Meningiomas and hemorrhagic diathesis

Efficacy and Safety of Tranexamic Acid in Cancer Surgery. An Update of Clinical Findings and Ongoing Research

In cancer patients undergoing surgery, tumor biology and anticancer treatments can increase the risk of perioperative bleeding and blood transfusions. Notably, blood transfusions can be potentially associated with an increased risk of life-threatening immune responses, acute lung injury, postoperative infections, and thromboembolism. Moreover, the link between perioperative transfusion and increased risk of cancer recurrence cannot be excluded. On the other hand, cancer patients have an increased risk of thromboembolism due to cancer itself and antineoplastic systemic treatments including chemotherapy and anti-angiogenic drugs. In this complex scenario, effective and safe strategies aimed at the prevention of blood transfusions are warranted. This narrative review addresses the efficacy, and the safety of the synthetic antifibrinolytic agent tranexamic acid (TXA) when used perioperatively in cancer surgery. Although in not oncologic surgery the use of TXA has been extensively studied, in the setting of cancer patients requiring surgery, the evidence is scarce. An overview of the ongoing clinical research is also provided.

Intraoperative tranexamic acid use in patients undergoing excision of intracranial meningioma: Randomized, placebo-controlled trial

Background:

Intracranial meningioma resection is associated with substantial intraoperative bleeding. Intraoperative tranexamic acid (TXA) use can reduce bleeding in a variety of surgical procedures. The objective of this study was to evaluate the effects of TXA treatment on blood loss and transfusion requirements in patient undergoing resection of intracranial meningioma.

Methods:

We conducted a prospective, randomized double-blind clinical study. The patient scheduled to undergo excision of intracranial meningioma were randomly assigned to receive intraoperatively either intravenous TXA or placebo. Patients in the TXA group received intravenous bolus of 20 mg/kg over 20 min followed by an infusion of 1 mg/kg/h up to surgical wound closure. Efficacy was evaluated based on total blood loss and transfusion requirements. Postoperatively, thrombotic complications, convulsive seizure, and hematoma formation were noted.

Results:

Ninety-one patients were enrolled and randomized: 45 received TXA (TXA group) and 46 received placebo (group placebo). Total blood loss was significantly decreased in TXA group compared to placebo (283 ml vs. 576 ml; P < 0.001). Transfusion requirements were comparable in the two groups (P = 0.95). The incidence of thrombotic complications, convulsive seizure, and hematoma formation was similar in the two groups.

Conclusion:

TXA significantly reduces intraoperative blood loss, but did not significantly reduced transfusion requirements in adults undergoing resection of intracranial meningioma.

Usefulness of thromboelastography for perioperative evaluation of hemostatic profile in patients with primary brain tumors undergoing surgery

Context:

Hemostatic abnormalities are more common in patients with brain tumors than systemic malignant diseases. Conventional coagulation tests (CCT) are poor assays for dynamic assessment of clot strength in whole blood. Thromboelastography (TEG) gives us detailed information on the dynamics of clot development, stabilization, and dissolution reflecting in vivo hemostasis. TEG can assess both thrombosis and fibrinolysis.

Aims:

This study aimed to investigate the temporal trends in hemostatic profile occurring during surgery for primary brain tumors, using a combination of TEG and CCT, and to assess perioperative blood component support.

Subjects and Methods:

A prospective, observational study was done on 40 patients with primary brain tumors larger than 4 cm in maximum diameter on computed tomography or magnetic resonance imaging. The tests (TEG and CCT [PT, INR, activated partial thromboplastin time, and platelet count]) were performed preoperatively (on the day of surgery), intraoperatively (2 h into surgery), and postoperatively (the day after surgery).

Statistical Analysis:

SPSS Version 21.0 statistical analysis software was used.

Results:

We found a universal trend toward hypercoagulability (persistent decrease in R-time, K-time and increase in MA, α-angle, Coagulation Index) in all the TEG parameters measured intraoperatively and postoperatively even though the values were within normal limits. Results of CCT had poor correlation with TEG parameters. The mean intraoperative blood loss was 737.7 ± 185.6 mL, for which PRBC was transfused in 17 patients, FFP in 13, but no platelet transfusion was done intraoperatively.

Conclusions:

We found a trend toward hypercoagulability in our study in intraoperative and postoperative period using TEG which was not evident on CCT. TEG was a useful diagnostic tool to identify coagulation abnormalities and to guide perioperative blood transfusion.

