Logistics of transfusion support for patients with massive hemorrhage

Optimizing systems to manage postpartum hemorrhage

Systems to optimize the management of postpartum hemorrhage must ensure timely diagnosis, rapid hemodynamic and hemostatic resuscitation, and prompt interventions to control the source of bleeding. None of these objectives can be effectively completed by a single clinician, and the management of postpartum hemorrhage requires a carefully coordinated interprofessional team. This article reviews systems designed to standardize hemorrhage diagnosis and response.

In Vivo Effects of Balanced Crystalloid or Gelatine Infusions on Functional Parameters of Coagulation and Fibrinolysis: A Prospective Randomized Crossover Study

Prudent administration of fluids helps restore or maintain hemodynamic stability in the setting of perioperative blood loss. However, fluids may arguably exacerbate the existing coagulopathy. We sought to investigate the influence of balanced crystalloid and synthetic gelatine infusions on coagulation and fibrinolysis in healthy volunteers. This prospective randomized crossover study included 25 males aged 18–30 years. Infusions performed included 20 mL/kg of a balanced crystalloid solution (Optilyte^®) or 20 mL/kg of gelatine 26.500 Da (Geloplasma^®) in a random order over a period of 2 weeks. Laboratory analysis included conventional coagulation parameters and rotational thromboelastometry (ROTEM) assays. We confirmed a decrease in fibrinogen concentration and the number of platelets, and prolongation of PT after infusions. Compared to baseline values, differences in the ROTEM assays’ results after infusions signified the decrease in coagulation factors and fibrinogen concentration, causing impaired fibrin polymerization and clot structure. The ROTEM indicator of clot lysis remained unaffected. In the case of both Optilyte^® and Geloplasma^®, the results suggested relevant dilution. Gelatine disrupted the process of clot formation more than balanced crystalloid. Infusions of both crystalloid and saline-free colloid solutions causing up to 30% blood dilution cause significant dilution of the coagulation factors, platelets, and fibrinogen. However, balanced crystalloid infusion provides less infusion-induced coagulopathy compared to gelatine.

How do I manage severe postpartum hemorrhage?

In the United States, postpartum hemorrhage (PPH) accounts for 4.6% of all maternal deaths and is responsible for major peripartum medical and surgical morbidity. Therefore, a national health priority is to ensure that women who experience severe PPH receive timely, appropriate, and effective treatment. In this article, we describe our system-wide approach for the planning and delivery of women with suspected placenta accreta spectrum disorder, a condition associated with life-threatening blood loss at the time of delivery. We also highlight current evidence related to transfusion decision making and hemostatic monitoring during active postpartum bleeding. Specifically, we describe how we activate and use the massive transfusion protocol to obtain sufficient volumes and types of blood products. We also describe how we use viscoelastic monitoring (thromboelastography) and standard laboratory tests to assess the maternal coagulation profile. Finally, we review the findings of recent studies examining the potential efficacy of tranexamic acid and fibrinogen concentrate as adjuncts for PPH prevention and treatment. We describe how we have incorporated these drugs into PPH treatment protocols at our institution.

National and International Guidelines for Patient Blood Management in Obstetrics: A Qualitative Review

In developed countries, rates of postpartum hemorrhage (PPH) requiring transfusion have been increasing. As a result, anesthesiologists are being increasingly called upon to assist with the management of patients with severe PPH. First responders, including anesthesiologists, may adopt Patient Blood Management (PBM) recommendations of national societies or other agencies. However, it is unclear whether national and international obstetric societies' PPH guidelines account for contemporary PBM practices. We performed a qualitative review of PBM recommendations published by the following national obstetric societies and international groups: the American College of Obstetricians and Gynecologists; The Royal College of Obstetricians and Gynecologists, United Kingdom; The Royal Australian and New Zealand College of Obstetricians and Gynecologists; The Society of Obstetricians and Gynecologists of Canada; an interdisciplinary group of experts from Austria, Germany, and Switzerland, an international multidisciplinary consensus group, and the French College of Gynaecologists and Obstetricians. We also reviewed a PPH bundle, published by The National Partnership for Maternal Safety. On the basis of our review, we identified important differences in national and international societies' recommendations for transfusion and PBM. In the light of PBM advances in the nonobstetric setting, obstetric societies should determine the applicability of these recommendations in the obstetric setting. Partnerships among medical, obstetric, and anesthetic societies may also help standardize transfusion and PBM guidelines in obstetrics.

