Deep vein thrombophlebitis and pulmonary embolism in patients with malignant gliomas

Risk of Deep vein thrombosis in neurosurgery: State of the art on prophylaxis protocols and best clinical practices

OBJECTIVE

To analytically discuss some protocols in Deep vein thrombosis (DVT)/pulmonary Embolism (PE) prophylaxis currently use in Neurosurgical Departments around the world.

DATA SOURCES

Analysis of the prophylaxis protocols in the English literature: An analytical and narrative review of literature concerning DVT prophylaxis protocols in Neurosurgery have been conducted by a PubMed search (back to 1978).

DATA EXTRACTION

80 abstracts were reviewed, and 74 articles were extracted.

DATA ANALYSIS

The majority of DVT seems to develop within the first week after a neurosurgical procedure, and a linear correlation between the duration of surgery and DVT occurrence has been highlighted. The incidence of DVT seems greater for cranial (7.7%) than spinal procedures (1.5%). Although intermittent pneumatic compression (IPC) devices provided adequate reduction of DVT/PE in some cranial and combined cranial/spinal series, low-dose subcutaneous unfractionated heparin (UFH) or low molecular-weight heparin (LMWH) further reduced the incidence, not always of DVT, but of PE. Nevertheless, low-dose heparin-based prophylaxis in cranial and spinal series risks minor and major postoperative haemorrhages: 2-4% in cranial series, 3.4% minor and 3.4% major haemorrhages in combined cranial/spinal series, and a 0.7% incidence of major/minor haemorrhages in spinal series.

CONCLUSION

This analysis showed that currently most of the articles are represented by case series and case reports. As long as clear guidelines will not be defined and universally applied to this diverse group of patients, any prophylaxis for DVT and PE should be tailored to the individual patient with cautious assessment of benefits versus risks.

Venous Thromboembolism and Malignant Brain Tumors: A Review

The incidence of venous thromboembolism (VTE) in patients with primary brain tumors varies be tween 1 and 60%. This variability in incidence is due to study differences in (a) methods of diagnosis of VTE— i.e., diagnosis at autopsy or clinical diagnosis; (b) amount of time from surgery to VTE diagnosis; (c) proportion of patients receiving deep venous thrombosis (DVT) pro phylaxis ; (d) clinical risk factors associated with VTE, such as paresis, prior thrombotic disease, and chemother apy; and (e) tumor location and histology. The etiology of VTE in patients with primary brain tumors is unknown. The preoperative hemostatic abnormalities noted in clin ical studies have been most consistent with compensated disseminated intravascular coagulation (DIC). These ab normalities, however, appear to be of little predictive value for the subsequent development of VTE. Studies involving brain tumor tissue or cell cultures have impli cated factors released by the tumor or surrounding neural tissue that activate the coagulation system or inhibit fi brinolysis. Recommendations for VTE prophylaxis in clude (a) earliest possible ambulation; (b) intermittent pneumatic compression in all nonambulatory patients preoperatively and postoperatively; and (c) s.c. heparin in high-risk patients. The role of low-molecular-weight heparin in VTE prophylaxis has not been established. Patients with malignant brain tumors can be safely anti coagulated with heparin and warfarin if these agents are carefully monitored. Of 197 patients in seven series who received anticoagulants, only 5 (2.5%) had intracranial bleeding. Vena caval filters and thrombectomy are rarely required. Thrombolytic therapy is contraindicated. Key Words: Venous thromboembolism—Deep venous throm bosis—Malignant brain tumors.

