Patient blood management in the cardiac surgical setting: An updated overview

Presurgical circulating platelet-derived microparticles level as a risk factor of blood transfusion in patients with valve heart disease undergoing cardiac surgery

BACKGROUND

Cell-derived microparticles (MPs) are membrane vesicles that have emerged as a potential biomarker for various diseases and their clinical complications. This study investigates the role of MPs as a risk factor for blood transfusion in patients with valve heart disease undergoing cardiac surgery.

METHODS

Forty adult patients undergoing heart valve surgery with cardiopulmonary bypass (CPB) were enrolled, and venous blood samples were collected prior to surgical incision. Plasma rich in MPs was prepared by double centrifugation, and the concentration of MPs was determined using the Bradford method. Flow cytometry analysis was performed to determine MPs count and phenotype. Patients were divided into "with transfusion" (n = 18) and "without transfusion" (n = 22) groups based on red blood cell (RBC) transfusion.

RESULTS

There was no significant difference in MPs concentration between the "with transfusion" and "without transfusion" groups. Although the count of preoperative platelet-derived MPs (PMPs), monocyte-derived MPs (MMPs), and red cell-derived MPs (RMPs) was higher in "without transfusion" group, these differences were not statistically significant. The preoperative PMPs count was negatively correlated with RBC transfusion (P = 0.005, r = -0.65). Multivariate logistic regression analysis revealed that the count of CD41+ PMPs, Hemoglobin (Hb), and RBC count were risk factors for RBC transfusion.

CONCLUSION

This study suggests that the presurgical levels of PMPs, Hb, and RBC count can serve as risk factors of RBC transfusion in patients with valve heart disease undergoing cardiac surgery. The findings provide insights into the potential use of MPs as biomarkers for blood transfusion prediction in cardiac surgery.

Turbulence in surgical suction heads as detected by MRI

BACKGROUND

Blood loss is common during surgical procedures, especially in open cardiac surgery. Allogenic blood transfusion is associated with increased morbidity and mortality. Blood conservation programs in cardiac surgery recommend re-transfusion of shed blood directly or after processing, as this decreases transfusion rates of allogenic blood. But aspiration of blood from the wound area is often associated with increased hemolysis, due to flow induced forces, mainly through development of turbulence.

METHODS

We evaluated magnetic resonance imaging (MRI) as a qualitative tool for detection of turbulence. MRI is sensitive to flow; this study uses velocity-compensated T1-weighted 3D MRI for turbulence detection in four geometrically different cardiotomy suction heads under comparable flow conditions (0-1250 mL/min).

RESULTS

Our standard control suction head Model A showed pronounced signs of turbulence at all flow rates measured, while turbulence was only detectable in our modified Models 1-3 at higher flow rates (Models 1 and 3) or not at all (Model 2).

CONCLUSIONS

The comparison of flow performance of surgical suction heads with different geometries via acceleration-sensitized 3D MRI revealed significant differences in turbulence development between our standard control Model A and the modified alternatives (Models 1-3). As flow conditions during measurement have been comparable, the specific geometry of the respective suction heads must have been the main factor responsible. The underlying mechanisms and causative factors can only be speculated about, but as other investigations have shown, hemolytic activity is positively associated with degree of turbulence. The turbulence data measured in this study correlate with data from other investigations about hemolysis induced by surgical suction heads. The experimental MRI technique used showed added value for further elucidating the underlying physical phenomena causing blood damage due to non-physiological flow.

A Narrative Review of Clinical Decision Support Systems for Perioperative Bleeding Management in Cardiac Surgery

Bleeding complications in patients undergoing cardiac surgery are common. The clinician must assimilate multiple sources of monitoring information, make rational decisions on the etiology of the bleeding, and then formulate a treatment strategy. Clinical decision support systems that acquire this information and present the data in an easily usable format may be useful tools to guide the physician in optimizing treatment strategies through adherence to evidence-based best practice guidelines. The authors present a narrative review of the literature and discuss how clinical decision support systems may be useful to the clinician.

Single shot of intravenous iron in cardiac surgery: The ICARUS study

BACKGROUND

Iron deficiency (ID), with or without anemia, is commonly observed among patients scheduled for cardiac surgery. We investigated if screening ID in the immediate preoperative period and treating ID patients regardless of anemia could reduce perioperative transfusion requirements.