Bleeding and damage control surgery

PURPOSE OF REVIEW

Bleeding is still a major cause of death in trauma patients. Damage control surgery is a strategy that aims to control bleeding and avoid secondary contamination of the cavity. This article checks the principles and indications of damage control surgery, bleeding management, and the role of the anesthesiologist in trauma context. The efficient treatment of severe trauma and exsanguinated patients includes a surgical approach to the patient performed as quickly as possible. Volemic resuscitation, hemostatic transfusion, prevention and/or treatment of coagulopathy, hypothermia, and acidosis are strategies that reduce bleeding, as well as permissive hypotension.

RECENT FINDINGS

Specialized literature shows us that the adoption of all of these principles along with reduced surgical time has led to a broader concept called damage control resuscitation.

SUMMARY

Damage control resuscitation is a treatment strategy in which the recovery of physiological variables is initially prioritized over anatomical variables and can be required in severe trauma patients.

Haemostasis monitored in stored red blood cells, plasma and platelet concentrates in the proportion of 4 : 4 : 1 diluted with crystalloids and colloids

The aim of this in-vitro study was to evaluate haemostasis analysed with thromboelastometry and blood gas and blood count variables, in stored blood components and the effects after dilution with Ringer[Combining Acute Accent]s acetate, albumin and hydroxyethyl starch (HES). Aliquots from stored red blood cells, plasma and platelet concentrates were mixed in the proportion of 4 : 4 : 1 and analysed with rotational thromboelastometry (ROTEM), blood count [haemoglobin (Hb), haematocrit, platelet count] and blood gas (pH, calcium, sodium, potassium, glucose levels). The blood mix was thereafter diluted 20 and 33% with Ringer's acetate, albumin or HES. The stored blood component mix in a ratio of 4 : 4 : 1 had a low pH (7.11 ± 0.03, mean ± standard deviation), nonmeasurable calcium level, and high concentrations of sodium, potassium and glucose but ROTEM curves within normal range after recalcification. With Ringer's acetate dilution, the ROTEM variables changed almost linearly with increasing dilution volume. When albumin was used in the 33% dilution, the clot firmness of the fibrin clot (FibTEM) was further reduced, and with HES dilution, there was a pronounced impairment. The stored blood mix had a low pH and calcium level, both of which might have a significant influence on the coagulation process but normal ROTEM curves after recalcification. Dilution with Ringer's acetate and albumin resulted in moderate deterioration, while dilution with HES showed severely impaired haemostasis.

Massive obstetric hemorrhage: Current approach to management

Massive obstetric hemorrhage is a major cause of maternal mortality and morbidity worldwide. It is defined (among others) as the loss of>2,500ml of blood, and is associated to a need for admission to critical care and/or hysterectomy. The relative hemodilution and high cardiac output found in normal pregnancy allows substantial bleeding before a drop in hemoglobin and/or hematocrit can be identified. Some comorbidities associated with pregnancy can contribute to the occurrence of catastrophic bleeding with consumption coagulopathy, which makes the situation even worse. Optimization, preparation, rational use of resources and protocolization of actions are often useful to improve outcomes in patients with postpartum hemorrhage. Using massive obstetric hemorrhage protocols is useful for facilitating rapid transfusion if needed, and can also be cost-effective. If hypofibrinogenemia during the bleeding episode is identified, early fibrinogen administration can be very useful. Other coagulation factors in addition to fibrinogen may be necessary during postpartum hemorrhage replacement measures in order to effectively correct coagulopathy. A hysterectomy is recommended if the medical and surgical measures prove ineffective.