Vena Caval Filters: A Review for Intensive Care Specialists

Venous thromboembolism (VTE) is a common complication among patients in the intensive care unit. While anticoagulation remains standard therapy, vena caval filters are an important alternative when anticoagulation is contraindicated. To determine the safety and efficacy of vena caval filters in the treatment of VTE, a comprehensive review of the English-language medical literature was performed. Except for one randomized controlled trial, the literature supporting the use of vena caval filters consists almost exclusively of case series, which in many instances are limited by incomplete and short follow-up. While case series suggest that filters function effectively in the prevention of pulmonary embolism (2%-4% symptomatic pulmonary embolism [PE], fatal PE < 2%), recent higher quality studies indicate that filters may not provide significant additional protection to that provided by anticoagulation alone. Furthermore, filters are associated with a 2- fold increase in the incidence of recurrent DVT. Until randomized comparative studies are available, the safety and efficacy of all the available devices should be considered to be roughly equivalent. Since filters do not inhibit continued clot formation, all filter patients should receive anticoagulation for durations appropriate for their thrombotic disorder. Although extended anticoagulation may prevent thrombotic complications associated with filter placement, this strategy has yet to be experimentally tested. While many additional indications for vena caval filter use have been proposed (VTE in cancer patients, PE prophylaxis in trauma patients, etc), well-designed clinical trials demonstrating their efficacy in these situations are lacking. Further development of temporary/retrievable filters, which offer the potential to avoid the long-term complications of permanent filters, should be a research priority. Until additional data are available, vena caval filters should generally be restricted to patients with VTE who cannot receive anticoagulation.

Clinical factors associated with venous thromboembolism risk in patients undergoing craniotomy

OBJECT

Patients undergoing craniotomy are at risk for developing venous thromboembolism (VTE). The safety of anticoagulation in these patients is not clear. The authors sought to identify risk factors predictive of VTE in patients undergoing craniotomy.

METHODS

The authors reviewed a national surgical quality database, the American College of Surgeons National Surgical Quality Improvement Program. Craniotomy patients were identified by current procedural terminology code. Clinical factors were analyzed to identify associations with VTE.

RESULTS

Four thousand eight hundred forty-four adult patients who underwent craniotomy were identified. The rate of VTE in the cohort was 3.5%, including pulmonary embolism in 1.4% and deep venous thrombosis in 2.6%. A number of factors were found to be statistically significant in multivariate binary logistic regression analysis, including craniotomy for tumor, transfer from acute care hospital, age ≥ 60 years, dependent functional status, tumor involving the CNS, sepsis, emergency surgery, surgery time ≥ 4 hours, postoperative urinary tract infection, postoperative pneumonia, on ventilator ≥ 48 hours postoperatively, and return to the operating room. Patients were assigned a score based on how many of these factors they had (minimum score 0, maximum score 12). Increasing score was predictive of increased VTE incidence, as well as risk of mortality, and time from surgery to discharge.

CONCLUSIONS

Patients undergoing craniotomy are at low risk of developing VTE, but this risk is increased by preoperative medical comorbidities and postoperative complications. The presence of more of these clinical factors is associated with progressively increased VTE risk; patients possessing a VTE Risk Score of ≥ 5 had a greater than 20-fold increased risk of VTE compared with patients with a VTE score of 0.

Subcutaneous heparin for prophylaxis of venous thromboembolism in deep brain stimulation surgery: evidence from a decision analysis

OBJECTIVE

The addition of subcutaneous heparin (SQH) to mechanical prophylaxis for venous thromboembolism (VTE) involves a balance between the benefit of greater protection from VTE and the added risk of intracranial hemorrhage. There is evidence that the hemorrhage risk outweighs the benefits for patients undergoing craniotomy. We investigated the safety of SQH in patients undergoing deep brain stimulation (DBS) surgery.

METHODS

A retrospective analysis was performed of all patients with movement disorders (n = 254) undergoing DBS surgery at our institution from 2003 to 2007. Before September 2005, none of the patients undergoing DBS received SQH (non-SQH group) (n = 121). Thereafter, all patients were administered SQH perioperatively (SQH group) (n = 133). All patients wore graduated compression stockings and pneumatic compression boots postoperatively in bed. A postoperative brain magnetic resonance imaging scan was obtained on the day of surgery.

