D-dimer plasma level: a reliable marker for venous thromboembolism after elective craniotomy

Venous thromboembolism after spontaneous intracerebral hemorrhage and the status quo of anticoagulation in this population: A retrospective casecontrol study from a tertiary hospital in China

OBJECTIVE

Patients with spontaneous intracerebral hemorrhage (sICH) are susceptible to venous thromboembolism (VTE) including pulmonary embolism (PE) and deep venous thrombosis (DVT) due to a variety of risk factors. There are few studies regarding the predictive value of D-dimer for VTE in patients with sICH, and the anticoagulation therapy for these patients are still controversial. The objective of this study is to study the independent predictors of VTE in sICH patients. The rates of anticoagulation therapy and hemorrhagic evens were also investigated.

METHODS

Retrospective review of patients with sICH admitted to the First Affiliated Hospital of Dalian Medical University from 2012 to 2022 and who developed VTE (PE and/or DVT) during hospitalization. A similar number of sICH patients without VTE were randomly selected into the control group. A variety of clinical characteristics were compared between groups. Univariate and multivariate analyses were performed to identify independent predictors of VTE in patients with sICH.

RESULTS

A total of 270 sICH patients were enrolled in this study, including 132 patients with VTE and 138 patients without VTE. After adjusting for other confounders, the maximum level of D-dimer during hospitalization (odds ratio [OR] 1.061, 95 % confidence interval (CI) 1.014-1.110), Glasgow coma scale (GCS) on admission (OR 1.347, 95 % CI 1.110-1.634), modified Rankin Scale (mRS) at discharge (OR 2.578, 95 % CI 1.546-4.298), neutrophil count (OR 1.056, 95 % CI 1.025-1.088) and hospitalization time (OR 1.089, 95 % CI 1.018-1.164) were independently associated with the sICH patients who developed VTE. The maximum D-dimer plasma level of 5.655 mg/L during hospitalization was the optimal threshold to indicate sICH patients developing VTE with a sensitivity of 83.3 % and a specificity of 67.4 %. No patients with sICH received prophylactic anticoagulation therapy against VTE in the present study. A total of 57.6 % (76/132) of the sICH patients with VTE were administered anticoagulant therapy and the rate of hemorrhagic complication was 9.2 %.

CONCLUSIONS

sICH patients with increased levels of D-dimer, higher GCS scores, higher mRS scores, increased neutrophil counts and longer hospitalization time are more likely to develop VTE complications. Routine and serial monitoring of the D-dimer values may be useful in patients with sICH, and VTE should be considered when the plasma level of D-dimer increases to 5.655 mg/L during hospitalization. In tertiary hospitals in China, the rate of sICH patients with VTE receiving anticoagulation treatment is low. Further studies are necessary to explore the safety and efficacy of VTE therapeutic anticoagulation in patients with sICH.

Asymptomatic Postoperative Cerebral Venous Sinus Thrombosis After Posterior Fossa Tumor Surgery: Incidence, Risk Factors, and Therapeutic Options

BACKGROUND

Cerebral venous sinus thrombosis (CVST) is a known complication of posterior fossa surgery near the sigmoid and transverse sinus. The incidence and treatment of postoperative asymptomatic CVST are controversial.

OBJECTIVE

To analyze incidence, risk factors, and management of asymptomatic postoperative CVST after posterior fossa tumor surgery.

METHODS

In this retrospective, single-center study, we included all patients who underwent posterior fossa tumor surgery in the semisitting position between January 2013 and December 2020. All patients underwent preoperative and postoperative imaging using MRI with/without additional computed tomography angiography. We analyzed the effect of demographic and surgical data on the incidence of postoperative CVST. Furthermore, therapeutic anticoagulation or conservative treatment for postoperative CVST and the incidence of intracranial hemorrhage were investigated.

