Reduction in blood transfusion in a cohort of infants having cardiac surgery with cardiopulmonary bypass after instituting a goal-directed transfusion policy

'Goal-directed extracorporeal circulation: transferring the knowledge and experience from daily cardiac surgery to extracorporeal membrane oxygenation'

Metabolism management plays an essential role in extracorporeal technologies. There are different metabolic management devices integrated to extracorporeal devices; the most commonly used and accepted metabolic target in adult patients is indexed oxygen delivery (280 mL/min/m²) and cardiac index (2.4 L/min/m²), which can be managed independently or according to other metabolic parameters. Extracorporeal membrane oxygenation (ECMO) is a temporary form of life support providing a prolonged biventricular circulatory and pulmonary support for patients experiencing both pulmonary and cardiac failure unresponsive to conventional therapy. The goal-directed perfusion initiative during cardiopulmonary bypass (CPB) reduced the incidence of acute kidney injury after cardiac surgery. On the basis of the available literature, the identified goals to achieve during CPB include maintenance of oxygen delivery > 300 mL O₂/min/m² and reduction in vasopressor use. ECMO and CPB are conceptually similar but differ in many aspects and finality; in particular, they differ in the scientific evidence for metabolic management nadirs. As for CPB, predictive target parameters have been found and consolidated, particularly in terms of acute renal injury and the prevention of anaerobic metabolism, while for ECMO management, a blurred path remains. In this context, we review the strategies for optimal goal-directed therapy during CPB and ECMO, trying to transfer the knowledge and experience from daily cardiac surgery to veno-arterial ECMO.

Prevention of postoperative bleeding after complex pediatric cardiac surgery by early administration of fibrinogen, prothrombin complex and platelets: a prospective observational study

Background

Postoperative bleeding is a major problem in children undergoing complex pediatric cardiac surgery. The primary aim of this prospective observational study was to evaluate the effect of an institutional approach consisting of early preventive fibrinogen, prothrombin complex and platelets administration on coagulation parameters and postoperative bleeding in children. The secondary aim was to study the rate of re-intervention and postoperative transfusion, the occurrence of thrombosis, length of mechanical ventilation, ICU stay and mortality.

Methods

In fifty children (age 0–6 years) with one or more predefined risk factors for bleeding after cardiopulmonary bypass (CPB), thrombelastography (TEG) and standard coagulation parameters were measured at baseline (T1), after CPB and reversal of heparin (T2), at sternal closure (T3) and after 12 h in the ICU (T4). Clinical bleeding was evaluated by the surgeon at T2 and T3 using a numeric rating scale (NRS, 0–10).

Results

After CPB and early administration of fibrinogen, prothrombin complex and platelets, the clinical bleeding evaluation score decreased from a mean value of 6.2 ± 1.9 (NRS) at T2 to a mean value of 2.1 ± 0.8 at T3 (NRS; P <  0.001). Reaction time (R), kinetic time (K), maximum amplitude (MA) and maximum amplitude of fibrinogen (MA-fib) improved significantly (P <  0.001 for all), and MA-fib correlated significantly with the clinical bleeding evaluation (r = 0.70, P <  0.001). The administered total amount of fibrinogen (mg kg^− 1) correlated significantly with weight (r = − 0.42, P = 0.002), priming volume as percentage of estimated blood volume (r = 0.30, P = 0.034), minimum CPB temperature (r = − 0.30, P = 0.033) and the change in clinical bleeding evaluation from T2 to T3 (r = 0.71, P <  0.001). The incidence of postoperative bleeding (> 10% of estimated blood volume) was 8%. No child required a surgical re-intervention, and no cases of thrombosis were observed. Hospital mortality was 0%.

Conclusion

In this observational study of children with an increased risk of bleeding after CPB, an early preventive therapy with fibrinogen, prothrombin complex and platelets guided by clinical bleeding evaluation and TEG reduced bleeding and improved TEG and standard coagulation parameters significantly, with no occurrence of thrombosis or need for re-operation.

Trial registration

German Clinical Trials Register DRKS00018109 (retrospectively registered 27th August 2019).

Red blood cell transfusion threshold after pediatric cardiac surgery: A systematic review and meta-analysis

BACKGROUND

Restrictive red blood cell transfusion strategy is implemented to minimize risk following allogeneic blood transfusion in adult cardiac surgery. However, it is still unclear if it can be applied to pediatric cardiac patients. The purpose of this systematic review and meta-analysis was to determine the effect of postoperative restrictive transfusion thresholds on clinical outcomes based on up-to-date results of randomized controlled trials (RCTs) and observational studies in pediatric cardiac surgery.

METHOD

We searched for RCTs and observational studies in the following databases: the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and ClinicalTrials.gov from their inception to October 26, 2017. We also searched reference lists of published guidelines, reviews, and relevant articles, as well as conference proceedings. No language restrictions were applied and no observational study met the inclusion criteria.

