Point Of Care Coagulation Testing Research Articles

Clues of incomplete reversal of heparin in cardiac surgery.

In our center, an unusual rate of patients had abnormalities of hemostasis in immediate postoperative period of cardiac surgery. Our objectives were to identify the cause of these sudden hemostasis abnormalities and to evaluate the performances of point of care coagulation testing. In this prospective and descriptive study, we included 33 consecutive patients undergoing elective cardiac surgery for 1month. Heparin-induced anticoagulation and calculation of the protamine dose were tested by the Hemostasis Management System Plus device (Medtronic, Minneapolis, MN, USA). Fifteen minutes after the end of the protamine infusion, activated clotting time (ACT), activated partial thromboplastin time and anti Xa activity were measured. In case of unusual clinical bleeding, a Quantra analysis (Stago, HemoSonics LLC, Charlottesville, VA) was added. Residual antiXa activity >0.2 IU/mL after neutralization was present in 44% of patients. Our investigation concluded incomplete heparin reversal. There was no association between cellular reinfusate and the presence of heparin. The unusual rate of hemostasis abnormalities was explained by a less efficient protamine reversal of heparin. ACT and Clot Time Ratio (CTR, Quantra system) correlated with AntiXa with Spearman's coefficients of 0.85 (p < .0001) and 0.95 (p = .0012), respectively. About ACT, a threshold of 150 seconds had a sensitivity of 85% [58-97] and a specificity of 85% [58-97%] for detection of AntiXa>0.2. For CTR, a threshold of 1.4 had a sensitivity of 67% [30-94] and a specificity of 100% [18-100]. The use of point of care coagulation testing is effective in detecting incomplete reversal of heparin.

Blood management in post-partum haemorrhage, including point of care coagulation tests

Postpartum haemorrhage (PPH) is the leading global cause of maternal mortality, and an important cause of morbidity and mortality in the UK. Management of PPH requires a patient centred team approach to ensure effective management. Early recognition is crucial, hence quantitative measurement of blood loss should be started as soon as bleeding is identified and continue throughout an evolving haemorrhage. Pregnancy is associated with haematological changes resulting in a pro-coagulant state. Blood management in PPH has moved away from the use of shock packs and fixed transfusion ratios. Most women are not initially coagulopathic and coagulopathy is uncommon in mild to moderate PPH, Practice has therefore moved towards goal directed transfusion of blood products informed by haematological investigations alongside clinical assessment. Fibrinogen tends to be the first coagulation factor to fall and Clauss fibrinogen is an important predictor of PPH severity. Transfusion of fibrinogen rich blood products such as cryoprecipitate and fibrinogen complex are more effective at rapidly increasing fibrinogen levels compared to FFP. Point of care (POC) coagulation tests such as rotational thromboelastometry (ROTEM) and thromboeslastography (TEG) allow rapid bedside assessment compared to traditional laboratory tests. Surrogate markers of fibrinogen from POC tests can be used to both predict severity of PPH and inform blood transfusion. There is growing evidence that POC coagulation tests can be used to safely guide blood management in PPH, with its use associated with lower transfusion rates and possibly improved clinical outcomes. Further multi-centre studies are required to clarify debate surrounding their use. In this review we discuss blood management in PPH, with a focus on recent evidence regarding assessment of coagulopathy and the use of blood products.

Референсные интервалы параметров ротационной тромбоэластометрии у беременных и родильниц: одноцентровое рандомизированное исследование

