Fluid resuscitation following traumatic injury causes haemodilution and can contribute to coagulopathy. Coagulation factor replacement may be necessary to prevent bleeding complications of dilutional coagulopathy. Compared with fresh frozen plasma (FFP), prothrombin complex concentrate (PCC) may potentially offer a more rapid and effective means of normalizing coagulation factor levels.
In anaesthetized mildly hypothermic pigs, 65–70% of total blood volume was substituted in phases with hydroxyethyl starch and red cells. Animals were then treated with 15 ml kg−1 isotonic saline placebo, 25 IU kg−1 PCC, or 15 ml kg−1 FFP. Immediately thereafter, either a standardized femur or spleen injury was inflicted, and coagulation function, including thrombin generation, and bleeding were assessed. An additional group received high-dose FFP (40 ml kg−1) before femur injury.
Haemodilution markedly prolonged prothrombin time and reduced peak thrombin generation. PCC, but not FFP, fully reversed those effects. Compared with 15 ml kg−1 FFP, PCC shortened the time to haemostasis after either bone (P=0.001) or spleen (P=0.028) trauma and reduced the volume of blood lost (P<0.001 and P=0.015, respectively). Subsequent to bone injury, PCC also accelerated haemostasis (P=0.003) and diminished blood loss (P=0.006) vs 40 ml kg−1 FFP.
PCC was effective in correcting dilutional coagulopathy and controlling bleeding in an in vivo large-animal trauma model. In light of its suitability for more rapid administration than FFP, PCC merits further investigation as a therapy for dilutional coagulopathy in trauma and surgery.
blood, haemodilution; complications, haemorrhagic disorder; complications, trauma; fresh frozen plasma; prothrombin complex concentrate
Prothrombin complex concentrate (PCC) is a term to describe pharmacological products that contain lyophilized, human plasma-derived vitamin K-dependent factors (F), FII, FVII, FIX, FX, and various amounts of proteins C and S. PCCs can be rapidly reconstituted in a small volume (20 ml for about 500 international units (IU)) at bedside and administered regardless of the patient’s blood type. PCCs are categorized as 4-factor PCC if they contain therapeutic amounts of FVII, and 3-factor PCC when FVII content is low. In addition, activated PCC which contains activated FVII and FX with prothrombin is available for factor VIII bypassing therapy in hemophilia patients with inhibitors. Currently, 4-factor PCC is approved for the management of bleeding in patients taking warfarin, but there has been increasing use of various PCCs in the treatment of acquired perioperative coagulopathy unrelated to warfarin therapy and in the management of bleeding due to novel oral anticoagulants. There is also an ongoing controversy about plasma transfusion and its potential hazards including transfusion-related lung injury (TRALI). Early fixed ratio plasma transfusion has been implemented in many trauma centers in the USA, whereas fibrinogen concentrate and PCC are preferred over plasma transfusion in some European centers.
In this review, the rationales for including PCCs in the perioperative hemostatic management will be discussed in conjunction with plasma transfusion.
Coagulation; Fresh frozen plasma; Prothrombin complex concentrate; Recombinant activated factor VII; Factor eight bypassing agent; Thromboelastometry
Prothrombin complex concentrates (PCCs) are sometimes used as ‘off label’ for excessive bleeding after cardiopulmonary bypass (CPB). The main objective of this study was to retrospectively evaluate the clinical and biological efficacy of PCC in this setting.
We reviewed the charts of all patients who had undergone cardiac surgery under CPB in our institution for 2 years. Patients treated for active bleeding with haemostatic therapy were identified. Chest tube blood loss was quantified postoperatively in the first 24 h. Coagulation parameters were recorded at intensive care unit admission and in the patient's first 24 h. Thromboembolic complications were also ascertained.
Seventy-seven patients out of the 677 studied (11.4%) were included: PCC was solely administered in 24 patients (group I), fresh frozen plasma in 26 (group II) and both in 27 (group III). The mean dose of PCC was 10.0 UI/kg ± 3.5 for group I vs 14.1 UI/kg ± 11.2 for group III (P = 0.09). Initial blood loss in the first hour was different between the three groups (P = 0.05): 224 ± 131 ml for group I, 369 ± 296 ml for group II and 434 ± 398 ml for group III. Only group I vs group III presented a significant difference (P = 0.02). Variations of blood loss over time were no different according to the treatment groups (P = 0.12). Reductions in blood loss expressed in percentage showed no difference between the three groups after 2 h: 54.5% (68.6–30.8) for group I; 45.0% (81.6–22.2) for group II; 57.6 (76.0–2.1) for group III; (P = 0.89). Re-exploration for bleeding involved 1 patient in group I (4%), 2 in group II (8%) and 10 in group III (37%) (P = 0.002). Except for fibrinogen, variations of prothrombin time, activated partial thromboplastin time and platelets with time were not different according to the treatment groups. Cerebral infarction occurred in one patient in group II.
Administration of low-dose of PCC significantly decreased postoperative bleeding after CPB.
Prothrombin complex concentrates; Bleeding; Cardiopulmonary bypass; Thromboembolic complications
Major blood loss can often be life-threatening and is most commonly encountered in the settings of surgery and trauma. Patients receiving anticoagulant therapy are also at increased risk of bleeding. We investigated the use of a prothrombin complex concentrate (PCC; Beriplex P/N, CSL Behring, Marburg, Germany) to treat severe bleeding in a variety of settings: cardiac surgery, warfarin therapy and other surgery.
Thirty consecutive patients who had received PCC were identified from blood transfusion records. For cardiac surgery and warfarin reversal, PCC was administered in accordance with hospital protocols. PCC was administered to cardiac and other surgical patients responding poorly to recognized blood products, whereas it was administered first-line to patients with life-threatening bleeds and requiring warfarin reversal, in accordance with British Committee for Standards in Haematology guidelines. We conducted a retrospective analysis of patient records in order to ascertain PCC dose, use of other blood products and response to PCC (clotting screen results before and after PCC administration, haemostasis achievement, and survival).