RESULTS

In total, 266 patients were included. Thirty-three of 266 (12.4%) patients developed postoperative CVST. All patients were asymptomatic. Thirteen of 33 patients received therapeutic anticoagulation, and 20 patients did not. Univariate analysis showed that age ( P = .56), sex ( P = .20), American Society of Anesthesiology status ( P = .13), body mass index ( P = .60), and length of surgery ( P = .176) were not statistically correlated with postoperative CVST. Multivariate analysis revealed that meningioma ( P < .001, odds ratio 11.3, CI 95% 4.1-31.2) and vestibular schwannoma ( P = .013, odds ratio 4.4, CI 95% 1.3-16.3) are risk factors for the development of new postoperative CVST. The use of therapeutic anticoagulation to treat postoperative CVST was associated with a higher rate of intracranial hemorrhage (n = 4, P = .017).

CONCLUSION

Tumor entity influences the incidence of postoperative CVST. In clinically asymptomatic patients, careful decision making is necessary whether to initiate therapeutic anticoagulation or not.

Perioperative Deep Vein Thrombosis and D-dimer Measurement in Patients with Brain Tumor

We investigated the appropriate D-dimer cutoff value for each brain tumor type for acute or subacute deep vein thrombosis (DVT) following transcranial brain tumor surgery.In this single-center retrospective study, a cumulative total of 128 patients who underwent transcranial brain tumor surgery were enrolled and classified into the glioma group, the other intracranial malignant tumor group, and the intracranial benign tumor group. Venous ultrasonography was performed if the D-dimer plasma levels were positive (≥1 μg/mL) before surgery and on postoperative day (POD) 3 or 7.Of the 128 cases, DVT developed in 32 (25.0%). Among those, acute or subacute DVT was diagnosed in 22 cases on POD 3 and in 8 cases on POD 7. Compared with DVT-negative cases on POD 3, acute or subacute DVT-positive cases on POD 3 revealed a significant increase in the D-dimer level in all groups combined and in the benign tumor group but not in the glioma group. With regard to DVT on POD 3 in all groups, the receiver operating characteristic curve for the D-dimer level on POD 3 demonstrated a cutoff value of 3.3 μg/mL (sensitivity [0.636] and specificity [0.750]). However, if this cutoff value was used in practice, eight cases would be false-negative with a minimum D-dimer level of 1.5 μg/mL.The D-dimer cutoff value for acute or subacute DVT on POD 3 could be set to 3.3 μg/mL; however, the setting resulted in several false-negative cases. Practically, 1.5 μg/mL of the D-dimer cutoff value on POD 3 might be appropriate to avoid false-negative results.

Prognostic Nomogram for Predicting Lower Extremity Deep Venous Thrombosis in Neurointensive Care Unit Patients: A Prospective Observational Study

Background

Deep venous thrombosis (DVT) of the lower extremities is one of the common complications for neurointensive care unit patients, which leads to increased morbidity and mortality. The purpose of our study was to explore risk factors and develop a prognostic nomogram for lower extremity DVT in neurointensive care unit patients.

Methods

We prospectively collected and analyzed the clinical data of 420 neurointensive care unit patients who received treatment in our institution between January 2018 and September 2019. Stepwise logistic regression was used to select predictors. R software was used to develop the prognostic nomogram. The performance of the nomogram was validated using a validation cohort of patients with data collected between October 2019 and March 2020.

Results

Among 420 patients, 153 (36.4%) had lower extremity DVT and five (1.2%) had both DVT and pulmonary embolism (PE) in our study. Logistic regression analysis indicated that age [odds ratio (OR): 1.050; 95% confidence interval (CI): 1.029–1.071; P < 0.001], Glasgow Coma Scale (GCS) score (OR: 0.889; 95% CI: 0.825–0.959; P = 0.002), D-dimer level (OR: 1.040; 95% CI: 1.008–1.074; P = 0.014), muscle strength (OR: 2.424; 95% CI: 1.346–4.366; P = 0.003), and infection (OR: 1.778; 95% CI: 1.034–3.055; P = 0.037) were independent predictors for lower extremity DVT. These predictors were selected to be included in the nomogram model. The area under the curve values in the primary cohort and validation cohort were 0.817 (95% CI: 0.776–0.858) and 0.778 (95% CI: 0.688–0.868), respectively, and respective Brier scores were 0.167 and 0.183.

