Intermittend pneumatic venous thrombembolism (VTE) prophylaxis during neurosurgical procedures

BACKGROUND

The management of perioperative venous thrombembolism (VTE) prophylaxis is highly variable between neurosurgical departments and general guidelines are missing. The main issue in debate are the dose and initiation time of pharmacologic VTE prevention to balance the risk of VTE-based morbidity and potentially life-threatening bleeding. Mechanical VTE prophylaxis with intermittend pneumatic compression (IPC), however, is established in only a few neurosurgical hospitals, and its efficacy has not yet been demonstrated. The objective of the present study was to analyze the risk of VTE before and after the implementation of IPC devices during elective neurosurgical procedures.

METHODS

All elective surgeries performed at our neurosurgical department between 01/2018-08/2022 were investigated regarding the occurrence of VTE. The VTE risk and associated mortality were compared between groups: (1) only chemoprophylaxis (CHEMO; surgeries 01/2018-04/2020) and (2) IPC and chemoprophylaxis (IPC; surgeries 04/2020-08/2022). Furthermore, general patient and disease characteristics as well as duration of hospitalization were evaluated and compared to the VTE risk.

RESULTS

VTE occurred after 38 elective procedures among > 12.000 surgeries. The number of VTEs significantly differed between groups with an incidence of 31/6663 (0.47%) in the CHEMO group and 7/6688 (0.1%) events in the IPC group. In both groups, patients with malignant brain tumors represented the largest proportion of patients, while VTEs in benign tumors occurred only in the CHEMO group.

CONCLUSION

The use of combined mechanical and pharmacologic VTE prophylaxis can significantly reduce the risk of postoperative thromboembolism after neurosurgical procedures and, therefore, reduce mortality and morbidity.

Pharmacologic Venous Thromboembolism Prophylaxis in Patients with Nontraumatic Subarachnoid Hemorrhage Requiring an External Ventricular Drain

BACKGROUND

Optimal pharmacologic thromboprophylaxis dosing is not well described in patients with subarachnoid hemorrhage (SAH) with an external ventricular drain (EVD). Our patients with SAH with an EVD who receive prophylactic enoxaparin are routinely monitored using timed anti-Xa levels. Our primary study goal was to determine the frequency of venous thromboembolism (VTE) and secondary intracranial hemorrhage (ICH) for this population of patients who received pharmacologic prophylaxis with enoxaparin or unfractionated heparin (UFH).

METHODS

A retrospective chart review was performed for all patients with SAH admitted to the neurocritical care unit at Emory University Hospital between 2012 and 2017. All patients with SAH who required an EVD were included.

RESULTS

Of 1,351 patients screened, 868 required an EVD. Of these 868 patients, 627 received enoxaparin, 114 received UFH, and 127 did not receive pharmacologic prophylaxis. VTE occurred in 7.5% of patients in the enoxaparin group, 4.4% in the UFH group (p = 0.32), and 3.2% in the no VTE prophylaxis group (p = 0.08). Secondary ICH occurred in 3.83% of patients in the enoxaparin group, 3.51% in the UFH group (p = 1), and 3.94% in the no VTE prophylaxis group (p = 0.53). As steady-state anti-Xa levels increased from 0.1 units/mL to > 0.3 units/mL, there was a trend toward a lower incidence of VTE. However, no correlation was noted between rising anti-Xa levels and an increased incidence of secondary ICH. When compared, neither enoxaparin nor UFH use was associated with a significantly reduced incidence of VTE or an increased incidence of ICH.

CONCLUSIONS

In this retrospective study of patients with nontraumatic SAH with an EVD who received enoxaparin or UFH VTE prophylaxis or no VTE prophylaxis, there was no statistically significant difference in the incidence of VTE or secondary ICH. For patients receiving prophylactic enoxaparin, achieving higher steady-state target anti-Xa levels may be associated with a lower incidence of VTE without increasing the risk of secondary ICH.

Chemoprophylactic Anticoagulation After Spine Surgery Does Not Increase Epidural Hematoma Risk: A Propensity-matched Analysis

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To calculate the magnitude of any increased risk of epidural hematoma (EDH) associated with chemoprophylactic anticoagulation (chemoprophylaxis), if any.

SUMMARY OF BACKGROUND DATA

Chemoprophylaxis for the prevention of venous thromboembolic events may be associated with an increased risk of EDH after spine surgery.

MATERIALS AND METHODS

A total of 6869 consecutive spine surgeries performed at our institution were identified, and clinical and demographic data were collected. We identified cases in which symptomatic EDHs were evacuated within 30 days postoperatively. Patients receiving chemoprophylaxis and controls were matched using K-nearest neighbor propensity score matching to calculate the effect of anticoagulation on the rate of postoperative EDH.

RESULTS

After propensity score matching, 1071 patients who received chemoprophylaxis were matched to 1585 controls. Propensity scores were well balanced between populations (Rubin B=20.6, Rubin R=1.05), and an 89.6% reduction in bias was achieved, with a remaining mean bias of 3.2%. The effect of chemoprophylaxis on EDH was insignificant ( P =0.294). Symptomatic EDH was independently associated with having a transfusion [odds ratio (OR)=7.30 (1.15, 46.20), P =0.035], having thoracic-level surgery [OR=41.19 (3.75, 452.4), P =0.002], and increasing body mass index [OR=1.44 (1.04, 1.98), P =0.028] but was not associated with chemoprophylaxis. Five out of 13 patients who developed EDH (38.5%) were receiving some form of anticoagulation, including 1 patient on therapeutic anticoagulation, 1 concurrently on aspirin and chemoprophylaxis, and 2 who were also found to have developed thrombocytopenia postoperatively. The median time on anticoagulation before EDH was 8.1 days. A higher proportion of patients who developed EDH also developed venous thromboembolic events than the general population [38.5% vs. 2.4%, OR=25.34 (9.226, 79.68), P <0.0001], and 1 EDH patient died from pulmonary embolism while off chemoprophylaxis.

