Massive blood transfusion in the elective surgical setting

Inferior Vena Cava Volume Is an Independent Predictor of Massive Transfusion in Patients With Trauma

OBJECTIVES

Early adequate resuscitation of patients with trauma is crucial in preventing shock and early mortality. Thus, we aimed to determine the performance of the inferior vena cava (IVC) volume and other risk factors and scores in predicting massive transfusion and mortality.

METHODS

We included all patients with trauma who underwent computed tomography (CT) scan of the torso, which included the abdominal area, in our emergency department (ED) from January 2014 to January 2017. We calculated the 3-dimensional IVC volume from the left renal vein to the IVC bifurcation. The primary outcome was the performance of IVC volume in predicting massive transfusion, and the secondary outcome was the performance of IVC volume in predicting 24-hour and 30-day in-hospital mortality.

RESULTS

Among the 236 patients with trauma, 7.6% received massive transfusions. The IVC volume and revised trauma score (RTS) were independent predictors of massive transfusion (adjusted odds ratio [OR]: 0.79 vs 1.86, 95% confidence interval [CI], 0.71-0.89 vs 1.4-2.47, respectively). Both parameters showed the good area under the curve (AUC) for the prediction of massive transfusion (adjusted AUC: 0.83 and 0.82, 95% CI, 0.74-0.92 vs 0.72-0.93, respectively). Patients with a large IVC volume (fourth quartile) were less likely to receive massive transfusion than those with a small IVC volume (first quartile, ≥28.29 mL: 0% vs <15.08 mL: 20.3%, OR: 0.13, 95% CI, 0.03-0.66).

CONCLUSIONS

The volume of IVC measured on CT scan and RTS are independent predictors of massive transfusion in patients with trauma in the ED.

Anaesthetic challenges for pelvic reconstruction with custom three-dimensional-printed titanium implants: A retrospective cohort study

Custom 3D printed titanium implant pelvic reconstructive surgery was implemented as a novel technique at our institutions in the last five years. It provided an option for pelvic bone malignancy patients who were previously deemed unsuitable for re-implantation of irradiated resected bone segments, as well as in revision total hip arthroplasty associated with excessive acetabular bone loss. A retrospective cohort study of the anaesthetic management of patients who underwent pelvic reconstructive surgery using custom 3D printed titanium implants from August 2013 to July 2018 was conducted. Twenty-seven patients were included in the study; 23 patients completed single-stage procedures with a mean (standard deviation) duration of surgery of 7.5 (3.3) hours (median 6.8, range 3.0–15.8 hours), and mean intraoperative blood loss of 5400 (3100) mL (median 6000, range 1400–10,000 mL). Surgery involving the sacrum ( n = 7) was associated with longer intensive care stay, longer total length of hospital stay and, in three cases, unplanned two-stage procedures. The twenty procedures not involving the sacrum were successfully completed in a single stage.

The major anaesthetic challenges included massive blood loss, prolonged surgery, interventions to prevent calf compartment syndrome, and perioperative thromboembolism. Preoperative pelvic radiotherapy, malignant tumours, and procedures involving the sacrum were associated with massive intraoperative blood loss and more prolonged surgery.

Quality Assessment of Established and Emerging Blood Components for Transfusion

Blood is donated either as whole blood, with subsequent component processing, or through the use of apheresis devices that extract one or more components and return the rest of the donation to the donor. Blood component therapy supplanted whole blood transfusion in industrialized countries in the middle of the twentieth century and remains the standard of care for the majority of patients receiving a transfusion. Traditionally, blood has been processed into three main blood products: red blood cell concentrates; platelet concentrates; and transfusable plasma. Ensuring that these products are of high quality and that they deliver their intended benefits to patients throughout their shelf-life is a complex task. Further complexity has been added with the development of products stored under nonstandard conditions or subjected to additional manufacturing steps (e.g., cryopreserved platelets, irradiated red cells, and lyophilized plasma). Here we review established and emerging methodologies for assessing blood product quality and address controversies and uncertainties in this thriving and active field of investigation.

Characteristics and Outcomes of Blood Product Transfusion During Critical Care Transport

BACKGROUND

Civilian out-of-hospital transfusions have not been adequately studied. This study seeks to characterize patients receiving out-of-hospital blood product transfusion during critical care transport.

STUDY DESIGN AND METHODS

We studied patients transported by a regional critical care air-medical service who received blood products during transport. This service carries two units of uncrossmatched packed Red Blood Cells (pRBCs) on every transport in addition to blood obtained from referring facilities. The pRBC are administered according to a protocol for the treatment of hemorrhagic shock or based on medical command physician order. Transfusion amount was categorized into three groups based on the volume transfused (<350 mL, 350-700 mL, >700 mL). The association between prehospital transfusion and in-hospital outcomes (mortality, subsequent blood transfusion and emergent surgery) was estimated using logistic regression models, controlling for age, first systolic blood pressure, first heart rate, Glasgow Coma Score, time of transfer, and length of hospital admission.

RESULTS

Among the 1,440 critical care transports with transfusions examined, 81% were for medical patients, being gastrointestinal hemorrhage the most common indication (26%, CI 24-28%). pRBC transfusions were associated with emergent surgery (OR = 1.81, 95% CI = 1.31-2.52) and in-hospital transfusions (OR = 2.00, 95% CI = 1.46-2.76). Those with transfusions >700 mL were associated with emergent surgery (OR = 1.79, 95% CI = 1.10-2.92) and mortality (OR = 2.11; 95% CI = 1.21-3.69).

CONCLUSIONS

In this sample, the majority of patients receiving blood products during air-medical transport were transfused for medic conditions; gastrointestinal hemorrhage was the most common chief complaint. The pRBC transfusions were associated with emergent surgery and in-hospital transfusion. Transfusions of >700 mL were associated with mortality.