Conclusion

Age, GCS score, D-dimer level, muscle strength, and infection are independent predictors for lower extremity DVT. The nomogram is a reliable and convenient model to predict the development of lower extremity DVT in neurointensive care unit patients.

Optimal timing of post-operative enoxaparin after neurosurgery: A single institution experience

PURPOSE

Venous thromboembolism (VTE) is a well-known problem in patients with intracranial tumors, especially high-grade gliomas. Optimal management of VTE complications is critical given that the development of deep vein thrombosis (DVT) and/or pulmonary embolism can exacerbate medical comorbidities and increase mortality. However, little is known about the optimum time to initiate post-operative anticoagulant prophylaxis. Therefore, there is a keen interest amongst neurosurgeons to develop evidence-based protocols to prevent VTE in post-operative brain tumor patients.

METHODS

We retrospectively identified adult patients who underwent elective craniotomy for intracranial tumor resection between 2012 and 2017. Patients were categorized according to the time at which they began receiving prophylactic enoxaparin in the immediate post-operative period, within one day (POD 1), two days (POD 2), three days (POD 3), five days (POD 5), or seven days (POD 7).

RESULTS

A total of 1087 patients had a craniotomy for intracranial tumor resection between 2012 and 2017. Multivariate binomial logistic regression analysis demonstrated that initiation of prophylactic enoxaparin within 72 h of surgery was protective against the likelihood of developing a lower extremity DVT (OR: 0.32; CI: 0.10-0.95; p = 0.049) while controlling for possible risk factors for DVTs identified on univariate analysis. Furthermore, complication rates between the anticoagulation and non-anticoagulation groups were not statistically significant.

CONCLUSION

Initiating anticoagulant prophylaxis with subcutaneous enoxaparin sodium 40 mg once per day within 72 h of surgery can be done safely while reducing the risk of developing lower extremity DVT.

Comparison of the Safety of Prophylactic Anticoagulants After Intracranial Surgery

BACKGROUND

Venous thromboembolism (VTE) represents a rare but preventable postoperative complication. Unfractionated heparin (UH) and low-molecular-weight heparin (LMWH) are used to prevent VTE, but comparative studies of their safety and efficacy in the neurosurgical context are limited.

OBJECTIVE

To determine the relative safety and efficacy of UH and LMWH for prophylaxis after cranial surgery.

METHODS

We performed a retrospective analysis of 3204 elective intracranial surgical admissions in 2901 patients over the period 2013 to 2018. From chart review, we extracted demographic and clinical features, including diagnosis and procedure, drugs administered, and the occurrence of VTE events. To compare postoperative outcomes, we performed propensity score matching of patients receiving different drugs, and reviewed postoperative cranial imaging. To contextualize our results, we selected 14 prior neurosurgical studies of VTE prophylaxis to compare our outcomes to the existing literature.

RESULTS

In our sample of 3204 admissions, the overall rate of VTE was 0.8% (n = 27). Rates of VTE were not statistically different in matched cohorts receiving UH and LMWH (1.7% vs 1.0%, respectively); however, LMWH was associated with a higher rate of clinically significant intracranial hemorrhage (ICH) (3.4% vs 0.5%, P = .008). Literature review and meta-analysis supported these findings. Across studies, UH and LMWH were associated with similar rates of VTE. Studies in which patients received LMWH reported significantly higher rates of ICH (4.9% higher, P = .005).

CONCLUSION

We find that LMWH and UH show similar efficacy in preventing VTE; however, LMWH is associated with higher rates of ICH.

