Abstract

IMPORTANCE Excessive bleeding requiring fibrinogen replacement is a serious complication of cardiac surgery. However, the relative cost-effectiveness of the 2 available therapies-fibrinogen concentrate and cryoprecipitate-is unknown. OBJECTIVE To determine cost-effectiveness of fibrinogen concentrate vs cryoprecipitate for managing active bleeding in adult patients who underwent cardiac surgery. DESIGN, SETTING, AND PARTICIPANTS A within-trial economic evaluation of the Fibrinogen Replenishment in Surgery (FIBERS) randomized clinical trial (February 2017 to November 2018) that took place at 4 hospitals based in Ontario, Canada, hospitals examined all in-hospital resource utilization costs and allogeneic blood product (ABP) transfusion costs incurred within 28 days of surgery. Participants included a subset of 495 adult patients from the FIBERS trial who underwent cardiac surgery and developed active bleeding and acquired hypofibrinogenemia requiring fibrinogen replacement. INTERVENTIONS Fibrinogen concentrate (4 g per dose) or cryoprecipitate (10 units per dose) randomized (1:1) up to 24 hours postcardiopulmonary bypass. MAIN OUTCOMES AND MEASURES Effectiveness outcomes included number of ABPs administered within 24 hours and 7 days of cardiopulmonary bypass. ABP transfusion (7-day) and in-hospital resource utilization (28-day) costs were evaluated and a multivariable net benefit regression model built for the full sample and predefined subgroups. RESULTS Patient level costs for 495 patients were evaluated (mean [SD] age 59.2 [15.4] years and 69.3% male.) Consistent with FIBERS, ABP transfusions and adverse events were similar in both treatment groups. Median (IQR) total 7-day ABP cost was CAD $2280 (US dollars [USD] $1697) (CAD $930 [USD $692]-CAD $4970 [USD $3701]) in the fibrinogen concentrate group and CAD $2770 (USD $1690) (IQR, CAD $1140 [USD $849]-CAD $5000 [USD $3723]) in the cryoprecipitate group. Median (interquartile range) total 28-day cost was CAD $38 180 (USD $28 431) $(IQR, CAD $26 350 [USD $19 622]-CAD $65 080 [USD $48 463]) in the fibrinogen concentrate group and CAD $38 790 (USD $28 886) (IQR, CAD $26 180 [USD $19 495]-CAD $70 380 [USD $52 409]) in the cryoprecipitate group. After exclusion of patients who were critically ill before surgery (11%) due to substantial variability in costs, the incremental net benefit of fibrinogen concentrate vs cryoprecipitate was positive (probability of being cost-effective 86% and 97% at $0 and CAD $2000 (USD $1489) willingness-to-pay, respectively). Net benefit was highly uncertain for nonelective and patients with critical illness. CONCLUSIONS AND RELEVANCE Fibrinogen concentrate is cost-effective when compared with cryoprecipitate in most bleeding adult patients who underwent cardiac surgery with acquired hypofibrinogenemia requiring fibrinogen replacement. The generalizability of these findings outside the Canadian health system needs to be verified.

Abstract

BACKGROUND Liver transplantation (LT) is frequently complicated by coagulopathy associated with end-stage liver disease which is often multifactorial. OBJECTIVES The objective of this systematic review was to identify evidence-based intraoperative transfusion and coagulation management strategies that improve immediate and short-term outcomes after LT. METHODS PRISMA-guidelines and GRADE-approach were followed. Three sub-questions were formulated. (Q); Q1: transfusion management; Q2: antifibrinolytic therapy; and Q3: coagulation monitoring. RESULTS 16 studies were included for Q1, 6 for Q2, and 10 for Q3. Q1: PRBC and platelet transfusions were associated with higher mortality. The use of prothrombin complex concentrate (PCC) and fibrinogen concentrate (FC) were not associated with reductions in intraoperative transfusion or increased thrombotic events. The use of cell salvage was not associated with HCC recurrence or mortality. Cell salvage and transfusion education significantly decreased blood product transfusions. Q2: Epsilon-aminocaproic acid and Tranexamic acid were not associated with decreased blood product transfusion, improvements in patient or graft survival, or increases in thrombotic events. Q3: Viscoelastic testing was associated with decreased allogeneic blood product transfusion compared to conventional coagulation tests and are likely to be cost-effective. Coagulation management guided by VET may be associated with increases in fibrinogen concentrate and PCC use. CONCLUSION Q1: A specific blood product transfusion practice is not recommended. (QOE; low Recommendation; weak). Cell salvage and educational interventions are recommended. (QOE: low | Grade of Recommendation: moderate). Q2: The routine use of antifibrinolytics is not recommended. (QOE; low | Recommendation; weak). Q3: The use of VET is recommended. (QOE; low-moderate | Recommendation; strong). This article is protected by copyright. All rights reserved.

