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Background Post-partum haemorrhage (PPH) causes rapidly developing deficiencies in clotting factors and contributes to substantial maternal morbidity and mortality. Rotational thromboelastometry (ROTEM®) is increasingly used as a point of care coagulation monitoring device in patients with massive haemorrhage; however, there are limited data on reference ranges in the peri-partum period. These are required due to the haemostatic changes in pregnancy. Methods In a Dutch multi-centre trial, 161 subjects were included; blood samples were obtained during labour (T1) and within 1 h of delivery (T2). Reference ranges of ROTEM® INTEM, EXTEM, FIBTEM, and APTEM were set and correlation with laboratory results was investigated using the guidelines of the International Federation of Clinical Chemistry. Results Reference ranges were obtained for clotting time (CT), clot formation time (CFT), α-angle, clot firmness at 10 and 20 min (A10, A20), maximum clot firmness (MCF), and maximum lysis (ML). These were comparable from centre to centre, and between T1 and T2. Reference ranges T1: EXTEM: CT 31–63 s, CFT 41–120 s, and MCF 42–78 mm. INTEM: CT 109–225 s, CFT 40–103, and MCF 63–78 mm. FIBTEM: CT 31–79 s and MCF 13–45 mm. APTEM: CT 33–62 s, CFT 42–118, and MCF 61–79 mm. Conclusions Reference values for ROTEM® parameters are reported. The previously published correlation between FIBTEM parameters and plasma fibrinogen levels by the Clauss method is confirmed. Further research is needed to define threshold values for haemostatic therapy in the course of PPH. Clinical trial registration NTR 2515 (http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2515). [ABSTRACT FROM PUBLISHER]

Background Convulsive seizures (CS) occur in ∼1% of the patients after cardiac surgery with cardiopulmonary bypass. Recent investigations indicate an up to seven-fold increase in CS in cardiac surgical patients receiving high doses (≥60 mg kg−1 body weight) of tranexamic acid (TA). Methods In a retrospective data analysis of 4883 cardiac surgical patients, we investigated the incidence of CS in patients receiving a moderate dose of TA (24 mg kg−1 body weight) compared with a reference group not receiving TA as a primary endpoint. Secondary endpoints were intensive care unit stay and in-hospital mortality. We performed propensity score (PS)-adjusted logistic regression analysis to test the association between TA use/non-use and clinical outcomes. Results Compared with the reference group, the PS-adjusted odds ratio (OR) for CS in the TA group was 1.703 [95% confidence interval (CI): 1.01–2.87; P=0.045; incidence 2.5% vs 1.2%]. Log-ICU-stay was significantly longer (P=0.004) and PS-adjusted relative in-hospital mortality risk was significantly higher for the TA group compared with the reference group (OR=1.89; 95% CI: 1.21–2.96; P=0.005). Both the TA-associated CS incidence and the in-hospital mortality risk were only significant in patients undergoing open-heart surgery (OR=2.034, 95% CI: 1.07–3.87; P=0.034 and OR=2.20, 95% CI: 1.32–3.69; P=0.003, respectively) but not in patients undergoing coronary artery bypass grafting (OR=1.21, 95% CI: 0.49–3.03; P=0.678 and OR=1.13, 95% CI: 0.42–3.02; P=0.809, respectively). Conclusions In open-heart surgery, even moderate TA doses are associated with a doubled rate of CS and in-hospital mortality. Prospective trials are needed to further evaluate the safety profile of TA in cardiac surgery. [ABSTRACT FROM AUTHOR]