Risk Factors for Postoperative Fibrinogen Deficiency after Surgical Removal of Intracranial Tumors

Higher levels of fibrinogen, a critical element in hemostasis, are associated with increased postoperative survival rates, especially for patients with massive operative blood loss. Fibrinogen deficiency after surgical management of intracranial tumors may result in postoperative intracranial bleeding and severely worsen patient outcomes. However, no previous studies have systematically identified factors associated with postoperative fibrinogen deficiency. In this study, we retrospectively analyzed data from patients who underwent surgical removal of intracranial tumors in Beijing Tiantan Hospital date from 1/1/2013to12/31/2013. The present study found that patients with postoperative fibrinogen deficiency experienced more operative blood loss and a higher rate of postoperative intracranial hematoma, and they were given more blood transfusions, more plasma transfusions, and were administered larger doses of hemocoagulase compared with patients without postoperative fibrinogen deficiency. Likewise, patients with postoperative fibrinogen deficiency had poorer extended Glasgow Outcome Scale (GOSe), longer hospital stays, and greater hospital expenses than patients without postoperative fibrinogen deficiency. Further, we assessed a comprehensive set of risk factors associated with postoperative fibrinogen deficiency via multiple linear regression. We found that body mass index (BMI), the occurrence of postoperative intracranial hematoma, and administration of hemocoagulasewere positively associated with preoperative-to-postoperative plasma fibrinogen consumption; presenting with a malignant tumor was negatively associated with fibrinogen consumption. Contrary to what might be expected, intraoperative blood loss, the need for blood transfusion, and the need for plasma transfusion were not associated with plasma fibrinogen consumption. Considering our findings together, we concluded that postoperative fibrinogen deficiency is closely associated with postoperative bleeding and poor outcomes and merits careful attention. Practitioners should monitor plasma fibrinogen levels in patients with risk factors for postoperative fibrinogen deficiency. In addition, postoperative fibrinogen deficiency should be remediated as soon as possible to reduce postoperative bleeding, especially when postoperative bleeding is confirmed.

[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.

Safety of fibrinogen concentrate: analysis of more than 27 years of pharmacovigilance data

Fibrinogen concentrate use as a haemostatic agent has been increasingly explored. This study evaluates spontaneous reports of potential adverse drug reactions (ADRs) that occurred during postmarketing pharmacovigilance of Haemocomplettan P/RiaSTAP, and reviews published safety data. This descriptive study analysed postmarketing safety reports recorded in the CSL Behring pharmacovigilance database from January 1986 to December 2013. A literature review of clinical studies published during the same period was performed. Commercial data indicated that 2,611,294 g of fibrinogen concentrate were distributed over the pharmacovigilance period, corresponding to 652,824 standard doses of 4 g each, across a range of clinical settings and indications. A total of 383 ADRs in 106 cases were reported (approximately 1 per 24,600 g or 6,200 standard doses). Events of special interest included possible hypersensitivity reactions in 20 cases (1 per 130,600 g or 32,600 doses), possible thromboembolic events in 28 cases (1 per 93,300 g or 23,300 doses), and suspected virus transmission in 21 cases (1 per 124,300 g or 31,000 doses). One virus transmission case could not be analysed due to insufficient data; for all other cases, a causal relationship was assessed as unlikely due to negative polymerase chain reaction tests and/or alternative explanations. The published literature revealed a similar safety profile. In conclusion, underreporting of ADRs is a known limitation of pharmacovigilance. However, the present assessment indicates that fibrinogen concentrate is administered across a range of indications, with few ADRs and a low thromboembolic event rate. Overall, fibrinogen concentrate showed a promising safety profile.

Usefulness of standard plasma coagulation tests in the management of perioperative coagulopathic bleeding: is there any evidence?

Standard laboratory coagulation tests (SLTs) such as prothrombin time/international normalized ratio or partial thromboplastin time are frequently used to assess coagulopathy and to guide haemostatic interventions. However, this has been challenged by numerous reports, including the current European guidelines for perioperative bleeding management, which question the utility and reliability of SLTs in this setting. Furthermore, the arbitrary definition of coagulopathy (i.e. SLTs are prolonged by more than 1.5-fold) has been questioned. The present study aims to review the evidence for the usefulness of SLTs to assess coagulopathy and to guide bleeding management in the perioperative and massive bleeding setting. Medline was searched for investigations using results of SLTs as a means to determine coagulopathy or to guide bleeding management, and the outcomes (i.e. blood loss, transfusion requirements, mortality) were reported. A total of 11 guidelines for management of massive bleeding or perioperative bleeding and 64 studies investigating the usefulness of SLTs in this setting were identified and were included for final data synthesis. Referenced evidence for the usefulness of SLTs was found in only three prospective trials, investigating a total of 108 patients (whereby microvascular bleeding was a rare finding). Furthermore, no data from randomized controlled trials support the use of SLTs. In contrast, numerous investigations have challenged the reliability of SLTs to assess coagulopathy or guide bleeding management. There is actually no sound evidence from well-designed studies that confirm the usefulness of SLTs for diagnosis of coagulopathy or to guide haemostatic therapy.

Effect of haematocrit on fibrin-based clot firmness in the FIBTEM test

BACKGROUND

Point-of-care thromboelastometry (ROTEM(®)) can be used to assess coagulation in whole blood. In the ROTEM(®) FIBTEM test, cytochalasin D eliminates the contribution of platelets to the whole blood clot; hence, only the remaining elements, including fibrinogen/fibrin, red blood cells and factor XIII, contribute to clot strength. We investigated the relationships between FIBTEM maximum clot firmness (MCF), whole blood fibrinogen concentration and plasma fibrinogen concentration to determine the impact of haematocrit on these parameters during cardiac surgery.

MATERIALS AND METHODS

The relationships between FIBTEM MCF and both whole blood fibrinogen concentration and plasma fibrinogen concentration (Clauss assay) were evaluated pre-operatively and after cardiopulmonary bypass/protamine administration in haematocrit-based subgroups.

RESULTS

The study included 157 patients. The correlation coefficient rho between FIBTEM MCF and plasma fibrinogen concentration was 0.68 at baseline and 0.70 after protamine, while that between FIBTEM MCF and whole blood fibrinogen concentration was 0.74 at baseline and 0.72 after protamine (all P <0.001). In subgroup analyses based on haematocrit levels, pre-operative FIBTEM MCF and whole blood fibrinogen concentration were both significantly higher (P <0.05) for the lowest haematocrit subgroup, but plasma fibrinogen concentration was similar in all groups. After protamine, no significant differences were observed between the lowest haematocrit group and the other groups for any of the three parameters.