Abstract

BACKGROUND AND OBJECTIVES This sub-study of the FIBRES trial sought to examine the patterns of ABO-compatible cryoprecipitate administration and to identify adverse consequences of ABO-incompatible cryoprecipitate. MATERIALS AND METHODS This was a post hoc analysis of data collected from the FIBRES randomized clinical trial comparing fibrinogen concentrate with cryoprecipitate in the treatment of bleeding related to hypofibrinogenemia after cardiac surgery. The primary outcome was the percentage of administered cryoprecipitate that was ABO-compatible. Secondary outcomes were adverse events at 28 days. A follow-up survey was distributed to the FIBRES participating sites to examine the rationale behind the identified cryoprecipitate ABO-matching practice patterns. RESULTS A total of 363 patients were included: 53 (15%) received ABO-incompatible cryoprecipitate and 310 (85%) received ABO-compatible cryoprecipitate. There was an increased incidence of post-operative anaemia in the ABO-incompatible group (15; 28.3%) in comparison to the ABO-compatible (44; 14.2%) group (p = 0.01) at 28 days, which was unrelated to haemolysis, without a significant difference in transfusion requirement. In the multivariable logistic regression models accounting for clustering by site, there was no observed statistically significant association between the administration of ABO-incompatible cryoprecipitate and any other adverse outcomes. Nine out of 11 sites did not have a policy requiring ABO-matched cryoprecipitate. CONCLUSION This sub-study demonstrated that most cryoprecipitate administered in practice is ABO-compatible, despite the absence of guidelines or blood bank policies to support this practice. A signal towards increased risk of post-operative anaemia may be explained by higher rates of urgent surgery (vs. elective) in the ABO-incompatible group. Future studies should prospectively examine the impact of ABO-compatible versus incompatible cryoprecipitate to conclusively establish if there is a meaningful clinical impact associated with the administration of ABO-incompatible cryoprecipitate.

Abstract

BACKGROUND Coagulopathy in cardiac surgery is frequently associated with acquired hypofibrinogenaemia, which can be treated with either purified fibrinogen concentrate (FC) or cryoprecipitate. Because the latter is not purified and therefore contains additional coagulation factors, it is thought to be more effective for treatment of coagulopathy that occurs after prolonged cardiopulmonary bypass (CPB). We examined the impact of CPB duration on the efficacy of the two therapies in cardiac surgery. METHODS This was a post hoc analysis of the Fibrinogen Replenishment in Surgery (FIBRES) RCT comparing FC (4 g) to cryoprecipitate (10 U) in adult patients undergoing cardiac surgery and experiencing bleeding with acquired hypofibrinogenaemia (n=735). The primary outcome was allogeneic blood products transfused within 24 h after CPB. Subjects were stratified by CPB duration (≤120, 121-180, and >180 min). The interaction of treatment assignment with CPB duration was tested. RESULTS Subjects with longer CPB duration experienced more bleeding and transfusion. With CPB time ≤120 min (FC, n=134; cryoprecipitate, n=146), the ratio of least-squares means between the FC and cryoprecipitate groups for total allogeneic blood products at 24 h was 0.90 (one-sided 97.5% confidence interval [CI]: 0.00-1.12); P=0.004. For subjects with CPB time 121-180 min, it was 1.00 ([one-sided 97.5% CI: 0.00-1.22]; P=0.03], and for CPB time >180 min it was 0.91 ([one-sided 97.5% CI: 0.00-1.12]; P=0.005). Results were similar for all secondary outcomes, with no interaction between treatment and CPB duration for all outcomes. CONCLUSIONS The haemostatic efficacy of FC was non-inferior to cryoprecipitate irrespective of CPB duration in cardiac surgery. CLINICAL TRIAL REGISTRATION NCT03037424.