Six patients (20%) were excluded because of inadequate documentation (n = 5) or acquired haemophilia (n = 1). Therefore, 24 patients were included in the analysis: coronary artery bypass graft (n = 5), mitral/aortic valve replacement (n = 2), other surgery (n = 9) and warfarin reversal (n = 8). Most patients (83.3%) received no more than 1500 IU of Beriplex P/N 500. Considerable reduction in administration of other blood products was seen during the 24 hours after PCC administration. Partial or complete haemostasis was achieved in 14 out of 18 cases (77.8%). In total, 12 out of 24 patients (50%) died during the study; two-thirds of the deaths were considered unrelated to bleeding. No thrombotic complications or adverse drug reactions were observed.
This study emphasizes the value of PCC in reversing the effects of oral anticoagulant therapy in bleeding patients. It also demonstrates the potential value of PCC in controlling bleeding in patients undergoing cardiac and other surgical procedures. The use of PCC in bleeding patients without hereditary or anticoagulation-related coagulopathy is novel, and further investigation is warranted. In the future, it may be possible to use PCC as a substitute for fresh frozen plasma in this setting; adequate documentation is crucial for all blood products.
Repair of thoracic aortic aneurysm (TAA) is often associated with massive hemorrhage aggravated by dilutional coagulopathy with severe hypofibrinogenemia. Although only fresh frozen plasma (FFP) is available for acquired hypofibrinogenemia in Japan, the hemostatic effect of FFP has not been enough for dilutional coagulopathy in TAA surgery. There are increasing reports suggesting that fibrinogen concentrate may be effective in controlling perioperative bleeding and reducing transfusion requirements.
We retrospectively analyzed the hemostatic effect of fibrinogen concentrate compared with FFP in total 49 cases of elective TAA surgery. In 25 patients, fibrinogen concentrate was administered when the fibrinogen level was below 150 mg/dL at the cardiopulmonary bypass (CPB) termination. The recovery of fibrinogen level, blood loss, and transfused units during surgery were compared between cases of this agent and FFP (n = 24).
We observed rapid increases in plasma fibrinogen level and subsequent improvement in hemostasis by administration of fibrinogen concentrate after CPB termination. The average volume of total blood loss decreased by 64% and the average number of transfused units was reduced by 58% in cases of fibrinogen concentrate given, in comparison with cases of only FFP transfused for fibrinogen supplementation.
In patients showing severe hypofibrinogenemia during TAA surgery, timely administration of fibrinogen concentrate just after removal from CPB is effective for hemostasis, and therefore in reducing blood loss and transfused volumes.
Massive hemorrhage; Thoracic aortic aneurysm; Cardiopulmonary bypass; Dilutional coagulopathy; Hypofibrinogenemia
There is currently a contrast between the demonstrated benefits of fibrinogen concentrate in correcting bleeding and reducing transfusion, and its perceived thrombogenic potential. This analysis evaluates the effects of fibrinogen concentrate on coagulation up to 12 days after administration during aortic surgery.
We performed a post hoc analysis of a prospective, randomized, double-blind, controlled trial of fibrinogen concentrate as first-line haemostatic therapy in aortic surgery. After cardiopulmonary bypass (CPB) and protamine administration, subjects with coagulopathic bleeding received fibrinogen concentrate or placebo. The placebo group received allogeneic blood products, including fresh-frozen plasma (FFP; n=32); the fibrinogen concentrate group received fibrinogen concentrate alone (FC; n=14), or fibrinogen concentrate followed by allogeneic blood products (FC+FFP; n=15). Plasma fibrinogen, fibrin-based clotting (ROTEM®-based FIBTEM assay), and peri- and postoperative haematological and coagulation parameters were compared.
Plasma fibrinogen and FIBTEM maximum clot firmness (MCF) decreased ∼50% during CPB but were corrected by FC or FC+FFP. At last suture, the highest values for plasma fibrinogen (360 mg dl−1) and FIBTEM MCF (22 mm) were within normal ranges—below the acute phase increases observed after surgery. In patients receiving only FFP as a source of fibrinogen, these parameters recovered marginally by last suture (P<0.001 vs FC and FC+FFP). All groups displayed comparable haemostasis at 24 h post-surgery. Fibrinogen concentrate did not cause alterations of other haemostasis parameters.
Fibrinogen concentrate provided specific, significant, short-lived increases in plasma fibrinogen and fibrin-based clot firmness after aortic surgery.
blood coagulation tests; cardiopulmonary bypass; fibrin; fibrinogen; plasma
Many children with a congenital heart defect undergo surgical correction requiring cardiopulmonary bypass (CPB). One sixth of these patients take an angiotensin-converting enzyme inhibitor (ACEi) for heart failure treatment. The effect of ACE inhibition on the fibrinolytic and inflammatory response in children undergoing CPB is unknown. In adults, ACE inhibition attenuates the increase in plasminogen activator inhibitor-1 (PAI-1) following CPB whereas the effect on the interleukin (IL)-6 response is uncertain. This study tests the hypothesis that preoperative ACE inhibition attenuates postoperative PAI-1 and IL-6 expression following CPB in children.
Single center prospective randomized non-blinded study.
University-affiliated pediatric hospital.
Children undergoing elective surgical correction of a congenital heart defect requiring CPB and taking an ACEi.
Children were randomized to continue ACEi until the morning of surgery (ACEi group, N=11) or to discontinue therapy 72 hours prior to surgery (No ACEi group, N=9).