RESULTS

Four RCTs on cardiac surgery involving 454 patients were included. There were no differences in the pooled fixed effects of intensive care unit (ICU) stay between the liberal and restrictive transfusion thresholds (standardized mean difference SMD, 0.007; 95% confidence interval CI, -0.18-0.19; P = .94). There were also no differences in the length of hospital stay (SMD, -0.062; 95% CI, -0.28-0.15; P = .57), ventilation duration (SMD, -0.015; 95% CI, -0.25-0.22; P = .90), mean arterial lactate level (SMD, 0.071; 95% CI, -0.22-0.36; P = .63), and mortality (risk ratio, 0.49; 95% CI, 0.13-1.94; P = .31). There was no inter-trial heterogeneity for any pooled analysis. Publication bias was tested using Egger, Begg, or the trim-and-fill test, and the results indicated no significant publication bias.

CONCLUSION

Evidence from RCTs in pediatric cardiac surgery, though limited, showed non-inferiority of restrictive thresholds over liberal thresholds in length of ICU stay and other outcomes following red blood cell transfusion. Further high-quality RCTs are necessary to confirm the findings.

A Review of Goal-Directed Cardiopulmonary Bypass Management in Pediatric Cardiac Surgery

Cardiopulmonary bypass perfusion management significantly affects postoperative outcomes. In recent years, the principles of goal-directed therapy have been applied to the field of cardiothoracic surgery to improve patient outcomes. Goal-directed therapy involves continuous peri- and postoperative monitoring of vital clinical parameters to tailor perfusion to each patient's specific needs. Closely measured parameters include fibrinogen, platelet count, lactate, venous oxygen saturation, central venous oxygen saturation, mean arterial pressure, perfusion flow rate, and perfusion pulsatility. These parameters have been shown to influence postoperative fresh frozen plasma transfusion rate, coagulation state, end-organ perfusion, and mortality. In this review, we discuss the recent paradigm shift in pediatric perfusion management toward goal-directed perfusion.

Strategies for Prevention and Management of Bleeding Following Pediatric Cardiac Surgery on Cardiopulmonary Bypass: A Scoping Review

OBJECTIVE

We aimed to systematically describe, via a scoping review, the literature reporting strategies for prevention and management of mediastinal bleeding post pediatric cardiopulmonary bypass surgery.

DATA SOURCES

MEDLINE, EMBASE, PubMed, and Cochrane CENTRAL Register.

STUDY SELECTION

Two authors independently screened publications from 1980 to 2016 reporting the effect of therapeutic interventions on bleeding-related postoperative outcomes, including mediastinal drain loss, transfusion, chest re-exploration rate, and coagulation variables. Inclusions: less than 18 years, cardiac surgery on cardiopulmonary bypass.

DATA EXTRACTION

Data from eligible studies were extracted using a standard data collection sheet.

DATA SYNTHESIS

Overall, 299 of 7,434 screened articles were included, with observational studies being almost twice as common (n = 187, 63%) than controlled trials (n = 112, 38%). The most frequently evaluated interventions were antifibrinolytic drugs (75 studies, 25%), blood products (59 studies, 20%), point-of-care testing (47 studies, 16%), and cardiopulmonary bypass circuit modifications (46 studies, 15%). The publication rate for controlled trials remained constant over time (4-6/yr); however, trials were small (median participants, 51; interquartile range, 57) and overwhelmingly single center (98%). Controlled trials originated from 22 countries, with the United States, India, and Germany accounting for 50%. The commonest outcomes were mediastinal blood loss and transfusion requirements; however, these were defined inconsistently (blood loss being reported over nine different time periods). The majority of trials were aimed at bleeding prevention (98%) rather than treatment (10%), nine studies assessed both.

CONCLUSIONS

Overall, this review demonstrates small trial sizes, low level of evidence, and marked heterogeneity of reported endpoints in the included studies. The need for more, higher quality studies reporting clinically relevant, comparable outcomes is highlighted. Emerging fields such as the use of coagulation factor concentrates, goal-directed guidelines, and anti-inflammatory therapies appear to be of particular interest. This scoping review can potentially guide future trial design and form the basis for therapy-specific systematic reviews.

Prothrombin Complex Concentrates in Pediatric Cardiac Surgery: The Current State and the Future

BACKGROUND

After decades of practice of pediatric cardiac surgery, postoperative bleeding due to the immaturity of hemostasis, hemodilution, and hypothermia remains a concern. Recently, a new approach for adult coagulopathy after bypass has emerged. Prothrombin complex concentrates (PCCs), designed to treat bleeding in hemophilia patients, are safely and efficiently used off label for hemorrhage after bypass. However, optimal dosing, indications and contraindications, and laboratory tests to assess the efficacy of PCC use in children have not yet been established. This literature review outlines the challenges of bypass-related coagulopathy, the pharmacology, and the experience in use of PCCs, with a focus on their potential in pediatric cardiac surgery.

METHODS

After a thorough literature search of MEDLINE, Scopus, and Ovid databases using the term "prothrombin complex concentrate AND pediatric," 23 relevant articles were selected.

RESULTS

The data supporting successful use of PCCs in acquired coagulopathy after cardiac surgery in adults have been increasing. Although small volume, low immunogenicity, efficiency, and speed in correcting coagulopathy are attractive qualities of PCCs for pediatric practice, current evidence is only anecdotal. The main concerns are unknown dosing regimens, the inability to closely monitor the effects of PCCs in real time, and a possibility of thrombotic complications, which can be particularly devastating in young congenital cardiac patients whose lives frequently depend upon the patency of artificial shunts.

CONCLUSIONS

Extensive, high-quality research is warranted to fill in the gaps of knowledge regarding using PCCs in pediatric cardiac practice.