CONCLUSIONS

The effect of haematocrit on blood clotting is not reflected by plasma fibrinogen concentration, in contrast to FIBTEM MCF which incorporates the contribution of haematocrit to whole blood clot firmness. This effect does, however, appear to be negligible in haemodiluted patients.

The US military experience with fresh whole blood during the conflicts in Iraq and Afghanistan

Since its introduction in the early part of the last century, fresh whole blood (FWB) has been used by the US military as a battlefield expedient resuscitation method, even after the development of component therapy in the 1960s. In the recent conflicts in Iraq and Afghanistan, FWB was used once more, often collected in the setting of a walking blood bank (WBB). Considerable research and opinion from military circles has cited these experiences and sparked renewed interest in FWB as an effective resuscitation tool in the setting of trauma. Despite efforts by the US military to improve the effectiveness and safety of FWB through a series of widely published guidelines, transfusion transmitted infections (TTI) remain a vexing challenge. These experiences in Iraq and Afghanistan will help inform a larger discussion regarding the reintroduction of FWB in civilian trauma resuscitation.

[Management of bleeding disorders in intensive care medicine]

Bleeding disorders are frequent in intensive care medicine, the most common form being acquired. Trauma, gastrointestinal bleeding, liver failure, hematologic malignancies, and adverse drug reactions play an important role. Moderate to severe hereditary bleeding disorders are usually known prior to the acute disease state, while mild hereditary forms may manifest for the first time in association with the acute stress condition. Generally, proper history taking and structured observation are decisive in order to conduct an appropriate diagnostic workup and initiate logical hemostatic management. One cannot always wait for laboratory results during continuous blood loss or conditions such as hypothermia and acidosis. In such cases, pathophysiological extrapolation of expected hemostatic disturbances is essential for timely hemostatic management.

Crisis checklists for the operating room: development and pilot testing

BACKGROUND

Because operating room crises are rare events, failure to adhere to critical management steps is common. We sought to develop and pilot a tool to improve adherence to lifesaving measures during operating room crises.

STUDY DESIGN

We identified 12 of the most frequently occurring operating room crises and corresponding evidence-based metrics of essential care for each (46 total process measures). We developed checklists for each crisis based on a previously defined method, which included literature review, multidisciplinary expert consultation, and simulation. After development, 2 operating room teams (11 participants) were each exposed to 8 simulations with random assignment to checklist use or working from memory alone. Each team managed 4 simulations with a checklist available and 4 without. One of the primary outcomes measured through video review was failure to adhere to essential processes of care. Participants were surveyed for perceptions of checklist use and realism of the scenarios.

RESULTS

Checklist use resulted in a 6-fold reduction in failure of adherence to critical steps in management for 8 scenarios with 2 pilot teams. These results held in multivariate analysis accounting for clustering within teams and adjusting for learning or fatigue effects (11 of 46 failures without the checklist vs 2 of 46 failures with the checklist; adjusted relative risk = 0.15, 95% CI, 0.04-0.60; p = 0.007). All participants rated the overall quality of the checklists and scenarios to be higher than average or excellent.

CONCLUSIONS

Checklist use can improve safety and management in operating room crises. These findings warrant broader evaluation, including in clinical settings.

Trends in transfusion of trauma victims--evaluation of changes in clinical practice

Background

The present study was performed to compare blood product consumption and clinical results in consecutive, unselected trauma patients during the first 6 months of year 2002, 2004 and 2007.

Methods

Clinical data, blood product consumption, lowest haemoglobin values on day 1-10 after admission, and 30-day mortality were extracted from in-hospital trauma registry and the blood bank data base. The subpopulation of massively transfused patients was identified and analysed separately.

Results

The total number of admitted trauma patients increased by 48% from 2002 to 2007, but the clinical data remained essentially unchanged. The mean number of erythrocyte units given day 1-10 decreased insignificantly from 9.4 in 2002 to 6.8 in 2007. New Injury Severity Score (NISS) increased in transfused and massively transfused patients, but not significantly. The number of patients transfused with plasma increased and the mean ratio of erythrocyte to plasma units transfused decreased by about 50%. The mean haemoglobin value in transfused patients on day 2 after admittance was significantly lower in 2007 than in 2002, while that on day 10 was significantly higher in 2007 than in 2002 and 2004. There was no change of 30-day survival from 2002 to 2007.

Conclusions

Significant changes of transfusion practice occurred during the past decade, probably as a result of increased focus on haemostasis and more precise criteria for transfusion. Despite a lower consumption of erythrocytes in 2007 than in 2002 and 2004, the mean haemoglobin level of transfused patients was higher on day 10 in 2007. The low number of transfused patients in this material makes evaluation of effect on survival difficult. Larger studies with strict control of all influencing factors are needed.

Principles of hemostasis in children: models and maturation

Hemostasis is an active process regulating the formation and dissolution of fibrin clot to preserve vascular integrity. The different phases of hemostasis are coordinated so that effective clotting occurs only at the site of vascular injury while maintaining blood flow in other parts of the circulation. Procoagulant processes culminate in thrombin generation and fibrin clot formation to protect the vasculature against uncontrolled bleeding after injury. Conversely, anticoagulant processes limit clot extension to unaffected portions of the vasculature. Lastly, fibrinolysis is responsible for clot dissolution once tissue repair and regeneration permit the return of normal blood flow. A precise and delicate interplay exists among these processes to ensure normal hemostasis. The hemostatic system is incompletely developed at birth and matures throughout infancy. Both full-term and preterm neonates are born with low levels of most procoagulant proteins including all the contact activation factors and vitamin K-dependent factors. Similarly, levels of the major anticoagulant proteins are low at birth. Although often characterized as 'immature', the neonatal hemostatic system is nevertheless functionally balanced with no tendency toward coagulopathy or thrombosis. In this article, we will review the current models of hemostasis and the maturation of the hemostatic system. Our goal is to help clinicians gain a better understanding of the actions of procoagulant agents and of the disruptive effects of serious systemic illnesses on the precarious hemostatic balance of infants.

Lack of effect of unrefrigerated young whole blood transfusion on patient outcomes after massive transfusion in a civilian setting

BACKGROUND

Warm fresh whole blood has been advocated for critical bleeding in the military setting. This study assessed whether unrefrigerated young whole blood transfusion, from donation to transfusion less than 24 hours, could reduce mortality of patients with critical bleeding in a civilian setting.