Measurement and Main Results
Blood samples were collected at baseline before CPB, at 30min of CPB, upon arrival to the ICU, and on postoperative day 1 (POD1). Baseline bradykinin concentrations were significantly higher and ACE activity significantly lower in the ACEi group compared to the no ACEi group (P=0.04 and P=0.001 respectively). PAI-1 antigen increased 15-fold following CPB and peaked on POD1 (from 4.6±1.2 to 67.7±9.5 ng/ml; P<0.001). POD1 PAI-1 antigen correlated significantly with CPB time (r2=0.40, P=0.03) and was significantly lower in the ACEi group compared to the no ACEi group (P=0.03). The pro-inflammatory markers IL-6 and IL-8, as well as the anti-inflammatory marker IL-10, increased significantly following CPB (all P<0.001). IL-6 concentrations were significantly higher in the ACEi group following CPB (P=0.02) even after controlling for potential confounding factors such as age, CPB time and transfusion volume.
ACE inhibition attenuates the increase in postoperative PAI-1 but enhances the IL-6 response in children undergoing CPB.
angiotensin converting enzyme; plasminogen activator; interleukin; pediatric surgery; acute kidney injury; cardiopulmonary bypass
Many centres avoid using cardiopulmonary bypass (CPB) for lung transplant due to concerns over aggravated lung reperfusion injury and excessive blood loss. We reviewed our 23-years’ experience of single lung transplantation.
A retrospective review of single lung transplants at our institution (1987–2010), examining differences in allograft function and postoperative complications between CPB and non-bypass (non-CPB) cases.
Two hundred and fifty-nine single lung transplants were undertaken. Fifty-three (20.5%) with CPB. There was no difference demographically between the two groups. No difference existed in preoperative PO2/FiO2. At 1 and 24 h, the postoperative PO2/FiO2 ratio was no different (mean 2.95 and 3.24 in non-CPB cases; 3.53 and 3.75 in CPB patients, P = 0.18 and P = 0.34, respectively). Extubation time was not influenced by the use of CPB. Postoperative blood loss was greater in the CPB group. The usage of fresh frozen plasma and platelets was similar (P = 0.64 and 0.41, respectively). More blood was transfused during postoperative care of CPB patients (P = 0.02).
Fears of poor postoperative lung function after CPB appear unfounded. We could detect no difference in function or extubation time. Although the use of CPB increases postoperative bleeding and the need for transfusion, it may be used safely to facilitate lung transplantation.
Lung transplant; Cardiopulmonary bypass
Numerous studies have supported the effectiveness of recombinant activated factor VII (rFVIIa) for the control of bleeding after cardiac procedures; however safety concerns persist. Here we report the novel use of intraoperative low-dose rFVIIa in thoracic aortic operations, a strategy intended to improve safety by minimizing rFVIIa exposure.
Between July 2005 and December 2010, 425 consecutive patients at a single referral center underwent thoracic aortic operations with cardiopulmonary bypass (CPB); 77 of these patients received intraoperative low-dose rFVIIa (≤60 μg/kg) for severe coagulopathy after CPB. Propensity matching produced a cohort of 88 patients (44 received intraoperative low-dose rFVIIa and 44 controls) for comparison.
Matched patients receiving intraoperative low-dose rFVIIa got an initial median dose of 32 μg/kg (interquartile range [IQR], 16–43 μg/kg) rFVIIa given 51 minutes (42–67 minutes) after separation from CPB. Patients receiving intraoperative low-dose rFVIIa demonstrated improved postoperative coagulation measurements (partial thromboplastin time 28.6 versus 31.5 seconds; p = 0.05; international normalized ratio, 0.8 versus 1.2; p < 0.0001) and received 50% fewer postoperative blood product transfusions (2.5 versus 5.0 units; p = 0.05) compared with control patients. No patient receiving intraoperative low-dose rFVIIa required postoperative rFVIIa administration or reexploration for bleeding. Rates of stroke, thromboembolism, myocardial infarction, and other adverse events were equivalent between groups.
Intraoperative low-dose rFVIIa led to improved postoperative hemostasis with no apparent increase in adverse events. Intraoperative rFVIIa administration in appropriately selected patients may correct coagulopathy early in the course of refractory blood loss and lead to improved safety through the use of smaller rFVIIa doses. Appropriately powered randomized studies are necessary to confirm the safety and efficacy of this approach.
Extracorporeal circulation induces hemostatic alterations that lead to inflammatory response (IR) and postoperative bleeding. Tranexamic acid (TA) reduces fibrinolysis and blood loss after cardiopulmonary bypass (CPB). However, its effects on IR and vasoplegic shock (VS) are not well known and elucidating these effects was the main objective of this study.
A case control study was carried out to determine factors associated with IR after CPB. Patients undergoing elective CPB surgery were randomly assigned to receive 2 g of TA or placebo (0.9% saline) before and after intervention. We performed an intention-to-treat analysis, comparing the incidence of IR and VS. We also analyzed several biological parameters related to inflammation, coagulation, and fibrinolysis systems. We used SPSS version 12.2 for statistical purposes.
In the case control study, 165 patients were studied, 20.6% fulfilled IR criteria, and the use of TA proved to be an independent protective variable (odds ratio 0.38, 95% confidence interval 0.18 to 0.81; P < 0.01). The clinical trial was interrupted. Fifty patients were randomly assigned to receive TA (24) or placebo (26). Incidence of IR was 17% in the TA group versus 42% in the placebo group (P = 0.047). In the TA group, we observed a significant reduction in the incidence of VS (P = 0.003), the use of norepinephrine (P = 0.029), and time on mechanical ventilation (P = 0.018). These patients showed significantly lower D-dimer, plasminogen activator inhibitor 1, and creatine-kinase levels and a trend toward lower levels of soluble tumor necrosis factor receptor and interleukin-6 within the first 24 hours after CPB.
