (3.54%) patients received FFP in the absence of PLTS. The median cumulative dose was 1 unit of pooled platelets (IQR 1 to 3) and 2 units of FFP (IQR 0 to 4) respectively. After entropy weighting to achieve balanced cohorts, FFP was associated with increased perioperative (Risk Ratio [RR], 1.63; 95% Confidence Interval [CI], 1.40 to 1.91; P<0.001) and 1-year (RR, 1.50; 95% CI, 1.32 to 1.71; P<0.001) mortality. FFP was associated with increased rates of 4-hour chest drain tube output (Adjusted mean difference in ml, 28.37; 95% CI, 19.35 to 37.38; P<0.001), AKI (RR, 1.13; 95% CI, 1.01 to 1.27; P = 0.033) and readmission to ICU (RR, 1.24; 95% CI, 1.09 to 1.42; P = 0.001).

CONCLUSION

In perioperative bleeding in cardiac surgery patient, platelets are associated with a relative mortality benefit over FFP. This information can be used by clinicians in their choice of procoagulant therapy in this setting.

Effects of albumin and crystalloid priming strategies on red blood cell transfusions in on-pump cardiac surgery: a network meta-analysis

BACKGROUND

In on-pump cardiac surgery, the albumin priming strategy could maintain colloid osmotic pressure better than crystalloid solutions and reduce excessive perioperative fluid balance. However, a high-quality meta-analysis is required to compare the safety of these approaches in perioperative red blood cell (RBC) transfusions. Owing to limited direct evidence, we conducted a network meta-analysis (NMA) to increase the pool of studies and provide indirect evidence.

METHODS

The pre-defined primary outcomes were intraoperative and the first 24 h postoperative RBC transfusion volume in units. The pre-defined secondary outcome was postoperative blood loss (the first 24 h). We reviewed all randomized controlled trials comparing albumin, crystalloid, and artificial colloid priming strategies. Studies that only displayed pre-defined outcomes could be included. A pairwise meta-analysis was performed on studies that directly compared the pre-defined outcomes between albumin and crystalloids. Additionally, a random-effects network meta-analysis (NMA) model was employed to generate indirect evidence for the pre-defined outcomes between albumin and crystalloids.

RESULTS

The literature search identified 830 studies,10 of which were included in the final analysis. Direct meta-analysis indicated that crystalloid priming significantly decreased total perioperative RBC transfusions (MD: -0.68U; 95%CI: -1.26, -0.09U; P = 0.02) and intraoperative RBC transfusions (MD: -0.20U; 95%CI: -0.39, -0.01U; P = 0.03) compared to albumin. Postoperative RBC transfusions showed a decreasing trend in the crystalloid group; however, the difference was not statistically significant. (MD: -0.16U; 95%CI: -0.45, 0.14U; P = 0.30). After including indirect evidence, the NMA results continued to demonstrate a higher RBC receiving with the albumin priming strategy compared to crystalloids, although the differences did not reach statistical significance. For postoperative blood loss, direct evidence showed no significant differences between albumin and crystalloid priming strategies. However, NMA evidence displayed that albumin exist higher probability of reducing postoperative blood loss than crystalloid.

CONCLUSION

Both direct and NMA evidence indicated that the albumin priming strategy resulted in more perioperative RBC transfusions than crystalloids. Considering the additional blood management burden, the application of an albumin-priming strategy in on-pump cardiac surgery still needs more consideration.