Fibrinogen Concentration Significantly Decreases After On-Pump Versus Off-Pump Coronary Artery Bypass Surgery: A Systematic Point-of-Care ROTEM Analysis

Off-pump implantation of left ventricular assist device via minimally invasive left thoracotomy: Our single-center experience

Background

The aim of this study was to compare our experience of left ventricular assist device implantation via minimally invasive left thoracotomy with off-pump versus on-pump technique.

Methods

Between June 2013 and April 2020, nine patients (8 males, 1 female; mean age: 47±11.9 years; range, 30 to 61 years) who underwent off-pump left ventricular assist device implantation and nine patients (8 males, 1 female; mean age: 47±11.4 years; range, 29 to 60 years) who underwent on-pump minimally invasive left thoracotomy were retrospectively analyzed. Postoperative outcomes and mid-term results of both groups were evaluated.

Results

Outflow graft was anastomosed to the ascending aorta with J-sternotomy in all patients. The median duration of intubation and intensive care unit stay were one (IQR: 1.5) day and eight (IQR: 6.5) days in the off-pump group, respectively and one (IQR: 0) day and seven (IQR: 7) days in the on-pump group, respectively. Intra-aortic balloon pump was needed during the weaning of cardiopulmonary bypass in one (11%) of the patients in both groups. Postoperative right ventricular failure was observed in two (22%) patients in the offpump group who were treated medically and recovered. There was no need for revision due to bleeding or postoperative extracorporeal membrane oxygenator implantation in either group. In the off-pump group, three patients underwent heart transplantation after median 854 (IQR: 960) days. Three patients died one month, two and four years after implantation. Three patients were still alive with left ventricular assist device and were being uneventfully followed for 365, 400, and 700 days after implantation.

Conclusion

Off-pump technique is safe and feasible option for implantation of left ventricular assist device via minimally invasive left thoracotomy.

Off-Pump Coronary Artery Bypass Grafting; is it Still Relevant?

Off-pump Coronary Artery Bypass Grafting (OPCAB) experienced a resurgence in the 1980s -2000s and developed steadily with improvement of the instrumentation and techniques. However questions about graft patency and long-term survival of OPCAB patients still exist. This review attempts to explore the current relevance of OPCAB.

Fibrinogen and Bleeding in Adult Cardiac Surgery: A Review of the Literature

Background: Fibrinogen is a substrate for blood clots formation. In cardiac surgery, a number of different mechanisms lead to a decrease in fibrinogen levels and consequent impaired haemostasis. Patients undergoing cardiac surgery are therefore frequently exposed to blood loss and allogeneic blood transfusion, which are risk factors associated with morbidity and mortality. Thus, particular efforts in fibrinogen management should be made to decrease bleeding and the need for blood transfusion. Therefore, fibrinogen remains an active focus of investigations from basic science to clinical practice. This review aims to summarise the latest evidence regarding the role of fibrinogen and current practices in fibrinogen management in adult cardiac surgery. Methods: The PubMed database was systematically searched for literature investigating the role and disorders of fibrinogen in cardiac surgery and diagnostic and therapeutic procedures related to fibrinogen deficiency aimed at reducing blood loss and transfusion requirements. Clinical trials and reviews from the last 10 years were included. Results: In total, 146 articles were analysed. Conclusion: The early diagnosis and treatment of fibrinogen deficiency is crucial in maintaining haemostasis in bleeding patients. Further studies are needed to better understand the association between fibrinogen levels, bleeding, and fibrinogen supplementation and their impacts on patient outcomes in different clinical settings.