Background Fresh-frozen plasma (FFP) is widely used in critically ill patients, despite a weak evidence base. Factors that influence the decision to transfuse FFP before intravascular catheter insertion are poorly described. Methods We undertook a case-controlled study based on a prospective cohort study of 1923 admissions to 29 intensive care units in the UK. Non-bleeding patients with an international normalized ratio (INR) ≥1.5 who underwent intravascular catheterization, but no other invasive procedure, were identified. We compared patient characteristics, illness-related factors, and biochemical and haematological variables between patients who did or did not receive pre-procedural FFP. Results One hundred and eighty-six patients fulfilled the criteria; 26 received FFP during the 24 h before line insertion (cases) and 160 did not (controls). Factors associated with greater use of prophylactic FFP by clinicians were pre-existing chronic liver disease (P=0.01), higher serum bilirubin before procedure (P=0.01), lower platelet count (P=0.01), higher activated partial thromboplastin time (P=0.001), lower fibrinogen (P=0.01), and concurrent red cell transfusion despite the absence of bleeding (P=0.001). There was no difference in pre-procedural INR [median (1st, 3rd quartile) cases: 1.95 (1.85, 2.6); controls 1.8 (1.6, 2.3); P=0.19]. The mean FFP dose was 11.1 ml kg−1 (sd 5.7 ml kg−1); 53.8% of cases were transfused <10 ml kg−1. Conclusions Chronic liver disease and more abnormal coagulation tests were associated with greater probability of pre-procedural FFP administration before vascular catheterization, whereas the severity of prothrombin time prolongation alone was not. FFP was more likely to be administered when red cells were also transfused, even in the absence of bleeding. [ABSTRACT FROM PUBLISHER]

Background Hydroxyethyl starch (HES) solutions alter blood coagulation, mainly platelet function and fibrinogen polymerization. Haemostasis can also be impaired by dilutional-hyperchloraemic acidosis induced by the HES carrier solution. We hypothesized that a saline-based tetrastarch carrier solution impairs parameters of blood coagulation more than a balanced carrier solution. Methods The study was designed as a prospective, double-blinded, randomized, cross-over trial in healthy male volunteers. At intervals of at least 10 days, 13 subjects received 20 ml kg−1 of balanced or saline-based tetrastarch over 2 h. Blood was subjected to blood gas analysis, assessment of platelet function [with multiple electrode aggregometry (MEA)], and clot formation (with rotational thrombelastometry). Results Maximum aggregation in response to adenosine diphosphate (ADP) decreased after saline-based HES infusion, but not after balanced solution-based HES infusion. ADP-induced platelet aggregation was significantly lower after saline-based HES compared with baseline (21%; P<0.025) and compared with balanced solution-based HES (17%; P<0.025). There were no significant changes in platelet aggregation induced by thrombin receptor-activating peptide and in any parameter of rotational thrombelastometry. Chloride concentrations were significantly higher after saline-based HES compared with balanced solution-based HES. Conclusions The carrier solution for HES up to 20 ml kg−1 had little impact on platelet aggregation or clot formation as assessed by MEA and rotational thrombelastometry, respectively. Further clinical studies are required to verify this finding in patients and to correlate results of whole blood aggregometry and rotational thrombelastometry with perioperative bleeding and transfusion requirements. [ABSTRACT FROM PUBLISHER]

Background Surgical excision of burn wounds is often associated with severe bleeding. Timely and targeted correction of coagulopathy reduces transfusion requirements and improves survival in trauma victims. We hypothesized that rapid correction of coagulopathy after a treatment algorithm based on point-of-care viscoelastic coagulation testing would decrease allogeneic blood product transfusions during surgical excision of burn wounds. Methods Thirty consecutive patients undergoing surgical excision of burn wounds were enrolled into this prospective, randomized, controlled, single-centre study. In the control group, coagulation management was performed according to the clinicians' discretion. For the algorithm group, we standardized treatment based on the Austrian recommendation for the management of trauma-induced coagulopathy using point-of-care rotational thromboelastometry (ROTEM®). The main outcome parameter was the cumulative number of allogeneic blood units transfused on the day of surgery. Results The difference between the groups regarding the cumulative use of allogeneic blood products was highly significant with 3.0 (1.3–5.5) blood products in the algorithm group compared with 9.0 (6.0–12.3) in the control group [median (inter-quartile range); P=0.002]. No plasma was administered in the algorithm group compared with 5.0 (1.5–7.5) units overall in the control group (P<0.001). Fibrinogen concentrate administration was not significantly different between the groups (P=0.89). Tranexamic acid was not administered. Conclusions The significant reduction in allogeneic blood product requirements during surgical burn wound excision is a prospective proof of concept that a bleeding management algorithm based on thromboelastometry is efficacious. Hypofibrinogenaemia and hyperfibrinolysis are not significant pathomechanisms of bleeding in this setting and ROTEM® helps to avoid unnecessary interventions. [ABSTRACT FROM AUTHOR]