CONCLUSIONS

Chemoprophylactic anticoagulation did not cause an increase in the rate of spinal EDH in our patient population.

Development and Validation of a Clinical Prediction Model for Venous Thromboembolism Following Neurosurgery: A 6-Year, Multicenter, Retrospective and Prospective Diagnostic Cohort Study

BACKGROUND

Based on the literature and data on its clinical trials, the incidence of venous thromboembolism (VTE) in patients undergoing neurosurgery has been 3.0%~26%. We used advanced machine learning techniques and statistical methods to provide a clinical prediction model for VTE after neurosurgery.

METHODS

All patients (n = 5867) who underwent neurosurgery from the development and retrospective internal validation cohorts were obtained from May 2017 to April 2022 at the Department of Neurosurgery at the Sanbo Brain Hospital. The clinical and biomarker variables were divided into pre-, intra-, and postoperative. A univariate logistic regression (LR) was applied to explore the 67 candidate predictors with VTE. We used a multivariable logistic regression (MLR) to select all significant MLR variables of MLR to build the clinical risk prediction model. We used a random forest to calculate the importance of significant variables of MLR. In addition, we conducted prospective internal (n = 490) and external validation (n = 2301) for the model.

RESULTS

Eight variables were selected for inclusion in the final clinical prediction model: D-dimer before surgery, activated partial thromboplastin time before neurosurgery, age, craniopharyngioma, duration of operation, disturbance of consciousness on the second day after surgery and high dose of mannitol, and highest D-dimer within 72 h after surgery. The area under the curve (AUC) values for the development, retrospective internal validation, and prospective internal validation cohorts were 0.78, 0.77, and 0.79, respectively. The external validation set had the highest AUC value of 0.85.

CONCLUSIONS

This validated clinical prediction model, including eight clinical factors and biomarkers, predicted the risk of VTE following neurosurgery. Looking forward to further research exploring the standardization of clinical decision-making for primary VTE prevention based on this model.

Venous thromboembolism in aneurysmal subarachnoid hemorrhage: Risk factors and timing of chemoprophylaxis

INTRODUCTION

Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality among patients recovering from aneurysmal subarachnoid hemorrhage (aSAH). Prophylactic heparin reduces the risk of VTE, but the optimal timing for its initiation among aSAH patients remains unclear.

OBJECTIVE

To conduct a retrospective study assessing risk factors for VTE and optimal timing of chemoprophylaxis in patients treated for aSAH.

METHODS

From 2016-2020, 194 adult patients were treated for aSAH at our institution. Patient demographics, clinical diagnoses, complications, pharmacologic interventions, and outcomes were recorded. Risk factors for symptomatic VTE (sVTE) were analyzed via Chi-squared, univariate, and multivariate regression.

RESULTS

In total 33 patients presented with sVTE (25 DVT, 14 PE). Patients with sVTE had longer hospital stays (p < 0.01) and worse outcomes at one-month (p < 0.01) and three-month follow-up (p = 0.02). Univariate predictors of sVTE included male sex (p = 0.03), Hunt Hess score (p = 0.01), Glasgow Coma scale (p = 0.02), intracranial hemorrhage (p = 0.03), hydrocephalus requiring external ventricular drain (EVD) placement (p < 0.01), and mechanical ventilation (p < 0.01). Only hydrocephalus requiring EVD (p = 0.01) and ventilator use (p = 0.02) remained significant upon multivariate analysis. Patients with delayed heparin introduction were significantly more likely to sustain sVTE on univariate analysis (p = 0.02) with a trend-level significance on multivariate analysis (p = 0.07).

CONCLUSIONS

Patients with aSAH are more likely to develop sVTE following use of perioperative EVD or mechanical ventilation. sVTE leads to longer hospital stays and worse outcomes among patients treated for aSAH. Delayed heparin initiation increases the risk of sVTE. Our results may help guide surgical decision-making during recovery from aSAH and improve VTE-related postoperative outcomes.

Chemoprophylactic Anticoagulation Following Lumbar Surgery Significantly Reduces Thromboembolic Events After Instrumented Fusions, Not Decompressions

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To quantify any reduction in venous thromboembolic events (VTEs) caused by chemoprophylaxis among lumbar surgery patients.

SUMMARY OF BACKGROUND DATA

Chemoprophylactic anticoagulation (chemoprophylaxis) is used to prevent VTE after lumbar surgery. However, the treatment effect of chemoprophylaxis has not been reported among spine surgery patients, as conventional statistical methods preclude such inferences.

MATERIALS AND METHODS

A total of 1243 consecutive lumbar fusions and 1433 noninstrumented lumbar decompressions performed at our institution over a six-year period were identified, and clinical and demographic data were collected, including on VTE events within 30 days postoperatively. Instrumented lumbar fusions and noninstrumented lumbar surgeries were analyzed separately. Patients who were given chemoprophylaxis (treatment) and controls were matched according to known VTE risk factors, including age, body mass index, sex, diabetes, chronic kidney disease, history of VTE, estimated blood loss, length of surgery, transfusion, whether surgery was staged, and whether surgery used an anterior approach. K-nearest neighbor propensity score matching was performed, and the treatment effect of chemoprophylaxis was calculated.

RESULTS

Unadjusted, there was no difference in the rate of VTE between treatment and controls in either population. Baseline clinical and demographic characteristics differed significantly between treatment and control groups. In all, 575 lumbar fusion patients and 435 noninstrumented lumbar decompression patients were successfully propensity score matched, yielding balanced models (Rubin B <25, 0.5<Rubin R <2.0) and >60% reduction in known bias for both populations. The treatment effect of chemoprophylaxis after lumbar fusion in our patient population was a reduction in VTE incidence from 9.4% to 4.2% ( P <0.05), and propensity score adjusted regression confirmed a reduced odds of VTE with chemoprophylaxis (odds ratio=0.37, P =0.035). The treatment effect was not significant for noninstrumented lumbar decompression patients.