Transfusion and coagulation management in major obstetric hemorrhage

PURPOSE OF REVIEW

Major obstetric hemorrhage is a leading cause of maternal morbidity and mortality. We will review transfusion strategies and the value of monitoring the maternal coagulation profile during severe obstetric hemorrhage.

RECENT FINDINGS

Epidemiologic studies indicate that rates of severe postpartum hemorrhage (PPH) in well resourced countries are increasing. Despite these increases, rates of transfusion in obstetrics are low (0.9-2.3%), and investigators have questioned whether a predelivery 'type and screen' is cost-effective for all obstetric patients. Instead, blood ordering protocols specific to obstetric patients can reduce unnecessary antibody testing. When severe PPH occurs, a massive transfusion protocol has attracted interest as a key therapeutic resource by ensuring sustained availability of blood products to the labor and delivery unit. During early postpartum bleeding, recent studies have shown that hypofibrinogenemia is an important predictor for the later development of severe PPH. Point-of-care technologies, such as thromboelastography and rotational thromboelastometry, can identify decreased fibrin clot quality during PPH, which correlate with low fibrinogen levels.

SUMMARY

A massive transfusion protocol provides a key resource in the management of severe PPH. However, future studies are needed to assess whether formula-driven vs. goal-directed transfusion therapy improves maternal outcomes in women with severe PPH.

What is new in the blood bank for trauma resuscitation

PURPOSE OF REVIEW

The aim of the present review was to describe recent changes in blood banking thinking, practice, and products that affect trauma care.

RECENT FINDINGS

Prompt balanced hemostatic resuscitation of major hemorrhage from trauma improves outcome and reduces blood use. New blood processes and products can help deliver appropriate doses of procoagulant plasma and platelets quicker and more safely. New processes include holding larger inventories of thawed plasma with risk of wastage and rapid plasma thawers. New products in the blood bank include group A or group A low-titer B thawed plasma and AB or A liquid (never-frozen) plasma for resuscitation, prepooled cultured whole blood-derived platelets in plasma, and prepooled cryoprecipitate in varying pool sizes. Single-donor apheresis or pooled whole blood-derived platelets in additive solution, designed to reduce plasma-related transfusion reactions, are also increasingly available but are not an appropriate blood component for hemorrhage control resuscitation because they reduce the total amount of administered plasma coagulation factors by 10%.

SUMMARY

Early initiation of balanced massive transfusion protocols leading to hemostatic resuscitation is lifesaving. Changing blood product availability and composition will lead to higher complexity of massive transfusion. It is critical that anesthesiologists understand the composition of the available new blood products to use them correctly.

Liquid plasma use during "super" massive transfusion protocol

BACKGROUND

A massive transfusion protocol (MTP) presents a logistical challenge for most blood banks and trauma centers. We compare the ratio of packed red blood cells (PRBC) and plasma transfused over serial time points in those requiring MTP (10-30 U PRBC/24 h) to those requiring "super" MTP (S-MTP; >30 U PRBC/24 h) and test the hypothesis that changes in allocation of blood products with use of readily transfusable liquid plasma (LP) improves the ratio of PRBC and plasma during S-MTP.

MATERIALS AND METHODS

All transfused trauma patients (n = 1305) from January 01, 2009-April, 03, 2015 were reviewed. PRBC:plasma ratio was compared for MTP (n = 277) and S-MTP (n = 61) patients, before and after the availability of LP at our institution. Data are reported as mean ± standard deviation or median (interquartile range).

RESULTS

Age was 41 ± 19 y, 52% blunt mechanism, injury severity score 32 ± 16, and 46.3% mortality. In 24 h, requirements were 17 (14) U PRBC and 10 (11) U plasma, with a PRBC:plasma of 1.6 (0.8). Within the first hour, PRBC:plasma for S-MTP versus MTP was 2.1:1 versus 1.7:1 (P = 0.017). With LP, S-MTP patients received significantly lower PRBC:plasma at the first hour (P < 0.001). Before institutional changes, PRBC:plasma positively correlated with PRBC transfused at hour 1 (r = 0.410, R(2) = 0.168, P < 0.001); after institutional changes and the advent of LP, there was no correlation (r = 0.177, R(2) = 0.031, P = 0.219).