Background Thromboelastometry (ROTEM®) might be useful to detect intraoperative coagulation disorders early in major paediatric surgery. This observational trial compares this technique to standard coagulation tests. Methods Intraoperative blood sampling was obtained in children undergoing elective major surgery. At each time point, standard coagulation tests [activated partial thromboplastin time (aPTT), prothrombin time (PT), and fibrinogen level] and ROTEM® analyses (InTEM, ExTEM, and FibTEM) were performed simultaneously by trained hospital laboratory staff. Results A total of 288 blood samples from 50 subjects were analysed. While there was a poor correlation between PT and aPTT to ExTEM clotting time (CT) and InTEM CT, respectively, a good correlation was detected between PT and aPTT to clot formation time, and a very good correlation between fibrinogen level and FibTEM assay (r=0.882, P<0.001). Notably, 64% of PT and 94% of aPTT measurements were outside the reference range, while impaired CT was observed in 13% and 6.3%, respectively. Standard coagulation test results were available after a median of 53 min [inter-quartile range (IQR): 45–63 min], whereas 10 min values of ROTEM® results were available online after 23 min (IQR: 21–24 min). Conclusions PT and aPTT cannot be interchangeably used with ROTEM® CT. Based on the results of ROTEM®, recommended thresholds for PT and aPTT might overestimate the need for coagulation therapy. A good correlation was found between the fibrinogen level and the FibTEM assay. In addition, ROTEM® offered faster turnaround times. [ABSTRACT FROM PUBLISHER]

Background ROTEM®/TEG® (rotational thromboelastometry) assays appear to be useful for the treatment of bleeding trauma patients. However, data on the prevalence and impact of abnormal ROTEM® assays are scarce. Methods This is a prospective cohort study of blunt trauma patients (Injury Severity Score ≥15 or Glasgow Coma Score ≤14) admitted to Innsbruck Medical University Hospital between July 2005 and July 2008. Standard coagulation tests, antithrombin (AT), prothrombin fragments (F1+2), thrombin–antithrombin complex (TAT), and ROTEM® assays were measured after admission. Data on 334 patients remained for final analysis. Results ROTEM® parameters correlated with standard coagulation tests (all Spearman r>0.5), and significant differences in mortality were detected for defined ROTEM® thresholds [FIBTEM 7 mm (21% vs 9%, P=0.006), EXTEM MCF (maximum clot firmness) 45 mm (25.4% vs 9.4%, P=0.001)]. EXTEM MCF was independently associated with early mortality [odds ratio (OR) 0.94, 95% confidence interval (CI) 0.9–0.99] and MCF FIBTEM with need for red blood cell transfusion (OR 0.92, 95% CI 0.87–0.98). In polytrauma patients with or without head injury (n=274), the prevalence of low fibrinogen concentrations, impaired fibrin polymerization, and reduced clot firmness was 26%, 30%, and 22%, respectively, and thus higher than the prolonged international normalized ratio (14%). Hyperfibrinolysis increased fatality rates and occurred as frequently in isolated brain injury (n=60) as in polytrauma (n=274) (5%, 95% CI 1.04–13.92 vs 7.3%, 95% CI 4.52–11.05). All patients showed elevated F1+2 and TAT and low AT levels, indicating increased thrombin formation. Conclusions Our data enlarge the body of evidence showing that ROTEM® assays are useful in trauma patients. Treatment concepts should focus on maintaining fibrin polymerization and treating hyperfibrinolysis. [ABSTRACT FROM AUTHOR]