CONCLUSION

Among patients undergoing instrumented lumbar fusions, chemoprophylactic anticoagulation causes a significant reduction in VTE, but causes no significant reduction among patients undergoing noninstrumented lumbar decompression.

Pharmacological venous thromboembolism prophylaxis in elective cranial surgery: a systematic review of time of initiation, regimen and duration

INTRODUCTION

Pharmacological prophylaxis of venous thromboembolism (VTE) requires nuanced decision-making to balance the risk of VTE against haemorrhage. This problem is compounded in neurosurgical patients, in whom postoperative intracranial haemorrhage (ICH) may be catastrophic, compared to non-neuraxial bleeding in other types of surgery. Current major guidelines recommend caution when using pharmacological prophylaxis in elective cranial surgery, but incorporate low-quality evidence and lack precise guidance on timing and duration of anticoagulation.

METHODS

We aimed to answer the following questions for patients undergoing elective cranial surgery: (1) when is the optimal time to initiate postoperative anticoagulation, and (2) how long should postoperative anticoagulation be continued for? In this systematic review, we screened randomised and non-randomised studies reporting original data on pharmacological VTE prophylaxis in elective cranial surgery. Outcomes of interest were VTE and ICH.

RESULTS

Three retrospective, single-centre observational studies met eligibility criteria, with a total of 923 participants. Meta-analysis was not performed due to a high risk of bias across all studies. Through narrative synthesis, we found that patients who developed VTE were significantly more likely to receive their first postoperative dose at a later time (mean: 144 vs. 29 h, p = .04). Shorter courses of anticoagulation (<7 days) were associated with significantly lower ICH rates (p = .03) compared to longer courses (>21 days).

CONCLUSION

The limited evidence favours earlier initiation and shorter courses of thromboprophylactic anticoagulation. These findings are specific to patients undergoing surgery for meningioma or glioma and may not apply to other populations. Randomised controlled trials or robustly designed observational studies are necessary to establish a clearer evidence base.

Early Detection and Management of Venous Thrombosis in Skull Base Surgery: Role of Routine Doppler Ultrasound Monitoring

BACKGROUND

Venous thromboembolism (VTE), encompassing deep venous thrombosis (DVT) and pulmonary embolism (PE), causes postoperative morbidity and mortality in neurosurgical patients. The use of pharmacological prophylaxis for DVT prevention in the immediate postoperative period carries increased risk of intracranial hemorrhage, especially after skull base surgeries.

OBJECTIVE

To investigate the impact of routine Doppler ultrasound monitoring in prevention and tiered management of VTE after skull base surgery.

METHODS

We retrospectively analyzed a large cohort of consecutive adult patients who were prospectively and uniformly managed with routine monitoring by Doppler ultrasound for DVT after resection of a skull base tumor.

RESULTS

A total of 389 patients who underwent 459 surgeries for intracranial tumor resection were analyzed. Skull base meningioma was the most common pathology. Forty-four (9.59%) postoperative VTEs were detected: 9 (1.96%) with PE with or without DVT and 35 (7.63%) with DVT alone. Four cases of subsegmental PE were diagnosed without evidence of lower extremity DVT, possibly in the setting of peripherally inserted central catheters maintenance. One patient had a preoperative proximal DVT and underwent a prophylactic inferior vena cava filter but expired from PE after discharge. Prior history of VTE (risk ratio [RR] 5.13; 95% CI 2.76-7.18; P < .01), anesthesia duration (RR 1.14; 95% CI 1.03-1.27; P = .02), and blood transfusion (RR 1.95; 95% CI 1.01-3.37; P = .04) were associated with VTE development on multivariate analysis.

CONCLUSION

Routine postoperative venous ultrasound monitoring detects asymptomatic DVT guiding management. This is an alternative strategy to prescribing pharmacological VTE prophylaxis immediately after lengthy surgeries for intracranial tumors. Peripherally inserted central catheters were associated with subsegmental PE.

Multidisciplinary Bundle Approach in Venous Thromboembolism Prophylaxis in Patients with Non-Traumatic Subarachnoid Hemorrhage

Background

A venous thromboembolism (VTE) bundle was launched in 2016 at the University of Illinois Hospital aiming to reduce the rate of VTE in the neurosurgical ICU. Main elements of the bundle included correct and early use of intermittent pneumatic compression and subcutaneous heparin.

Methods

Patients with SAH were retrospectively identified from 2014 until 2018. VTE events were diagnosed using twice weekly lower-extremity venous Duplex ultrasound and chest computerized tomography when appropriate.

Results

A total of 133 patients was included in each group. The incidence of VTE was not significantly different before and after the bundle (15% vs. 12%, p = 0.47). No difference was found regarding new episode of intracranial hemorrhage secondary to SQH (1.5% vs. 2.1%, p = 0.65). Multivariate analysis demonstrated that longer ICU LOS, higher Caprini score, and presence of baseline lung diseases were associated with VTE development.

Conclusions

With a median Caprini score of 9, our patient population was found to be at high risk for developing VTE. The implementation of the VTE bundle did not significantly reduce the rate of VTE in patients with non-traumatic SAH at UIH.

Rate of Development of Venous Thromboembolism in Lateral Skull Base Surgery

OBJECTIVES

Venous thromboembolism (VTE) is a major cause of morbidity and mortality for surgical patients. This article aims to determine factors that may have contributed to the development of VTE in patients undergoing lateral skull base surgery, to assess the validity of the Caprini Risk Assessment Model (RAM) score in this subset of patients, and to determine the efficacy of mechanical DVT prophylaxis alone in preventing VTE.

STUDY DESIGN

Retrospective chart review.

METHODS

A retrospective chart review was conducted of patients who underwent skull base surgery for vestibular schwannoma, and the rate of VTE was assessed. Patient demographics, comorbidities, and treatment factors were examined to determine risk factors associated with the development of a postoperative thrombotic event. Caprini RAM scores were compared for patients who developed a VTE.

