Intraoperative cryoprecipitate transfusion and its association with the incidence of biliary complications after liver transplantation--a retrospective cohort study

Major Thromboembolic Complications in Liver Transplantation: The Role of Rotational Thromboelastometry and Cryoprecipitate Transfusion

BACKGROUND

Although hemorrhage is a major concern during liver transplantation (LT), the risk for thromboembolism is well recognized. Implementation of rotational thromboelastometry (ROTEM) has been associated with the increased use of cryoprecipitate; however, the role of ROTEM-guided transfusion strategy and cryoprecipitate administration in the development of major thromboembolic complications (MTCs) has never been documented.

METHODS

We conducted a study on patients undergoing LT before and after the implementation of ROTEM. We defined MTC as intracardiac thrombus, pulmonary embolism, hepatic artery thrombosis, and ischemic stroke in 30 d after LT. We used a propensity score to match patients during the 2 study periods.

RESULTS

Among 2330 patients, 119 (4.9%) developed MTC. The implementation of ROTEM was significantly associated with an increase in cryoprecipitate use (1.1 ± 1.1 versus 2.9 ± 2.3 units, P < 0.001) and MTC (4.2% versus 9.5%, P < 0.001). Further analysis demonstrated that the use of cryoprecipitate was an independent risk factor for MTC (odds ratio 1.1, 95% confidence interval 1.04-1.24, P = 0.003). Patients with MTC had significantly lower 1-y survival.

CONCLUSIONS

Our study suggests that the implementation of ROTEM and the use of cryoprecipitate play significant roles in the development of MTC in LT. The benefits and risks of cryoprecipitate transfusion should be carefully evaluated before administration.

The role of cryoprecipitate in human and canine transfusion medicine

OBJECTIVE

To evaluate the current role of cryoprecipitate in human and canine transfusion medicine.

DATA SOURCES

Human and veterinary scientific reviews and original studies found using PubMed and CAB Abstract search engines were reviewed.

HUMAN DATA SYNTHESIS

In the human critical care setting, cryoprecipitate is predominantly used for fibrinogen replenishment in bleeding patients with acute traumatic coagulopathy. Other coagulopathic patient cohorts for whom cryoprecipitate is recommended include those undergoing cardiovascular or obstetric procedures or patients bleeding from advanced liver disease. Preferential selection of cryoprecipitate versus fibrinogen concentrate (when available) is currently being investigated. Also a matter of ongoing debate is whether to administer this product as part of a fixed-dose massive hemorrhage protocol or to incorporate it into a goal-directed transfusion algorithm applied to the individual bleeding patient.

VETERINARY DATA SYNTHESIS

Although there are sporadic reports of the use of cryoprecipitate in dogs with heritable coagulopathies, there are few to no data pertaining to its use in acquired hypofibrinogenemic states. Low fibrinogen in dogs (as in people) has been documented with acute traumatic coagulopathy, advanced liver disease, and disseminated intravascular coagulation. Bleeding secondary to these hypocoagulable states may be amenable to cryoprecipitate therapy. Indications for preferential selection of cryoprecipitate (versus fresh frozen plasma) remain to be determined.

CONCLUSIONS

In the United States, cryoprecipitate remains the standard of care for fibrinogen replenishment in the bleeding human trauma patient. Its preferential selection for this purpose is the subject of several ongoing human clinical trials. Timely incorporation of cryoprecipitate into the transfusion protocol of the individual bleeding patient with hypofibrinogenemia may conserve blood products, mitigate adverse transfusion-related events, and improve patient outcomes. Cryoprecipitate is readily available, effective, and safe for use in dogs. The role of this blood product in clinical canine patients with acquired coagulopathy remains unknown.

Early versus late venous thromboembolism: A secondary analysis of data from the PROPPR trial

BACKGROUND

Factors predicting timing of post-traumatic venous thromboembolism (VTE) remain incompletely understood. Because the balance between hemorrhage and thrombosis is dynamic during a patient's hospital course, early and late VTE may be physiologically discrete processes. This secondary analysis of the Pragmatic, Randomized Optimal Platelet and Plasma Ratios (PROPPR) trial aims to explore whether certain risk factors are associated with early versus late VTE.