Введение: В последнее время стали востребованы интегральные тесты оценки системы гемостаза у женщин во время беременности, а также во время акушерских операций, связанных с кровотечением. В нашей стране отсутствуют работы по определению популяционных норм ротационной тромбоэластометрии (РОТЕМ) у беременных, рожениц и родильниц. Цель исследования: определить пределы референсных интервалов показателей РОТЕМ во время физиологически протекающей беременности и в раннем послеродовом периоде и провести корреляционный анализ со стандартными показателями коагулограммы. Материалы и методы: Обследовано 229 женщин Красноярского края, которые были поделены на 5 групп: небеременные (контроль), беременные II и III триместров, женщины раннего послеродового периода после операции кесарева сечения и естественных родов. Все женщины были сопоставимы по возрасту, индексу массы тела, сопутствующей патологии. Референсные интервалы рассчитывали либо через среднее и стандартное отклонение (для нормального распределения), либо через медиану и 2,5 и 97,5% перцентили (для ненормального распределения). Результаты: В процессе исследования подтвердилось, что во время беременности и в раннем послеродовом периоде происходят изменения в системе гемостаза в сторону гиперкоагуляции. Показатели ROTЕM у женщин в III триместре беременности и раннем послеродовом периоде существенно отличаются от показателей небеременных в популяции. У женщин после родов вне зависимости от способа родоразрешения различий между параметрами ROTЕM не установлено. Корреляция между параметрами ROTЕM и традиционными лабораторными тестами коагуляции выявила взаимосвязь между амплитудой плотности сгустка в тесте FIBTEM и уровнем фибриногена по Клаусу. Заключение: Представлены референсные интервалы параметров РОТЕМ у женщин Красноярского края. Найдена корреляция между параметрами РОТЭМ и уровнем фибриногена. Background: Recently, integral tests for hemostasis assessment in pregnant women as well as during obstetric surgery associated with bleeding have become popular. In our country, there are no studies of population norms for rotational thromboelastometry (ROTEM) in pregnant women, parturients and puerperants. Objectives: to identify reference intervals limits for ROTEM parameters during physiological pregnancy and in early postpartum period and to carry out correlation analysis with standard coagulogram parameters. Patients/Methods: We examined 229 women in Krasnoyarsk region; they were divided into 5 groups: nonpregnant (control), pregnant women in II and III trimesters, women in early postpartum period after cesarean section and after vaginal delivery. All women were comparable in age, body mass index, and concomitant pathology. Reference intervals were calculated either as the mean and standard deviation (for normal distribution), or as the median and 2.5 and 97.5% percentiles (for abnormal distribution). Results: The study confirmed hemostasis hypercoagulation changes during pregnancy and in early postpartum period. ROTEM parameters in women in III trimester of pregnancy and in early postpartum period differ significantly from those in non-pregnant women. Differences between ROTEM parameters in puerperants, regardless of the delivery method, not found. The correlation between ROTEM parameters and traditional laboratory coagulation tests revealed a relationship between clot density amplitude in FIBTEM test and Klaus fi brinogen level. Conclusions: Reference intervals of ROTEM parameters in women of Krasnoyarsk region are presented. A correlation was found between ROTEM parameters and fibrinogen level

Thromboelastometry and a hemostasis management system are most beneficial for guiding hemostatic therapy in cardiac surgery patients with a EuroSCORE II of ≥1.83%: a randomized controlled two-step trial.

We evaluated the efficacy of hemostatic therapy based on point-of-care (POC) testing in patients undergoing cardiac surgery. This was a single-institution, prospective, randomized, double-blinded study. In step 1, 90 patients scheduled for elective cardiac surgery underwent complete blood count and fibrinogen measurements at baseline, after cardiopulmonary bypass (CPB) initiation (CPB start), just after CPB end, and in the intensive care unit (ICU). In step 2, 72 patients scheduled for elective cardiac surgery underwent conventional laboratory coagulation tests (control group) or POC coagulation tests (POC group). Transfusions were prepared using the fibrinogen and platelet values at mainly "CPB start" for the control group, and using the ROTEM values at mainly "CPB end" for the POC group. Consequently, the step 2 patients were divided into high- and low-risk subgroups based on the EuroSCORE II by logistic regression analysis; transfusion data and bleeding volumes were compared between the control and POC groups within the high- and low-risk subgroups. In step 1, all blood components were significantly decreased at CPB start compared with baseline, and platelet and fibrinogen levels remained almost constant from CPB start to end. In step 2, the transfusion rates and perioperative bleeding volumes did not significantly differ between the control and POC groups. Subgroup analysis suggested that only the high-risk subgroup significantly differed regarding perioperative red blood cell transfusion and total bleeding volume in the ICU. POC testing is beneficial for cardiac surgery patients with a EuroSCORE II of ≥1.83%.

