Pro-coagulant haemostatic factors for the prevention and treatment of bleeding in patients without haemophilia

Blood transfusion strategies for major bleeding in trauma

BACKGROUND

Trauma is a leading cause of morbidity and mortality worldwide. Research shows that haemorrhage and trauma-induced coagulopathy are reversible components of traumatic injury, if identified and treated early. Lack of consensus on definitions and transfusion strategies hinders the translation of this evidence into clinical practice.

OBJECTIVES

To assess the beneficial and harmful effects of transfusion strategies started within 24 hours of traumatic injury in adults (aged 16 years and over) with major bleeding.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, five other databases, and three trial registers were searched on 20 November 2023. We also checked reference lists of included studies to identify any additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of adults (aged 16 years and over) receiving blood products for the management of bleeding within 24 hours of traumatic injury.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology to perform the review and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 18 RCTs with 5041 participants. Comparison 1: Prehospital transfusion strategies Five studies compared use of plasma (fresh frozen plasma (FFP) or lyophilised plasma) versus 'standard of care'. We are uncertain of the effect of plasma on all-cause mortality at 24 hours (risk ratio (RR) 1.05, 95% confidence interval (CI), 0.48 to 2.30; 3 studies, 279 participants; very low certainty evidence). There is probably no difference between plasma and standard of care in all-cause mortality at 30 days (RR 0.95, 95% CI 0.78 to 1.17; 3 studies, 664 participants; moderate-certainty evidence). However, the results of one cluster-RCT that could not be included in our meta-analysis suggested that plasma may be associated with a lower risk of death at 30 days (RR 0.54, 95% CI 0.42 to 0.70; 1 study, 481 participants; low-certainty evidence). There may be no difference between plasma and standard of care in the total number of thromboembolic events in 30 days (RR 1.23, 95% CI 0.67 to.2.27; 4 studies, 586 participants; low-certainty evidence). Comparison 2: In-hospital transfusion strategies Ten studies evaluated this comparison, seven providing usable data. The studies evaluated cryoprecitate (three studies); fixed-ratio blood component transfusion (three studies); fresh frozen plasma (FFP) (one study); lyophilised plasma (one study); leucoreduced red blood cells (one study); and a restrictive transfusion strategy (one study). All-cause mortality at 24 hours For all-cause mortality at 24 hours, there is probably no difference between: • cryoprecipitate plus a major haemorrhage protocol (MHP) versus MHP alone (RR 0.92, 95% CI 0.70 to 1.21; 1 study, 1577 participants; moderate-certainty evidence); and • blood products (plasma:platelets:red blood cells (RBCs)) transfused in 1:1:1 ratio versus 1:1:2 ratio (RR 0.75, 95% CI 0.52 to 1.08; 1 study, 680 participants; moderate-certainty evidence). We are uncertain of the effect on all-cause mortality at 24 hours for: • blood products (RBCs:FFP) transfused in 1:1 ratio versus transfusion according to coagulation and full blood count results (Peto odds ratio (POR) 0.45, 0.17 to 1.22; 1 study, 434 participants; very low certainty evidence); and • lyophilised (FlyP) plasma versus FFP (POR 1.04, 95% CI 0.06 to 17.23; 1 study, 47 participants; very low certainty evidence); All-cause mortality at 30 days For all-cause mortality at 30 days, there is probably no difference between blood products (plasma:platelets:RBCs) transfused in a 1:1:1 ratio versus a 1:1:2 ratio (RR 0.85, 95% CI 0.65 to 1.11; 1 study, 680 participants; moderate-certainty evidence). There may be little to no difference between the following interventions in all-cause mortality at 30 days: • cryoprecipitate plus MHP versus MHP alone (RR 0.77, 95% CI 0.33 to 1.78; 2 studies, 1572 participants; low-certainty evidence); and •leucoreduced RBCs versus standard RBCs (RR 1.20, 95% CI 0.74 to 1.95; 1 study,55 participants; low certainty evidence). We are uncertain of the effect on all-cause mortality at 30 days for: •lyophilised plasma versus FFP (RR 0.75, 95% CI 0.28 to 2.02; 1 study, 47 participants; very low certainty evidence); and • blood products (plasma:platelets:RBCs) transfused in 1:1:1 ratio versus standard MHP (RR 2.25, 95% CI 0.90 to 5.62; 1 study, 69 participants; very low certainty evidence). Total number of thromboembolic events at 30 days There may be little to no difference between the following interventions for total thromboembolic events at 30 days: • cryoprecipitate plus MHP versus MHP alone (RR 0.55, 95% CI 0.08 to 3.72; 2 studies, 1645 participants; low-certainty evidence); and • blood products (plasma:platelets:RBCs) transfused in 1:1:1 ratio versus 1:1:2 ratio (RR 1.03, 95% CI 0.75 to 1.42; 1 study, 680 participants; low-certainty evidence). We are uncertain of the effect on the total number of thromboembolic events at 30 days for: •blood products (plasma:platelets:RBCs) transfused in 1:1:1 ratio versus standard MHP (POR 6.83, 95% CI 0.68 to 68.35; 1 study, 69 participants; very low certainty evidence). Comparison 3: Whole blood versus individual blood products We are uncertain of the effect of modified (leucoreduced) whole blood versus blood products (RBCs:plasma) transfused in a 1:1 ratio on all-cause mortality at 24 hours (RR 1.13, 95% CI 0.37 to 3.49) or 30 days (RR 1.62, 95% CI 0.69 to 3.80) (1 study, 107 participants; very low certainty evidence). Comparison 4: Goal-directed blood transfusion strategy of viscoelastic haemostatic assay (VHA) versus conventional laboratory coagulation tests (CCT) to guide haemostatic therapy There may be little or no difference in all-cause mortality at 24 hours between VHA and CCT (RR 0.85, 95% CI 0.54 to 1.35; 1 study, 396 participants; low-certainty evidence). We are uncertain of the effects on all-cause mortality at 30 days (RR 0.75, 95% CI 0.48 to 1.17; 2 studies, 506 participants; very low certainty evidence). There is probably no difference between VHA and CCT in total thromboembolic events at 30 days (RR 0.65, 95% CI 0.35 to 1.18; 1 study 396 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Overall, there was little to no evidence of a difference between blood transfusion strategies for mortality or thromboembolic events. The studies covered a wide range of interventions, and the comparators and standard of care practice varied between trials, thereby limiting the pooling of data. Further research is needed.