Background The small sample volume needed and the prompt availability of results make viscoelastic methods like rotational thromboelastometry (ROTEM®) attractive for monitoring coagulation in small children. However, data on reference ranges for ROTEM® parameters in children are scarce. Methods Four hundred and seven children (ASA I and II) undergoing elective surgery were recruited for this prospective, two-centre, observational study. Subjects were grouped as follows: 0–3, 4–12, 13–24 months, 2–5, 6–10, and 11–16 yr. Study objectives were to establish age-dependent reference ranges for ROTEM® assays, analyse age dependence of parameters, and compare ROTEM® data with standard coagulation tests. Results Data from 359 subjects remained for final analysis. Except for extrinsically activated clot strength and lysis, parameters for ROTEM® assays were significantly different among all age groups. The most striking finding was that subjects aged 0–3 months exhibited accelerated initiation (ExTEM coagulation time: median 48 s, Q1–Q3 38–65 s; P=0.001) and propagation of coagulation (α angle: median 78o, Q1–Q3 69–84o; P<0.001) and maximum clot firmness (median 62 mm, Q1–Q3 54–74 mm), although standard plasma coagulation test results were prolonged (prothrombin time: median 13.2 s, Q1–Q3 12.6–13.6 s; activated partial thromboplastin time: median 42 s, Q1–Q3 40–46 s). Lysis indices of <85% were observed in nearly one-third of all children without increased bleeding tendency. Platelet count and fibrinogen levels correlated significantly with clot strength, and fibrinogen levels correlated with fibrin polymerization. Conclusions Reference ranges for ROTEM® assays were determined for all paediatric age groups. These values will be helpful when monitoring paediatric patients and in studies of perioperative coagulation in children. [ABSTRACT FROM AUTHOR]

Background: Colloids are often used after cardiac surgery as intravascular volume replacement therapy. Cardiac surgical patients have an increased risk of bleeding. Both hydroxyethylstarch (HES) and gelatin solutions impair haemostasis. We examined the impact and dose effect on coagulation of HES 130/0.4, gelatin, or Ringer's acetate solutions after cardiac surgery. [ABSTRACT FROM PUBLISHER]

Background: Normalization of plasma fibrinogen levels may be associated with satisfactory haemostasis and reduced bleeding. The aim of this retrospective study was to assess fibrinogen recovery parameters after administration of fibrinogen concentrate (Haemocomplettan® P) to patients with diffuse bleeding in cardiovascular surgery. Data on transfusion and patient outcomes were also collected. [ABSTRACT FROM PUBLISHER]

Background: Orthotopic liver transplantation can be associated with haemorrhage, particularly in patients with severe liver dysfunction. We assessed the value of rotation thromboelastometry (ROTEM®) to monitor coagulation in the operating theatre, its correlation with routine laboratory findings, and its ability to guide platelet (Plt) and fibrinogen (Fg) transfusion. [ABSTRACT FROM PUBLISHER]

Background: Patients with a recently implanted coronary drug-eluting stent (DES) who need urgent surgery are at increased risk of surgical bleeding unless clopidogrel is discontinued beforehand, but clopidogrel discontinuation has been associated with a high rate of adverse events due to stent thrombosis. This pilot study tested the hypothesis that the i.v. perioperative administration of the short-acting antiplatelet agent tirofiban allows the safe withdrawal of clopidogrel without increasing the rate of surgical bleeding. [ABSTRACT FROM PUBLISHER]