Point-of-Care diagnostics of coagulation in the management of bleeding and transfusion in trauma patients.

Trauma-associated bleeding and coagulopathy require timely identification, prevention, and effective treatment. The present review summarizes the recent literature around point-of-care (POC) coagulation tests, their usefulness in the management of trauma-induced coagulopathy (TIC), their impact on trauma patient outcomes, and the requirement of quality assurance. Best practice algorithms to manage TIC have been compiled in the 2019 European Guideline on the management of major bleeding and coagulopathy after trauma. Evidence supports the use of goal-directed approaches to manage TIC. POC coagulation tests can accelerate and tailor individualized therapies. Recent findings emphasize: the time sparing of POC tests in prehospital settings and the validity of POC measurements in extreme environments; the potential scalability of POC-guided TIC algorithms in burn injuries and the pediatric population; the need for careful considerations of strategies to monitor and reverse the effects of direct oral anticoagulants in major trauma. In contrast to an abundance of reviews and practical approaches to POC coagulation management in trauma patients, there is a scarcity of research in the field and large-scale clinical trials are urgently needed. The paneuropean multicenter trial Implementing Treatment Algorithms for the Correction of Trauma Induced Coagulopathy (iTACTIC) will inform on the potential of viscoelastic tests to augment transfusion protocols for better patient outcomes.

Benefits and Pitfalls of Point-of-Care Coagulation Testing for Anticoagulation Management

Point-of-care (POC) testing is generally less precise and has higher reagent costs per test than laboratory-based assays. However, POC hemostasis testing can offer significant advantages in particular situations: patient-managed warfarin therapy as well as rapid turnaround time heparin management for intraoperative patients. Of note, POC hemostasis testing is generally approved for the purposes of anticoagulation monitoring and is inferior to laboratory coagulation testing for the diagnosis of congenital or acquired coagulopathy. The frequently used POC coagulation instruments for POC international normalized ratio and activated clotting time are reviewed, as well as their typical performance relative to central laboratory testing (where available). Several cases are discussed that highlight the benefits, as well as pitfalls, of POC coagulation testing. POC coagulation testing for anticoagulation monitoring offers advantages in particular situations. Clear policies and protocols must be developed to guide proper use of POC versus central laboratory hemostasis testing.

AB222. 243. Significant coagulopathy post symptomatic abdominal aortic aneurysm—a role for point of care coagulation testing?

AB222. 243. Significant coagulopathy post symptomatic abdominal aortic aneurysm—a role for point of care coagulation testing?

Point of care coagulation testing – review of instruments and results

Overview: Due to the limitations of some POC instruments, including the lack of a liquid internal quality control (QC) material to control and verify the operator's performance, participation in an external quality assurance (EQA) program is of particular importance. Often, the patient testing performed on these POC devices is performed by non-laboratory-trained staff, with limited knowledge of the importance of internal QC and EQA for maintaining quality of testing.

Targeted Bleeding Management Reduces the Requirements for Blood Component Therapy in Lung Transplant Recipients

Objective Lung transplantation is associated with high rates of bleeding and frequent blood transfusion. The authors aimed to determine if point-of-care coagulation testing (POCCT) reduced transfusion requirements. Design, Settings, and Participants A before-and-after cohort analysis conducted at a single tertiary referral center. Ninety-three sequential adult patients between January 2010 and January 2014 undergoing isolated lung transplant without preoperative extracorporeal support were analyzed. Intervention ROTEM and multi-plate POCCT were introduced on July 1, 2012, with an associated algorithm based on the results. Measurements and Main Results Statistically significant decreases in the proportion of patients receiving PRBCs (87% v 65%; p = 0.015), FFP (72% v 30%; p v 37%; p = 0.002) were found after the intervention. There were small decreases in median chest tube blood loss at 2 hours (300 mLs v 215 mLs; p = 0.03) and 4 hours (440 mLs v 350 mLs; p = 0.050) but not at 12 hours postoperatively. There were no changes in reoperation for bleeding (9% v 4%; p = 0.158) or in-hospital mortality (6% v 2%; p = 0.617). The cost of blood products administered decreased from a median of $3,935.00 to $991.00 (p Conclusions Use of POCCT in lung-transplant surgery is associated with significant reductions in blood product use and cost. There were no detectable changes in outcome aside from a small decrease in early postoperative bleeding.

