Quality Management of a Comprehensive Blood Conservation Program During Cardiopulmonary Bypass

Effect of mild hypothermia vs normothermia cardiopulmonary bypass on postoperative bleeding in patients undergoing coronary artery bypass grafting: protocol of a multi-center, randomized, controlled trial

BACKGROUND

Coronary artery bypass grafting (CABG) is often performed with hypothermic cardiopulmonary bypass (CPB) to reduce metabolic demands and protect the myocardium. However, hypothermia can increase bleeding risks and other complications.

METHODS

This is a prospective, multi-center, randomized controlled trial. From September 2023 to December 2024, a total of 336 eligible patients planning to undergo on-pump CABG will be enrolled. All participants will be randomly divided into mild hypothermia CPB group (target oxygenator arterial outlet blood temperature at 32-33℃) or normothermia CPB group (target oxygenator arterial outlet blood temperature at 35-36℃). The primary endpoint is Universal Definition of Perioperative Bleeding (UDPB) class 2-4. Secondary endpoints are class of UDPB, levels of coagulation and inflammatory factors, in-hospital mortality, perioperative related complications, ICU length of stay, and hospital length of stay.

DISCUSSION

This clinical trial aims to compare the effects of different target temperature during CPB on postoperative bleeding and to explore optimal temperature strategy to provide new clinical evidence.

TRIAL REGISTRATION

Chictr.org.cn : ChiCTR2300075405. The trial was prospectively registered on 4 September 2023.

A modified low-priming cardiopulmonary bypass system in patients undergoing cardiac surgery with medium risk of transfusion: A randomized controlled trial

Objectives

The FUWAI-SAVE system is a modified low-priming cardiopulmonary bypass (CPB) system. The study aimed to explore whether the FUWAI-SAVE system can reduce the perioperative blood transfusion and its impact on other postoperative complications during cardiac surgery.

Metohds

This study was a single-center, single-blind, randomized controlled trial, registered at the Chinese Clinical Trial Registry (identifier: ChiCTR2100050488). Adult patients undergoing cardiac surgery with CPB and intermediate risk for transfusion risk stratification were randomly assigned to an intervention group (FUWAI-SAVE group) or a control group (conventional group). The primary endpoint of the study was the peri-CPB red blood cell transfusion (RBC) rate. The secondary endpoints included the transfusion rate of other blood products, the amount of blood products transfused, the incidence of major complications, in-hospital mortality, and others.

Results

360 patients were randomized from December 9, 2021, to January 30, 2023. The rate of the primary endpoint was significantly lower in the FUWAI-SAVE group compared to the control group [ OR (95%CI): 0.649 (0.424-0.994)]. Meanwhile, the amount of RBC transfusion during the peri-CPB period was significantly lower in the FUWAI-SAVE group compared to the control group, with a mean difference of -0.626 (-1.176 to -0.076) units. The occurrence rate of major complications did not differ significantly between the two groups.

Conclusions

Among adult patients undergoing cardiac surgery with CPB, the application of the FUWAI-SAVE system significantly reduced RBC transfusion rate and amount. The FUWAI-SAVE system can be considered an important component of comprehensive blood management strategies in cardiac surgery.

The impact of comprehensive blood conservation program on major complications after total aortic arch replacement

INTRODUCTION

Patients undergoing total aortic arch replacement (TAAR) usually require blood products perioperatively. This cohort study aimed to investigate the impact of a comprehensive blood conservation program on the major complications in these patients.

METHODS

Patients with traditional or comprehensive blood management intraoperatively from January 2017 to December 2018 were included. We compared the rates of major complications (cerebral vascular accident, acute kidney injury, or mortality) between the two groups after propensity score matching (PSM). The association between blood management and outcomes was assessed by logistic regression. Restricted cubic splines (RCS) were built to evaluate the impact of fresh frozen plasma (FFP) on complications. Patients were stratified by the ratio of FFP/RBC (red blood cell) to investigate the effect of the ratio on complications.

RESULTS

After 1:1 PSM, 200 patients were selected. 35% (35/100) of patients suffered major complications in the traditional group, while it decreased to 22% (22/100) in the comprehensive management group (OR = 0.524, p = 0.043). Multivariable logistic regression showed that FFP was a risk factor (OR = 1.186, p = 0.014). RCS results indicated that with the increase of FFP, the risk of complications gradually increases. The cut-off value was 402 mL. Patients in the group of ratio = 0 ∼ 0.5 had a higher chance than those without transfusion (OR = 7.487, p < 0.001).

CONCLUSIONS

Comprehensive blood conservation program in patients undergoing TAAR is safe and can reduce the incidence of major complications, which are associated with FFP volume and the ratio of FFP/RBC.