Abstract

PURPOSE Intravascular fluids are a necessary and universal component of cardiac surgical patient care. Both crystalloids and colloids are used to maintain or restore circulating plasma volume and ensure adequate organ perfusion. In Canada, human albumin solution (5% or 25% concentration) is a colloid commonly used for this purpose. In this narrative review, we discuss albumin supply in Canada, explore the perceived advantages of albumin, and describe the clinical literature supporting and refuting albumin use over other fluids in the adult cardiac surgical population. SOURCE We conducted a targeted search of PubMed, Embase, Medline, Web of Science, ProQuest Dissertations and Theses Global, the Cochrane Central Register of Controlled trials, and the Cochrane Database of Systematic Reviews. Search terms included albumin, colloid, cardiac surgery, bleeding, hemorrhage, transfusion, and cardiopulmonary bypass. PRINCIPAL FINDINGS Albumin is produced from fractionated human plasma and imported into Canada from international suppliers at a cost of approximately $21 million CAD per annum. While it is widely used in cardiac surgical patients across the country, it is approximately 30-times more expensive than equivalent doses of balanced crystalloid solutions, with wide inter-institutional variability in use and no clear association with improved outcomes. There is a general lack of high-quality evidence for the superiority of albumin over crystalloids in this patient population, and conflicting evidence regarding safety. CONCLUSIONS In cardiac surgical patients, albumin is widely utilized despite a lack of high- quality evidence supporting its efficacy or safety. A well-designed randomized controlled trial is needed to clarify the role of albumin in cardiac surgical patients.

Abstract

PURPOSE Albumin solution is a colloid used for resuscitation in cardiac surgical patients, but it is unclear if it offers advantages over crystalloids. We examined current clinical practice across 11 cardiac surgical centres and the association of albumin with outcomes in a cohort of bleeding cardiac surgical patients. METHODS This was a post hoc analysis of data from the Effect of Fibrinogen Concentrate vs Cryoprecipitate on Blood Component Transfusion After Cardiac Surgery (FIBRES) trial. Multivariable regression models adjusted for demographic and surgical characteristics were used to examine predictors of early albumin administration (within the initial 24 perioperative hours), late albumin administration (from 24 hr to seven days after cardiopulmonary bypass), and the association of albumin use with 28-day acute kidney injury, mortality, and length of hospital and intensive care unit (ICU) stay. RESULTS Of the 735 patients included, 525 (71%) received albumin, ranging from 4.8% to 97.4% of patients across institutions, with 475 (64.6%) receiving albumin early (5% or 25% solution). In the adjusted models, female sex and preoperative hospital admission were associated with early use, while heart failure, female sex, bleeding severity, older age, and prior albumin use were predictors of later administration. Early albumin use was not associated with differences in acute kidney injury (adjusted odds ratio [aOR] 1.77; 95% confidence interval [CI], 0.96 to 3.27; P = 0.07), mortality (aOR 1.66; 95% CI, 0.99 to 2.78; P = 0.05), or length of ICU stay (P = 0.11) or hospital stay (P = 0.67). CONCLUSIONS Albumin use is common but highly variable within and across sites. Albumin use was not associated with improved outcomes. High quality randomized controlled trials should clarify its role in cardiac surgical patients.

Abstract

PURPOSE The mainstay of therapy for coagulation factor deficiency in cardiac surgical patients is frozen plasma (FP); however, prothrombin complex concentrates (PCCs) may offer logistical and safety advantages. As there is limited comparative evidence, we conducted this study to explore the association of comparable PCC or FP doses with transfusion and outcomes. METHODS This was a post hoc analysis of a multicentre randomized trial comparing fibrinogen concentrate with cryoprecipitate (FIBRES trial) in bleeding cardiac surgical patients. This analysis included 415 patients who received only PCC (n = 72; 17%) or only FP (n = 343; 83%) for factor replacement. The main outcomes of interest were red blood cell (RBC) and platelet transfusion within 24 hr of cardiopulmonary bypass. Secondary outcomes included postoperative adverse events. Associations were examined by hierarchical generalized estimating equation models adjusted for demographic and surgical characteristics. RESULTS The median [interquartile range (IQR)] PCC dose was 1,000 [1,000-2,000] units, while the median [IQR] FP dose was 4 [2-6] units. Each unit of FP was independently associated with increased adjusted odds of RBC (1.60; 95% confidence interval [CI], 1.36 to 1.87; P < 0.01) and platelet transfusion (1.40; 95% CI, 1.15 to 1.69; P < 0.01) while each 500 units of PCC was independently associated with reduced adjusted odds of RBC (0.67; 95% CI, 0.50 to 0.90; P < 0.01) and platelet transfusion (0.80; 95% CI, 0.70 to 0.92; P < 0.01). Adverse event rates were comparable. CONCLUSIONS In cardiac surgical patients with post-cardiopulmonary bypass bleeding, PCC use was associated with lower RBC and platelet transfusion than FP use was. Prospective, randomized clinical trials comparing FP with PCC in this setting are warranted.

