Intraoperative use of recombinant activated factor VII during complex aortic surgery

Recombinant Activated Factor VII (rFVIIa) for Bleeding After Thoracic Aortic Surgery: A Scoping Review of Current Literature

BACKGROUND

Bleeding after surgery on the thoracic aorta is a frequent complication, and can be associated with a significant increase in morbidity and mortality. Recombinant activated factor VII (rFVIIa) was developed initially for treating patients with hemophilia; however, it has been used increasingly "off-label" to achieve hemostasis after thoracic aortic procedures.

OBJECTIVE

This scoping review aimed to present the available literature on the role of rFVIIa in the management of refractory postoperative bleeding after thoracic aortic surgery.

METHODS/RESULTS

An electronic database search was conducted using Medline, Embase, Cochrane Library, and Google Scholar in June 2023. The authors included studies that reported the use of rFVIIa in patients undergoing surgical repair of ascending or descending aortic aneurysm or dissection. Single-case reports were excluded. Ten publications with a pooled number of 649 patients (319 patients received rFVIIa and 330 in the control groups) were identified: 3 case series, 6 retrospective studies, and 1 nonrandomized clinical trial. All studies reported the potential role of rFVIIa in correcting coagulopathy and reducing postoperative blood loss in this group of patients. Overall, there was not enough evidence to suggest that rFVIIa was associated with higher rates of thromboembolic complications or mortality.

CONCLUSION

Limited evidence suggests that rFVIIa may be useful in managing postoperative refractory bleeding in patients undergoing thoracic aortic surgery. However, the impact of rFVIIa on thromboembolic complications and mortality rates remains unclear.

Immobilization of blood coagulant factor VII on polycaprolactone membrane through polydopamine grafting

Postoperative bleeding following cardiac surgeries is still an issue that deranges the medical resources and cost. The oral and injection administrations of blood coagulation protein, Factor VII (FVII), is effective to stop the bleeding. However, its short half-life has limited the effectiveness of this treatment and frequent FVII intake may distress the patients. Instead, incorporating FVII into synthetic biodegradable polymers such as polycaprolactone (PCL) that is commonly used in drug delivery applications should provide a solution. Therefore, this study aimed to immobilize FVII on PCL membranes through a cross-linkage polydopamine (PDA) grafting as an intermediate layer. These membranes are intended to provide a solution for cardiac bleeding in coagulating blood and sealing the sutured region. The membranes were evaluated in terms of its physio-chemical properties, thermal behavior, FVII release profile and biocompatibility properties. The ATR-FTIR was used to analyze the chemical functionalities of the membranes. Further validation was done with XPS where the appearances of 0.45 ± 0.06% sulfur composition and C-S peak have confirmed the immobilization of FVII on the PCL membranes. The cross-linked FVIIs were viewed in spherical immobilization on the PCL membranes with a size range between 30 and 210 nm. The surface roughness and hydrophilicity of the membranes were enhanced with a slight shift of melting temperature. The PCL-PDA-FVII0.03 and PCL-PDA-FVII0.05 membranes, with wide area of FVII immobilization released approximately only 22% of FVII into the solution within 60 days period and, it is found that the PCL-PDA-FVIIx membranes projected the Higuchi release model with non-Fickian anomalous transport. While the cytotoxic and hemocompatibility analyses showed advance cell viability, identical coagulation time and low hemolysis ratio on the PCL-PDA-FVIIx membranes. The erythrocytes were viewed in polyhedrocyte coagulated structure under SEM visualization. These results validate the biocompatibility of the membranes and its ability to prolong blood coagulation, thus highlighting its potential application as cardiac bleeding sealant.

Off-label Use of Recombinant Activated Factor VII for Cardiac Surgical Bleeding

Recombinant activated factor VII has been widely used in an off-label manner for cardiac surgical bleeding. Recent reports have administered recombinant activated factor VII earlier in the course of bleeding and at lower doses than initially reported. This review will discuss the history, mechanism, current recommendations for use, and recent data on the use of recombinant activated factor VII in cardiac surgical bleeding.

Factor eight inhibiting bypass activity for refractory bleeding in acute type A aortic dissection repair: A propensity-matched analysis

BACKGROUND

Perioperative bleeding and transfusion have been associated with adverse outcomes after cardiac surgery. The use of factor eight inhibiting bypass activity (FEIBA) in managing bleeding after repair of acute Stanford type A aortic dissection (ATAAD) has not previously been evaluated. We report our experience in utilizing FEIBA in ATAAD repair.