RESULTS

Among 197 patients, the rate of VTE formation was 3.5%. No individual risk factor independently contributed to the development of a thrombotic event. The mean Caprini RAM score was 4.06 in patients who did not develop a VTE and 5.14 in the patients that did develop a VTE (P = .005). The Caprini score was significant for the risk of VTE formation, with an odds ratio of 2.8 (P = .009, 95% CI = 1.3-6.2).

CONCLUSION

Venous thromboembolism rates are relatively low following lateral skull base surgery. While there is no individual risk factor associated with increased VTE risk, the Caprini RAM score appears to be a useful predictor of risk. The Caprini score may be useful in identifying high-risk patients who may benefit from chemoprophylaxis for VTE prevention.

LEVEL OF EVIDENCE

Level III-This is a retrospective chart review study Laryngoscope, 2021.

Thromboprophylaxis in critically ill patients: balancing on a tightrope

Venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism, is a common and potentially fatal complication in the intensive care unit (ICU). Critically ill patients have some special characteristics that increase the risk for VTE and complicate risk stratification and diagnosis. Given the positive effect of thromboprophylaxis on main outcomes, its use is mandatory in these patients, which is documented by various studies and recommended by all published guidelines. However, anticoagulation management is not an easy issue in clinical practice, as the critical patient may be at high risk for thrombosis or, conversely, at increased risk of bleeding or may balance between thrombotic and bleeding risk. Thrombotic and bleeding risk scoring should be evaluated daily in order to select the appropriate form of thromboprophylaxis. The selection depends on the degree of bleeding risk and the subgroup of ICU patients involved, such as patients with sepsis, acute brain injury, major trauma or coronavirus disease-2019. If there is no bleeding risk or other contraindication, the patient should receive pharmacologic thromboprophylaxis with unfractionated heparin or low molecular weight heparins, weighing the advantages of each agent. If the patient is at high risk of bleeding or there is a contraindication to pharmacologic prophylaxis, he should receive mechanical thromboprophylaxis mainly with intermittent pneumatic compression or graduated compression stockings. Thromboprophylaxis compliance with the guidelines is a prerequisite for moving from theory to practice. Direct oral anticoagulants have been studied in ICU patients and have no place at present in VTE prophylaxis requiring further research.

Early chemoprophylaxis for deep venous thrombosis does not increase the risk of hematoma expansion in patients presenting with spontaneous intracerebral hemorrhage

Background:

Spontaneous intracerebral hemorrhage (ICH) is a significant cause of morbidity and mortality worldwide. The development of venous thromboembolism (VTE), including deep venous thrombosis or pulmonary embolism, is correlated with negative outcomes following ICH. Due to the risk of hematoma expansion associated with the use of VTE chemoprophylaxis, there remains significant debate about the optimal timing for its initiation following ICH. We analyzed the risk of early chemoprophylaxis on hematoma expansion following ICH.

Methods:

We performed a retrospective analysis of patients presenting with spontaneous ICH at single institution between 2011 and 2018. The rate of hematoma expansion was compared between patients that received early chemoprophylaxis (on admission) and those that received conventional chemoprophylaxis (>24 h).

Results:

Data for 235 patients were available for analysis. Eleven patients (7.5%) in the early prophylaxis cohort and seven patients (8.0%) in the conventional prophylaxis cohort developed VTE (P = 0.9). Hematoma expansion also did not differ significantly (early 19%, conventional 23%, P = 0.5).

Conclusion:

The use of early chemoprophylaxis against venous thromboembolic events following ICH appears safe in our patient population without increasing the risk of hematoma expansion. Given the increased risk of poor outcome in the setting of VTE, early VTE chemoprophylaxis should be considered in patients who present with ICH. Larger, prospective, and randomized studies are necessary to better elucidate the risk of early chemoprophylaxis and potential reduction in venous thromboembolic events.

Risk factors for venous thromboembolism induced by prolonged bed rest during interstitial brachytherapy for gynecological cancer: a retrospective study

Background

Screening and management of venous thromboembolism (VTE) after surgery is important in preventing sublethal VTE. However, the risk factors for VTE during interstitial brachytherapy (ISBT) remain unknown, and appropriate screening and management strategies are yet to be established. Therefore, this study aimed to evaluate the risk factors for VTE resulting from requisite bed rest during ISBT for gynecologic cancers.

Methods

We retrospectively analyzed 47 patients. For patients without definitive preceding radiotherapy, whole pelvic irradiation (30–50 Gy) followed by ISBT of 12–30 Gy/2–5 fx/1–3 days was administered to CTV D90. For patients with preceding radiotherapy, 36–42 Gy/6–7 fx/3–4 days was delivered by ISBT alone. The supine position was required during ISBT. D-dimer (DD) was measured at initial presentation, 1 week before ISBT, pre-ISBT, on the day of, and the day following needle removal. Patients were divided into three groups according to the risk of VTE and were managed accordingly; Group 1: DD was not detected (negative) before ISBT, Group 2: VTE was not detected on venous ultrasound imaging, although DD was positive before ISBT, and Group 3: VTE was detected (positive) before ISBT. An intermittent pneumatic compression device was used during ISBT; for the patients without VTE before ISBT. Heparin or oral anticoagulants were administered to patients with VTE before ISBT.

Results

Overall, the median values of DD pre-ISBT, on the day of, and on the day following needle removal were 1.0 (0.4–5.8), 1.1 (0.5–88.9), and 1.5 (0.7–40.6) μg/mL, respectively. After ISBT, no patients had deep vein thrombosis (DVT) in groups 1 and 2. In group 3, 7 of 14 patients experienced worsening of VTE but remained asymptomatic. In univariate analysis, DVT diagnosed before ISBT, Caprini score ≥ 7, and difference in DD values between pre-ISBT and the day of or the day following needle removal ≥ 1 were associated with the incidence or worsening of VTE.