Abstract

IMPORTANCE Approximately 15% of patients undergoing cardiac surgery receive frozen plasma (FP) for bleeding. Four-factor prothrombin complex concentrates (PCCs) have logistical and safety advantages over FP and may be a suitable alternative. OBJECTIVES To determine the proportion of patients who received PCC and then required FP, explore hemostatic effects and safety, and assess the feasibility of study procedures. DESIGN, SETTING, AND PARTICIPANTS Parallel-group randomized pilot study conducted at 2 Canadian hospitals. Adult patients requiring coagulation factor replacement for bleeding during cardiac surgery (from September 23, 2019, to June 19, 2020; final 28-day follow-up visit, July 17, 2020). Data analysis was initiated on September 15, 2020. INTERVENTIONS Prothrombin complex concentrate (1500 IU for patients weighing ≤60 kg and 2000 IU for patients weighing >60 kg) or FP (3 U for patients weighing ≤60 kg and 4 U for patients weighing >60 kg), repeated once as needed within 24 hours (FP used for any subsequent doses in both groups). Patients and outcome assessors were blinded to treatment allocation. MAIN OUTCOMES AND MEASURES Hemostatic effectiveness (whether patients received any hemostatic therapies from 60 minutes to 4 and 24 hours after initiation of the intervention, amount of allogeneic blood components administered within 24 hours after start of surgery, and avoidance of red cell transfusions within 24 hours after start of surgery), protocol adherence, and adverse events. The analysis set comprised all randomized patients who had undergone cardiac surgery, received at least 1 dose of either treatment, and provided informed consent after surgery. RESULTS Of 169 screened patients, 131 were randomized, and 101 were treated (54 with PCC and 47 with FP), provided consent, and were included in the analysis (median age, 64 years; interquartile range [IQR], 54-73 years; 28 [28%] were female; 82 [81%] underwent complex operations). The PCC group received a median 24.9 IU/kg (IQR, 21.8-27.0 IU/kg) of PCC (2 patients [3.7%; 95% CI, 0.4%-12.7%] required FP). The FP group received a median 12.5 mL/kg (IQR, 10.0-15.0 mL/kg) of FP (4 patients [8.5%; 95% CI, 2.4%-20.4%] required >2 doses of FP). Hemostatic therapy was not required at the 4-hour time point for 43 patients (80%) in the PCC group and for 32 patients (68%) in the FP group (P = .25) nor at the 24-hour time point for 41 patients (76%) in the PCC group and for 31 patients (66%) patients in the FP group (P = .28). The median numbers of units for 24-hour cumulative allogeneic transfusions (red blood cells, platelets, and FP) were 6.0 U (IQR, 4.0-11.0 U) in the PCC group and 14.0 U (IQR, 8.0-20.0 U) in the FP group (ratio, 0.58; 95% CI, 0.45-0.77; P < .001). After exclusion of FP administered as part of the investigational medicinal product, the median numbers of units were 6.0 U (IQR, 4.0-11.0 U) in the PCC group and 10.0 U (IQR, 6.0-16.0 U) in the FP group (ratio, 0.80; 95% CI, 0.59-1.08; P = .15). For red blood cells alone, the median numbers were 1.5 U (IQR, 0.0-4.0 U) in the PCC group and 3.0 U (IQR, 1.0-5.0 U) in the FP group (ratio, 0.69; 95% CI, 0.47-0.99; P = .05). During the first 24 hours after start of surgery, 15 patients in the PCC group (28%) and 8 patients in the FP group (17%) received no red blood cells (P = .24). Adverse event profiles were similar. CONCLUSIONS AND RELEVANCE This randomized clinical trial found that the study protocols were feasible. Adequately powered randomized clinical trials are warranted to determine whether PCC is a suitable substitute for FP for mitigation of bleeding in cardiac surgery. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT04114643.