Risk Factors and Clinical Significance of D-Dimer in the Development of Postoperative Venous Thrombosis in Patients with Lung Tumor

BACKGROUND

The incidence of venous thromboembolism (VTE) is higher in patients with lung cancer. The aim of this study was to investigate the risk factors associated with postoperative VTE and explore the VTE predication capacity of D-dimer kinetics.

PATIENTS AND METHODS

Six hundred patients who had lung tumor surgery were analyzed retrospectively between January 2018 and August 2019, and venous ultrasound imaging and D-dimer examination before and after surgery were recommended to all operative patients. Of these 600 patients, 523 patients had venous thromboembolism after surgery, and 77 patients had not found. The general clinical data, postoperative prophylactic anticoagulant therapy, early systemic thromboprophylaxis, 50% increment of D-dimer, 100% increment of D-dimer, and perioperative (preoperative and days 1, 3, and 5 after surgery) D-dimer levels were collected. Logistic regression analysis was used to analyze the independent risk factors of postoperative VTE.

RESULTS

VTE developed in 77 (12.8%) patients. In a univariate analysis, age, surgical approach, tumor size, histology, postoperative preventive anticoagulation, postoperative limb compression therapy, postoperative hemostasis, duration of operation, early systemic thromboprophylaxis, 100% increment of D-dimer, preoperative and postoperative D-dimer level, intraoperative blood loss, and time spent in the hospital were significantly different between the thrombus group and nonthrombus group (P < 0.05). Multivariate analysis showed that age >60 years (P = 0.006) and D-dimer level on 5 days after surgery (P = 0.000) were significant independent risk factors for VTE. Postoperative D-dimer was significantly higher than the preoperative level (P < 0.001). Postoperative D-dimer level was significantly different between benign and malignant tumor groups (P < 0.05) and between the thrombus group and nonthrombus group (P < 0.001). Preventive anticoagulation and limb compression therapy starting from the first day after surgery was statistically significant between the thrombus group and the nonthrombus group (P < 0.05).

CONCLUSION

Continuous detection of D-dimer level after pulmonary tumor surgery combined with thrombotic-related risk factors can better evaluate the occurrence of VTE. Preventive anticoagulant therapy and limb compression therapy starting from the first day after surgery can effectively reduce the incidence of VTE.

Deep Vein Thrombosis and the Neurosurgical Patient

Background

Neurosurgical patients are varied, encompassing cranial and spinal diseases and trauma, and are admitted under both elective and emergency settings. In all settings, neurosurgery patients are at risk of deep vein thrombosis. D-dimer and ultrasound Doppler have long been good screening and confirmatory tools for the diagnosis of deep vein thrombosis (DVT). We conducted a study to identify the factors associated with DVT among neurosurgical patients, and the overall rate of occurrence at our centre. We aimed to also compare our results to the incidence in similar studies elsewhere in which more judicious use of pharmacological prophylaxis was undertaken. We also included the Well’s score to validate its usefulness in screening for DVT in our local setting.

Methods

All patients admitted into our centre were screened for eligibility and those who underwent surgery from September 2016 to September 2017 had a D-dimer screening after surgery, followed by an ultrasound Doppler if the former was positive. The choice of anticoagulant therapy was not influenced by this study, and observation of the use was in keeping with usual practices in our centre was done.

Results

A total number of 331 patients were recruited in this study, however, after the inclusion and exclusion criteria had been met, 320 patients remained eligible, i.e. suitable for analysis. The mean age of our patients was 46 years, with 66% being male patients. A majority of the cases in this study were cranial related, with only 5% being spine surgeries. On the multivariate analysis, the Well’s score and the number of days in bed remained statistically significant, after adjusting for age group, gender, ethnicity, type of central venous access and type of DVT prophylaxis with an adjusted odd’s ratio, and a confidence interval of 95%, and P < 0.05 for each.

Conclusion

Well’s scoring and number of days in bed were independent factors affecting the rate of DVT in patients undergoing neurosurgical procedures in our centre.