Conclusion

DD should be measured before and after ISBT to detect the incidence or worsening of VTE in patients with DVT. The Caprini score may help in the prediction of VTE during or after ISBT.

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.

Pharmacologic thromboprophylaxis in adult patients undergoing neurosurgical interventions for preventing venous thromboembolism

The impact of pharmacologic prophylaxis for venous thromboembolism in patients undergoing neurosurgical intervention remains uncertain. We reviewed the efficacy and safety of pharmacologic compared with nonpharmacologic thromboprophylaxis in neurosurgical patients. Three databases were searched through April 2018, including those for randomized controlled trials (RCTs) and for nonrandomized controlled studies (NRSs). Independent reviewers assessed the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Seven RCTs and 3 NRSs proved eligible. No studies reported on symptomatic proximal and distal deep vein thrombosis (DVT). Two RCTs reported on screening-detected proximal and distal DVTs. We used the findings of these 2 RCTs as the closest surrogate outcomes to inform the proximal and distal DVT outcomes. These 2 RCTs suggest that pharmacologic thromboprophylaxis may decrease the risk of developing asymptomatic proximal DVT (relative risk [RR], 0.50; 95% confidence interval [CI], 0.30-0.84; low certainty). Findings were uncertain for mortality (RR, 1.27; 95% CI, 0.57-2.86; low certainty), symptomatic pulmonary embolism (PE) (RR, 0.84; 95% CI, 0.03-27.42; very low certainty), asymptomatic distal DVT (RR, 0.54; 95% CI, 0.27-1.08; very low certainty), and reoperation (RR, 0.43; 95% CI, 0.06-2.84; very low certainty) outcomes. NRSs also reported uncertain findings for whether pharmacologic prophylaxis affects mortality (RR, 0.72; 95% CI, 0.46-1.13; low certainty) and PE (RR, 0.18; 95% CI, 0.01-3.76). For risk of bleeding, findings were uncertain in both RCTs (RR, 1.57; 95% CI, 0.70-3.50; low certainty) and NRSs (RR, 1.45; 95% CI, 0.30-7.12; very low certainty). In patients undergoing neurosurgical procedures, low certainty of evidence suggests that pharmacologic thromboprophylaxis confers benefit for preventing asymptomatic (screening-detected) proximal DVT with very low certainty regarding its impact on patient-important outcomes.

Venous Thromboembolism Prophylaxis in Elective Neurosurgery: A Survey of Board-Certified Neurosurgeons in the United States and Updated Literature Review

BACKGROUND

Venous thromboembolism (VTE) remains the single most important preventable cause of morbidity and mortality following neurosurgical procedures, with an incidence of approximately 16%. In the absence of stringent guidelines, the variation in current practice patterns could be considerable and was the underlying basis for this study.

OBJECTIVES

Our objective is to evaluate the modality of thromboprophylaxis used by neurosurgeons.

METHODS

In line with "CHERRIES" (Checklist for Reporting Results of Internet E-Surveys) guidelines, an online survey regarding postoperative VTE prophylaxis following elective neurosurgical procedures was created using Google Forms and distributed to 1500 board-certified neurosurgeons in the United States.

RESULTS

A total of 370 board-certified neurosurgeons (24.7%) responded to the survey. Sequential compression device was the only primary method of thromboprophylaxis used by 27.2% and 26.5% of respondents after elective craniotomy for tumor resection and spine surgery, respectively. Of the chemical prophylaxis, subcutaneous heparin 5000 U every 8 hours was the most commonly used medication followed by enoxaparin 40 mg daily. Most responders were comfortable starting chemical prophylaxis on postoperative day 1, followed by day 2 and day 3 in both types of surgeries. The mean postoperative time of chemical prophylaxis initiation was significantly more delayed by respondents with longer years in practice.

CONCLUSIONS

This study highlights the variation in practice between neurosurgeons in managing postoperative VTE prophylaxis after elective spine and cranial surgeries. In lieu of this variation, our results showed that most neurosurgeons are comfortable starting chemical prophylaxis as soon as postoperative day 1 following both types of procedures.

Perioperative Venous Thromboembolism Prophylaxis

Venous thromboembolism (VTE) is a preventable cause of postoperative morbidity and mortality; however, audits suggest that the use of thromboprophylaxis is underused. In this review, we describe our approach to prevention of postoperative VTE and provide guidance on how to formulate an optimal VTE prophylaxis plan. We recommend that all patients undergo thrombosis- and bleeding-risk assessment as part of their preoperative evaluation. The risk of thrombosis can be estimated based on patient- and procedure-specific factors, using validated risk-assessment models such as the Caprini score. There are no validated models to predict perioperative bleeding; however, several risk factors have been proposed. Patients should ambulate early and frequently after surgery. We recommend no additional prophylaxis in patients at very low risk of VTE (Caprini score 0). Patients at low risk of VTE (Caprini 1 to 2) are recommended to receive either mechanical or pharmacological prophylaxis. Patients at moderate (Caprini 3 to 4) to high risk of VTE (Caprini ≥5) are recommended pharmacological prophylaxis either alone or combined with mechanical prophylaxis. Patients at high risk of bleeding should receive mechanical prophylaxis until their risk of bleeding is reduced and pharmacological prophylaxis can be reconsidered. Populations for which the Caprini score has not been validated (such as orthopedic surgery) are recommended prophylaxis based on individual and procedure-specific risk factors. Prophylaxis is typically continued until the patient is ambulatory or until hospital dismissal; however, longer durations can be considered in certain circumstances (high-risk patients undergoing malignant abdominopelvic operations, bariatric operations, and certain orthopedic operations).

Systematic review and meta-analysis of the clinical utility of Enhanced Recovery After Surgery pathways in adult spine surgery

OBJECTIVE

Spine surgery has been identified as a significant source of healthcare expenditures in the United States. Prolonged hospitalization has been cited as one source of increased spending, and there has been drive from providers and payors alike to decrease inpatient stays. One strategy currently being explored is the use of Enhanced Recovery After Surgery (ERAS) protocols. Here, the authors review the literature on adult spine ERAS protocols, focusing on clinical benefits and cost reductions. They also conducted a quantitative meta-analysis examining the following: 1) length of stay (LOS), 2) complication rate, 3) wound infection rate, 4) 30-day readmission rate, and 5) 30-day reoperation rate.