STUDY DESIGN AND METHODS

A linked data cohort study was conducted on a total of 353 consecutive patients requiring massive transfusion, defined as 10 units or more of red blood cells or whole blood transfusion within 24 hours, in a quaternary health care center in Australia.

RESULTS

Of the 353 patients with massive blood transfusion in the study, 77 received unrefrigerated young whole blood transfusion (mean, 4.0 units; interquartile range, 2-6). The diagnosis, severity of acute illness, age, sex, and ABO blood group were not significantly different between the patients who received unrefrigerated young whole blood and those who did not. Unrefrigerated young whole blood transfusions were associated with a slightly improved coagulation profile (lowest fibrinogen concentrations 1.7g/L vs. 1.4g/L, p=0.006; worst international normalization ratio, 2.4 vs. 2.8, p=0.05) but did not reduce the total utilization of allogeneic blood products and subsequent use of recombinant Factor VIIa (27% vs. 22%, p=0.358). Thirty-day mortality and 8-year survival after hospital discharge (hazard ratio, 1.05; 95% confidence interval, 0.41-2.65; p=0.93) were also not different after the use of unrefrigerated young whole blood transfusion.

CONCLUSIONS

Unrefrigerated young whole blood transfusion was not associated with a reduced mortality of patients requiring massive transfusion in a civilian setting when other blood products were readily available.

Management of post-partum haemorrhage

Management of post-partum haemorrhage (PPH) involves the treatment of uterine atony, evacuation of retained placenta or placental fragments, surgery due to uterine or birth canal trauma, balloon tamponade, effective volume replacement and transfusion therapy, and occasionally, selective arterial embolization. This article aims at introducing pregnancy- and haemorrhage-induced changes in coagulation and fibrinolysis and their relevant compensatory mechanisms, volume replacement therapy, optimal transfusion of blood products, and coagulation factor concentrates, and briefly cell salvage, management of uterine atony, surgical interventions, and selective arterial embolization. Special attention, respective management, and follow-up are required in women with bleeding disorders, such as von Willebrand disease, carriers of haemophilia A or B, and rare coagulation factor deficiencies. We also provide a proposal for practical instructions in the treatment of PPH.

Correction of coagulation in dilutional coagulopathy: use of kinetic and capacitive coagulation assays to improve hemostasis

The management of dilutional coagulopathy due to fluid infusion and massive blood loss is a topic that deserves a biochemical approach. In this review article, we provide an overview of current guidelines and recommendations on diagnosis and on management of transfusion in acquired coagulopathy. We discuss the biochemical differences between kinetic clotting assays (clotting times) and new capacitive coagulation measurements that provide time-dependent information on thrombin generation and fibrin clot formation. The available evidence suggests that a combination of assay types is required for evaluating new transfusion protocols aimed to optimize hemostasis and stop bleeding. Although there is current consensus on the application of fresh frozen plasma to revert coagulopathy, factor concentrates may appear to be useful in the future.

Massive transfusion: new insights

Massive transfusion (MT) is used for the treatment of uncontrolled hemorrhage. Earlier definitive control of life-threatening hemorrhage has significantly improved patient outcomes, but MT is still required. A number of recent advances in the area of MT have emerged, including the use of "hypotensive" or "delayed" resuscitation for victims of penetrating trauma before hemorrhage is controlled and "hemostatic resuscitation" with increased use of plasma and platelet transfusions in an attempt to maintain coagulation. These advances include the earlier use of hemostatic blood products (plasma, platelets, and cryoprecipitate), recombinant factor VIIa as an adjunct to the treatment of dilutional and consumptive coagulopathy, and a reduction in the use of isotonic crystalloid resuscitation. MT protocols have been developed to simplify and standardize transfusion practices. The authors of recent studies have advocated a 1:1:1 ratio of packed RBCs to fresh frozen plasma to platelet transfusions in patients requiring MT to avoid dilutional and consumptive coagulopathy and thrombocytopenia, and this has been associated with decreased mortality in recent reports from combat and civilian trauma. Earlier assessment of the exact nature of abnormalities in hemostasis has also been advocated to direct specific component and pharmacologic therapy to restore hemostasis, particularly in the determination of ongoing fibrinolysis.

Diagnosis and treatment of peripartum bleeding

Severe peripartum hemorrhage (PPH) contributes to maternal morbidity and mortality and is one of the most frequent emergencies in obstetrics, occurring at a prevalence of 0.5-5.0%. Detection of antepartum risk factors is essential in order to implement preventive measures. Proper training of obstetric staff and publication of recommendations and guidelines can effectively reduce the frequency of PPH and its resulting morbidity and mortality. Therefore, an interdisciplinary expert committee was formed, with members from Germany, Austria, and Switzerland, to summarize recent scientific findings. An up-to-date presentation of the importance of embolization and of the diagnosis of coagulopathy in PPH is provided. Furthermore, the committee recommends changes in the management of PPH including new surgical options and the off-label use of recombinant factor VIIa.

The surgical application of point-of-care haemostasis and platelet function testing

Background

Disordered coagulation complicates many diseases and their treatments, often predisposing to haemorrhage. Conversely, patients with cardiovascular disease who demonstrate antiplatelet resistance may be at increased thromboembolic risk. Prompt identification of these patients facilitates optimization of haemostatic dysfunction. Point-of-care (POC) tests are performed ‘near patient’ to provide a rapid assessment of haemostasis and platelet function.

Methods

This article reviews situations in which POC tests may guide surgical practice. Their limitations and potential developments are discussed. The paper is based on a Medline and PubMed search for English language articles on POC haemostasis and platelet function testing in surgical practice.

Results

POC tests identifying perioperative bleeding tendency are already widely used in cardiovascular and hepatic surgery. They are associated with reduced blood loss and transfusion requirements. POC tests to identify thrombotic predisposition are able to determine antiplatelet resistance, predicting thromboembolic risk. So far, however, these tests remain research tools.

Conclusion

POC haemostasis testing is a growing field in surgical practice. Such testing can be correlated with improved clinical outcome.

[Determination of fibrin glue with antibiotics on collagen production in colon anastomosis]

BACKGROUND/AIM

Fibrin glue is used as a matrix for local application of antibiotics. The aim of this study was to determine whether application of fibrin glue in combination with antibiotics can strengthen collagen production, prevent dehiscence of colon anastomoses due to infection, and reduce frequency of mortality and morbidity comparing to the control group and the group with fibrin glue application.