CONCLUSIONS

Within the first hour of transfusion, units of PRBC transfused positively correlated with PRBC:plasma, and patients receiving S-MTP had higher PRBC:plasma than those receiving MTP. Changes in our institution's MTP protocol to include LP improved the early PRBC:plasma transfused in patients requiring S-MTP.

Management of traumatic haemorrhage--the US perspective

As compared with European practice, the American approach to resuscitation from traumatic haemorrhage de-emphasises pre-hospital interventions in favour of rapid transport to definitive care; limits initial surgical interventions under the damage control model; uses crystalloid as the initial fluid of choice; and follows an empiric 1:1:1 approach to transfusion with red cells, plasma and platelets in hemodynamically unstable and actively bleeding patients. The use of bedside visco-elastic testing to guide coagulation support is not as widespread as in Europe, while the early administration of tranexamic acid is more selective.

In vitro combinations of red blood cell, plasma and platelet components evaluated by thromboelastography

BACKGROUND

Thromboelastography is increasingly used to evaluate coagulation in massively bleeding patients. The aim of this study was to investigate how different combinations of blood components affect in vitro whole blood clotting measured by thromboelastography.

MATERIALS AND METHODS

Packed red blood cells, plasma and platelets from fresh and old blood components were mixed in vitro, in proportions of 4:4:1, 5:5:2, 8:4:1 and 2:1:0, and analysed with thromboelastography. For the ratio 4:4:1 the experiment was done at both 37 °C and 32 °C.

RESULTS

Thromboelastography curves were within normal reference values for the blood component proportions of 4:4:1 and 5:5:2. For 8:4:1, the angle and maximal amplitude were reduced below normal values, indicating low levels of fibrinogen and/or platelets. For the 2:1:0 proportion, all parameters were affected resulting in severely impaired in vitro clot formation. The reaction-time, reflecting the coagulation factor-dependent, initial clot formation, was slightly increased at a low temperature. Prolonged storage of the components did not affect the curve.

DISCUSSION

With the introduction of guidelines on the management of massive bleeding it is important to have tools for the assessment of the new protocols. In vitro evaluation of mixtures of packed red blood cells, plasma and platelets by thromboelastography may be relevant in the prediction of in vivo clot formation and haemostasis.

Alternatives to blood transfusion

The use of alternatives to allogeneic blood continues to rest on the principles that blood transfusions have inherent risks, associated costs, and affect the blood inventory available for health-care delivery. Increasing evidence exists of a fall in the use of blood because of associated costs and adverse outcomes, and suggests that the challenge for the use of alternatives to blood components will similarly be driven by costs and patient outcomes. Additionally, the risk-benefit profiles of alternatives to blood transfusion such as autologous blood procurement, erythropoiesis-stimulating agents, and haemostatic agents are under investigation. Nevertheless, the inherent risks of blood, along with the continued rise in blood costs are likely to favour the continued development and use of alternatives to blood transfusion. We summarise the current roles of alternatives to blood in the management of medical and surgical anaemias.

Concepts of blood transfusion in adults

Recent progress has been made in the identification and implementation of best transfusion practices on the basis of evidence-based clinical trials, published clinical practice guidelines, and process improvements for blood use and clinical patient outcomes. However, substantial variability persists in transfusion outcomes for patients in some clinical settings--eg, patients undergoing cardiothoracic surgery. This variability could be the result of insufficient understanding of published guidelines; different recommendations of medical societies, including the specification of a haemoglobin concentration threshold to use as a transfusion trigger; the value of haemoglobin as a surrogate indicator for transfusion benefit, even though only changes in concentration and not absolute red cell mass of haemoglobin can be identified; and disagreement about the validity of the level 1 evidence for clinical practice guidelines. Nevertheless, institutional experience and national databases suggest that a restrictive blood transfusion approach is being increasingly implemented as best practice.