The role of exogenous Fibrinogen in cardiac surgery: stop bleeding or induce cardiovascular disease

The surgical treatment contributes to broad variety of cardiovascular diseases (CVD). Due to many involved factors in preoperative bleeding, it is almost difficult to perform better Haemostatic approach. Fibrinogen is a major blood glycoprotein and a coagulation factor which decreases postoperative bleeding. It has a potential role in platelet activation and bleeding inhibition; it may reflect the inflammatory responses and be related to the endothelial dysfunction. Fibrinogen can act as a pro-inflammatory element via increasing some inflammatory markers including IL-6, tumor necrosis factor-α (TNF-α), monocyte chemo attractant protein (MCP-1), macrophage inflammatory protein-1 (MIP-1a and b), matrix metalloproteinase (MMP-1 and MMP-9) and Toll-like Receptors (TLRs); through activation of these factors, fibrinogen may induce some inflammatory mechanisms such as focal adhesion kinase (FAK), mitogen-activated protein kinases (MAPK) and nuclear factor κB (NF-κB) pathways. It may cause endothelial dysfunction by increasing P and E-selection, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels which activate MAPK and NF-κB pathways. This factor is also associated with increased exocytosed von Willebrand factor (vWF) as well as activation of Rho-GTPase mechanism. All of these data demonstrate the dual role of fibrinogen in cardiac surgeries, bleeding inhibition and CVD. Therefore, identifying the CVD factors is helpful for designing preventive strategies and alternative drugs.

Investigating the Effect of Fibrinogen Injection on Bleeding in Coronary Artery Bypass Surgery: A Clinical Trial

Background

Prevention and optimal treatment of postoperative bleeding are of great clinical importance in various types of surgeries including coronary artery bypass graft (CABG). Reducing the amount of bleeding will reduce the complications subsequent to blood transfusion. The positive effects of coagulation factors, especially fibrinogen, after cardiovascular bypass could have beneficial effects due to reduced bleeding and less need for blood transfusion. However, different studies have reported controversial findings.

Objectives

The present study aimed to evaluate the effect of prophylactic administration of fibrinogen on blood loss in patients undergoing CABG surgery to achieve more accurate clinical outcomes.

Methods

This was a double-blind randomized clinical trial conducted on 36 patients hospitalized in Ahvaz Imam Khomeini Hospital for coronary artery bypass graft. Patients were randomized to receive either fibrinogen concentrate (n = 18) or placebo (n = 18). Hemoglobin, hematocrit, international normalized ratio, prothrombin time, partial thromboplastin time, and fibrinogen were checked preoperatively. The transfusion of allogeneic blood components and the volume of blood loss were recorded and compared between the groups.

Results

Prophylactic fibrinogen injection reduced the need for blood transfusion, blood products, and postoperative hypotension in the fibrinogen group when compared to the control group (P ≤ 0.005). There was a significant difference between the two groups in terms of the amount of bleeding during operation (P ≤ 0.005).

Conclusions

Fibrinogen plays a key role in preventing and stopping the bleeding. Accordingly, fibrinogen decreases bleeding and the need for paced cell in patients in CABG. Given the adverse outcomes of bleeding and coagulopathy in patients undergoing surgery, we conclude that the use of fibrinogen could be beneficial as a prophylactic in hemorrhagic surgery.

A Low-dose human fibrinogen is not effective in decreasing postoperative bleeding and transfusion requirements during cardiac surgery in case of concomitant clinical bleeding and low FIBTEM values: A retrospective matched study

Background

Studies evaluating the hemostatic effects of fibrinogen administration in cardiac surgery are not conclusive.

Aims

We investigated whether the use of a low-dose human fibrinogen in case of clinical bleeding after protamine administration and concomitant low FIBTEM values is effective in reducing postoperative bleeding. Secondary end-point was to investigate the consumption of allogeneic blood products.

Setting and Design

This was a retrospective matched study conducted at university hospital.

Materials and Methods

Among 2257 patients undergoing surgery with cardiopulmonary (CPB) bypass, 73 patients received a median dose of 1 g human fibrinogen (ROTEM-Fibri group). This group was matched with 73 patients who had not received human fibrinogen (control group) among 390 patients having undergone surgery at the moment FIBTEM analysis was unavailable.

Statistical Analysis

Matching was performed for the type and the presence of redo surgery. McNemar and Wilcoxon paired tests were used to respectively compare the categorical and quantitative variables.

Results

The CPB bypass time was significantly higher in the ROTEM-Fibri group (P = 0.006). This group showed significantly higher bleeding in the first 12 and 24 h postoperatively (P < 0.001) and required significantly more transfusion of blood products (P < 0.001) and surgical revision (P = 0.007) when compared with the control group. There was no significant difference in the number of thromboembolic complications.