METHODS

Using the PRISMA guidelines, a search of the PubMed/Medline, Web of Science, Cochrane Reviews, Embase, CINAHL, and OVID Medline databases was conducted to identify all full-text articles in the English-language literature describing ERAS protocol implementation for adult spine surgery. A quantitative meta-analysis using random-effects modeling was performed for the identified clinical outcomes using studies that directly compared ERAS protocols with conventional care.

RESULTS

Of 950 articles reviewed, 34 were included in the qualitative analysis and 20 were included in the quantitative analysis. The most common protocol types were general spine surgery protocols and protocols for lumbar spine surgery patients. The most frequently cited benefits of ERAS protocols were shorter LOS (n = 12), lower postoperative pain scores (n = 6), and decreased complication rates (n = 4). The meta-analysis demonstrated shorter LOS for the general spine surgery (mean difference -1.22 days [95% CI -1.98 to -0.47]) and lumbar spine ERAS protocols (-1.53 days [95% CI -2.89 to -0.16]). Neither general nor lumbar spine protocols led to a significant difference in complication rates. Insufficient data existed to perform a meta-analysis of the differences in costs or postoperative narcotic use.

CONCLUSIONS

Present data suggest that ERAS protocol implementation may reduce hospitalization time among adult spine surgery patients and may lead to reductions in complication rates when applied to specific populations. To generate high-quality evidence capable of supporting practice guidelines, though, additional controlled trials are necessary to validate these early findings in larger populations.

Role of anaesthesia in neurosurgical enhanced recovery programmes

The application of Enhanced Recovery After Surgery (ERAS) in neurosurgical practice is a relatively new concept. A limited number of studies involving ERAS protocols within neurosurgery, specifically for elective craniotomy, have been published, contrary to the ERAS spine surgery pathways that are now promoted by numerous national and international dedicated surgical societies and hospitals. In this review, we want to present the patient surgical journey from an anaesthesia perspective through the key components that can be included in the ERAS pathways for neurosurgical procedures, both craniotomies and major spine surgery.

Prophylactic unfractionated heparin and hemorrhage in neurocritically ill underweight patients: A case series and review of the literature

PURPOSE

Three cases of major bleeding associated with thromboprophylactic unfractionated heparin (UFH) therapy in underweight neurocritically ill patients are reported.

SUMMARY

Three underweight patients (body mass index of <18.5 kg/m2) were treated in the intensive care unit with major bleeds associated with UFH thromboprophylaxis. Two of the patients, a 76-year-old female and a 56-year-old female, had hemorrhages on presentation; the third patient, a 29-year-old male, developed bleeding during his admission. All 3 patients had past medical histories consisting of acute neurologic conditions within 6 weeks of presentation, including subdural hematoma, subarachnoid hemorrhage, and obstructive hydrocephalus secondary to a brain mass. All hemorrhages developed following the receipt of prophylactic UFH at doses of 5,000 units every 8 to 12 hours, which translated to high weight-based dosages (>300 units/kg/d). Additionally, hemorrhages were associated with prolonged activated partial thromboplastin time, which declined following heparin discontinuation. The major bleeds following UFH administration included an acute on chronic subdural hematoma, acute rectus sheath hematoma, and cerebellar hematoma. Stabilization of the subdural hematoma was achieved without the use of protamine and the patient was discharged in stable condition. The other 2 patients expired secondary to their hemorrhagic events. Naranjo nomogram scores for the patients indicated that heparin was the probable cause of bleed in 2 cases and a possible cause in 1 case.

CONCLUSION

Three major hemorrhages developed following the administration of UFH. Underweight patients with neurologic injury may require increased clinical vigilance, reduced doses, and pharmacodynamic monitoring to improve safety outcomes associated with thromboprophylaxis.

Comparative efficacy and safety of pharmacological prophylaxis and intermittent pneumatic compression for prevention of venous thromboembolism in adult undergoing neurosurgery: a systematic review and network meta-analysis

Whether intermittent pneumatic compression (IPC) is a more effective form of thromboprophylaxis than anticoagulants in individuals undergoing neurosurgery remains controversial. Relevant studies are sparse and inconsistent. Therefore, direct comparisons are difficult to perform and impractical. Hence, we summarized and compared the efficacy and safety of IPC and anticoagulants for the prevention of venous thromboembolism (VTE) in adults undergoing cranial or spinal procedures. Several electronic databases were searched for randomized controlled trials on the use of IPC and anticoagulants for thromboembolism prevention in neurosurgical patients, from inception to August 6, 2019. Studies reporting the selected endpoints were included in direct and Bayesian network meta-analyses to estimate the relative effects of the interventions. Overall, our analysis included 18 trials comprising 2474 patients. Both IPC (RR, 0.41; 95% CrI, 0.26-0.60) and chemical prophylaxis (RR, 0.48; 95% CrI, 0.28-0.68) were found to be more efficacious than the placebo in reducing the risk of deep vein thrombosis (DVT). In addition, our analysis also demonstrated that both IPC (RR, 0.10; 95% CrI, 0.01-0.60) and chemical prophylaxis (RR, 0.31; 95% CrI, 0.05-1.00) reduced the risk of pulmonary embolism (PE) significantly more than the placebo. Based on the available evidence of moderate-to-good quality, IPC is equivalent to anticoagulants for thromboprophylaxis in terms of efficacy. Evidence to support or negate the use of pharmacological prophylaxis in terms of safety is lacking. The results of ongoing and future large randomized clinical trials are needed.