The use of TA attenuates the development of IR and VS after CPB.
Trial registration number
New oral anticoagulants are effective alternatives to warfarin. However, no specific reversal agents are available for life-threatening bleeding or emergency surgery. Using a porcine model of trauma, this study assessed the ability of prothrombin complex concentrate (PCC), activated PCC (aPCC), recombinant FVIIa (rFVIIa) and a specific antidote to dabigatran (aDabi-Fab) to reverse the anticoagulant effects of dabigatran.
Dabigatran etexilate (DE) was given orally for 3 days (30 mg/kg bid) and intravenously on day 4 to achieve consistent, supratherapeutic concentrations of dabigatran. Blood samples were collected at baseline, after oral DE, after intravenous dabigatran, and 60 minutes post-injury. PCC (30 and 60 U/kg), aPCC (30 and 60 U/kg), rFVIIa (90 and 180 μg/kg) and antidote (60 and 120 mg/kg) were added to blood samples ex-vivo. Coagulation was assessed by thromboelastometry, global coagulation assays and diluted thrombin time.
Plasma concentrations of dabigatran were 380 ± 106 ng/ml and 1423 ± 432 ng/ml after oral and intravenous administration, respectively, and all coagulation parameters were affected by dabigatran. Both PCCs and aDabi-Fab, but not rFVIIa, reversed the effects of dabigatran on thromboelastometry parameters and prothrombin time. In contrast, aPTT was only normalised by aDabi-Fab. Plasma concentration (activity) of dabigatran remained elevated after PCC and rFVIIa therapy, but was not measureable after aDabi-Fab.
In conclusion, PCC and aPCC were effective in reducing the anticoagulant effects of dabigatran under different conditions, while aDabi-Fab fully corrected all coagulation measures and decreased the plasma concentration of dabigatran below the limit of detection. No significant effects were observed with rFVIIa.
In cardiopulmonary bypass (CPB) patients, fibrinolysis may enhance postoperative inflammatory response. We aimed to determine whether an additional postoperative dose of antifibrinolytic tranexamic acid (TA) reduced CPB-mediated inflammatory response (IR).
We performed a randomized, double-blind, dose-dependent, parallel-groups study of elective CPB patients receiving TA. Patients were randomly assigned to either the single-dose group (40 mg/Kg TA before CPB and placebo after CPB) or the double-dose group (40 mg/Kg TA before and after CPB).
160 patients were included, 80 in each group. The incident rate of IR was significantly lower in the double-dose-group TA2 (7.5% vs. 18.8% in the single-dose group TA1; P = 0.030). After adjusting for hypertension, total protamine dose and temperature after CPB, TA2 showed a lower risk of IR compared with TA1 [OR: 0.29 (95% CI: 0.10-0.83), (P = 0.013)]. Relative risk for IR was 2.5 for TA1 (95% CI: 1.02 to 6.12). The double-dose group had significantly lower chest tube bleeding at 24 hours [671 (95% CI 549-793 vs. 826 (95% CI 704-949) mL; P = 0.01 corrected-P significant] and lower D-dimer levels at 24 hours [489 (95% CI 437-540) vs. 621(95% CI: 563-679) ng/mL; P = 0.01 corrected-P significant]. TA2 required lower levels of norepinephrine at 24 h [0.06 (95% CI: 0.03-0.09) vs. 0.20(95 CI: 0.05-0.35) after adjusting for dobutamine [F = 6.6; P = 0.014 corrected-P significant].
We found a significant direct relationship between IL-6 and temperature (rho = 0.26; P < 0.01), D-dimer (rho = 0.24; P < 0.01), norepinephrine (rho = 0.33; P < 0.01), troponin I (rho = 0.37; P < 0.01), Creatine-Kinase (rho = 0.37; P < 0.01), Creatine Kinase-MB (rho = 0.33; P < 0.01) and lactic acid (rho = 0.46; P < 0.01) at ICU arrival. Two patients (1.3%) had seizure, 3 patients (1.9%) had stroke, 14 (8.8%) had acute kidney failure, 7 (4.4%) needed dialysis, 3 (1.9%) suffered myocardial infarction and 9 (5.6%) patients died. We found no significant differences between groups regarding these events.
Prolonged inhibition of fibrinolysis, using an additional postoperative dose of tranexamic acid reduces inflammatory response and postoperative bleeding (but not transfusion requirements) in CPB patients. A question which remains unanswered is whether the dose used was ideal in terms of safety, but not in terms of effectiveness.
Current Controlled Trials number
Cardiac surgery; Cardiopulmonary bypass; Fibrinolysis; Tranexamic acid; Inflammatory response; Bleeding
Glucocorticoids can reduce myocardial dysfunction associated with ischemia and reperfusion injury following cardiopulmonary bypass (CPB) and circulatory arrest. The hypothesis was that maintenance of cardiac function after CPB with methylprednisolone therapy results, in part, from preservation of myocyte calcium cycling.
Piglets (5–7 kg) underwent CPB and 120 min of hypothermic circulatory arrest with (CPB-GC) or without (CPB) methylprednisolone (30 mg·kg−1) administered 6 hr before and at CPB. Controls (No-CPB) did not undergo CPB or receive glucocorticoids (n=6 per treatment). Myocardial function was monitored in vivo for 120 min after CPB. Calcium cycling was analyzed using rapid line-scan confocal microscopy in isolated, fluo-3-AM-loaded cardiac myocytes. Phospholamban phosphorylation and sarco(endo)plasmic reticulum calcium-ATPase (SERCA2a) protein levels were determined by immunoblotting of myocardium collected 120 min after CPB. Calpain activation in myocardium was measured by fluorometric assay.