METHODS

The adult male Wistar rats divided into three groups were used in the experiment. The group 1 was the control one (after partial colon resection, colonic anastomoses performed were not treated), while to the group 2 and the group 3 were applied fibrin glue and fibrin glue with antibiotics (clindamycin and ceftriaxon) on the site of anastomoses, respectively. Quality of colonic anastomoses were estimated by means of determination of collagen (L-hydroxyproline) amount in the collon wall with anastomoses and histological analysis of this colon segment using light and electronic microscope on the days 5, 7 and 13 postoperatively.

RESULTS

The highest morbidity rate was registered in the group 1 (30%), then in the group 2 (13.3%) and the lowest one in the group 3 (3.33%; p < 0.05 vs group 1). Mortality rate was significantly higher in the group 1 than in the group 3 (20% and 0%, respectively; p < 0.05). In the postoperative course, the highest concentrations of collagen in the colon wall on the site of anastomoses, which was confirmed by both light and electronic microscopy, were found in the group 3.

CONCLUSION

The application of fibrin glue with antibiotics on colon anastomoses reduces the number of dehiscence, provides good mechanical protection and shorten the time of anastomoses healing.

Hemostatic Changes After Crystalloid or Colloid Fluid Administration During Major Orthopedic Surgery: The Role of Fibrinogen Administration

BACKGROUND

To explore whether disturbed fibrin polymerization is the main problem underlying dilutional coagulopathy and can be reversed by fibrinogen administration, we conducted a prospective study using modified thrombelastography (ROTEM).

METHODS

Sixty-six orthopedic patients randomly received modified gelatin solution, hydroxyethyl starch 130/0.4, or exclusively Ringer lactate solution. ROTEM analysis was performed, concentrations of coagulation factors and markers of thrombin generation were measured. Fibrinogen concentrate (Hemocomplettan) was administered (30 mg/kg) when thrombelastographically measured fibrinogen polymerization was critically decreased.

RESULTS

The alpha angle, clot firmness, and fibrinogen polymerization (median [min to max]) significantly decreased in the patients receiving hydroxyethyl starch (area under the curve minus baseline (-5 [-9 to -2]), followed by gelatin solution (-3 [-8 to 0]), with the least reductions seen for Ringer lactate solution (-2 [- 4 to 1]) (colloids versus Ringer lactate P < 0.0001). Thirteen patients in the colloid groups but none in the Ringer lactate group needed fibrinogen concentrate to maintain borderline clot firmness. Activity of FVII, FVIII, FIX, and von Willebrand ristocetin activity decreased significantly with colloids. Thrombelastographically measured coagulation time, molecular markers of thrombin generation, and activity of all other coagulation factors were comparable in all groups.

CONCLUSION

Disturbance of fibrinogen/fibrin polymerization is the primary problem triggering dilutional coagulopathy during major orthopedic surgery. The magnitude of clot firmness reduction is determined by the type of fluid used, with hydroxyethyl starch showing the most pronounced effects. These undesirable effects of intravascular volume therapy can be reversed by increasing fibrinogen concentration by administering fibrinogen concentrate, even during continuing blood loss and intravascular volume replacement.

[Massive hemorrhage and mechanisms of coagulopathy in trauma]

Trauma is disease of the young, mainly affecting people between 15-40 years of age. Uncontrolled massive bleeding is the leading cause of early in-hospital mortality, within 48h of admission, and the second leading cause of prehospital death in victims of both military and civilian trauma, accounting for 40-45% of the total fatalities. Coagulopathy develops early after injury and is present in 25-36% of trauma victims upon admission to the emergency department. Coagulopathy correlates to the severity of trauma and is associated with an increased risk of mortality. The aim of this paper is to explain pathophysiology of developing coagulopathy in trauma. The coagulopathy in the trauma patient is complex and multifactorial. It includes: dilutional coagulopathy, hypothermia, acidosis, hyperfibrinolysis, anemia and consumption coagulopathy. When the patient develops the so called "lethal triad" of hypothermia, acidosis and coagulopathy, surgical restoration of vascular integrity may be insufficient to achieve a deffinitive control of blood loss and non-mechanical bleeding from small vessels, usually terminated by spontaneous coagulation, becomes a life-threatening condition.

Coagulation factor concentrates: past, present, and future

Clotting factor transfusions are vital for people with diseases such as haemophilia. In the 1970s and 1980s, transfusions with pooled plasma led to a devastatingly high number of recipients becoming infected with blood-borne pathogens such as HIV and hepatitis C. This epidemic triggered the development of virus-free factor concentrates through a combination of improved donor selection and screening, effective virucidal technologies, and recombinant protein expression biotechnology. There is now a wide range of recombinant factor concentrates, and an impressive safety record with respect to pathogen transmission. However, remaining therapeutic challenges include the potential threat of transmission of prions and other pathogens, the formation of inhibitory alloantibodies, and the international disparity that exists in product availability due to differences in licensure status as well as prohibitively high costs. In the future, it is likely that bioengineered recombinant proteins that have been modified to enhance pharmacokinetic properties or reduce immunogenicity, or both, will be used increasingly in clinical practice.

[Coagulopaty in associated with massive transfusion]

Massive hemorrhage is a formidable challenge for anesthesia care providers in the elective setting and poses even greater potential challenges in the trauma setting. In all this cases, the anesthesia care providers are faced with large-volume resuscitations that typically start with crystalloid and colloid and rapidly progress to blood and blood products. These large-volume replacement may cause coagulopathy, which can be difficult to manage in the setting of ongoing blood loss. Coagulopathy associated with massive transfusion is multifactorial event that results from hemodilution, hypothermia, the use of fractionated blood products and disseminated intravascular coagulation. Maintaining a normal body temperature is a first-line, effective strategy to improve hemostasis during massive transfusion. Treatment strategies include the maintenance of adequate tissue perfusion, the corection of anemia, and the use of hemostatic blood products.