Prophylactic platelet transfusions prior to surgery for people with a low platelet count

BACKGROUND

People with thrombocytopenia often require a surgical procedure. A low platelet count is a relative contraindication to surgery due to the risk of bleeding. Platelet transfusions are used in clinical practice to prevent and treat bleeding in people with thrombocytopenia. Current practice in many countries is to correct thrombocytopenia with platelet transfusions prior to surgery. Alternatives to platelet transfusion are also used prior surgery.

OBJECTIVES

To determine the clinical effectiveness and safety of prophylactic platelet transfusions prior to surgery for people with a low platelet count.

SEARCH METHODS

We searched the following major data bases: Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), PubMed (e-publications only), Ovid MEDLINE, Ovid Embase, the Transfusion Evidence Library and ongoing trial databases to 11 December 2017.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs), as well as non-RCTs and controlled before-and-after studies (CBAs), that met Cochrane EPOC (Effective Practice and Organisation of Care) criteria, that involved the transfusion of platelets prior to surgery (any dose, at any time, single or multiple) in people with low platelet counts. We excluded studies on people with a low platelet count who were actively bleeding.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane for data collection. We were only able to combine data for two outcomes and we presented the rest of the findings in a narrative form.

MAIN RESULTS

We identified five RCTs, all conducted in adults; there were no eligible non-randomised studies. Three completed trials enrolled 180 adults and two ongoing trials aim to include 627 participants. The completed trials were conducted between 2005 and 2009. The two ongoing trials are scheduled to complete recruitment by October 2019. One trial compared prophylactic platelet transfusions to no transfusion in people with thrombocytopenia in an intensive care unit (ICU). Two small trials, 108 participants, compared prophylactic platelet transfusions to other alternative treatments in people with liver disease. One trial compared desmopressin to fresh frozen plasma or one unit of platelet transfusion or both prior to surgery. The second trial compared platelet transfusion prior to surgery with two types of thrombopoietin mimetics: romiplostim and eltrombopag. None of the included trials were free from methodological bias. No included trials compared different platelet count thresholds for administering a prophylactic platelet transfusion prior to surgery. None of the included trials reported on all the review outcomes and the overall quality per reported outcome was very low.None of the three completed trials reported: all-cause mortality at 90 days post surgery; mortality secondary to bleeding, thromboembolism or infection; number of red cell or platelet transfusions per participant; length of hospital stay; or quality of life.None of the trials included children or people who needed major surgery or emergency surgical procedures.Platelet transfusion versus no platelet transfusion (1 trial, 72 participants)We were very uncertain whether giving a platelet transfusion prior to surgery had any effect on all-cause mortality within 30 days (1 trial, 72 participants; risk ratio (RR) 0.78, 95% confidence interval (CI) 0.41 to 1.45; very-low quality evidence). We were very uncertain whether giving a platelet transfusion prior to surgery had any effect on the risk of major (1 trial, 64 participants; RR 1.60, 95% CI 0.29 to 8.92; very low-quality evidence), or minor bleeding (1 trial, 64 participants; RR 1.29, 95% CI 0.90 to 1.85; very-low quality evidence). No serious adverse events occurred in either study arm (1 trial, 72 participants, very low-quality evidence).Platelet transfusion versus alternative to platelet transfusion (2 trials, 108 participants)We were very uncertain whether giving a platelet transfusion prior to surgery compared to an alternative has any effect on the risk of major (2 trials, 108 participants; no events; very low-quality evidence), or minor bleeding (desmopressin: 1 trial, 36 participants; RR 0.89, 95% CI 0.06 to 13.23; very-low quality evidence: thrombopoietin mimetics: 1 trial, 65 participants; no events; very-low quality evidence). We were very uncertain whether there was a difference in transfusion-related adverse effects between the platelet transfused group and the alternative treatment group (desmopressin: 1 trial, 36 participants; RR 2.70, 95% CI 0.12 to 62.17; very-low quality evidence).

AUTHORS' CONCLUSIONS

Findings of this review were based on three small trials involving minor surgery in adults with thrombocytopenia. We found insufficient evidence to recommend the administration of preprocedure prophylactic platelet transfusions in this situation with a lack of evidence that transfusion resulted in a reduction in postoperative bleeding or all-cause mortality. The small number of trials meeting the inclusion criteria and the limitation in reported outcomes across the trials precluded meta-analysis for most outcomes. Further adequately powered trials, in people of all ages, of prophylactic platelet transfusions compared with no transfusion, other alternative treatments, and considering different platelet thresholds prior to planned and emergency surgical procedures are required. Future trials should include major surgery and report on bleeding, adverse effects, mortality (as a long-term outcome) after surgery, duration of hospital stay and quality of life measures.

Prophylactic platelet transfusions prior to surgery for people with a low platelet count

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To determine the clinical effectiveness and safety of prophylactic platelet transfusions prior to surgery for people with a low platelet count or platelet dysfunction (inherited or acquired).