Management of cancer-related thrombosis in the era of direct oral anticoagulants: A comprehensive review of the 2019 ITAC-CME clinical practice guidelines. On behalf of the Groupe Francophone Thrombose et Cancer (GFTC)

Venous thromboembolism (VTE) is a common disease complication in cancer patients and the second cause of death after cancer progression. VTE management and prophylaxis are critical in cancer patients, but effective therapy can be challenging because these patients are at higher risk of VTE recurrence and bleeding under anticoagulant treatment. Numerous published studies report inconsistent implementation of existing evidence-based clinical practice guidelines (CPG), including underutilization of thromboprophylaxis, and wide variability in clinical practice patterns across different countries and various practitioners. This review aims to summarize the 2019 ITAC-CME evidence-based CPGs for treatment and prophylaxis of cancer-related VTE, which include recommendations on the use of direct oral anticoagulants specifically in cancer patients. The guidelines underscore the gravity of developing VTE in cancer and recommend the best approaches for treating and preventing cancer-associated VTE, while minimizing unnecessary or over-treatment. Greater adherence to the 2019 ITAC guidelines could substantially decrease the burden of VTE and improve survival of cancer patients.

American Society of Hematology 2019 guidelines for management of venous thromboembolism: prevention of venous thromboembolism in surgical hospitalized patients

BACKGROUND

Venous thromboembolism (VTE) is a common source of perioperative morbidity and mortality.

OBJECTIVE

These evidence-based guidelines from the American Society of Hematology (ASH) intend to support decision making about preventing VTE in patients undergoing surgery.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic reviews. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 30 recommendations, including for major surgery in general (n = 8), orthopedic surgery (n = 7), major general surgery (n = 3), major neurosurgical procedures (n = 2), urological surgery (n = 4), cardiac surgery and major vascular surgery (n = 2), major trauma (n = 2), and major gynecological surgery (n = 2).

CONCLUSIONS

For patients undergoing major surgery in general, the panel made conditional recommendations for mechanical prophylaxis over no prophylaxis, for pneumatic compression prophylaxis over graduated compression stockings, and against inferior vena cava filters. In patients undergoing total hip or total knee arthroplasty, conditional recommendations included using either aspirin or anticoagulants, as well as for a direct oral anticoagulant over low-molecular-weight heparin (LMWH). For major general surgery, the panel suggested pharmacological prophylaxis over no prophylaxis, using LMWH or unfractionated heparin. For major neurosurgery, transurethral resection of the prostate, or radical prostatectomy, the panel suggested against pharmacological prophylaxis. For major trauma surgery or major gynecological surgery, the panel suggested pharmacological prophylaxis over no prophylaxis.

Defects in Processes of Care for Pharmacologic Prophylaxis Are Common Among Neurosurgery Patients Who Develop In-Hospital Postoperative Venous Thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is a cause of considerable morbidity and mortality in hospitalized patients. An evidence-based algorithm was developed and implemented at our institution to guide perioperative VTE prophylaxis management.

OBJECTIVE

We evaluated compliance with prescription of risk-appropriate VTE prophylaxis and administration of prescribed VTE prophylaxis in neurosurgery patients.

METHODS

This was a retrospective analysis of postoperative neurosurgery patients at a single institution with subsequent diagnosis of acute VTE during their inpatient stay. Descriptive statistics were used to characterize pharmacologic VTE prophylaxis and prescribing patterns.

RESULTS

The incidence of VTE in our neurosurgery population was 248/13,913 (1.8%). Of the 123 patients, the median time to VTE diagnosis was 96 hours after surgery (interquartile range [IQR], 58-188 hours). A total of 108 patients (87.8%) were prescribed risk-appropriate VTE prophylaxis, among whom 61 (56.5%) received all doses as prescribed. Fifty-three patients (43.1%) missed ≥1 dose of prescribed prophylaxis and the median missed doses was 3 (IQR, 0-3). The median time to first dose of pharmacologic VTE prophylaxis was 42 hours (IQR, 28-51). More than half (n = 63, 51.2%) of the VTE risk assessments contained ≥1 error, of which 15 (23.8%) would have resulted in a change in recommendation.

CONCLUSIONS

Our evidence-based VTE prophylaxis algorithm was not accurately completed in more than half of patients. Many patients who developed VTE had a defect in their VTE prophylaxis management during their inpatient stay. Research to improve optimal VTE prevention practice in neurosurgery patients is needed.

Application of the Caprini Risk Assessment Model for Evaluating Postoperative Deep Vein Thrombosis in Patients Undergoing Plastic and Reconstructive Surgery

BACKGROUND

The optimal approach for assessing the risk of venous thromboembolism (VTE) in patients undergoing plastic surgery is yet to be established. This study aimed to determine the validity of the Caprini Risk Assessment Scale in identifying patients undergoing plastic surgery who are at a high risk of developing VTE.

METHODS

Between December 2014 and November 2015, we enrolled 90 patients. Risk factors for VTE were assessed at baseline. The Caprini Risk Assessment Model was used to stratify patients into Caprini <4, Caprini 5-6, Caprini 7-8, and Caprini >8 groups before examination. We preoperatively screened for deep vein thrombosis (DVT) using duplex ultrasound. During operation, surgical duration and blood loss were recorded. Duplex ultrasound was repeated 2 and 7 days postoperatively to evaluate for DVT. We used a univariate analysis to determine risk factors for postoperative VTE. Confounding predictors were finally tested using a multivariate logistic regression analysis.

RESULTS

One patient had preoperative DVT and was excluded from the study. Eighty-nine patients were included in the final analyses. Of the 89 patients, 7 (8%) developed postoperative DVT. Mean age, body mass index, Caprini score, and surgical duration were significantly higher in patients who developed postoperative DVT. Variables associated with increased risk of postoperative DVT using univariate analysis were Caprini scores of 7-8 and >8. Multivariate logistic regression analysis finally identified Caprini scores 7-8 [odds ratio (OR) 13, 95% confidence interval (CI) 1.67-101.98, P = 0.014] and >8 (OR 19.5, 95% CI 1.02-371.96, P = 0.048) to be independently associated with postoperative DVT.