Point-of-Care Coagulation Testing in Cardiac Surgery.

Bleeding complications after cardiac surgery are common and are associated with increased morbidity and mortality. Their etiology is multifactorial, and treatment decisions are time sensitive. Point-of-care (POC) testing has an advantage over standard laboratory tests for faster turn-around times, and timely decision on coagulation intervention(s). The most common POC coagulation testing is the activated clotting time (ACT), used to monitor heparin therapy while on cardiopulmonary bypass. Viscoelastic coagulation tests including thromboelastometry (ROTEM) and thromboelastography (TEG) have been recommended for the treatment of postoperative bleeding after cardiac surgery because the ROTEM/TEG-guided treatment algorithms reduced the use of blood products. Other POC tests are commercially available, but there is sparse evidence for their routine use in cardiac surgery. These devices include heparin management systems, POC prothrombin time and activated partial thromboplastin time, POC fibrinogen assay, and whole blood platelet function tests. There are multiple confounding elements and conditions associated with cardiac surgery, which can significantly alter test results. Anemia and thrombocytopenia are regularly associated with deviations in many POC devices. In summary, POC coagulation testing allows for rapid clinical decisions in hematological interventions, and, when used in conjunction with a proper transfusion algorithm, may reduce blood product usage, and potentially complications associated with blood transfusion.

Targeted Bleeding Management Reduces the Requirements for Blood Component Therapy in Lung Transplant Recipients

Lung transplantation is associated with high rates of bleeding and frequent blood transfusion. The authors aimed to determine if point-of-care coagulation testing (POCCT) reduced transfusion requirements. A before-and-after cohort analysis conducted at a single tertiary referral center. Ninety-three sequential adult patients between January 2010 and January 2014 undergoing isolated lung transplant without preoperative extracorporeal support were analyzed. ROTEM and multi-plate POCCT were introduced on July 1, 2012, with an associated algorithm based on the results. Statistically significant decreases in the proportion of patients receiving PRBCs (87% v 65%; p = 0.015), FFP (72% v 30%; p<0.0001) and platelets (70% v 37%; p = 0.002) were found after the intervention. There were small decreases in median chest tube blood loss at 2 hours (300 mLs v 215 mLs; p = 0.03) and 4 hours (440 mLs v 350 mLs; p = 0.050) but not at 12 hours postoperatively. There were no changes in reoperation for bleeding (9% v 4%; p = 0.158) or in-hospital mortality (6% v 2%; p = 0.617). The cost of blood products administered decreased from a median of $3,935.00 to $991.00 (p<0.001). Use of POCCT in lung-transplant surgery is associated with significant reductions in blood product use and cost. There were no detectable changes in outcome aside from a small decrease in early postoperative bleeding.

Cost-Effectiveness of POC Coagulation Testing Using Multiple Electrode Aggregometry.

The economic effects of Point-of-Care (POC) coagulation testing including Multiple Electrode Aggregometry (MEA) with the Multiplate device have not been examined. A health economic model with associated clinical endpoints was developed to calculate the effectiveness and estimated costs of coagulation analyses based on standard laboratory testing (SLT) or POC testing offering the possibility to assess platelet dysfunction using aggregometric measures. Cost estimates included pre- and perioperative costs of hemotherapy, intra- and post-operative coagulation testing costs, and hospitalization costs, including the costs of transfusion-related complications. Our model calculation using a simulated true-to-life cohort of 10,000 cardiac surgery patients assigned to each testing alternative demonstrated that there were 950 fewer patients in the POC branch who required any transfusion of red blood cells. The subsequent numbers of massive transfusions and patients with transfusion-related complications were reduced with the POC testing by 284 and 126, respectively. The average expected total cost in the POC branch was 288 Euro lower for every treated patient than that in the SLT branch. Incorporating aggregometric analyses using MEA into hemotherapy algorithms improved medical outcomes in cardiac surgery patients in the presented health economic model. There was an overall better economic outcome associated with POC testing compared with SLT testing despite the higher costs of testing.