METHODS

The PROPPR trial investigated post-traumatic resuscitation with platelets, plasma, and red blood cells in a 1:1:1 ratio compared with a 1:1:2 ratio. Multinomial regression based on a threshold determined by cubic spline analysis tested the association of clinical variables with early or late VTE, a composite of deep vein thrombosis and pulmonary embolus, adjusting for predetermined confounders.

RESULTS

Of the 87 patients (13%) with VTE, pulmonary embolus was predominant in the first 72 hours. A statistically determined threshold at 12 days corresponded to change in odds of early versus late events. Variables associated with early VTE included plasma transfusion (risk ratio [RR] 1.14; 95% confidence interval, 1.00, 1.30; P = .05), sepsis (RR 0.05; 95% confidence interval, 1.40, 6.64; P = .01), pelvic or femur fracture (RR 2.62; 95% confidence interval, 1.00, 6.90; P = .05). Late VTE was associated with dialysis (RR 7.37; 95% confidence interval, 1.59, 34.14; P = .01), older age (RR 1.02; 95% confidence interval 1.00, 1.04; P = .05), and delayed resuscitation approaching ratios of 1:1:1 among patients randomized to 1:1:2 therapy (RR 2.06; 95% confidence interval, 0.28, 3.83; P = .02). Cyroprecipitate increased risk of early (RR 1.04, 95% confidence interval, 1.00,1.08; P < .03) and late VTE (1.05; 95% confidence interval, 1.01, 1.09; P = .01). Prolonged lagtime (coeffcient 0.06, 95% confidence interval, 0.02, 0.10; P < .01) and time-to-peak thrombin generation (coeffcient 0.04, 95% confidence interval, 0.02, 0.07; P < .01) were associated with increased risk of early VTE.

CONCLUSION

Early and late VTE may differ in their risk factors. Defining temporal trends in VTE may allow for a more individualized approach to thromboprophylaxis.

Association between viscoelastic tests-guided therapy with synthetic factor concentrates and allogenic blood transfusion in liver transplantation: a before-after study

Background

Perioperative bleeding and transfusion are important causes of morbidity and mortality in patients undergoing liver transplantation. The aim of this study is to assess whether viscoelastic tests-guided therapy with the use of synthetic factor concentrates impact transfusion rates of hemocomponents in adult patients undergoing liver transplantation.

Methods

This is an interventional before-after comparative study. Patients undergoing liver transplantation before the implementation of a protocol using thromboelastometry and synthetic factor concentrates were compared to patients after the implementation. Primary outcome was transfusion of any hemocomponents. Secondary outcomes included: transfusion of red blood cells (RBC), fresh frozen plasma (FFP), cryoprecipitate or platelets, clinical complications, length of stay and in-hospital mortality.

Results

A total of 183 patients were included in the control and 54 in the intervention phase. After propensity score matching, the proportion of patients receiving any transfusion of hemocomponents was lower in the intervention phase (37.0 vs 58.4%; OR, 0.42; 95% CI, 0.20–0.87; p = 0.019). Patients in the intervention phase received less RBC (30.2 vs 52.5%; OR, 0.21; 95% CI, 0.08–0.56; p = 0.002) and FFP (5.7 vs 27.3%; OR, 0.11; 95% CI, 0.03–0.43; p = 0.002). There was no difference regarding transfusion of cryoprecipitate and platelets, complications related to the procedure, hospital length of stay and mortality.

Conclusions

Use of a viscoelastic test-guided transfusion algorithm with the use of synthetic factor concentrates reduces the transfusion rates of allogenic blood in patients submitted to liver transplantation.

Trial registration

This trial was registered retrospectively on November 15th, 2018 – clinicaltrials.gov – Identifier: NCT03756948.

Electronic supplementary material

The online version of this article (10.1186/s12871-018-0664-8) contains supplementary material, which is available to authorized users.