Human albumin (HA) is widely used for volume replacement or correction of hypoalbuminaemia. The value of HA in the clinical setting continues to be controversial, and it is unclear whether in today's climate of cost consciousness, there is still a place for such a highly priced substance. It is therefore appropriate to update our knowledge of the value of HA. With the exception of women in early pregnancy, there appears to be few indications for the use of HA to correct hypovolaemia. Some studies of traumatic brain injury and intensive care patients suggest negative effects on outcome and organ function of (hyperoncotic) HA. Modern synthetic colloids appear to be a cheaper alternative for maintaining colloid oncotic pressure. The value of using HA to correct hypoalbuminaemia has not been clearly justified. Theoretical and pharmacological benefits of HA, such as oxygen radical scavenging or binding of toxic substances, have not as yet been shown to have beneficial clinical consequences. Experimental data from cell lines or animals do not appear to mimic the clinical setting. Convincing data justifying the use of HA either for treating hypovolaemia or for correcting hypoalbuminaemia are still lacking. A restricted use of HA is recommended. [ABSTRACT FROM PUBLISHER]

Background: We considered whether haemorrhage after a liver trauma would be reduced by early administration of a pro-haemostatic agent and evaluated the effect of i.v. vs i.m. administration of the coagulation factor VIIa analogue NN1731 on haemorrhage after a liver trauma in the pig. [ABSTRACT FROM PUBLISHER]

Background: The study was conducted to explore the effects of colloid and crystalloid solutions on activation of fibrinolysis during orthopaedic surgery and to determine whether fluids facilitate clot dissolution at a particular fibrinolytic activity. [ABSTRACT FROM PUBLISHER]

Purpose: To evaluate the efficacy and safety of subselective arterial embolization with polyvinyl alcohol (PVA) particles with or without microcoil augmentation to control postoperative lower gastrointestinal (GI) bleeding.Methods: Ten patients with clinical, scintigraphic, and angiographic evidence of postoperative lower GI bleeding were considered for subselective embolization. Subselective embolizations were performed through coaxial microcatheters with 355-500 micron PVA particles with or without additional coil embolization.Results: Embolization was technically successful in 9 of 10 (90%) patients. In one patient, subselective embolization was not possible; consequently no embolization was performed. Clinical success was achieved after a single embolization in 6 of 10 (60%) patients and after a second embolization in an additional 3 of the 10 (30%) patients. While there was no rebleeding in patients with normal coagulation parameters, all three patients (100%) with coagulopathy rebled, two of them from another source. Although no acute ischemic effects developed, no long-term sequela such as ischemic stricture were specifically looked for. Seven patients developed abdominal discomfort and/or fever within 24-48 hr. Four of 10 patients died of complications other than hemorrhage or ischemia.Conclusion: Subselective PVA embolization with or without a microcoil embolization is an effective and safe means of managing postoperative lower GI hemorrhage in patients with multiorgan trauma. [ABSTRACT FROM AUTHOR]

Inherited factor VII (FVII) deficiency is a rare autosomal-recessive bleeding disorder. There are no clear guidelines regarding therapy in such patients when intracerebral surgery is performed. We report the use of recombinant activated FVII (rFVIIa) for the prophylaxis of bleeding in a female with FVII deficiency (8% of activity) undergoing urgent removal of a right fronto-rolandic intracerebral haematoma secondary to a bleeding from a cavernous angioma. To assist haemostasis during and after surgery, rFVIIa boluses were administered during the procedure and continued every 12 h during 3 days after operation to maintain a prothrombin time <15 s. Using this approach, no abnormal bleeding or thromboembolic complications were observed and rFVIIa appeared safe in this context. [ABSTRACT FROM PUBLISHER]