STUDY DESIGN AND METHODS

A retrospective review was undertaken of all consecutive patients who underwent repair of ATAAD between July 2014 and December 2019. Patients were divided into two groups, dependent upon whether or not they received FEIBA intraoperatively: "FEIBA" (n = 112) versus "no FEIBA" (n = 119). From this, 53 propensity-matched pairs of patients were analyzed with respect to transfusion requirements and short-term clinical outcomes.

RESULTS

Thirty-day mortality for the entire cohort was 11.7% (27 deaths), not significantly different between patient groups. Those patients who received FEIBA demonstrated reduced transfusion requirements for all types of blood products in the first 48 h after surgery as compared with the "no FEIBA" cases, including red blood cells, platelets, plasma, and cryoprecipitate (p < .0001). There was no significant difference in major postoperative morbidity between the two groups. The FEIBA cohort did not demonstrate an increased incidence of thrombotic complications (stroke, deep venous thrombosis, pulmonary thromboembolism).

DISCUSSION

When used as rescue therapy for refractory bleeding following repair of ATAAD, FEIBA appears to be effective in decreasing postoperative transfusion requirements whilst not negatively impacting clinical outcomes. These findings should prompt further investigation and validation via larger, multi-center, randomized trials.

Recombinant Activated Factor VII in Aortic Surgery for Patients Under Hypothermic Circulatory Arrest

Purpose

We aimed to identify the risk factors of critical bleeding and investigate the safety of recombinant activated factor VII (rFVIIa) in aortic surgery under hypothermic circulatory arrest (HCA).

Patients and Methods

The present single-center retrospective study compared the baseline characteristics of 144 patients who underwent aortic surgery under HCA at our institute. Among the total cohort of 144 patients, 42 received rFVIIa (rFVIIa group), while the remaining 102 patients did not (non-rFVIIa group). Perioperative bleeding and transfusions, postoperative 30-day mortality, and adverse events (AEs) were analyzed in 29 propensity score-matched pairs.

Results

Before surgery, the rFVIIa group demonstrated a greater number of shocks (p=0.019), higher JapanSCORE II mortality rate (p=0.033), low platelet count (p=0.015) and fibrinogen (p<0.001) level, prolonged activated partial thromboplastin time (aPTT) (p=0.005) and prothrombin time international normalized ratio (PT-INR) (p=0.006), and longer aortic cross clamp time (p=0.049). Postoperative bleeding, transfusion, 30-day mortality, and AEs were comparable between the groups both in the entire-unmatched cohort and propensity score matching cohort.

Conclusion

Preoperative shock, higher JapanSCORE II mortality rates, low platelet and fibrinogen levels, prolonged aPTT and PT-INR, and longer aortic clamping time might be risk factors for excessive bleeding and indicate the need for rFVIIa treatment. The present study suggests that rFVIIa can be safely used to address critical and continuous bleeding in spite of adequate transfusion and supplementation of other coagulation factors in aortic surgery under HCA, without an increase in 30-day mortality and AEs.

Efficacy, Safety, and Strategies for Recombinant-Activated Factor VII in Cardiac Surgical Bleeding: A Narrative Review

As perioperative bleeding continues to be a major source of morbidity and mortality in cardiac surgery, the search continues for an ideal hemostatic agent for use in this patient population. Transfusion of blood products has been associated both with increased costs and risks, such as infection, prolonged mechanical ventilation, increased length of stay, and decreased survival. Recombinant-activated factor VII (rFVIIa) first was approved for the US market in 1999 and since that time has been used in a variety of clinical settings. This review summarizes the existing literature pertaining to perioperative rFVIIa, in addition to society recommendations and current guidelines regarding its use in cardiac surgery.

Change of coagulation after NovoSeven® use for bleeding during cardiac surgery

Objectives Recombinant activated factor VII has been used for the treatment of hemophilia, factor VII deficiency, and Glanzmann's thrombasthenia. Off-label uses have recently been increasing, and there are reports that recombinant activated factor VII is effective for the treatment of excessive bleeding during or after cardiovascular surgery. We retrospectively reviewed the effectiveness of recombinant activated factor VII and its influence on the coagulation system as a treatment for uncontrollable bleeding during cardiovascular surgery. Methods Between April 2009 and May 2015, recombinant activated factor VII was used to treat uncontrollable bleeding during cardiovascular surgery in 17 patients at our hospital. The indications for recombinant activated factor VII administration were critical uncontrollable bleeding during surgery and normal platelet and fibrinogen levels. Results Blood loss significantly decreased in every case after recombinant activated factor VII administration ( p < 0.05). No adverse thromboembolic events were encountered. The prothrombin time-international normalized ratio, activated partial thromboplastin time, fibrin degradation product and D-dimer levels decreased significantly after recombinant activated factor VII administration. One day later, all blood coagulation test values were almost within the normal ranges. Conclusions Recombinant activated factor VII has a strong hemostatic action, but it is necessary to exclude surgical bleeding to exhibit the hemostatic effect. Administration that does not comply with the indications for recombinant activated factor VII may lead to serious complications such as thromboembolism. In properly selected patients, recombinant activated factor VII is an effective agent for the treatment of uncontrollable bleeding during cardiovascular surgery.