Conclusions

These results show that the administration of 1 g of fibrinogen based on low-FIBTEM values and clinical bleeding after protamine administration does not stop bleeding and the need for transfusion of allogeneic blood products.

FIBTEM as a predictor of intra- and postoperative blood loss in revision total hip arthroplasty: A prospective observational study

Revision total hip arthroplasty (THA) may cause intra- and postoperative massive bleeding. This prospective observational study evaluated if the maximum clot firmness of FIBTEM (MCFFIB) could act as a predictor of perioperative massive bleeding in revision THA.Fifty-eight adult patients undergoing revision THA were included. Pre- and postoperative MCFFIB, hematological and hemostatic laboratory data, as well as the amount of intra- and postoperative blood loss (IBL and PBL) were obtained.The change rate (MCFFIB-C) between the pre- and postoperative MCFFIB had a significant correlation with IBL (ρ = 0.431, P = .001). Moreover, PBL had a significant correlation with MCFFIB-C (ρ = 0.292, P = .026). The MCFFIB-C cut-off value of ≥ 29% showed the highest sensitivity and specificity for predicting IBL ≥ 1000 mL or PBL ≥500 mL. The incidence of red blood cell transfusion in the postoperative period was higher in patients showing MCFFIB-C ≥ 29% (34% vs 8%, P = .015).The change rate between pre- and postoperative MCFFIB values was correlated well with the amount of IBL or PBL. Moreover, particular change rate of MCFFIB could predict massive bleeding in revision THA.

Short-Term Experience with Off-Pump Versus On-Pump Implantation of the HeartWare Left Ventricular Assist Device

Implantation of left ventricular assist devices while avoiding cardiopulmonary bypass (CPB) may decrease bleeding and improve postoperative recovery. To understand the effectiveness of this approach, we reviewed the charts of 26 patients who underwent HeartWare left ventricular assist device (HVAD) implantation without use of CPB (off-CPB group) and 22 patients who had HVAD implanted with CPB (CPB group) with an emphasis on the 30 day postoperative period. Preoperatively, both groups had similar demographic, functional, and hemodynamic characteristics. Off-CPB patients had significantly shorter surgery times than CPB patients, 188.5 (161.5-213.3) min versus 265.0 (247.5-299.5) min, respectively; p < 0.001. Blood transfusion requirements during surgery and within the postoperative 48 hour period were significantly lower in the off-CPB group than in the CPB group (odds ratio: 5.9; 95% confidence interval: 1.1-31.1, p = 0.042). Compared with the CPB group, the off-CPB group patients had a shorter intubation time, 21 (17.4-48.5) hours versus 41 (20.6-258.4) hours; p = 0.042. Intensive care unit stay was 7.0 (4.75-13.5) days for off-CPB versus 10.0 (6.0-19.0) days for CPB (p = 0.256). The off-CPB approach allows HVAD to be implanted quickly with significantly less perioperative bleeding and transfusion requirements and facilitates postoperative rehabilitation.

Comparison of Thrombelastography-Derived Fibrinogen Values at Rewarming and Following Cardiopulmonary Bypass in Cardiac Surgery Patients

BACKGROUND

The inflated costs and documented deleterious effects of excess perioperative transfusion have led to the investigation of targeted coagulation factor replacement strategies. One particular coagulation factor of interest is factor I (fibrinogen). Hypofibrinogenemia is typically tested for using time-consuming standard laboratory assays. The thrombelastography (TEG)-based functional fibrinogen level (FLEV) provides an assessment of whole blood clot under platelet inhibition to report calculated fibrinogen levels in significantly less time. If FLEV values obtained on cardiopulmonary bypass (CPB) during rewarming are similar to values obtained immediately after the discontinuation of CPB, then rewarming values could be used for preemptive ordering of appropriate blood product therapy.

METHODS

Fifty-one cardiac surgery patients were enrolled into this prospective nonrandomized study to compare rewarming fibrinogen values with postbypass values using TEG FLEV assays. Baseline, rewarming, and postbypass fibrinogen values were recorded for all patients using both standard laboratory assay (Clauss method) and FLEV. Mixed-effects regression models were used to examine the change in TEG FLEV values over time. Bland-Altman analysis was used to examine bias and the limits of agreement (LOA) between the standard laboratory assay and FLEVs.