Venous thromboembolic events in patients undergoing craniotomy for tumor resection: incidence, predictors, and review of literature

OBJECTIVE

The authors sought to investigate the incidence and predictors of venous thromboembolic events (VTEs) after craniotomy for tumor resection, which are not well established, and the efficacy of and risks associated with VTE chemoprophylaxis, which remains controversial.

METHODS

The authors investigated the incidence of VTEs in a consecutive series of patients presenting to the authors' institution for resection of an intracranial lesion between 2012 and 2017. Information on patient and tumor characteristics was collected and independent predictors of VTEs were determined using stepwise multivariate logistic regression analysis. Review of the literature was performed by searching MEDLINE using the keywords "venous thromboembolism," "deep venous thrombosis," "pulmonary embolism," "craniotomy," and "brain neoplasms."

RESULTS

There were 1622 patients included for analysis. A small majority of patients were female (52.6%) and the mean age of the cohort was 52.9 years (SD 15.8 years). A majority of intracranial lesions were intraaxial (59.3%). The incidence of VTEs was 3.0% and the rates of deep venous thromboses and pulmonary emboli were 2.3% and 0.9%, respectively. On multivariate analysis, increasing patient age (unit OR 1.02, 95% CI 1.00-1.05; p = 0.018), history of VTE (OR 7.26, 95% CI 3.24-16.27; p < 0.001), presence of motor deficit (OR 2.64, 95% CI 1.43-4.88; p = 0.002), postoperative intracranial hemorrhage (OR 4.35, 95% CI 1.51-12.55; p < 0.001), and prolonged intubation or reintubation (OR 3.27, 95% CI 1.28-8.32; p < 0.001) were independently associated with increased odds of a VTE. There were 192 patients who received VTE chemoprophylaxis (11.8%); the mean postoperative day of chemoprophylaxis initiation was 4.6 (SD 3.8). The incidence of VTEs was higher in patients receiving chemoprophylaxis than in patients not receiving chemoprophylaxis (8.3% vs 2.2%; p < 0.001). There were 30 instances of clinically significant postoperative hemorrhage (1.9%), with only 1 hemorrhage occurring after initiation of VTE chemoprophylaxis (0.1%).

CONCLUSIONS

The study results show the incidence and predictors of VTEs after craniotomy for tumor resection in this patient population. The incidence of VTE within this cohort appears low and comparable to that observed in other institutional series, despite the lack of routine prophylactic anticoagulation in the postoperative setting.

Administration routes affect thrombolytic effect of catheter-directed thrombolysis with pro-urokinase in treating deep vein thrombosis

Background

Deep venous thrombosis (DVT) is a common disorder with a significant mortality rate. Catheter-directed thrombolysis (CDT) is a preferred treatment for DVT patients. The aim of this study is to evaluate the thrombolytic effect of CDT with pro-urokinase (pro-UK) in different administration routes.

Methods

An inferior vena cava (IVC) model was induced in 36 New Zealand white rabbits by catheter injury and placement of IVC filter. The animals were divided into 6 groups with 6 rabbits in each group: group A: systemic thrombolysis with intravenous injection; group B: CDT with pump infusion; group C: CDT with pulse injection; group D: CDT with combination of pump infusion and pulse injection; group E: catheter-directed aspiration thrombectomy; group F: mechanical thrombectomy. The thrombolytic effects were evaluated by color Doppler ultrasound and blood measurement of D-dimer and fibrinogen.

Results

The minimum effective concentration of pro-UK solution was identified. Two groups (group A and B) did not achieve successful thrombolysis. Among all catheter-directed administration groups, the rabbit groups that received pro-UK therapy through catheter-directed thrombolytic pump infusion combined with pulse injection (group D) showed the best thrombolysis effect. In contrast, catheter-directed aspiration thrombectomy (group E) is effective but not safe.

Conclusions

CDT with combination of pump infusion and pulse injection of pro-UK safely and significantly improves thrombolysis procedure in rabbits, suggesting potential benefits from the use of CDT in proximal DVT.