Blood Products

Perioperative hemorrhage, anemia, thrombocytopenia, and coagulopathy are common in the surgical intensive care unit. As a result, blood product transfusion occurs frequently. While red blood cell, plasma, and platelet transfusions have a lifesaving role in the resuscitation of patients with trauma and hemorrhagic shock, their application in other settings is under scrutiny. Current data would suggest a conservative approach be taken, thus avoiding unnecessary transfusion and associated potential adverse events. New and developmental products such as prothrombin complex concentrates offer appealing alternatives to traditional transfusion practice—potentially with fewer risks—however, further investigation into their safety and efficacy is required before practice change can take place.

[The cryoprecipitate: that old unknown]

Cryoprecipitate is a plasma derivative rich in fibrinogen and other procoagulant factors. It has been successfully used for decades in the treatment of the coagulopathy of trauma patients, cardiovascular surgery, liver failure and disseminated intravascular coagulation. Although cryoprecipitate is routinely used in many western countries, most of the Spanish regional blood banks stopped its production in the late 1990's. Moreover, in recent years there is a movement to replace cryoprecipitate with manufactured fibrinogen concentrate. As a consequence, many of the younger anaesthesiologists did not have any direct experience with cryoprecipitate. This article aims to describe the characteristics of cryoprecipitate since it is a different product from manufactured fibrinogen concentrate, with its own specific indications that deserve to be further studied in clinical trials.

Cryoprecipitate therapy

Cryoprecipitate, originally developed as a therapy for patients with antihaemophilic factor deficiency, or haemophilia A, has been in use for almost 50 yr. However, cryoprecipitate is no longer administered according to its original purpose, and is now most commonly used to replenish fibrinogen levels in patients with acquired coagulopathy, such as in clinical settings with haemorrhage including cardiac surgery, trauma, liver transplantation (LT), or obstetric haemorrhage. Cryoprecipitate is a pooled product that does not undergo pathogen inactivation, and its administration has been associated with a number of adverse events, particularly transmission of blood-borne pathogens and transfusion-related acute lung injury. As a result of these safety concerns, along with emerging availability of alternative fibrinogen preparations, cryoprecipitate has been withdrawn from use in a number of European countries. Compared with the plasma from which it is prepared, cryoprecipitate contains a high concentration of coagulation factor VIII, coagulation factor XIII, and fibrinogen. Cryoprecipitate is usually licensed by regulatory authorities for the treatment of hypofibrinogenaemia, and recommended for supplementation when plasma fibrinogen levels decrease below 1 g litre(-1); however, this threshold is empiric and is not based on solid clinical evidence. Consequently, there is uncertainty over the appropriate dosing and optimal administration of cryoprecipitate, with some guidelines from professional societies to guide clinical practice. Randomized, controlled trials are needed to determine the clinical efficacy of cryoprecipitate, compared with the efficacy of alternative preparations. These trials will allow the development of evidence-based guidelines in order to inform physicians and guide clinical practice.

Bile duct strictures after liver transplantation

PURPOSE OF REVIEW

Biliary complications account for relevant morbidity and mortality after liver transplantation. Advances have taken place in understanding their aetiology, in preventive operative techniques, imaging procedures, as well as interventional and endoscopic management. However, progress in living donation, donation after cardiac death as well as paediatric transplant procedures have changed the incidence and causes of biliary complications. This review summarizes recent progress in the field, particularly related to biliary strictures after liver transplantation.

RECENT FINDINGS

Significant findings in the period of interest for this review focussed on improvements of endoscopic treatment of postliver transplant biliary complications, including novel stenting devices, the routine analysis of bacterial and fungal flora, and the use of steroids to prevent postendoscopic retrograde cholangiopancreaticography pancreatitis. The importance of cytomegalovirus and hepatitis C in the aetiology of biliary complications was highlighted. Under certain circumstances, biliary complications after liver transplantation of organs secondary to donation after cardiac death may be reduced to a level known from liver transplantation after brain death. Further evidence was added to support the risk-adapted use of biliary drainage during liver transplantation.

SUMMARY

The ongoing research in the aetiology, prevention, and treatment of biliary strictures after liver transplantation highlights the significance of biliary complications for patient and graft outcome.