Preload recruitable stroke work in vivo 120 min after reperfusion decreased from baseline in CPB (47.4±12 vs 26.4±8.3 slope of the regression line, p<.05), but was not different in CPB-GC (41±8.1 vs 37.6±2.2, p=.7). In myocytes isolated from piglets, total calcium transient time remained unaltered in CPB-GC (368±52.5 msec) compared with controls (434.5±35.3 msec; p=.07), but was prolonged in CPB myocytes (632±83.4 msec; p<.01). Calcium transient amplitude was blunted in myocytes from CPB (757±168 nM) compared with controls (1127±126 nM, p<.05) but was maintained in CPB-GC (1021±155 nM, p>.05). Activation of calpain after CPB was reduced with glucocorticoids. Phospholamban phosphorylation and SERCA2a protein levels in myocardium were decreased in CPB compared with No-CPB and CPB-GC (p<.05).
The glucocorticoid-mediated improvement in myocardial function after CPB might be due, in part, to prevention of calpain activation and maintenance of cardiac myocyte calcium cycling.
ischemia/reperfusion; cardiopulmonary bypass; circulatory arrest; physiology/pathophysiology; neonate; calcium; calcium cycling; SERCA2a; phospholamban
Abnormal bleeding after cardiopulmonary bypass (CPB) may result from incomplete neutralization of heparin, increased fibrinolytic activity, consumption of coagulation factors, or from a reduction in the number of circulating platelets together with impairment of platelet function. Although researchers have reason to believe that hemostasis after CPB could be improved with prostacyclin (PGI2), a potent inhibitor of platelet aggregation, the drug's clear-cut benefits in this respect have not yet been confirmed.
After conducting an initial study concerning the fate of platelets during CPB, in which we determined that PGI2 had a protective effect, we investigated the effects of PGI2 infusion during CPB on postoperative blood loss in 554 open-heart surgery patients, 200 of whom underwent valve replacement, 200 of whom had coronary artery bypass grafting (CABG), and 154 of whom underwent repeat valve replacement or CABG. The patients were divided into 2 groups: 277 patients (the study group) received both heparin and PGI2 during CPB, whereas the remaining 277 patients (the control group) were given heparin alone.
Of the patients who underwent surgery for the first time, those treated with PGI2 had a reduced mean blood loss (p < 0.05 only in CABG patients) in comparison with those who received heparin alone. Of the patients who underwent redo operations, those who received PGI2 had a nonsignificant tendency toward reduced blood loss. The mean difference in blood loss between the study group and the control group had no clinical relevance, however, because it was less than the smallest practical unit of measurement (i.e., 1 unit of blood). (Texas Heart Institute Journal 1988; 15:86-90)
Cardiopulmonary bypass; prostaglandins X; platelet aggregation; hemostasis, surgical
The objective of this clinical trial is to study the effectiveness of administering recombinant activated factor VII (rFVIIa) in reducing the amount of bleeding and the need for homologous blood and products transfusion in cardiac surgical coronary revascularization procedures done under cardiopulmonary bypass (CPB).
In a randomized controlled prospective observational study, 30 patients were scheduled for elective cardiac revascularization under CPB. Patients were randomly allocated into two groups. In Group I (Control group), no rFVIIa was administered following CPB. In Group II (Study group), a dose of 90 ug/Kg of rFVIIa was administered following weaning off CPB. The total amount of chest tube drain during the 1st 24 h following surgery was recorded as well as the qualitative and quantitative assessments of homologous blood and products transfusion. Serial analysis of hematological parameters including hemoglobin level and coagulation test in a definite data points was done. T0=baseline readings prior to CPB, T1=off CPB after protamine administration and before administration of the study drug, T2=on Cardiac Intensive Care Unit (CICU) admission, T3=12 h post-CICU admission, and T4=24 h post-CICU admission.
Considering the total chest tube drainage, mean values showed statistically significant results with a P value of 0.001. Homologous blood and products transfusion were statistically lower in the study group. Regarding the mean values for hematological assessment, results showed statistically lower International Normalized Ratio values at CICU admission and 12 h post-CICU admission with a P value of 0.018 and 0.004, respectively. Also, the Partial Thromboplastin Time mean values were statistically lower at same timings with estimated P values of 0.04 and 0.001, respectively.
It is concluded that the prophylactic use of rFVIIa in patients undergoing coronary revascularization surgery under the management of CPB had a remarkable significant results on both the amount of post-operative bleeding and the amount of blood and products transfusion.
CABG; coronary revascularization; recombinant activated factor VII
Hypomagnesaemia is a common complication after cardiopulmonary bypass (CPB) and predisposes to the development of cardiac arrhythmias. Previous studies showed that intravenous magnesium reduces the incidence of postoperative cardiac arrhythmias but it also inhibits platelet function. Our aim was to compare the postoperative blood loss in patients not receiving magnesium after CPB with the group who received magnesium and to compare the requirement of blood, fresh frozen plasma (FFP) and platelets within 24 hours after surgery. This prospective randomized controlled study was conducted in 80 adult patients on oral aspirin undergoing elective CABG requiring CPB. Group A patients had not received magnesium infusion after recovery from CPB. Group B patients received magnesium infusion after recovery from CPB. Postoperative bleeding was assessed in both the groups. All the data were statistically analyzed. There was a insignificant increase in 24 hours postoperative drainage in magnesium recipient group compared to control group (p>0.05). Requirements of blood and blood products to maintain haematocrit and coagulation profile revealed insignificant (p > 0.05). Increase in requirement of PRC, FFP and platelets in magnesium recipient patients than the control group. Incidence of atrial fibrillation (Gr A 2.5%, Gr B 2.5%) and atrial extrasystoles (Gr A 2.5%, Gr B 10%) revealed comparable (p > 0.05) between the groups, but incidence of ventricular arrhythmias were significantly (p<0.05) high in the patients of Gr A(17.5%) than Gr B(5%). To conclude, magnesium may be administered to patients who continue pre-operative aspirin to undergo on-pump CABG surgery.