A Comprehensive Patient Blood Management Program During Cardiopulmonary Bypass in Patients Over 60 Years of Age

Purpose

There is currently no consensus on the most appropriate blood transfusion strategy for older adults undergoing cardiovascular surgery. We aimed to investigate the potential benefits of the patient blood management (PBM) program specifically for advanced age patients, and to evaluate the relationship of age and PBM in cardiovascular surgery.

Patients and Methods

We collected data from patients over 60 years old who underwent on-pump cardiovascular surgery. We compared transfusion and clinical outcomes between the pre-PBM and post-PBM groups using a propensity score matching method. Then, we conducted a subgroup analysis within the original cohort, specifically focusing on patients aged of 75 and above with multivariable adjusted models.

Results

Data of 9703 older adults were analyzed. Red blood cell (RBC) transfusion rates during cardiopulmonary bypass (CPB) (31.6% vs 13.1%, P<0.001), during the operation (50.8% vs 39.0%, P<0.001) and after the operation (5.6% vs 3.1%, P<0.001) were significantly reduced, and mortality and the risk of some adverse events were also reduced after the PBM. Subgroup analysis showed that there was no interaction between age and PBM, and advanced age (over age 75) did not modify the effect of PBM program in reducing RBC transfusion (Pinteraction=0.245), on mortality (Pinteration=0.829) and on certain complications.

Conclusion

The comprehensive PBM program could reduce RBC transfusion without adverse outcomes in older patients undergoing CPB. Even patients over age 75 may benefit from a more stringent transfusion indication. Comprehensive blood conservation measures should be applied to optimize the blood management for older patients.

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.

Dose-dependent influence of red blood cell transfusion volume on adverse outcomes in cardiac surgery

INTRODUCTION

Red blood cell (RBC) transfusion is associated with adverse outcomes, but there are few studies on the RBC volume. This study aimed to evaluate the relationship between intraoperative RBC volume and postoperative adverse outcomes for on-pump cardiac surgery.

METHODS

Adult patients undergoing on-pump cardiac surgery from 1 January 2017 to 31 December 2018 were included. Those transfused with more than 6 units of RBC were excluded. The clinical characteristics of four groups with various RBC volume were compared. We analyzed the relationship between RBC volume and adverse outcomes through multivariable logistic regression.

RESULTS

12,143 patients were analyzed, of which 3353 (27.6%) were transfused with 1-6U RBC intraoperatively. The incidence of death, overall morbidity, acute kidney injury and prolonged mechanical ventilation were increased stepwise along with incremental RBC volume. After adjusting for possible confounders, patients transfused with 1-2U were associated with a 1.42-fold risk of death (99% CI, 1.21-2.34, p = 0.01) compared with patients without RBC, patients with 3-4U were associated with a 1.57-fold risk (99% CI, 1.32-2.80, p = 0.005) and patients with 5-6U had a 2.26-fold risk of death (99% CI, 1.65-3.88, p < 0.001). Similarly, the incidence of overall morbidity, acute kidney injury and prolonged mechanical ventilation increased several folds as the RBC numbers increased.

CONCLUSIONS

There was a significant dose-dependent influence of incremental intraoperative RBC volume on increased risk of adverse outcomes for on-pump cardiac surgery patients. Patient blood management practice should aim to reduce not only transfusion rate but also the volume of blood use.

A transfusion risk stratification score to facilitate quality management in cardiopulmonary bypass

BACKGROUND

Our previous showed that a blood management program in the cardiopulmonary bypass (CPB) department, reduced red blood cell (RBC) transfusion and complications, but assessing transfusion practice solely based on transfusion rates was insufficient. This study aimed to design a risk stratification score to predict perioperative RBC transfusion to guide targeted measures for on-pump cardiac surgery patients.

STUDY DESIGN AND METHODS

We analyzed data from 42,435 adult cardiac patients. Eight predictors were entered into the final model including age, sex, anemia, New York Heart Association classification, body surface area, cardiac surgery history, emergency surgery, and surgery type. We then simplified the score to an integer-based system. The area under the receiver operating characteristic curve (AUC), Hosmer-Lemeshow goodness-of-fit test, and a calibration curve were used for its performance test. The score was compared to existing scores.

RESULTS

The final score included eight predictors. The AUC for the model was 0.77 (95% CI, 0.76-0.77) and 0.77 (95% CI, 0.76-0.78) in the training and test set, respectively. The calibration curves showed a good fit. The risk score was finally grouped into low-risk (score of 0-13 points), medium-risk (14-19 points), and high-risk (more than 19 points). The score had better predictive power compared to the other two existing risk scores.

DISCUSSION

We developed an effective risk stratification score with eight variables to predict perioperative RBC transfusion for on-pump cardiac surgery. It assists perfusionists in proactively preparing blood conservation measures for high-risk patients before surgery.