METHODS

This is an observational single-center propensity score-matched study including candidates to elective cardiac surgery prospectively and retrospectively enrolled. Prospectively enrolled patients were screened for ID at hospital admission: if ferritin was ≤100 μg/L or ≤ 300 μg/L with transferrin saturation index ≤20% they received intravenous ferric carboxymaltose, B12-vitamin, and folic acid. A retrospective series of patients not screened for ID and matched for gender, type of surgery, BMI, Goudie transfusion risk score, hemoglobin level, and red blood cell (RBC) indices, served as controls. The primary outcome was the proportion of patients requiring ≤1 packed RBC (pRBC) unit within day 7 or discharge The main secondary outcomes were intraoperative and postoperative pRBC transfusions, duration of hospitalization, and cost-effectiveness of ID screening and treatment.

RESULTS

We included 479 prospective and 833 retrospective cases: 442 patients screened for ID and 442 matched controls with unknown iron status were analyzed. ID was observed in 196 patients (44.3%) and iron was administered 1 day (IQR 1-2) before surgery. Overall, 76.9% of patients in the prospective group and 69.7% of controls received ≤1 pRBC transfusion (p = 0.014). The risk for multiple transfusions was lower in patients screened for ID (OR 0.689, 95% CI 0.510-0.930). Despite similar Hb levels at day 7, patients in the prospective group received fewer postoperative pRBC transfusions (p < 0.001) and had a shorter hospital length of stay (p < 0.001). Globally, hospitalization costs were lower in patients screened and treated for ID.

CONCLUSIONS

Short-term pre-operative iron therapy is associated with a reduction in postoperative transfusions in anemic and non-anemic ID cardiac surgery patients and has a favorable impact on hospitalization costs.

CLINICAL TRIAL REGISTRATION

NCT04744181.

Effect of fibrinogen replacement therapy on bleeding outcomes and 1-year mortality in patients undergoing thoracic aortic surgery: a retrospective cohort study

PURPOSE

This study aimed to examine the effect of fibrinogen replacement therapy with cryoprecipitate or fibrinogen concentrate on bleeding outcomes and 1-year mortality in patients undergoing thoracic aortic surgery.

METHODS

We retrospectively studied 439 consecutive patients who underwent thoracic aortic surgery with cardiopulmonary bypass between January 1st, 2010 and December 31st, 2019 and identified patients who received cryoprecipitate or fibrinogen concentrate (the fibrinogen replacement group) and those who did not (the control group). Multivariate analyses were performed to examine the associations of fibrinogen replacement therapy with perioperative major bleeding (i.e., excessive hemorrhage or blood transfusion), re-exploration for bleeding, and 1-year mortality.

RESULTS

There were 285 patients in the fibrinogen replacement group who received 2.2 ± 1.0 g of concentrated fibrinogen amount and 154 patients in the control group. The incidence of major bleeding in the fibrinogen replacement group was less than that in the control group in patients with fibrinogen level < 150 mg/dL during cardiopulmonary bypass (49.7% versus 74.6%, p = 0.0007, multivariate odds ratio; 0.33, 95% confidence intervals; 0.12-0.91, p = 0.03), but not in patients with fibrinogen level ≥ 150 mg/dL (25.0% versus 29.6%, p = 0.51). No significant difference was found in re-exploration for bleeding (1.0% versus 1.3%, p = 1.00) or 1-year mortality (10.4% versus 5.3%, multivariate Cox proportional-hazard ratio; 1.03, 95% confidence intervals; 0.82-1.31, p = 0.74) between the fibrinogen replacement group and the control group.

CONCLUSIONS

The results of this study indicate that 2-3 g of fibrinogen replacement reduces the incidence of major bleeding in patients with hypofibrinogenemia during cardiopulmonary bypass in thoracic aortic surgery.