Recombinant activated factor VII: current perspectives and Epworth experience

Recombinant factor VII was first developed for control and prevention of bleeding in haemophilia with antibodies to factor VIII and IX. Its efficacy in these situations is well established. Over recent years, the 'off-label' use of this substance has become more widespread in trauma, surgery and obstetric bleeding. Here we describe the mechanism of action of recombinant factor VII, review current literature of 'off-label' usage and our initial experience in surgical related cases of bleeding at Epworth Hospital.

Use of blood and blood products in trauma

According to the global study of the burden of disease, violence and accidental injury account for 12% of deaths worldwide; 30-40% of trauma mortality is attributable to haemorrhage. The highly complex haemostatic system is severely impaired as a result of haemorrhagic shock, acidosis, hypothermia, haemodilution, hyperfibrinolysis, and consumption of clotting factors. Thus it is important to prioritize the prevention of the development of coagulopathy. Timely transfusion of red blood cells and plasma products becomes essential to restore tissue oxygenation, support perfusion, and maintain the pool of active haemostatic factors. The limits to this strategy to compensate for the loss of blood and coagulation factors are discussed. In the absence of international guidelines, there is an ongoing debate about a generally accepted treatment algorithm, mass transfusion protocols, and adverse events that have been observed as a result of transfusion. Thus many recommendations are based upon expert opinion rather than on evidence. In this chapter we address key issues of transfusions of red blood cells and plasma products in the acute control of bleeding in traumatized patients.

Proactive administration of platelets and plasma for patients with a ruptured abdominal aortic aneurysm: evaluating a change in transfusion practice

BACKGROUND

Continued hemorrhage remains a major contributor of mortality in massively transfused patients and those who survive have a higher platelet (PLT) count and a shorter prothrombin time and activated partial thromboplastin time (APTT) than nonsurvivors. It was considered that early substitution with PLTs and fresh-frozen plasma (FFP) would prevent development of coagulopathy and thus improve survival.

STUDY DESIGN AND METHODS

Survival of patients undergoing surgery for a ruptured abdominal aortic aneurysm (rAAA) was compared after implementing a proactive transfusion therapy encompassing two pooled buffy-coat PLT concentrates (PBPCs) immediately when a rupture of the aorta was suspected and again 30 minutes before aortic unclamping together with FFP administered in a 1:1 ratio to the amount of red blood cells (RBCs) with that of a control group receiving transfusion therapy according to existing recommendations.

RESULTS

The intervention group (n = 50) had a higher PLT count at arrival at the intensive care unit compared to the control group (n = 82; 155 x 10(9)/L vs. 69 x 10(9)/L; p < 0.0001), shorter APTT (39 sec vs. 44 sec; p < 0.001), fewer postoperative transfusions (RBCs, 2 vs. 6; FFP, 2 vs. 4; and PBPCs, 0 vs. 1; p < 0.01), and a higher 30-day survival rate (66% vs. 44%; p = 0.02).

CONCLUSION

This study suggests that proactive administration of PLTs and FFP improves coagulation competence, reduces postoperative hemorrhage, and increases survival in massively bleeding rAAA patients.

Recombinant activated factor VII as an adjunctive therapy for bleeding control in severe trauma patients with coagulopathy: subgroup analysis from two randomized trials

Introduction

We conducted a post-hoc analysis on the effect of recombinant factor VIIa (rFVIIa) on coagulopathic patients from two randomized, placebo-controlled, double-blind trials of rFVIIa as an adjunctive therapy for bleeding in patients with severe trauma.

Methods

Blunt and penetrating trauma patients were randomly assigned to rFVIIa (200 + 100 + 100 μg/kg) at 0, 1, and 3 hours after transfusion of 8 units of red blood cells (RBCs) or to placebo. Subjects were monitored for 48 hours post-dosing and followed for 30 days. Coagulopathy was retrospectively defined as transfusion of fresh frozen plasma (FFP) (>1 unit of FFP per 4 units of RBCs), FFP in addition to whole blood, and transfusion of platelets and/or cryoprecipitate.

Results

Sixty rFVIIa-treated and 76 placebo subjects were retrospectively identified as being coagulopathic. No significant differences were noted in baseline characteristics. The rFVIIa-treated coagulopathic subgroup consumed significantly less blood product: RBC transfusion decreased by 2.6 units for the whole study population (P = 0.02) and by 3.5 units among patients surviving more than 48 hours (P < 0.001). Transfusion of FFP (1,400 versus 660 ml, P < 0.01), platelet (300 versus 100 ml, P = 0.01), and massive transfusions (29% versus 6%, P < 0.01) also dropped significantly. rFVIIa reduced multi-organ failure and/or acute respiratory distress syndrome in the coagulopathic patients (3% versus 20%, P = 0.004), whereas thromboembolic events were equally present in both groups (3% versus 4%, P = 1.00).

Conclusion

Coagulopathic trauma patients appear to derive particular benefit from early adjunctive rFVIIa therapy.

Nonsurgical treatment of major bleeding

Novel nonsurgical approaches to bleeding control offer hope for improved management of the critical trauma-related coagulopathy and diffuse bleeding that often typify major trauma and pose challenges to surgeons and anesthetists. Although surgical treatment is the cornerstone of bleeding control, in selected patients angiographic embolization is increasingly used early in patient care to successfully manage arterial bleeding attributable to blunt solid organ injury or posterior pelvic ring disruption. Coagulopathic derangements in trauma occur early and require avoidance or correction of acidosis and hypothermia. If bleeding cannot be stopped by these measures, adjunctive use of fibrinogen or recombinant activated factor VII (rFVIIa) have the potential to correct systemic coagulopathy associated with massive blood loss and its management.

Lessons Learned from Modern Military Surgery

The era of global terrorism and asymmetric warfare heralded by the September 11, 2001 attacks on the United States have blurred the traditional lines between civilian and military trauma. The lessons learned by physicians in the theaters of war, particularly regarding the response to mass casualties, blast and fragmentation injuries, and resuscitation of casualties in austere environments, likely resonate strongly with civilian trauma surgeons in the current era. The evolution of a streamlined trauma system in the theaters of operations, the introduction of an in-theater institution review board process, and dedicated personnel to collect combat casualty data have resulted in improved data capture and realtime, on-the-scene research.