Protocol guided bleeding management improves cardiac surgery patient outcomes.

Excessive bleeding is a risk associated with cardiac surgery. Treatment invariably requires transfusion of blood products; however, the transfusion itself may contribute to postoperative sequelae. Our objective was to analyse a quality initiative designed to provide an evidenced-based approach to bleeding management. A retrospective analysis compared blood product transfusion and patient outcomes 15 months before and after implementation of a bleeding management protocol. The protocol incorporated point-of-care coagulation testing (POCCT) with ROTEM and Multiplate to diagnose the cause of bleeding and monitor treatment. Use of the protocol led to decreases in the incidence of transfusion of PRBCs (47·3% vs. 32·4%; P < 0·0001), FFP (26·9% vs. 7·3%; P < 0·0001) and platelets (36·1% vs. 13·5%; P < 0·0001). During the intra-operative period, the percentage of patients receiving cryoprecipitate increased (2·7% vs. 5·1%; P = 0·002), as did the number of units transfused (248 vs. 692; P < 0·0001). The proportion of patients who received tranexamic acid increased (13·7% to 68·2%; P < 0·0001). There were reductions in re-exploration for bleeding (5·6% vs. 3·4; P = 0·01), superficial chest wound (3·3% vs. 1·4%; P = 0·002), leg wound infection (4·6% vs. 2·0%; P < 0·0001) and a 12% reduction in mean length of stay from operation to discharge (95%: 9-16%, P < 0·0001). Acquisition cost of blood products decreased by $1 029 118 in the 15-month period with the protocol. The implementation of a bleeding management protocol supported by POCCT in a cardiac surgery programme was associated with significant reductions in the transfusion of allogeneic blood products, improved outcomes and reduced cost.

Transfusion practices in trauma.

Resuscitation of a severely traumatised patient with the administration of crystalloids, or colloids along with blood products is a common transfusion practice in trauma patients. The determination of this review article is to update on current transfusion practices in trauma. A search of PubMed, Google Scholar, and bibliographies of published studies were conducted using a combination of key-words. Recent articles addressing the transfusion practises in trauma from 2000 to 2014 were identified and reviewed. Trauma induced consumption and dilution of clotting factors, acidosis and hypothermia in a severely injured patient commonly causes trauma-induced coagulopathy. Early infusion of blood products and early control of bleeding decreases trauma-induced coagulopathy. Hypothermia and dilutional coagulopathy are associated with infusion of large volumes of crystalloids. Hence, the predominant focus is on damage control resuscitation, which is a combination of permissive hypotension, haemorrhage control and haemostatic resuscitation. Massive transfusion protocols improve survival in severely injured patients. Early recognition that the patient will need massive blood transfusion will limit the use of crystalloids. Initially during resuscitation, fresh frozen plasma, packed red blood cells (PRBCs) and platelets should be transfused in the ratio of 1:1:1 in severely injured patients. Fresh whole blood can be an alternative in patients who need a transfusion of 1:1:1 thawed plasma, PRBCs and platelets. Close monitoring of bleeding and point of care coagulation tests are employed, to allow goal-directed plasma, PRBCs and platelets transfusions, in order to decrease the risk of transfusion-related acute lung injury.