The Effect of Cell Salvage on Bleeding and Transfusion Needs in Cardiac Surgery

Introduction. Cell salvaging is well established in the blood management of cardiac patients, but there remain some concerns about its effects on perioperative bleeding and transfusion variables. This randomized controlled study investigated the potential effects of the centrifuged end-product on bleeding, transfusion rates, and other transfusion-related variables in adult cardiac surgery patients submitted to extracorporeal circulation. Materials and Methods. Patients were randomly chosen to receive (cell-salvage group, 99 patients) or not to receive (control group, 110 patients) the centrifuged product of a cell salvage apparatus. Bleeding and transfusion rates according to the universal definition of perioperative bleeding (UDPB) classification, postoperative hemoglobin, coagulation, and oxygenation indices were recorded and compared between the groups. Results. Both groups had almost identical bleeding and transfusion rates (median value: 2 units of red blood cells (RBC) and no units of fresh frozen plasma (FFP) and platelets (PLT) for both groups, $p>0.05$ ). Patients in the cell-salvage group presented slightly higher hemoglobin concentrations (10.6 ± 1.1 vs. 10.1 ± 1.7 g/dL, $p<0.05$ , respectively) and a tendency towards better oxygenation indices (PaO2/FiO2: 241 ± 94 vs. 207 ± 84, $p=0.013$ ) in the postoperative period albeit with a tendency for prolongation of prothrombin time (INR: 1.31 ± 0.18 vs. 1.26 ± 0.12, $p=0.008$ ). Conclusion. Within the study’s constraints, the perioperative use of the cell salvage concentrate does not seem to affect bleeding or transfusion variables, although it could probably ameliorate postoperative oxygenation in adult cardiac surgery patients. A tendency to promote coagulation disturbances was detected.

Perioperative Factor Concentrate Use is Associated With More Beneficial Outcomes and Reduced Complication Rates Compared With a Pure Blood Product-Based Strategy in Patients Undergoing Elective Cardiac Surgery: A Propensity Score-Matched Cohort Study

OBJECTIVE

The goal of this study was to compare factor concentrate (FC)-based and blood product-based hemostasis management of coagulopathy in cardiac surgical patients in terms of postoperative bleeding, required blood products, and outcome.

DESIGN

Retrospective, propensity score-matched analysis.

SETTING

Single, tertiary, academic medical center.

PARTICIPANTS

One hundred eighteen matched pairs of 433 consecutive patients scheduled for cardiac surgery in two isolated periods with distinct strategies of hemostasis management.

INTERVENTIONS

Patients received either blood product-based (period I) or FC-based (period II) hemostasis management to treat perioperative coagulopathy.

MEASUREMENTS AND MAIN RESULTS

Patients treated with FC management experienced less postoperative blood loss (907 v 1,153 mL, p = 0.014) and required less red blood cell and fresh frozen plasma transfusion (2.3 v 3.7 units p < 0.0001, and 2.0 v 3.4 units p < 0.0001, respectively) compared with subjects in the blood product-based management group. The frequency of Stage 3 acute kidney injury and 30-day mortality rate were significantly higher in the blood product-based group than in the FC management group (6.8% v 0.8%, p = 0.016, and 7.2% v 0.8%, p = 0.022, respectively). FC management-related thromboembolic events were not registered. The FC strategy was associated with a 2.19-fold decrease in the odds of massive postoperative bleeding (p < 0.0001), a 2.56-fold decrease in the odds of polytransfusion (p < 0.0001), and a 13.16-fold decrease in the odds of early postoperative death (p = 0.003).

CONCLUSIONS

FC-based versus blood product-based management is associated with reduced blood product needs and fewer complications, and was not linked to a higher frequency of thromboembolic events or a decrease in long-term survival in cardiac surgical patients developing perioperative coagulopathy and bleeding.

Elements not Graded in the Cardiac Enhanced Recovery After Surgery Guidelines Might Improve Postoperative Outcome: A Comprehensive Narrative Review

Enhanced Recovery Programs (ERPs) are protocols involving the whole patient surgical journey. These protocols are based on multimodal, multidisciplinary, evidence-based, and patient-centered approaches aimed at improving patient recovery after a surgical intervention. Such programs have shown striking positive results in different surgical specialties. However, only a few research groups have incorporated preoperative, intraoperative, and postoperative evidence-based interventions in bundles used to standardize care and build cardiac surgery ERPs. The Enhanced Recovery After Surgery Society recently published evidence-based recommendations for perioperative care in cardiac surgery. Their recommendations included 22 perioperative interventions that may be part of any cardiac ERP. However, various components integrated in already-published cardiac ERPs were neither graded nor reported in these recommendations. The goals of the current review are to present published cardiac ERPs and their effects on patient outcomes and reported components incorporated into these ERPs and to discuss the objectives and scope of cardiac ERPs.