[Procedure for critical nonsurgical bleeding]

The improvement of surgical and nonsurgical approaches to control bleeding offers new strategies for overcoming coagulopathy. Massive hemorrhage is usually caused by a combination of surgical and coagulopathic bleeding. Coagulopathy is multifactorial and results from the dilution and consumption of both platelets and coagulation factors and dysfunction of the coagulation system. Blood component therapy continues to be a mainstay for this coagulopathy-related bleeding. However, the transfusion of red blood cells has been shown to be associated with post-injury infection and multiple organ failure. Therefore it is crucial to develop a clear strategy for correcting coagulopathy, preventing exsanguination, and minimizing the need for blood transfusion.

Koagulopathie

Coagulopathy after trauma is a major cause for uncontrolled hemorrhage in trauma victims. Approximately 40% of trauma related deaths are attributed to or caused by exsanguination. Therefore the prevention of coagulopathy is regarded as the leading cause of avoidable death in these patients. Massive hemorrhage after trauma is usually caused by a combination of surgical and coagulopathic bleeding. Coagulopathic bleeding is multifactorial, including dilution and consumption of both platelets and coagulation factors, as well as dysfunction of the coagulation system. Because of the high mortality associated with hypothermia, acidosis and progressive coagulopathy, this vicious circle is often referred to as the lethal triad, potentially leading to exsanguination. To overcome this coagulopahty-related bleeding an empiric therapy is often instituted by replacing blood components. However, the use of transfusion of red blood cells has been shown to be associated with post-injury infection and multiple organ failure. In the management of mass bleeding it is therefore crucial to have a clear strategy to prevent coagulopathy and to minimize the need for blood transfusion.

Massive transfusion and coagulopathy: pathophysiology and implications for clinical management

PURPOSE

To review the pathophysiology of coagulopathy in massively transfused, adult and previously hemostatically competent patients in both elective surgical and trauma settings, and to recommend the most appropriate treatment strategies.

METHODS

Medline was searched for articles on "massive transfusion," "transfusion," "trauma," "surgery," "coagulopathy" and "hemostatic defects." A group of experts reviewed the findings.

PRINCIPAL FINDINGS

Coagulopathy will result from hemodilution, hypothermia, the use of fractionated blood products and disseminated intravascular coagulation. The clinical significance of the effects of hydroxyethyl starch solutions on hemostasis remains unclear. Maintaining a normal body temperature is a first-line, effective strategy to improve hemostasis during massive transfusion. Red cells play an important role in coagulation and hematocrits higher than 30% may be required to sustain hemostasis. In elective surgery patients, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. In trauma patients, tissue trauma, shock, tissue anoxia and hypothermia contribute to the development of disseminated intravascular coagulation and microvascular bleeding. The use of platelets and/or fresh frozen plasma should depend on clinical judgment as well as the results of coagulation testing and should be used mainly to treat a clinical coagulopathy.

CONCLUSIONS

Coagulopathy associated with massive transfusion remains an important clinical problem. It is an intricate, multifactorial and multicellular event. Treatment strategies include the maintenance of adequate tissue perfusion, the correction of hypothermia and anemia, and the use of hemostatic blood products to correct microvascular bleeding.

Determinants of complications with recombinant factor VIIa for refractory blood loss in cardiac surgery

PURPOSE

Recombinant factor VIIa (rFVIIa) is being used for refractory, excessive blood loss (EBL) after cardiac surgery, but its safety for this indication is not known.

METHODS

The unadjusted and risk-adjusted adverse event (AE) rates were compared between 114 consecutive cardiac surgical patients who received rFVIIa for refractory EBL and 541 concurrent patients who developed EBL but did not receive rFVIIa. Similarly, timing of rFVIIa therapy was assessed by dichotomizing rFVIIa patients based on median number of red blood cell (RBC) units received before therapy. The measured AE was a composite of death, stroke, renal failure, myocardial infarction, and major vein thrombosis. For risk adjustment, logistic regression models for this outcome were constructed using known predictors of AEs.

RESULTS

The median RBC units transfused before rFVIIa therapy was eight. The AE rates in the untreated, early (< or = 8 U), and late (> 8 U) treated patients were 24% (129/541), 30% (20/66), and 60% (29/48). The risk-adjustment model included total RBC units, pump time, weaning difficulty, gender, weight, and age. The unadjusted and adjusted AE odds ratios (OR) in the treated vs untreated groups were 2.41 [confidence interval (CI) 1.58-3.67; P < 0.0001] and 1.04 (CI 0.60-1.81; P = 0.9). In the rFVIIa group, the adjusted AE OR was lower in the early treated group (OR 0.41; CI 0.18-0.92; P = 0.03).

CONCLUSION

In cardiac surgical patients with refractory hemorrhage, rFVIIa therapy is not associated with increased risk of AEs, and early treatment may be associated with better outcomes.

The Use of Fresh Whole Blood in Massive Transfusion

BACKGROUND

Most indications for whole blood transfusion are now well managed exclusively with blood component therapy, yet the use of fresh whole blood for resuscitating combat casualties has persisted in the U.S. military.

METHODS

Published descriptions of whole blood use in military and civilian settings were compared with use of whole blood at the 31st Combat Support Hospital (31st CSH) stationed in Baghdad in 2004-2005.

FINDINGS

Concerns about logistics, safety, and relative efficacy of whole blood versus component therapy have argued against the use of whole blood in most settings. However, military physicians have observed some distinct advantages in fresh warm whole blood over component therapy during the massive resuscitation of acidotic, hypothermic, and coagulopathic trauma patients. In this critical role, fresh whole blood was eventually incorporated as an adjunct into a novel whole-blood-based massive transfusion protocol.

CONCLUSIONS

Under extreme and austere circumstances, the risk:benefit ratio of whole blood transfusion favors its use. Fresh whole blood may, at times, be advantageous even when conventional component therapy is available.

Plasma and plasma products in the treatment of massive haemorrhage

Massive haemorrhage requires the use of plasma products when it is accompanied by a coagulopathy or when the more than one blood volume has been lost and intractable bleeding continues. The coagulopathy results from haemorrhagic shock, hypothermia, and activation, consumption and dilution of coagulation factors. Plasma products have a critical role in maintaining sufficient levels of coagulation proteins to ensure haemostasis can occur. Fresh frozen plasma is a source of all coagulation proteins and is required when the prothrombin time and activated partial thromboplastin time exceed 1.5 times the normal control. Cryoprecipitate is the plasma product of choice if fibrinogen, the most critical coagulation protein, is required rapidly and to maintain levels at >1g/L. Prothrombin complex concentrates, monocomponent factor therapy and fibrin sealants each have a role in specific clinical settings. Recombinant factor VIIa has now been shown to have a role in massive haemorrhage. Randomised controlled trials are currently underway to determine the optimal dose and timing of its administration. The physiology and management of the coagulation disturbance using plasma products in the massive haemorrhage of specific clinical situations are described.