RESULTS

Forty-nine patients were included in the analysis. The mean FLEV value during rewarming was 333.9 mg/dL compared with 332.8 mg/dL after protamine, corresponding to an estimated difference of -1.1 mg/dL (95% confidence interval [CI], -25.8 to 23.6; P = 0.917). Rewarming values were available on average 47 minutes before postprotamine values. Bland-Altman analysis showed poor agreement between FLEV and standard assays: mean difference at baseline was 92.5 mg/dL (95% CI, 71.1 to 114.9), with a lower LOA of -56.5 mg/dL (95% CI, -94.4 to -18.6) and upper LOA of 242.4 mg/dL (95% CI, 204.5 to 280.3). The difference between assays increased after CPB and persisted after protamine administration.

CONCLUSIONS

Our results revealed negligible change in FLEV values from the rewarming to postbypass periods, with a CI that does not include clinically meaningful differences. These findings suggest that rewarming samples could be utilized for ordering fibrinogen-specific therapies before discontinuation of CPB. Mean FLEV values were consistently higher than the reference standard at each time point. Moreover, bias was highly heterogeneous among samples, implying a large range of potential differences between assays for any 1 patient.

Anesthetic Management for Left Ventricular Assist Device Implantation Through Left Thoracotomy: Evaluation of On-Pump Versus Off-Pump

BACKGROUND

Ventricular assist devices (VADs) are alternative approaches to medical treatment in patients with acute or chronic heart failure. The goal of this study was to compare an anesthetic approach in patients undergoing implantation of a VAD with (on-pump) or without (off-pump) cardiopulmonary bypass (CPB) through left thoracotomy.

METHODS

A total of 32 patients were divided into 2 groups: on-pump (group 1) and off-pump (group 2). A standard anesthesia protocol was used in all patients. Baseline characteristics of the patients, intraoperative hemodynamic and respiratory variables, anesthetic agents and vasoactive drugs administered, the amount of blood products, extubation, length of hospital stay and intensive care unit stay, and postoperative complications were recorded.

RESULTS

Patients' mean age was 54.7 ± 13.3 years (range, 18-74 years). Eighteen patients underwent surgery with CPB. Demographic data of the patients, preoperative characteristics, intraoperative use of blood products, intraoperative complications, and anesthetic drugs used were similar between groups (P > .05). The duration of surgery (219 ± 23 vs 273 ± 56 minutes) and anesthesia (274 ± 38 vs 323 ± 57 minutes) were shorter in group 2; there was no difference between the 2 groups in terms of mechanical ventilation time, length of stay in the intensive care unit, and length of hospital stay. There was no decrease in postoperative oxygen parameters and an increase in patient lactate levels with the use of CPB. The use of fresh frozen plasma and platelet suspension in the postoperative period was significantly higher in group 1 (P < .05). The rate of complications and mortality rate were comparable between the 2 groups (P > .05).

CONCLUSIONS

Our study results show that the use of CPB during VAD implantation via left thoracotomy increases operation time and use of blood products, while causing no change in the rate of complications.

Utility of Measurement of Serum Lactate in Diagnosis of Coagulopathy Associated with Peripheral Circulatory Insufficiency: Retrospective Evaluation Using Thromboelastometry from a Single Center in Japan