Aspirin; Magnesium; CPB; CABG; Postoperative bleeding
Excessive bleeding (EB) after cardiopulmonary bypass (CPB) may lead to increased mortality, morbidity, transfusion requirements and re-intervention. Less than 50% of patients undergoing re-intervention exhibit surgical sources of bleeding. We studied clinical and genetic factors associated with EB.
We performed a nested case-control study of 26 patients who did not receive antifibrinolytic prophylaxis. Variables were collected preoperatively, at intensive care unit (ICU) admission, at 4 and 24 hours post-CPB. EB was defined as 24-hour blood loss of >1 l post-CPB. Associations of EB with genetic, demographic, and clinical factors were analyzed, using SPSS-12.2 for statistical purposes.
EB incidence was 50%, associated with body mass index (BMI)< 26.4 (25–28) Kg/m2, (P = 0.03), lower preoperative levels of plasminogen activator inhibitor-1 (PAI-1) (P = 0.01), lower body temperature during CPB (P = 0.037) and at ICU admission (P = 0.029), and internal mammary artery graft (P = 0.03) in bypass surgery. We found a significant association between EB and 5G homozygotes for PAI-1, after adjusting for BMI (F = 6.07; P = 0.02) and temperature during CPB (F = 8.84; P = 0.007). EB patients showed higher consumption of complement, coagulation, fibrinolysis and hemoderivatives, with significantly lower leptin levels at all postoperative time points (P = 0.01, P < 0.01 and P < 0.01).
Excessive postoperative bleeding in CPB patients was associated with demographics, particularly less pronounced BMI, and surgical factors together with serine protease activation.
Cardiopulmonary bypass (CPB) is used increasingly to correct cyanotic heart defects during early infancy, but myocardial dysfunction is often seen after surgical repair. This study evaluates whether starting CPB at a conventional, hyperoxic pO2 causes an "unintentional" reoxygenation (ReO2) injury. We subjected 2-wk-old piglets to ventilator hypoxemia (FIO2 approximately 0.06, pO2 approximately 25 mmHg) followed by 5 min of ReO2 on CPB before instituting cardioplegia. CPB was begun in hypoxemic piglets by either abrupt ReO2 at a pO2 of 400 mmHg (standard clinical practice) or by maintaining pO2 approximately 25 mmHg on CPB until controlling ReO2 with blood cardioplegic arrest. The effects of abrupt vs. gradual ReO2 without surgical ischemia (blood cardioplegia) were also compared. Myocardial nitric oxide (NO) production (chemiluminescence measurements of NO2- + NO3-) and conjugated diene (CD) generation (spectrophotometric A233 measurements of lipid extracts) using aortic and coronary sinus blood samples were assessed during cardioplegic induction. 30 min after CPB, left ventricular end-systolic elastance (Ees, catheter conductance method) was used to determine cardiac function. CPB and blood cardioplegic arrest caused no functional or biochemical change in normoxic (control) hearts. Abrupt ReO2 caused a depression of myocardial function (Ees = 25 +/- 5% of control). Functional depression was relatively unaffected by gradual ReO2 without blood cardioplegia (34% recovery of Ees), and abrupt ReO2 immediately before blood cardioplegia caused a 10-fold rise in cardiac NO and CD production, with subsequent depression of myocardial function (Ees 21 +/- 2% of control). In contrast, controlled cardiac ReO2 reduced NO production 94%, CD did not rise, and Ees was 83 +/- 8% of normal. We conclude ReO2 injury is related to increased NO production during abrupt ReO2, nullifies the cardioprotective effects of blood cardioplegia, and that controlled cardiac ReO2 when starting CPB to correct cyanotic heart defects may reduce NO production and improve myocardial status postoperatively.
Prothrombin complex concentrates (PCC) are haemostatic blood preparations indicated for urgent anticoagulation reversal, though the optimal dose for effective reversal is still under debate. The latest generation of PCCs include four coagulation factors, the so-called 4-factor PCC. The aim of this study was to compare the efficacy and safety of two doses, 25 and 40 IU/kg, of 4-factor PCC in vitamin K antagonist (VKA) associated intracranial haemorrhage.
We performed a phase III, prospective, randomised, open-label study including patients with objectively diagnosed VKA-associated intracranial haemorrhage between November 2008 and April 2011 in 22 centres in France. Patients were randomised to receive 25 or 40 IU/kg of 4-factor PCC. The primary endpoint was the international normalised ratio (INR) 10 minutes after the end of 4-factor PCC infusion. Secondary endpoints were changes in coagulation factors, global clinical outcomes and incidence of adverse events (AEs).
A total of 59 patients were randomised: 29 in the 25 IU/kg and 30 in the 40 IU/kg group. Baseline demographics and clinical characteristics were comparable between the groups. The mean INR was significantly reduced to 1.2 - and ≤1.5 in all patients of both groups - 10 minutes after 4-factor PCC infusion. The INR in the 40 IU/kg group was significantly lower than in the 25 IU/kg group 10 minutes (P = 0.001), 1 hour (P = 0.001) and 3 hours (P = 0.02) after infusion. The 40 IU/kg dose was also effective in replacing coagulation factors such as PT (P = 0.038), FII (P = 0.001), FX (P <0.001), protein C (P = 0.002) and protein S (0.043), 10 minutes after infusion. However, no differences were found in haematoma volume or global clinical outcomes between the groups. Incidence of death and thrombotic events was similar between the groups.