Effect of tranexamic acid on intraoperative blood loss and transfusion requirements in patients undergoing excision of intracranial meningioma

Surgical excision of meningioma is often complicated by significant blood loss requiring blood transfusion with its attendant risks. Although tranexamic acid is used to reduce perioperative blood loss, its blood conservation effect is uncertain in neurosurgery. Sixty adults undergoing elective craniotomy for meningioma excision were randomized to receive either tranexamic acid or placebo, initiated prior to skin incision. Patients in the tranexamic acid group received intravenous bolus of 20mg/kg over 20min followed by an infusion of 1mg/kg/h till the conclusion of surgery. Intraoperative blood loss, transfusion requirements and estimation of surgical hemostasis using a 5-grade scale were noted. Postoperatively, the extent of tumor excision on CT scan and complications were observed. Demographics, tumor characteristics, amount of fluid infusion, and duration of surgery and anesthesia were comparable between the two groups. The amount of blood loss was significantly less in tranexamic acid group compared to placebo (830mlvs 1124ml; p=0.03). The transfusion requirement was less in tranexamic acid group (p>0.05). The patients in tranexamic acid group fared better on a 5-grade surgical hemostasis scale with more patients showing good hemostasis (p=0.007). There were no significant differences between the groups with regards to extent of tumor removal, perioperative complications, hospital stay or neurologic outcome. To conclude, administration of tranexamic acid significantly reduced blood loss in patients undergoing excision of meningioma. Fewer patients in the tranexamic acid group received blood transfusions. Surgical field hemostasis was better achieved in patients who received tranexamic acid.

Haemostatic changes during surgery for primary brain tumours

OBJECTIVE

Primary brain tumours may be associated with coagulation disorders which can pose intraoperative and postoperative management difficulties. The aim was to evaluate the coagulation profile of patients with brain tumours undergoing surgery using thromboelastography (TEG) in combination with simple laboratory tests.

METHODS

Fifty adult patients with primary brain tumours larger than 4 cm in maximum diameter and no history of coagulation disorders were studied in a prospective, observational manner over a one year period. Preoperative, intraoperative, and postoperative measurements included haemoglobin concentration, platelet count, prothrombin and partial thromboplastin times, fibrin(ogen) degradation product concentration, D-dimer concentration, and TEG.

RESULTS

Eleven patients (22%) had abnormal intraoperative TEGs, of whom six (12%) subsequently developed haematomas requiring surgical evacuation. The coagulopathy seemed to be hyperfibrinolysis in two cases (4%) and disseminated intravascular coagulation in four (8%). There was no preoperative difference in reaction time (R time) for clot formation between the non-haematoma and haematoma groups(mean 11.44 (SD 3.42) v 12.33 (2.50) min, P=0.46). However, when other preoperative indices were compared, in the non-haematoma group, K time (time to reach a clot amplitude of 20 mm) was shorter (6.72 (2.15) v 10.56 (3.50) min, P=0.001), rate of clot growth (å) was faster (43.67 degrees (7.53) v 27.11 degrees (5.42), P<0.0001) and maximum amplitude of clot strength (MA) was greater (52.64 (7.85) v 40.33 (6.59) mm, P<0.001). Intraoperatively, R time was significantly shortened in the non-haematoma group, (7.67 (1.78) min, P<0.0001) unlike the haematoma group (10.67 (1.58) minutes, P=0.11).

CONCLUSIONS

Although these results indicate a general hypercoagulability during brain tumour surgery, in certain cases, a predisposition towards hypocoagulability may exist even before surgery, detectable only when the physical characteristics of clot formation are studied by TEG. Judicious replacement of clotting factors, platelets, and antifibrinolytic agents should be considered intraoperatively if the TEG is abnormal, without waiting for laboratory test results.

Urokinase thrombolytic therapy of pulmonary embolism in neurosurgically treated patients

Pulmonary embolism (PE) is a severe complication in neurosurgery. The best treatment of PE is thrombolytic therapy, but the presence of either intracranial neoplasm or recent neurosurgical procedures is considered a major contraindication to this therapy. We have used urokinase thrombolytic therapy in nine of our patients with severe PE that occurred from 7 to 34 days after a neurosurgical operation. All patients survived. No intracranial hemorrhage occurred. We also advocate thrombolytic therapy for severe PE in patients who were recently operated on by neurosurgical procedure.