Recently, serum lactate level rather than systolic blood pressure (sBP) has been widely used to diagnose peripheral circulatory insufficiency, which often leads to coagulopathy with systemic inflammation. However, most of the reported disorders were examined by plasma samples. The aim of this study was to evaluate the utility of serum lactate for detecting coagulopathy with circulatory failure by using thromboelastometry as well as standard coagulation test. 192 adult patients transported to our hospital between January 2013 and September 2014 were enrolled in this retrospective study. The sBP, serum lactate and thromboelastometry (ROTEM(®)) were measured in these patients in the emergency department. All patients were divided into three groups based on serum lactate levels: (1) the severe group (≥4 mmol/L, n=41); (2) the mild group (<4 mmol/L and ≥2 mmol/L, n=59); and (3) the normal group (<2 mmol/L, n=92). Patients in the severe group were of a significantly younger age but had lower pH and poor outcome. SBP was significantly lower and heart rates were higher in the severe group than in the other groups. Prolonged PT-INR and APTT were statistically confirmed in the severe group. ROTEM findings in the severe group revealed significantly lower alpha angle, shortened Lysis Onset Time and significantly more cases exhibited hyperfibrinolysis. The same analysis with the cut-off level of sBP at 90 mmHg showed no significant difference in ROTEM findings between the two groups. Abnormal serum lactate levels (≥4.0 mmol/L) properly reflected peripheral circulatory insufficiency and were more closely associated with coagulopathy such as hyperfibrinolysis and hypocoagulability than sBP.

What factor within the Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) criteria is most strongly correlated with trauma induced DIC? A retrospective study using thromboelastometry in a single center in Japan

Purpose

The diagnostic criteria for disseminated intravascular coagulation (DIC) established by the Japanese Association for Acute Medicine (JAAM) is able to diagnose DIC accurately and promptly. The aim of this retrospective study is to evaluate the degree of association between each parameter of JAAM DIC criteria and the diagnosis of trauma induced DIC (T-DIC) utilizing thromboelastometry (ROTEM).

Methods

Trauma patients transported to our hospital with ROTEM performed in the emergency department between January 2013 and December 2015 were enrolled in this study. We evaluated (1) the characteristics of T-DIC, (2) the relationships between T-DIC and each parameter of the JAAM DIC criteria and (3) the diagnostic accuracies of each parameter for T-DIC by statistical measurement.

Results

All 72 patients (21 T-DIC and 51 control) were included in primary analysis. T-DIC was significantly related to younger age, more severe trauma scores, more cases of massive transfusions, and remarkable coagulation abnormality detected by standard coagulation tests. In the cases of T-DIC, ROTEM showed longer clotting time, lower acceleration, lower clot firmness, and inhibited fibrinolysis in EXTEM/INTEM. Within the JAAM DIC score, PT-INR ≥1.2 was the most accurate factor for T-DIC diagnosis; sensitivity 60.0%, specificity 100.0%, and accuracy 88.7%. PT-INR ≥1.2 was statistically correlated with the JAAM DIC score (p < 0.001, r = 0.709). The univariate analysis based on 1.2 of PT-INR indicated statistical differences in most categories of ROTEM, which is similar to analysis performed for the presence and absence of T-DIC.

Conclusions

Among JAAM DIC criteria, the PT-INR ≥1.2 was the most accurate factor for both the diagnosis of T-DIC and the evaluation of its severity.

Use of extracorporeal membranous oxygenator in transcatheter aortic valve replacement

The superiority of transcatheter aortic valve replacement (TAVR) compared with medical therapy for patients with aortic stenosis (AS) who are not suitable candidates for surgery had been proven. Cardiopulmonary bypass (CPB) is rarely used in TAVR. Reports of early use of extracorporeal membranous oxygenator (ECMO) have promising outcomes. ECMO offers the option of cardiac support rescue in case of intraoperative hemodynamic instability and can be instituted in advance when hemodynamic instability is expected. Here we review the English literature about the use of ECMO in TAVR procedures, and discuss the indications and rationale for its use as well as its advantages.

Can rotational thromboelastometry predict septic disseminated intravascular coagulation?