Reduced risk of venous thromboembolism with the use of intermittent pneumatic compression after craniotomy: a randomized controlled prospective study

OBJECTIVE

The term "venous thromboembolism" (VTE) subsumes deep venous thrombosis (DVT) and pulmonary embolism. The incidence of DVT after craniotomy was reported to be as high as 50%. Even clinically silent DVT may lead to potentially fatal pulmonary embolism. The risk of VTE is correlated with duration of surgery, and it appears likely that it develops during surgery. The present study aimed to evaluate intraoperative use of intermittent pneumatic compression (IPC) of the lower extremity for prevention of VTE in patients undergoing craniotomy.

METHODS

A total of 108 patients undergoing elective craniotomy for intracranial pathology were included in a single-center controlled randomized prospective study. In the control group, conventional compression stockings were worn during surgery. In the treatment group, IPC of the calves was used in addition. The presence of DVT was evaluated by Doppler sonography pre- and postoperatively.

RESULTS

Intraoperative use of IPC led to a significant reduction of VTE (p = 0.029). In logistic regression analysis, the risk of VTE was approximately quartered by the use of IPC. Duration of surgery was confirmed to be correlated with VTE incidence (p < 0.01); every hour of surgery increased the risk by a factor of 1.56.

CONCLUSIONS

Intraoperative use of IPC significantly lowers the incidence of potentially fatal VTE in patients undergoing craniotomy. The method is easy to use and carries no additional risks.■ CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: randomized controlled trial; evidence: class I.Clinical trial registration no.: DRKS00011783 (https://www.drks.de).

Risk factors governing the development of cerebral vein and dural sinus thrombosis after craniotomy in patients with intracranial tumors

OBJECTIVE

Neurosurgical intervention may increase the risk of developing cerebral vein and dural sinus thrombosis (CVT). The clinical management of CVT in postoperative patients remains unclear. This retrospective study explores the disease occurrence, associated risk factors, and outcomes in patients with tumors who developed CVT after craniotomy.

METHODS

A retrospective analysis and review of patient records in those who had undergone cranial tumor removal within the authors' neurosurgical department was performed. In so doing, the authors identified a cohort of patients who developed CVT postoperatively. The study included patients who presented to the department between January 2004 and December 2013.

RESULTS

Of 2286 patients with intracranial lesions who underwent craniotomy, 35 (1.5%) went on to develop CVT. The authors identified the semisitting position (OR 7.55, 95% CI 3.73–15.31, p < 0.001); intraoperative sinus injury (OR 1.5, 95% CI 3.57–15.76, p < 0.001); and known CVT risk factors (OR 7.77, 95% CI 2.28–21.39, p < 0.001) as predictors of CVT development. Of note, 19 patients (54.3%) had good outcomes (modified Rankin Scale Score 0–1), whereas 9 patients (25.7%) had suffered dependency or death (modified Rankin Scale Score 4–6) at last follow-up. Intracerebral hemorrhage (OR 21.27, 95% CI 1.59–285.01, p = 0.02) and delayed delivery of an intermediate dose of low-molecular-weight heparin anticoagulation (OR 24.12, 95% CI 2.08–280.13, p = 0.01) were associated with unfavorable outcomes.

CONCLUSIONS

Only a minority of patients undergoing craniotomy for tumor removal develop CVT, and the majority of those who do develop CVT recover well. Early administration of an intermediate dose of low-molecular-weight heparin anticoagulation might be considered once CVT is diagnosed.

Safety of fondaparinux for prevention of postoperative venous thromboembolism in urological malignancy: A prospective randomized clinical trial

OBJECTIVES

To prospectively evaluate the safety of postoperative fondaparinux in comparison with low molecular weight heparin in patients undergoing uro-oncological surgery.