Rapid infusion of both doses of 4-factor PCC achieved an INR of 1.5 or less in all patients with a lower INR observed in the 40 IU/kg group. No safety concerns were raised by the 40 IU/kg dose. Further trials are needed to evaluate the impact of the high dose of 4-factor PCC on functional outcomes and mortality.
Eudra CT number 2007-000602-73.
Cardiopulmonary bypass (CPB) protocols of the baboon (Papio cynocephalusanubis) are limited to obtaining experimental data without concern for long-term survival. In the evaluation of pulmonary artery tissue engineered heart valves (TEHV's), pediatric CPB methods are adapted to accommodate the animals' unique physiology enabling survival up to six months until elective sacrifice.
Aortic access was by a 14F arterial cannula and atrial access by a single 24F venous cannula. The CPB circuit includes a 3.3 L/min flow rated oxygenator, 1/4" X 3/8" arterial-venous loop, 3/8" raceway, and bubble trap. The prime contains 700 ml Plasma-lyte, 700 units heparin, 5 ml of 50% dextrose, and 20 mg amiodarone. Heparinization (200 u/kg) targets an activated clotting time of 350 seconds. Normothermic CPB was initiated at a 2.5 L/M2/min cardiac index with a mean arterial pressure of 55–80 mmHg. Weaning was monitored with transesophageal echo cardiogram. Post-CPB circuit blood is re-infused. Chest tubes were removed with cessation of bleeding. Extubation is performed upon spontaneous breathing. The animals were conscious and upright three hours post-CPB.
Bioprosthetic valves or TEHVs were implanted as pulmonary replacements in 20 baboons: weight = 27.5 ± 5.6 kg, height = 73 ± 7 cm, body surface area = 0.77 m2 ± 0.08, mean blood flow =1.973 ± 0.254 L/min, core temperature = 37.1 ± 0.1°C, CPB time = 60 ± 40 minutes. No acidosis accompanied CPB. Sixteen animals survived, 4 expired. Three died of right ventricular failure and one of an anaphylactoid reaction. Surviving animals had normally functioning replacement valves and ventricles.
Baboon CPB requires modifications to include high systemic blood pressure for adequate perfusion into small coronary arteries, careful CPB weaning to prevent ventricular distention, and drug and fluid interventions to abate variable venous return related to a muscularized spleno-splanchnic venous capacity.
Baboon; Tissue Engineered Heart Valve (TEHV); Right Ventricular Outflow Tract (RVOT); Pulmonary Valve; Cardiopulmonary Bypass (CPB); Subhuman Primates; Homografts; Allografts; Xenografts
Warfarin-associated intracerebral hemorrhage (W-ICH) is a severe type of stroke. There is no consensus on the optimal treatment for W-ICH. Using a mouse model, we tested whether the rapid reversal of anticoagulation using human prothrombin complex concentrate (PCC) can reduce hemorrhagic blood volume. Male CD-1 mice were treated with warfarin (2 mg/kg over 24 h), resulting in a mean (±s.d.) International Normalized Ratio of 3.5±0.9. First, we showed that an intravenous administration of human PCC rapidly reversed anticoagulation in mice. Second, a stereotactic injection of collagenase was administered to induce hemorrhage in the right striatum. Forty-five minutes later, the animals were randomly treated with PCC (100 U/kg) or saline IV (n = 12 per group). Twenty-four hours after hemorrhage induction, hemorrhagic blood volume was quantified using a photometric hemoglobin assay. The mean hemorrhagic blood volume was reduced in PCC-treated animals (6.5±3.1 μL) compared with saline controls (15.3±11.2 μL, P = 0.015). In the saline group, 45% of the mice developed large hematomas (i.e., > 15 μL). In contrast, such extensive lesions were never found in the PCC group. We provide experimental data suggesting PCC to be an effective acute treatment for W-ICH in terms of reducing hemorrhagic blood volume. Future studies are needed to assess the therapeutic potential emerging from our finding for human W-ICH.
anticoagulation; intracerebral hemorrhage; mouse model; warfarin
The arterial in line application of the leukocyte inhibition module (LIM) in the cardiopulmonary bypass (CPB) limits overshooting leukocyte activity during cardiac surgery. We studied in a porcine model whether LIM may have beneficial effects on cardiac function after CPB.
German landrace pigs underwent CPB (60 min myocardial ischemia; 30 min reperfusion) without (group I; n = 6) or with LIM (group II; n = 6). The cardiac indices (CI) and cardiac function were analyzed pre and post CPB with a Swan-Ganz catheter and the cardiac function analyzer. Neutrophil labeling with technetium, scintigraphy, and histological analyses were done to track activated neutrophils within the organs.
LIM prevented CPB-associated increase of neutrophil counts in peripheral blood. In group I, the CI significantly declined post CPB (post: 3.26 ± 0.31; pre: 4.05 ± 0.45 l/min/m2; p < 0.01). In group II, the CI was only slightly reduced (post: 3.86 ± 0.49; pre 4.21 ± 1.32 l/min/m2; p = 0.23). Post CPB, the intergroup difference showed significantly higher CI values in the LIM group (p < 0.05) which was in conjunction with higher pre-load independent endsystolic pressure volume relationship (ESPVR) values (group I: 1.57 ± 0.18; group II: 1.93 ± 0.16; p < 0.001). Moreover, the systemic vascular resistance and pulmonary vascular resistance were lower in the LIM group. LIM appeared to accelerate the sequestration of hyperactivated neutrophils in the spleen and to reduce neutrophil infiltration of heart and lung.
Our data provides strong evidence that LIM improves perioperative hemodynamics and cardiac function after CPB by limiting neutrophil activity and inducing accelerated sequestration of neutrophils in the spleen.