RESULTS

Five (3.8%) of 133 SQH patients and 1 (0.8%) of 121 non-SQH patients developed asymptomatic intracranial hemorrhage. None of the SQH patients developed clinically significant VTE, whereas 3 (2.5%) non-SQH patients developed VTE (1 deep venous thrombosis, 2 pulmonary embolisms). Using a decision-analysis model, we have shown that the use of SQH plus mechanical prophylaxis together yielded outcomes at least as good as mechanical prophylaxis alone.

CONCLUSION

Our findings suggest that SQH for VTE prophylaxis in patients with movement disorders undergoing DBS surgery is safe. SQH protects against VTE in this patient population and merits further investigation.

Management of venous thromboembolism in patients with primary and metastatic brain tumors

Venous thromboembolism occurs commonly throughout the clinical course of patients with brain tumors. A number of hemostatic and clinical factors contribute to this hypercoagulable state. Concern over the possibility of intracranial bleeding has limited the use of anticoagulation in this population. However, mechanical approaches such as vena cava filters have high complication and treatment failure rates in patients with intracranial malignancies. In addition, the available data suggest that anticoagulation can be used safely and effectively in most of these patients. Patients with thrombocytopenia, recent neurosurgery, and tumor types prone to bleeding require special consideration. When intracranial hemorrhage does occur, it is often due to overanticoagulation, requiring prompt anticoagulation reversal and neurosurgical consultation.

Prophylaxis for deep venous thrombosis in patients with craniotomies: a review

Deep venous thrombosis (DVT) remains a source of significant morbidity and mortality in patients who undergo craniotomy procedures. Despite several studies in which the safety and efficacy of various prophylactic strategies were examined, there is still no consensus among clinicians. In this paper the authors review the literature with regard to epidemiological and pathophysiological features, screening methods, and prophylactic measures for DVT.

The risk of venous thromboembolism is increased throughout the course of malignant glioma: an evidence-based review

BACKGROUND

Venous thromboembolism (VTE) frequently complicates the course of patients with cancer, and there is evidence to suggest that patients with brain tumors are at particularly high risk. The objective of this methodology-based literature review was to quantify the rate of incidence of VTE in patients with malignant glioma and to determine the factors that predict an increased risk of this complication.

METHODS

Studies meeting predefined inclusion criteria were evaluated independently on an eight-item methodology index by three raters. Authors were contacted to resolve ambiguities. The results of the studies were summarized and the incidence rate of VTE within the early postoperative phase and during extended follow-up were reported separately.

RESULTS

Within 6 weeks after surgery the incidence rate of deep venous thrombosis (DVT) ranged from 3% to 60%, varying with the prophylaxis regimen used, the method of diagnosis, and the study design. Beyond 6 weeks postoperatively, the rates of DVT ranged from 0.013 to 0.023 per patient-month of follow-up. The single study with no significant methodologic deficiencies found a 24% rate of incidence of symptomatic DVT over the 17 months of follow-up beyond the first 6 postoperative weeks. In 6 studies the presence of leg paresis, histologic diagnosis of glioblastoma multiform, age >/= 60 years, large tumor size, use of chemotherapy, and length of surgery > 4 hours were identified as possible risk factors.

CONCLUSIONS

The incidence of VTE is high throughout the course of malignant glioma. A randomized, controlled trial is needed to clarify whether the benefits of long term anticoagulant prophylaxis outweigh the risks and costs of such therapy.

Venous thromboembolism in neurosurgery and neurology patients: a review

Thromboembolism is a common problem in neurosurgery and neurology patients. Within this diverse population are subpopulations of patients with varying degrees of thromboembolic risk: low, moderate, and high. Patients at substantial risk for deep vein thrombosis and pulmonary embolism include those with spinal cord injury, brain tumor, subarachnoid hemorrhage, head trauma, stroke, and patients undergoing a neurosurgical operation. There are prophylactic strategies that can be applied to these various risk groups that will dramatically reduce the incidence of thromboembolism. The risk of pulmonary embolism or fatal pulmonary embolism typically exceeds the risk of severe or fatal bleeding from adequate prophylaxis, and these techniques should be applied on a routine basis. To adequately care for patients with deep venous thrombosis and pulmonary embolism, the physician requires a thorough understanding of the methods of diagnosis, the pharmacokinetics of heparin and warfarin, and a knowledge of their role in the treatment strategies that have proven efficacy and safety. In addition, an awareness of the low molecular weight heparins and heparinoids is becoming essential. These new agents have a potentially promising role in both the prophylaxis and treatment of patients with neurological disease. The principles concerning the prophylaxis, diagnosis, and clinical management of venous thromboembolic disease in neurosurgery and neurology patients are dealt with in this review.