Background: Single-dose human fibrinogen concentrate (FCH) might have haemostatic benefits in complex cardiovascular surgery., Methods: Patients undergoing elective aortic surgery requiring cardiopulmonary bypass were randomly assigned to receive FCH or placebo. Study medication was administered to patients with a 5 min bleeding mass of 60-250 g after separation from bypass and surgical haemostasis. A standardized algorithm for allogeneic blood product transfusion was followed if bleeding continued after study medication., Results: 519 patients from 34 centres were randomized, of whom 152 (29%) met inclusion criteria for study medication. Median (IQR) pretreatment 5 min bleeding mass was 107 (76-138) and 91 (71-112) g in the FCH and placebo groups, respectively (P=0.13). More allogeneic blood product units were administered during the first 24 h after FCH, 5.0 (2.0-11.0), when compared with placebo, 3.0 (0.0-7.0), P=0.026. Fewer patients avoided transfusion in the FCH group (15.4%) compared with placebo (28.4%), P=0.047. The FCH immediately increased plasma fibrinogen concentration and fibrin-based clot strength. Adverse event rates were comparable in each group., Conclusions: Human fibrinogen concentrate was associated with increased allogeneic blood product transfusion, an unexpected finding contrary to previous studies. Human fibrinogen concentrate may not be effective in this setting when administered according to 5-minute bleeding mass. Low bleeding rates and normal-range plasma fibrinogen concentrations before study medication, and variability in adherence to the complex transfusion algorithm, may have contributed to these results., Clinical Trial Registration: ClinicalTrials.gov identifier no. NCT01475669; EudraCT trial no. 2011-002685-20., (© The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Hypofibrinogenaemia is one of the main reasons for development of perioperative coagulopathy during major paediatric surgery. The aim of this study was to assess whether prophylactic maintenance of higher fibrinogen concentrations through administration of fibrinogen concentrate would decrease the volume of transfused red blood cell (RBCs)., Methods: In this prospective, randomised, clinical trial, patients aged 6 months to 17 yr undergoing craniosynostosis and scoliosis surgery received fibrinogen concentrate (30 mg kg(-1)) at two predefined intraoperative fibrinogen concentrations [ROTEM(®) FIBTEM maximum clot firmness (MCF) of <8 mm (conventional) or <13 mm (early substitution)]. Total volume of transfused RBCs was recorded over 24 h after start of surgery., Results: Thirty children who underwent craniosynostosis surgery and 19 children who underwent scoliosis surgery were treated per protocol. During craniosynostosis surgery, children in the early substitution group received significantly less RBCs (median, 28 ml kg(-1); IQR, 21 to 50 ml kg(-1)) compared with the conventional fibrinogen trigger of <8 mm (median, 56 ml kg(-1); IQR, 28 to 62 ml kg(-1)) (P=0.03). Calculated blood loss as per cent of estimated total blood volume decreased from a median of 160% (IQR, 110-190%) to a median of 90% (IQR, 78-110%) (P=0.017). No significant changes were observed in the scoliosis surgery population. No bleeding events requiring surgical intervention, postoperative transfusions of RBCs, or treatment-related adverse events were observed., Conclusions: Intraoperative administration of fibrinogen concentrate using a FIBTEM MCF trigger level of <13 mm can be successfully used to significantly decrease bleeding, and transfusion requirements in the setting of craniosynostosis surgery, but not scoliosis., Clinical Trial Registry Number: ClinicalTrials.gov NCT01487837., (© The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Patients with cardiovascular disease have an array of haemostasis disorders that predispose to the development of thrombotic and embolic disease states. These patients are often maintained on anti-thrombotic medication to prevent adverse cardiovascular events. Patients undergoing cardiac surgery also have haemostatic disorders that include their intrinsic disease state, adjunctive medication, and the coagulation disturbances induced by cardiopulmonary bypass. The following review introduces the monitors that are available for monitoring perioperative coagulation, with an emphasis on cardiovascular surgery. Heparin monitors, platelet function monitors for use in transfusion algorithms, and monitoring anti-platelet drugs will be discussed. [ABSTRACT FROM PUBLISHER]