Transfusion practices in trauma

Sir, I read the recently published article by Ramakrishnan and Cattamanchi[1] on “Transfusion practice in trauma” with great interest. The authors have advocated the use of high ratio, that is 1:1:1 of fresh frozen plasma (FFP): Packed red blood cell (RBC): Platelet concentrate in trauma patients with life-threatening injuries. The article is convincing but few points need to be considered in the current practice. Although many published studies have supported high FFP: RBCs ratio, these observations have their own limitations.[2,3] A recent analysis of 26 studies relating to blood ratios in trauma concluded that because of the difficulties presented in trying to exclude survivor bias, the available evidence relating to higher ratios of FFP: RBC are inconclusive, and prospective trials are required.[3] The article has emphasised the importance of early recognition of trauma-induced coagulopathy (TIC) but the standard laboratory tests (prothrombin time, international normalised ratio, and/or activated partial thromboplastin time) used in most trauma centres to assess coagulopathy and guide haemostatic therapy require extended length of time to process the results. Thus, these tests defeat the idea of early recognition of TIC. In addition, these lab tests do not address many important issues such as clot strength and stability and extent of any existing hyperfibrinolysis etc. Authors have mentioned point of care coagulation testing as a future substitute to formula-driven methodology. The individualised theragnostic management of TIC holds many advantages over the ratio-driven approach.[4] Goal directed transfusion therapy guided by thromboelastography and rotational thromboelastometry relies on real-time monitoring of coagulation status to guide the targeted supplementation of haemostatic agents; evaluation of subsequent response to blood component therapy rapidly addresses the haemostatic needs of the individual. Thus, we can prevent inappropriate treatment of post-injury coagulopathy where less transfusion may not effectively treat TIC and little more transfusion may increase the risk of acute respiratory distress syndrome, multiple organ failure and acute lung injury. Hence, in the present scenario where more prospective randomised controlled trials are required to establish the optimum ratios of blood products and where there is no consensus among physicians regarding goal directed therapy, we are still in dilemma. Further studies may enforce the later strategy in practice of blood transfusion in trauma and may protect patients from avoidable complications of unnecessary transfusion of blood products.

Transfusion practices in trauma.

Resuscitation of a severely traumatised patient with the administration of crystalloids, or colloids along with blood products is a common transfusion practice in trauma patients. The determination of this review article is to update on current transfusion practices in trauma. A search of PubMed, Google Scholar, and bibliographies of published studies were conducted using a combination of key-words. Recent articles addressing the transfusion practises in trauma from 2000 to 2014 were identified and reviewed. Trauma induced consumption and dilution of clotting factors, acidosis and hypothermia in a severely injured patient commonly causes trauma-induced coagulopathy. Early infusion of blood products and early control of bleeding decreases trauma-induced coagulopathy. Hypothermia and dilutional coagulopathy are associated with infusion of large volumes of crystalloids. Hence, the predominant focus is on damage control resuscitation, which is a combination of permissive hypotension, haemorrhage control and haemostatic resuscitation. Massive transfusion protocols improve survival in severely injured patients. Early recognition that the patient will need massive blood transfusion will limit the use of crystalloids. Initially during resuscitation, fresh frozen plasma, packed red blood cells (PRBCs) and platelets should be transfused in the ratio of 1:1:1 in severely injured patients. Fresh whole blood can be an alternative in patients who need a transfusion of 1:1:1 thawed plasma, PRBCs and platelets. Close monitoring of bleeding and point of care coagulation tests are employed, to allow goal-directed plasma, PRBCs and platelets transfusions, in order to decrease the risk of transfusion-related acute lung injury.

Point-of-care coagulation testing

Point-of-care testing (POCT) may be defined as the rapid specific testing of bodily fluids at the bedside. There is an ever-increasing array of POCT available, most of which are beyond the remit of this article which will concentrate upon those commonly used and relevant to the management of perioperative coagulation. Owing to the relatively long turnaround time of conventional laboratory tests, and with the aim of reducing inappropriate transfusion, there is increasing interest in point-of-care coagulation testing (POCCT) which can provide results within minutes. In addition, the wide acceptance of the current cell-based model of coagulation has led to an emphasis on the pivotal role of platelets and particular interest in devices testing whole blood, rather than plasma used in laboratory-based tests. The latter include the prothrombin time (PT) and activated partial thromboplastin time (aPTT) which provide information on the first phase of coagulation up to fibrin formation. Conversely, viscoelastic POCCT devices produce information on all phases of coagulation, providing insight into interactions between the cellular and plasma components of whole blood and the activity of the fibrinolytic system; all of which are vital for successful haemostasis. The advantages and disadvantages of POCT are listed in Table 1.