Rotational thromboelastometry (ROTEM), known as point-of-care testing, has been incorporated into various kinds of postsurgical management. However, the utility of ROTEM for rapid diagnosis of sepsis-induced disseminated intravascular coagulation (DIC) has not been investigated. This retrospective study includes 13 sepsis patients who underwent ROTEM in our emergency department in 2013. All patients were divided into two groups on the basis of the presence of DIC diagnosed by the Japanese Association for Acute Medicine (JAAM) DIC score. We evaluated the demographics, clinical characteristics, laboratory data, ROTEM test and outcomes for each patient. The correlations between JAAM DIC score and significantly different parameters by univariate analysis and receiver operating characteristic (ROC) analysis were performed to assess the accuracy of the variables. There were seven and six patients in the DIC group and non-DIC group, respectively. The DIC group showed significantly longer prothrombin times, international normalized ratio of prothrombin time and clotting times (CTs) in the EXTEM test, and higher fibrinogen and fibrin degradation products and D-dimer. The CT in EXTEM test was correlated more with JAAM DIC score (r = 0.798), than the standard coagulation test. These parameters were accurate predictors in the diagnosis of septic DIC, with an AUC of 0.952, and a cut-off value of more than 46.0 s, resulting in a sensitivity of 100.0% and a specificity of 83.3%. CT in the EXTEM test was a single reliable indicator of sepsis-induced DIC diagnosed by the JAAM DIC score, and strongly associated with severity of DIC.

Off-pump coronary artery bypass: past, present and future of a controversial technology

PURPOSE OF REVIEW

This review will examine the current role of off-pump coronary artery bypass (OPCAB) surgery compared with on-pump coronary artery bypass (ONCAB) surgery for the revascularization of ischemic myocardium.

RECENT FINDINGS

Recent studies have confirmed earlier findings that OPCAB is associated with less grafts per patient and less complete revascularization, and increased incidence of recurrent angina and need for repeat revascularization procedures, and more frequent rehospitalization for cardiac-related issues. OPCAB does not prevent postoperative renal dysfunction and is associated with worse long-term outcomes. Hospital costs are not reduced and are increased in those OPCAB patients who require intraoperative conversion to ONCAB procedures; however, when multiple arterial grafts are used and a complete revascularization is performed, OPCAB outcomes are equivalent to those of ONCAB procedures.

SUMMARY

OPCAB should only be performed by surgeons experienced in this technique in patients in whom a complete revascularization can be achieved; preferably with multiple arterial grafts.

The effect of hyperglycemia on blood coagulation: In vitro, observational healthy-volunteer study using rotational thromboelastometry (ROTEM)

We performed a study to investigate whether contamination of hemostasis samples with a glucose-containing solution might generate spurious results in rotational thromboelastometry (ROTEM) tests.Venous blood was taken from 12 healthy volunteers and divided into 4 specimen bottles, which were contaminated with different concentrations (0%, 5%, 10%, and 20%) of glucose solution.Significant lengthening of INTEMCT was observed in the 10% and 20% groups compared with baseline values (7.7% and 9%, P = 0.041 and P = 0.037, respectively). INTEMCFT increased by 20.1% in the 20% group (P = 0.005). INTEMα-angle and INTEMMCF decreased by 3.9% and 2.7%, respectively, in the 20% group (P = 0.010 and P = 0.049, respectively). EXTEMCFT was prolonged significantly, by 10.2%, 15.5%, and 25.6%, in the 5%, 10%, and 20% groups, respectively (P = 0.004, P < 0.001, and P < 0.001, respectively). EXTEMα-angle decreased significantly by 1.9%, 3.2%, and 4.0% in the 5%, 10%, and 20% groups, respectively (P = 0.014, P = 0.001, and P = 0.005, respectively). EXTEMMCF decreased by 3.4% in the 20% group (P = 0.023). FIBTEMMCF decreased by 9.2% and 17.5% in the 10% and 20% groups, respectively (P = 0.019 and P = 0.021, respectively). A significant correlation was observed between standard glucose solution contamination in the specimens and percentage variation of EXTEMCFT, EXTEMMCF, and FIBTEMMCF.To obtain accurate data from the ROTEM test regarding the hemostatic status of patients, specimens with suspected or known contamination should not be analyzed.