METHODS

The present study was a prospective, single-blind, non-inferiority randomized trial. A total of 359 patients undergoing surgery for urological malignancy were enrolled from January 2011 to December 2012. A total of 298 of these patients (fondaparinux group, 152; low molecular weight heparin group, 146) were evaluable for the intention-to-treat-analysis. Patients were randomly assigned to low-dose unfractionated heparin, 5000 units twice daily until postoperative day 1 plus either fondaparinux 2.5 mg once daily or low molecular weight heparin 2000 units twice daily until postoperative day 5. The primary end-point was postoperative bleeding as by independent review, and the study was powered to show the non-inferiority of fondaparinux versus low molecular weight heparin. The other adverse events were evaluated. D-dimer and soluble fibrin monomer complex levels were measured perioperatively.

RESULTS

Bleeding occurred in 21 patients (12 in the fondaparinux group and 9 in low molecular weight heparin group, respectively). No significant differences were detected in the incidence of postoperative bleeding and the other adverse events between the two groups. The D-dimer was elevated on postoperative day 1 in one patient (16.6 μg/mL). In another patient, the soluble fibrin monomer complex was elevated (109 μg/mL).

CONCLUSIONS

Fondaparinux is non-inferior to low molecular weight heparin with respect to risk of bleeding. The favorable safety profile of fondparinux supports its prophylactic use as an alternative to low molecular weight heparin after surgery for urological malignancy.

Role of Physical Therapists in the Management of Individuals at Risk for or Diagnosed With Venous Thromboembolism: Evidence-Based Clinical Practice Guideline

The American Physical Therapy Association (APTA), in conjunction with the Cardiovascular & Pulmonary and Acute Care sections of APTA, have developed this clinical practice guideline to assist physical therapists in their decision-making process when treating patients at risk for venous thromboembolism (VTE) or diagnosed with a lower extremity deep vein thrombosis (LE DVT). No matter the practice setting, physical therapists work with patients who are at risk for or have a history of VTE. This document will guide physical therapist practice in the prevention of, screening for, and treatment of patients at risk for or diagnosed with LE DVT. Through a systematic review of published studies and a structured appraisal process, key action statements were written to guide the physical therapist. The evidence supporting each action was rated, and the strength of statement was determined. Clinical practice algorithms, based on the key action statements, were developed that can assist with clinical decision making. Physical therapists, along with other members of the health care team, should work to implement these key action statements to decrease the incidence of VTE, improve the diagnosis and acute management of LE DVT, and reduce the long-term complications of LE DVT.

Clinical features and risk factor analysis for lower extremity deep venous thrombosis in Chinese neurosurgical patients

Background:

Deep venous thrombosis (DVT) contributes significantly to the morbidity and mortality of neurosurgical patients; however, no data regarding lower extremity DVT in postoperative Chinese neurosurgical patients have been reported.

Materials and Methods:

From January 2012 to December 2013, 196 patients without preoperative DVT who underwent neurosurgical operations were evaluated by color Doppler ultrasonography and D-dimer level measurements on the 3^rd, 7^th, and 14^th days after surgery. Follow-up clinical data were recorded to determine the incidence of lower extremity DVT in postoperative neurosurgical patients and to analyze related clinical features. First, a single factor analysis, Chi-square test, was used to select statistically significant factors. Then, a multivariate analysis, binary logistic regression analysis, was used to determine risk factors for lower extremity DVT in postoperative neurosurgical patients.

Results:

Lower extremity DVT occurred in 61 patients, and the incidence of DVT was 31.1% in the enrolled Chinese neurosurgical patients. The common symptoms of DVT were limb swelling and lower extremity pain as well as increased soft tissue tension. The common sites of venous involvement were the calf muscle and peroneal and posterior tibial veins. The single factor analysis showed statistically significant differences in DVT risk factors, including age, hypertension, smoking status, operation time, a bedridden or paralyzed state, the presence of a tumor, postoperative dehydration, and glucocorticoid treatment, between the two groups (P < 0.05). The binary logistic regression analysis showed that an age greater than 50 years, hypertension, a bedridden or paralyzed state, the presence of a tumor, and postoperative dehydration were risk factors for lower extremity DVT in postoperative neurosurgical patients.