Therapy of venous thromboembolism in patients with brain metastases

BACKGROUND

Deep venous thrombosis (DVT) and pulmonary embolism (PE) are common in patients with brain metastases. Few data exist to help guide the clinician's choice between the two therapeutic options of anticoagulation and inferior vena cava filter placement.

METHODS

The authors reviewed their institutions' experience with the treatment of venous thromboembolism in 51 adult patients with known brain metastases since 1980.

RESULTS

Ten patients were initially treated with Greenfield filters; four (40%) had recurrent nonfatal thromboembolic events (two PE and two DVT), and three required anticoagulation. Thirty-nine patients were treated initially with anticoagulation; none of these patients later received filters. Two patients with DVT were untreated and both died of PE. Among 42 patients who received anticoagulation, the duration of anticoagulation ranged from 5 to 563 days (mean, 100 days). Two patients who received anticoagulation experienced devastating central nervous system hemorrhage in the setting of supratherapeutic anticoagulation by conventional laboratory criteria. A third patient experienced a minor deterioration, possibly attributable to hemorrhage, for a 7% (3 of 42) incidence of serious central nervous system complications. Three asymptomatic patients developed hyperdensity within metastases on routine follow-up noncontrast computed tomography scan, suggesting possible intratumoral hemorrhage. Three patients taking warfarin had recurrent DVT with prothrombin time between 15.1 and 17.7. Systemic bleeding complications were generally minor and occurred in only eight patients (19%).

CONCLUSIONS

Anticoagulation is more effective than Greenfield filters and acceptably safe when maintained in the therapeutic range in most patients with brain metastases and venous thromboembolism.

Prophylaxis of venous thromboembolism in brain tumor patients

Thromboembolism is a common problem in patients with brain tumors. Within this population are subpopulations of patients at varying but substantial risk for deep vein thrombosis and pulmonary embolism. Prophylactic strategies can be applied to these various risk groups that will dramatically reduce the incidence of thromboembolism, and these should be applied on a routine basis. The standard prophylactic methods for thromboembolic prophylaxis include mechanical devices (e.g., graduated leg stockings; external pneumatic calf compression) and pharmacological agents (e.g., low dose heparin). In addition, a basic knowledge of low molecular weight heparins and heparinoids is essential because these new agents have a potentially promising role in the prophylaxis of neurological disease in certain patients. The principles concerning the prophylaxis of venous thromboembolic disease in patients with brain tumors are addressed in this review.

Greenfield filter instead of heparin as primary treatment for deep venous thrombosis or pulmonary embolism in patients with cancer

BACKGROUND AND METHOD

During the last 5 years, the authors placed Greenfield filters as primary therapy in 41 patients with cancer with deep venous thrombosis (DVT) and/or pulmonary embolism (PE) instead of administering heparin.

RESULTS

There were no operative deaths. Complications included erythema of the incision in one patient, recurrent PE in one patient, and chronic filter prong penetration of the inferior vena caval wall in one patient. Follow-up was complete for 90% (37 of 41) of the patients. Forty-six percent of the patients died of their cancer early in the study. In follow-up, leg swelling improved completely or partially in 74.5% of patients and was unchanged in 22% of patients. The condition of one patient worsened secondary to recurrent DVT. The patients with improved symptoms also had improved functional ability, whereas those whose condition did not change were mostly bedridden, many with end-stage advanced metastatic disease.

CONCLUSIONS

These results indicate that Greenfield filter insertion is safe and effective as primary therapy in patients with cancer with DVT and/or PE.