The thromboelastometric discrepancy between septic and trauma induced disseminated intravascular coagulation diagnosed by the scoring system from the Japanese association for acute medicine

The aim of this study is to evaluate the hematological differences between septic and traumatic disseminated intravascular coagulation (DIC) using the rotational thromboelastometry (ROTEM).This retrospective study includes all sepsis or severe trauma patients transported to our emergency department who underwent ROTEM from 2013 to 2014. All patients were divided into 2 groups based on the presence of DIC diagnosed by the Japanese Association for Acute Medicine (JAAM) DIC score. We statistically analyzed the demographics, clinical characteristics, laboratory data, ROTEM findings (EXTEM and FIBTEM), and outcome.Fifty-seven patients (30 sepsis and 27 severe trauma) were included in primary analysis. Sepsis cases were significantly older and had higher systemic inflammatory response syndrome (SIRS) scores, whereas there were no significant differences in other parameters including Acute Physiology and Chronic Health Evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score. Twenty-six patients (14 sepsis and 12 severe trauma) were diagnosed with DIC. The Septic DIC (S-DIC) group was significantly older and had higher DIC scores than the traumatic DIC (T-DIC) group. Hematologic examination revealed significantly higher CRP, fibrinogen, lower FDP, DD, and higher FDP/DD ratio were found in the S-DIC group in comparison with the T-DIC group. ROTEM findings showed that the A10, A20, and MCF in the FIBTEM test were significantly higher in the S-DIC group. However, no statistical differences were confirmed in the LI30, LI45, and ML in EXTEM test.The plasma fibrinogen level and fibrinogen based clot firmness in whole-blood test revealed statistical significance between septic and traumatic DIC patients.

Implementing a Statistical Model for Protamine Titration: Effects on Coagulation in Cardiac Surgical Patients

OBJECTIVES

To implement a statistical model for protamine titration.

DESIGN

Prospective randomized trial.

SETTING

University hospital.

PARTICIPANTS

Sixty (n = 30+30) patients scheduled for elective coronary artery bypass surgery were randomly assigned to 2 groups.

INTERVENTIONS

Protamine dose calculated according to an algorithm established from a statistical model or to a fixed protamine-heparin dose ratio (1:1).

MEASUREMENTS AND MAIN RESULTS

Both groups demonstrated comparable patient demographics and intraoperative data. Coagulation effects were evaluated using rotational thromboelastometry. Using the statistical model reduced (p<0.01) the protamine dose from 426±43 mg to 251±66 mg, followed by significantly (p<0.01) shorter intrinsic clotting time (208±29 seconds versus 244±52 seconds) and stronger clot firmness (p = 0.01), and effects on indices of extrinsic or fibrinogen coagulation pathways were insignificant. Test of residual heparin was negative in all patients after protamine administration, aligned with insignificant (p = 0.27) intergroup heparinase-verified clotting time differences.

CONCLUSIONS

The statistical model for protamine titration is clinically feasible and protects the patient from exposure to excessive doses of protamine, with advantageous effects on coagulation as measured using rotational thromboelastometry. Significance regarding clinical outcome is yet to be defined.

New horizons of non-emergent use of extracorporeal membranous oxygenator support

The expansion of the extra corporeal membrane oxygenation (ECMO) use and its indication is strikingly increased in the past few years. ECMO use expanded to lung transplantation, difficult general thoracic resections, transcatheter aortic valve replacement (TAVR) and LVAD implantation. Here we will discuss the indications and the outcomes of non-emergent use of ECMO.

A new modified animal model of myosin-induced experimental autoimmune myositis enhanced by defibrase

INTRODUCTION

We investigated the effect of defibrase (a proteolytic enzyme extraction of Agkistrodon halys venom) on experimental autoimmune myositis (EAM) in guinea pigs and explored the option of using a modified pig model of EAM to enhance the study of this disease.

MATERIAL AND METHODS

Guinea pigs were divided into 3 groups: group A (control group) was immunized with complete Freund adjuvant (CFA), then received 6 injections of saline weekly; group B (EAM group) was immunized with partially purified rabbit myosin emulsified with CFA, then received an injection of saline; group C (EAM + defibrase group) was immunized with purified rabbit myosin emulsified with CFA, then received an injection of defibrase. The animals were observed for their general health condition and the body weight was measured daily. Plasma levels of fibrinogen and creatine kinase (CK) were determined. Muscle tissues were examined histologically.