Haemostatic derangement in patients with intracranial tumours

Forty-five patients with brain tumours were studied for evidence of any haemostatic abnormalities in the preoperative and intraoperative period. An abnormality was found in 44 of the patients in the preoperative period and in all the patients during the operation. One patient developed acute disseminated intravascular coagulation. A change in the haemostatic abnormality from the preoperative to the intraoperative period was demonstrated in 9 of the patients. The histological nature of the tumour did not influence the haemostatic derangement. A shortened euglobulin lysis time, prolonged thrombin time, increased fibrin degradation products and abnormal fibrinogen levels were the common isolated abnormalities. When considered together, chronic disseminated intravascular coagulation (DIC) with or without fibrinolysis and fibrinolysis with or without DIC were the commonest abnormalities. Although some degree of haemostatic derangement is found in a high proportion of patients with brain tumours, clinically relevant abnormalities are rare.

Meningiomas

This article reviews the recent literature on the pathogenesis and pathology of meningiomas, contemporary techniques of surgical resection, and new nonsurgical treatments, including radiation and hormone therapy. Factors predisposing to meningioma formation include female sex, previous ionizing radiation, and Type 2 neurofibromatosis. The first factor may act through the expression of sex hormone receptors, especially the progesterone receptor, in these tumors; the other two probably act by causing a deletion on Chromosome 22. The pathological classifications of meningiomas include the traditional division into histological subtypes and the World Health Organization classification that selects characteristics that may lead to recurrence. There is an increasing emphasis on proliferative indices and other characteristics that may predict aggressive behavior in these tumors. On computed tomography, meningiomas are enhancing, well-marginated, dural-based lesions that may have considerable surrounding edema; the cause of the edema is uncertain but may result from secretory products of the tumor. Magnetic resonance imaging with enhancement will demonstrate these lesions accurately and can be used for three-dimensional reconstruction as well. Computed tomography and magnetic resonance imaging have largely replaced angiography in the preoperative diagnosis of meningiomas, but angiographic embolization may be a useful operative adjunct. Although meningioma surgery is sometimes thought of as benign and curative, the reported surgical mortality rate is as high as 14.3% and the reported 10-year survival rate after surgery varies from 43 to 77%. Surgery has advanced most in the management of suprasellar, cavernous sinus, clivus, tentorial, and posterior fossa meningiomas, because new approaches and a better understanding of anatomy have allowed more radical resection. There is still substantial morbidity associated with surgery in these regions, however, and the long-term recurrence rates are still unknown for these new radical techniques. For convexity, parasagittal, lateral sphenoid wing, and olfactory groove meningiomas, complete resection should be the goal and operative morbidity appears to be low. There is a high recurrence rate after surgery. With apparent total removal, the recurrence rate varies from 9 to 20% at 10 years, with subtotal resection varying from 18.4 to 50%. The degree of resection appears to be most important in recurrence, but histopathological features are also important. Recently, radiation therapy has been recognized as a useful adjunct to surgery, and with radiosurgical techniques may become more important in the future. Antiprogesterone therapy appears to have had some success as well, and it or other hormonal therapy may be another future option for residual or recurrent meningiomas.

National survey of patterns of care for brain-tumor patients

An excellent response by participating institutions was realized in this survey of patterns of care for patients with primary brain tumors. Since the histopathology of the tumor is such a strong predictor of outcome and influences care so greatly, most analyses were performed not only on the overall series of patients but also by World Health Organization histological classification. Several factors that influence outcome were identified: tumor type, patient age, patient Karnofsky rating, tumor location, and therapy. Very few cases were coded as regards the American Joint Committee on Cancer clinical stage, and few potentially eligible cases were placed in investigative protocols. It behooves those centers providing investigative protocol opportunities to develop liaisons with practicing physicians nearby as well as at some distance and to provide an organizational framework that will make participation in these protocols practical for a larger segment of our brain-tumor patient population. Between 1980 and 1985, the increased use of magnetic resonance imaging in neuroradiology is apparent as well as the increased use of stereotactic biopsy and interstitial radiotherapy. Complications of therapy seem acceptably low. Five-year survival for benign brain tumor is high, while that for the most common primary tumor, glioblastoma multiforme, is only 5.5%. Some of the findings in this survey confirm those from the literature while others, particularly the pattern of care, represent new data.