Recombinant activated factor VII for uncontrolled bleeding postcardiac surgery

A retrospective observational study to review the safety and efficacy of rFVIIa in persistent hemorrhage in post cardiac surgical patients.

Methods

Patients who had bleeding of 3 ml/kg/h or more for 2 consecutive hours after cardiac surgery were arranged into two groups; control group, who received conventional treatment and rFVIIa group, who received conventional treatment and rFVIIa.

Results

There was no significant difference in demographic and surgical characteristics of both groups. The chest tube output significantly decreased in the rFVIIa group compared to the other group 4 hours after admission {1.4 (IQR: 1–2.2) ml/kg/h vs 3.9 (IQR: 3.1–5.6) ml/kg/h; p = 0.004} and continues to be significant till 9 hours after CSICU admission {0.6 (IQR: 0.4–1.1) ml/kg/h vs 1.9 (IQR: 1.2–2.2) ml/kg/h; p = 0.04}. The median number of blood products units transfused to rFVIIa group was significantly lower compared to control group in the period from 3–12 hours after CSICU admission. 13 (5.5%) patients in rFVIIa group had Thromboembolic adverse events (TAE) compared to 7 (2.4%) patients in other group p = 0.27. 8 patients in the rFVIIa group needed reexploration compared to 19 patients in the other group, p = 0.01. No significant difference was noticed between the 2 groups regarding: new onset renal failure, median number of mechanical ventilator days, pneumonia, mediastinitis, ICU and hospital lengths of stay, survival at 30 days and at discharge.

Conclusion

In this analysis, rFVIIa succefully reduced the chest tube bleeding and blood products transfused during severe post cardiac surgical bleeding. However, safety of rFVIIa remains unclear. Prospective controlled trials are still needed to confirm the role of rFVIIa.

The Impact of a Blood Conservation Program in Complex Aortic Surgery

OBJECTIVE

Recent Society of Thoracic Surgeons and Society of Cardiovascular Anesthesiologists (STS/SCA) guidelines highlight the safety of blood conservation strategies in routine cardiac surgery. We evaluated the feasibility and impact of such a program in complex aortic surgery.

METHODS

Between March 2010 and October 2011, 63 consecutive aortic replacement procedures were performed: aortic root (n = 17; 27%), ascending aorta (n = 15; 23.8%), aortic arch (n = 19; 30.2%), descending aorta (n = 8; 12.7%), and thoracoabdominal aorta (n = 4; 6.3%). Aortic dissections were present in 32 patients. A multidisciplinary approach to blood conservation included minimal perioperative crystalloid, small priming circuits, hemoconcentration, meticulous hemostasis, and tolerance of postoperative anemia (hemoglobin of ≥ 7mg/dL).

RESULTS

Operative mortality was 11.1%. Multivariate predictors of mortality were low preoperative hematocrit (HCT, P = 0.05) and endocarditis (P = 0.021). Seventy-four percent of patients required no intraoperative packed red blood cell (pRBC) transfusion. For nondissection patients, 80.6% required ≤ 1 U of intraoperatively compared to 54.3% in STS benchmark data (P < 0.0001). During the hospital stay, 24 patients (39%) received no pRBCs and 34 patients (54%) received ≤ 1 U of pRBCs. Multivariate predictors of pRBC transfusion were low preoperative HCT (P = 0.04) and cardiopulmonary bypass time (P = 0.01). Discharge hemoglobin/HCT values were 8.7/26.3 compared to preoperative 12.1/35.5 (p < 0.001). Complications were absent in 94% (32/34) of patients receiving ≤1 U compared to 59% (17/29) in patients who received ≥ 2 U (P = 0.001).

CONCLUSIONS

These findings demonstrate that a perioperative blood conservation management strategy can be extended to complex aortic surgery and is associated with better clinical outcomes.