RESULTS

After immunizations for 6 weeks, incidence of EAM in groups A, B and C was 0 (0/7), 83.3% (10/12) and 100% (15/15), respectively. Guinea pigs with EAM presented angeitis symptoms of muscle weakness. Histological analysis revealed a significant difference. Muscles with EAM had scattered or diffuse inflammatory manifestations, which are also common pathological features of human idiopathic polymyositis (IPM). Defibrase-treated animals displayed extensive inflammation and fiber necrosis compared with the EAM group (histological score: 2.80 ±1.15 vs. 1.88 ±1.32, p < 0.05). Severity of inflammation of group B was mainly mild to moderate; 16.7% (2/12) of animals developed severe inflammation. Incidence of severe inflammation with a score up to 4 in group C was 40% (6/15).

CONCLUSIONS

Defibrase can exacerbate myosin-induced EAM; thus a new modified model was generated.

Minimally invasive is the future of left ventricular assist device implantation

There have been many factors that have allowed for progressive improvement in outcomes and lower complication rates. These include the improvement in left ventricular assist device (LVAD) technologies, combined with better understanding of patient management, all these. Nowadays the numbers of LVAD implantations exceed the number of annual heart transplants worldwide. Minimally invasive procedures are shown to improve the surgical outcome in both LVAD insertion and replacement. These minimally invasive techniques can be grouped grossly into shifting from on-pump to off-pump implantation, alternative access for implantation other than sternotomy, and a combination of both, which should be the ultimate aim of minimally invasive LVAD implantation. Here we describe the alternative techniques and configurations of minimally invasive and sites of implantation.

Prediction of Post-Weaning Fibrinogen Status during Cardiopulmonary Bypass: An Observational Study in 110 Patients

Background

After cardiac surgery with cardiopulmonary bypass (CPB), acquired coagulopathy often leads to post-CPB bleeding. Though multifactorial in origin, this coagulopathy is often aggravated by deficient fibrinogen levels.

Objective

To assess whether laboratory and thrombelastometric testing on CPB can predict plasma fibrinogen immediately after CPB weaning.

Patients / Methods

This prospective study in 110 patients undergoing major cardiovascular surgery at risk of post-CPB bleeding compares fibrinogen level (Clauss method) and function (fibrin-specific thrombelastometry) in order to study the predictability of their course early after termination of CPB. Linear regression analysis and receiver operating characteristics were used to determine correlations and predictive accuracy.

Results

Quantitative estimation of post-CPB Clauss fibrinogen from on-CPB fibrinogen was feasible with small bias (+0.19 g/l), but with poor precision and a percentage of error >30%. A clinically useful alternative approach was developed by using on-CPB A10 to predict a Clauss fibrinogen range of interest instead of a discrete level. An on-CPB A10 ≤10 mm identified patients with a post-CPB Clauss fibrinogen of ≤1.5 g/l with a sensitivity of 0.99 and a positive predictive value of 0.60; it also identified those without a post-CPB Clauss fibrinogen <2.0 g/l with a specificity of 0.83.

Conclusions

When measured on CPB prior to weaning, a FIBTEM A10 ≤10 mm is an early alert for post-CPB fibrinogen levels below or within the substitution range (1.5–2.0 g/l) recommended in case of post-CPB coagulopathic bleeding. This helps to minimize the delay to data-based hemostatic management after weaning from CPB.

Minimally invasive and alternative approaches for long-term LVAD placement: the Vanderbilt strategy

BACKGROUND

Minimally invasive and alternative strategies for implantation have been anecdotally reported for contemporary continuous-flow left ventricular assist device (CF-LVAD) placement.

METHODS

We reviewed our experience at a single center with alternative strategies for implantation of the HeartMate II and HeartWare CF-LVADs, in patients with advanced heart failure (HF). This featured article focuses on the associated surgical techniques and patient management pitfalls.

RESULTS

For appropriately selected cases, our group believes that these alternative strategies allow for the development of novel and less traumatic surgical approaches for CF-LVAD implantation. With reproducible outcomes, these approaches also promise the possibility of increasing the number of high-risk surgical patients who could benefit from CF-LVAD therapies.

CONCLUSIONS

This work has detailed a variety of less invasive alternative strategies for implantation of long-term LVADs. These newer approaches have the potential for significant advancements in the field of cardiothoracic surgery. Large-scale collaborative studies will be needed to clarify the potential advantages and disadvantages of these novel techniques on patient outcomes.