The coagulopathy of massive transfusion

Recently, the Groupe d'Intérêt en Hémostase Périopératoire reviewed the pathophysiology of coagulopathy in massively transfused, adult and previously haemostatically competent patients in both elective surgical and trauma settings. In this article, we focus on our main observations. First, in most cases, the onset and severity of coagulopathy associated with massive transfusion differs depending on whether haemorrhage occurs as a result of trauma or elective surgery. In trauma patients, tissue trauma is uncontrolled, the interval between haemorrhage and treatment can vary widely, hypovolemia, shock and hypothermia are frequent, and coagulopathy is often related to the development of disseminated intravascular coagulation. Monitoring of haemostasis occurs late, when coagulopathy is installed, and treatment can be very difficult. In elective surgery patients, the situation remains controlled and, in most cases, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. Monitoring of haemostasis is ongoing and treatment is usually much simpler. Second, blood products have changed over time and this has affected the management of the bleeding patient. Contrary to the recommendations of studies published at a time when whole blood was readily available, the first line of treatment (at least in elective surgery patients) ought to be with fresh-frozen plasma to correct decreased levels of coagulation factors. The role of recombinant activated factor VII to treat bleeding that cannot be controlled by conventional measures remains to be clarified. Coagulopathy associated with massive transfusion remains an important clinical problem. Treatment strategies must be adapted to the context and to the blood products available. Nevertheless, the level of evidence supporting specific treatment options is low and more studies are required to guide our management of massively transfused patients.

Transfusion practice in massively bleeding patients: time for a change?

BACKGROUND AND OBJECTIVES

We identified some fatal cases where massively bleeding patients received inadequate transfusion therapy. The aim of this study was to review and evaluate the transfusion practice in acutely multitransfused patients.

MATERIALS AND METHODS

Patients receiving > 10 units of red blood cells (RBC) within 24 h of admission and 30 blood components within 7 days of admission were reviewed.

RESULTS

Thirty-nine patients were identified, 13 of whom were inadequately transfused (IT) and had a higher mortality (12/13) than adequately transfused (AT) patients 13/26 (P = 0.013). Ten of 13 IT patients developed a microvascular bleed compared to four of 26 in the AT group (P = 0.001) and had a lower platelet count upon arrival at the intensive care unit (40 x 10(9)/l vs. 80 x 10(9)/l, P = 0.024).

CONCLUSIONS

An early balanced transfusion therapy is vital in massively bleeding patients, and a pro-active approach from the blood bank is warranted. We have introduced an acute transfusion package (ATP) consisting of 5 RBC, 5 FFP and 2 PC units, indicated in massively bleeding patients, securing a balanced transfusion therapy.

Coagulopathy and blood component transfusion in trauma

Trauma is a serious global health problem, accounting for approximately one in 10 deaths worldwide. Uncontrollable bleeding accounts for 39% of trauma-related deaths and is the leading cause of potentially preventable death in patients with major trauma. While bleeding from vascular injury can usually be repaired surgically, coagulopathy-related bleeding is often more difficult to manage and may also mask the site of vascular injury. The causes of coagulopathy in patients with severe trauma are multifactorial, including consumption and dilution of platelets and coagulation factors, as well as dysfunction of platelets and the coagulation system. The interplay between hypothermia, acidosis and progressive coagulopathy, referred to as the 'lethal triad', often results in exsanguination. Current management of coagulopathy-related bleeding is based on blood component replacement therapy. However, there is a limit on the level of haemostasis that can be restored by replacement therapy. In addition, there is evidence that transfusion of red blood cells immediately after injury increases the incidence of post-injury infection and multiple organ failure. Strategies to prevent significant coagulopathy and to control critical bleeding effectively in the presence of coagulopathy may decrease the requirement for blood transfusion, thereby improving clinical outcome of patients with major trauma.

Guidelines for the use of recombinant activated factor VII (rFVIIa) in uncontrolled bleeding: a report by the Israeli Multidisciplinary rFVIIa Task Force

BACKGROUND

Recombinant activated factor VII (rFVIIa) has been approved by the U.S. Food and Drug Administration (FDA) for almost a decade for hemophilic patients with inhibitors. Its off-label use as a hemostatic agent in massive bleeding caused by a wide array of clinical scenarios is rapidly expanding. While evidence-based guidelines exist for rFVIIa treatment in hemophilia, none are available for its off-label use.

OBJECTIVES

The aim of this study is to develop expert recommendations for the use of rFVIIa in patients suffering from uncontrolled bleeding (with special emphasis on trauma) until randomized, controlled trials allow for the introduction of more established evidence-based guidelines.

METHODS

A multidisciplinary task force comprising representatives of the relevant National Medical Associations, experts from the Medical Corps of the Army, Ministry of Health and the Israel National Trauma Advisory Board was established in Israel. Recommendations were construed based on the analysis of the first 36 multi-trauma patients accumulated in the prospective national registry of the use of rFVIIa in trauma, and an extensive literature search consisting of published and prepublished controlled animal trials, case reports and series. The final consensus guidelines, together with the data of the first 36 trauma patients treated in Israel, are presented in this article.

RESULTS

Results of the first 36 trauma patients: The prolonged clotting assays [prothrombin time (PT) and partial thromboplastin time (PTT)] shortened significantly within minutes following administration of rFVIIa. Cessation of bleeding was achieved in 26 of 36 (72%) patients. Acidosis diminished the hemostatic effect of the drug, while hypothermia did not affect it. The survival rate of 61% (22/36) seems to be favorable compared with published series of similar, or less severe, trauma patients (range 30%-57%).

CONCLUSIONS

As a result of the lack of controlled trials, our guidelines should be considered as suggestive rather than conclusive. However, they provide a valuable tool for physicians using rFVIIa for the expanding off-label clinical uses.