The return of extracorporeal circuit blood at the termination of cardiopulmonary bypass (CPB) is an important feature of blood conservation during cardiac surgery procedures globally. We report our initial clinical evaluation of the Hemobag system a blood-salvaging device designed for whole blood recovery of residual post-CPB volume.
Residual whole blood is hemoconcetrated through the multipass “recovery loop” circuit separate from the CPB and collected in the Hemobag System. This allows the surgeons to continue with surgery, decannulate, and administer protamine simultaneously while the Hemobag is in use and the CPB circuit remains safely primed. We have compared 25 patients receiving the Hemobag to a control group of 25 patients treated with the cell washer that represented our previous standard of care method of circuit blood-salvaging technique.
The Hemobag system provided significantly higher hemoglobin, hematocrit, fibrinogen, albumin, and total protein levels in the final product reducing the amount of wasted autologous blood cells. There were no device-related complications. There were no significant differences in terms of blood utilization, chest tube drainage and clinical outcomes over the entire postoperative period among groups.
These results suggest that the Hemobag system is a safe and efficient method to multipass hemoconcentrate the residual diluted blood of the CPB circuit. The Hemobag has demonstrated its ability to maximize the composition of the residual CPB volume to achieve the best possible post-CPB hemoglobin, plasma protein and coagulation factors profile for the patient respect to CW.
Ultrafiltration; MUF; Cardiopulmonary bypass; Autologous blood conservation; Cardiac surgery
Acute lung injury (ALI) induced by cardiopulmonary bypass (CPB, CPB-ALI) is a common and serious complication after cardiac surgery. And infants and young children are more prone to CPB-ALI. The purpose of this study was to investigate the perioperative changes of plasma gelsolin (pGSN) in patients below 3years of age with cardiac surgeries and CPB, and determine whether pGSN are associated with the occurrence and severity of CPB-ALI.
Seventy-seven consecutive patients ≤3 years of age with congenital heart diseases (CHD) performed on open heart surgery with CPB were finally enrolled, and assigned to ALI and non-ALI groups according to the American-European Consensus Criteria. Plasma concentrations of gelsolin and total protein were measured at following 8 time points: before CPB (a), after CPB (b), 2 hours after CPB (c), 6 hours after CPB (d), 12 hours after CPB (e), 24 hours after CPB (f), 48 hours after CPB (g) and 72 hours after CPB (h).
Twenty-seven (35.1%) patients developed CPB-ALI in the study, including eleven (14.3%) patients with ARDS. The earliest significant drop of pGSN and normalized pGSN (pGSNN) of ALI group both occurred at 6 hours after CPB (p = 0.04 and p < 0.01), which was much earlier than those of non-ALI group (48 hours, p = 0.03 and 24 hours, p < 0.01); PGSN of ALI group before CPB and 6 hours after CPB were both significantly lower than those of non-ALI group (p < 0.01); PGSNN of ALI group before CPB and 6 hours after CPB were both significantly lower than those of non-ALI group (p < 0.01, p = 0.04); PGSN before CPB was the only independent risk factor predicting the occurrence of CPB-ALI (OR, 1.023; 95% CI, 1.007-1.039; p < 0.01) with an AUC of 0.753 (95% CI, 0.626-0.880); The optimal cutoff value of pGSN before CPB was 264.2 mg/L, with a sensitivity of 58.3% and a specificity 94.7%. And lower pGSN before CPB was significantly associated with the severity of CS-AKI (r = −0.45, p < 0.01).
Patients developing CPB-ALI had lower plasma gelsolin reservoir and a much more amount and rapid consumption of plasma gelsolin early after operation. PGSN before CPB was an early and sensitive predictor of CPB-ALI in infants and young children undergoing cardiac surgery, and was negatively correlated with the severity of CPB-ALI.
Plasma gelsolin; Acute lung injury; Cardiac surgery; Cardiopulmonary bypass; Infant; Young children; Congenital heart disease
Haemodilution during resuscitation after massive haemorrhage may worsen the coagulopathy and perpetuate bleeding.
Materials and methods
Blood samples from healthy donors were diluted (30 and-60%) using crystalloids (saline, Ringer’s lactate, PlasmalyteTM) or colloids (6% hydroxyethylstarch [HES130/0.4], 5% human albumin, and gelatin). The effects of haemodilution on platelet adhesion (Impact R), thrombin generation (TG), and thromboelastometry (TEM) parameters were analysed as were the effects of fibrinogen, prothrombin complex concentrates (PCC), activated recombinant factor VII (FVIIa), and cryoprecipates on haemodilution.
Platelet interactions was already significantly reduced at 30% haemodilution. Platelet reactivity was not improved by addition of any of the concentrates tested. A decrease in TG and marked alterations of TEM parameters were noted at 60% haemodilution. HES130/0.4 was the expander with the most deleterious action. TG was significantly enhanced by PCC whereas rFVIIa only caused a mild acceleration of TG initiation. Fibrinogen restored the alterations of TEM parameters caused by haemodilution including those caused by HES 130/0.4. Cryoprecipitates significantly improved the alterations caused by haemodilution on TG and TEM parameters; the effects on TG disappeared after ultracentrifugation of the cryoprecipitates.
The haemostatic alterations caused by haemodilution are multifactorial and affect both blood cells and coagulation. In our in vitro approach, HES 130/0.4 had the most deleterious effect on haemostasis parameters. Coagulation factor concentrates did not improve platelet interactions in the Impact R, but did have favourable effects on coagulation parameters measured by TG and TEM. Fibrinogen notably improved TEM parameters without increasing thrombin generation, suggesting that this concentrate may help to preserve blood clotting abilities during haemodilution without enhancing the prothrombotic risk.
haemodilution; coagulation factor concentrates; platelet function; thrombin generation; thromboelastometry