Conclusions:

Lower extremity DVT was a common complication following craniotomy in the enrolled Chinese neurosurgical patients. Multiple factors were identified as predictive of DVT in neurosurgical patients, including the presence of a tumor, an age greater than 50 years, hypertension, and immobility.

Diagnostic Value of Elevated D-Dimer Level in Venous Thromboembolism in Patients With Acute or Subacute Brain Lesions

Objective

To define the risk factors that influence the occurrence of venous thromboembolism (VTE) in patients with acute or subacute brain lesions and to determine the usefulness of D-dimer levels for VTE screening of these patients.

Methods

Medical data from January 2012 to December 2013 were retrospectively reviewed. Mean D-dimer levels in those with VTE versus those without VTE were compared. Factors associated with VTE were analyzed and the odds ratios (ORs) were calculated. The D-dimer cutoff value for patients with hemiplegia was defined using a receiver operating characteristic (ROC) curve.

Results

Of 117 patients with acute or subacute brain lesions, 65 patients with elevated D-dimer levels (mean, 5.1±5.8 mg/L; positive result >0.55 mg/L) were identified. Logistic regression analysis showed that the risk of VTE was 3.9 times higher in those with urinary tract infections (UTIs) (p=0.0255). The risk of VTE was 4.5 times higher in those who had recently undergone surgery (p=0.0151). Analysis of the ROC showed 3.95 mg/L to be the appropriate D-dimer cutoff value for screening for VTE (area under the curve [AUC], 0.63; 95% confidence interval [CI], 0.5-0.8) in patients with acute or subacute brain lesions. This differs greatly from the conventional D-dimer cutoff value of 0.55 mg/L. D-dimer levels less than 3.95 mg/L in the absence of surgery showed a negative predictive value of 95.8% (95% CI, 78.8-99.8).

Conclusion

Elevated D-dimer levels alone have some value in VTE diagnosis. However, the concomitant presence of UTI or a history of recent surgery significantly increased the risk of VTE in patients with acute or subacute brain lesions. Therefore, a different D-dimer cutoff value should be applied in these cases.

A prospective multicenter study of venous thromboembolism in patients with newly-diagnosed high-grade glioma: hazard rate and risk factors

Venous thromboembolism (VTE) is a common complication in patients with high-grade gliomas. The purpose of this prospective multicenter study was to determine the hazard rate of first symptomatic VTE in newly-diagnosed glioma patients and identify clinical and laboratory risk factors. On enrollment, demographic and clinical information were recorded and a comprehensive coagulation evaluation was performed. Patients were followed until death. The study end point was objectively-documented symptomatic VTE. One hundred seven patients were enrolled with a median age of 57 years (range 29-85) between June 2005 and April 2008. Ninety-one (85 %) had glioblastoma multiforme (GBM). During an average survival of 17.7 months, 26 patients (24 %) (95 % CI 17-34 %) developed VTE (hazard rate 0.15 per person-year) and 94 patients (88 %) died. Median time to VTE was 14.2 weeks post-operation (range 3-126). Patients with an initial tumor biopsy were 3.0 fold more likely to suffer VTE (p = 0.02). Patients with an elevated factor VIII activity (>147 %) were 2.1-fold more likely to develop VTE. ABO blood group, D dimer and thrombin generation were not associated with VTE. No fatal VTE occurred. VTE is a common complication in patients with newly-diagnosed high grade gliomas, particularly in the first six months after diagnosis. Patients with an initial tumor biopsy and elevated factor VIII levels are at increased risk. However, VTE was not judged to be primarily responsible for any patient deaths. Therefore, outpatient primary VTE prophylaxis remains investigational until more effective primary prophylaxis strategies and therapies for glioma are identified.

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.