Perioperative Point of Care Coagulation Testing

Conventional laboratory tests of blood coagulation yield only partial diagnostic information. "Point of care" (POC) devices are increasingly being used at the bedside perioperatively for rapid, detailed testing of hemostatic function and for treatment monitoring in patients with coagulopathies. In this review, we discuss the benefits and limitations of POC coagulation testing-in particular, its effects on the rate of perioperative transfusion of allogeneic blood products, on the frequency of other types of hemostatic treatment, and on the clinical outcome. This article is based on a selective review of pertinent literature retrieved by a search in PubMed. The clinical value of preoperative POC screening for coagulopathies has not yet been examined in a prospective, randomized clinical trial. On the other hand, studies in patients with coagulopathies undergoing (mainly cardiac) surgery have shown that algorithm-based hemostatic treatment based on viscoelastic POC coagulation testing reduces both perioperative blood loss and the rate of transfusion of allogeneic blood products. None of the studies published to date had adequate power to reveal any independent effect of POC coagulation testing on perioperative morbidity or mortality. Despite certain limitations that must be borne in mind, POC techniques are a valuable means of testing various aspects of hemostasis rapidly and in detail. Their implementation in hemostatic treatment algorithms may reduce both the rate of transfusion of allogeneic blood products and the total cost of treatment for blood loss and coagulopathies. The putative effect of POC testing on perioperative morbidity and mortality has not yet been demonstrated.

Intrarater and interrater variability of point of care coagulation testing using the ROTEM delta

This study aimed to assess intrarater and interrater variability of coagulation point-of-care testing (POCT) using ROTEM delta operated by trained staff. Arterial blood samples were taken from 43 anesthetized piglets aged up to 6 weeks and weighing 4-6 kg. The following clotting measurements were recorded: clotting time, clot formation time (CFT), maximum clot firmness (MCF) and alpha angle using ROTEM delta assays ExTEM, InTEM, FibTEM and ApTEM. Intrarater variability was assessed when a single operator performed the same assay simultaneously in all four channels of the ROTEM device. Interrater variability was assessed by two different operators simultaneously performing the same assay. Variance components of the data were analyzed using linear mixed modeling. Three hundred and forty-three tests from 86 samples were loaded and analyzed. The intraclass correlation coefficient (ICC) was more than 0.7 for clotting measurements except for CFT and alpha in InTEM. For intrarater and interrater assessment, different relative variability for the ROTEM measurements were found with consistently higher variability for clotting time and CFT and lower variability of MCF and alpha angle. Interrater variability was not statistically significant as supported using Akaike's information criterion. Piglet coagulation testing using ROTEM delta showed a high ICC. Variability was significantly lower in MCF and angle alpha compared with clotting time and CFT. No further variability was added by a second user. Based on these data, ROTEM delta appears to be suitable as POCT.

Living without aprotinin: the results of a 5‐year blood saving program in cardiac surgery

After 20 years of regular use in cardiac surgery patients, aprotinin has recently been withdrawn from the market due to many concerns about its safety. For a number of reasons aprotinin has not been available in Italy since 1998. The present study presents an aprotinin-free treatment protocol applied at our institution during the last 5 years, and aims to verify the results of this protocol in terms of allogeneic blood product transfusions, postoperative blood loss and surgical re-exploration rate. Retrospective study on 7988 consecutive patients who underwent cardiac surgery during the years 2003-2007. All the patients received specific hemostasis/coagulation management based on (a) routine use of tranexamic acid, (b) heparin dose-response monitoring, thromboelastography, platelet (PLT) function analysis in a select population of patients, and (c) use of fresh frozen plasma (FFP), PLTs, and desmopressin according to the hemostasis/coagulation profile. Data retrieved from the institutional database were quantity of packed red cells (PRCs), FFP, PLT transfusion rate, blood loss in the first 12 postoperative hours, and surgical re-exploration rate. PRCs were transfused in 40.4% of patients (with higher rates for selected high-risk subpopulations), FFP in 12.9% and PLTs in 2.6%. Surgical re-exploration rate was 3.7%. With respect to historical controls, a significant reduction of PRCs and FFP transfusions was obtained using closed circuits, point of care coagulation tests, and combination of the two. This aprotinin-free blood saving program is an effective strategy for allogeneic blood products transfusion containment.