CONCLUSIONS

Although the incidence of postoperative DVT is relatively low among patients undergoing plastic surgery, Caprini scores can be used to predict postoperative VTE complications.

Risks, Benefits, and the Optimal Time to Resume Deep Vein Thrombosis Prophylaxis in Patients with Intracranial Hemorrhage

Introduction It is common to start all patients on chemical prophylaxis for deep vein thrombosis (DVT) in order to decrease the risk of venous thromboembolism (VTE) and the associated adverse effects, including the potential for fatal pulmonary embolism (PE). There is no consensus in the literature on the optimal time to resume chemical DVT prophylaxis in patients who present with intracranial hemorrhage requiring neurosurgical intervention. The practice is variable and practitioner dependent. There can be difficulty in balancing the increased risk of further intracranial hemorrhage versus the benefit of starting DVT prophylaxis to prevent VTE. Method A retrospective review of patients that had diagnosis of intracranial hemorrhage (ICH) defined as epidural hematoma (EDH), subdural hematoma (SDH), or intra-parenchymal hematoma (IPH), was performed using the neurosurgical census at our institution. The review consisted of adult patients greater than 18 years old with a diagnosis of intracranial hemorrhage. Type of intracranial hemorrhage, method of neurosurgical intervention (whether surgical, bedside procedure, or both), day post-procedure prophylaxis was resumed, and the type of chemical prophylaxis used (subcutaneous heparin (SQH) versus enoxaparin) were recorded. The patient's sex, Glasgow Coma Scale on presentation and discharge, length of hospital stay, and length of intensive care unit (ICU) stay were also recorded. Patients with previously diagnosed bleeding dyscrasia, previously diagnosed DVT or PE, patients without post-procedure cranial imaging (CT or MRI), and patients without post-procedure duplex ultrasound for DVT screening were excluded. Patients were monitored with head CT for possible expansion of ICH after resumption of therapy. Furthermore, we investigated whether the patient developed an adverse effect such as venous thromboembolism including deep vein thrombosis and/or pulmonary embolism during the post-procedure period when they were not on chemical prophylaxis. Results A total of 94 patients were analyzed in our study. Nine (9.6%) had an EDH, seventeen (18.1%) had an IPH, and sixty-eight (72.3%) had a SDH. The three most common procedures were craniectomy (28.7%), craniotomy (34%), and subdural drain placement (28.7%). The most common agent for chemical DVT prophylaxis was SQH in 78% of patients. There was no statistically significant association between type of chemical DVT prophylaxis used with respect to either ICU length of stay or hospital length of stay. Change in GCS (the difference of GCS on presentation versus on discharge) was found to have statistically significant relationship with the use of chemical DVT prophylaxis. Furthermore, patients were found to have no statistically significant association with re-bleed or new hemorrhage upon starting chemical DVT prophylaxis, regardless of the type of ICH. Conclusion The rates of DVT diagnosis did not seem to be significantly affected by the specific type of chemical prophylaxis that was used. ICU and hospital length of stay were not adversely affected by starting prophylaxis for VTE in patients with ICH. On the contrary, an improvement in GCS (on presentation versus discharge) was associated with starting chemical DVT prophylaxis in ICH patients within 24 hours post-procedure.

Is pharmacological anticoagulant prophylaxis necessary for adolescent idiopathic scoliosis surgery?

We report the outcomes of mechanical prophylaxis and chemoprophylaxis in patients who underwent elective surgery for idiopathic adolescent scoliosis (AIS).We retrospectively studied the patients who underwent posterior spinal instrumentation for AIS. The patients were divided into three groups: Group A low-molecular-weight heparin (LMWH) started at 8 hours after surgery; Group B LMWH started at 24 hr after surgery; Group C did not receive chemoprophylaxis. The data about wound oozing, need for transfusion, preoperative and postoperative hemoglobin level, length of stay in hospital, interval from the surgery to removal of closed suction drainage tube, postoperative blood loss from closed suction drain, deep venous thrombosis (DVT), and pulmonary embolism (PE) were investigated.The mean age and Lenke classification for all the groups were similar. No DVT or PE was detected in any group. The mean blood loss from the drain was higher in Group A (400 mL) and Group B (450 mL) when compared to Group C (150 mL) (P = .001). There were more wound oozing in Groups A (5) and B (6) than in Group C (3) (P = .585). Three patients in Group B, 3 patients in Group A, and no patient in Group C had superficial infections. However, there was no statistical difference between the groups (P = .182). Postoperative hospital stay was significantly longer in Groups A (6 days) and B (6 days) then in Group C (5 days) (P = .001).Our current study claims that chemoprophylaxis is not necessary for the patients without risk factors after AIS surgery. Early mobilization and mechanoprophylaxis represents adequate prophylaxis in addition to pain management and well hydration in patients' routine treatment. The complications of chemoprophylaxis are not correlated to the initiation time of prophylaxis.

Predictors of Venous Thromboembolism After Nonemergent Craniotomy: A Nationwide Readmission Database Analysis

BACKGROUND

Venous thromboembolism (VTE) is responsible for many hospital readmissions each year, particularly among postsurgical cohorts. Because early and indiscriminate VTE prophylaxis carries catastrophic consequences in postcraniotomy cohorts, identifying factors associated with a high risk for thromboembolic complications is important for guiding postoperative management.

OBJECTIVE

To determine VTE incidence in patients undergoing nonemergent craniotomy and to evaluate for factors that predict 30-day and 90-day readmission with VTE.

METHODS

The 2010-2014 cohorts of the Nationwide Readmissions Database were used to generate a large heterogeneous craniotomy sample.

RESULTS

There were 89,450 nonemergent craniotomies that met inclusion criteria. Within 30 days, 1513 patients (1.69%) were readmitted with VTE diagnoses; among them, 678 (44.8%) had a diagnosis of deep vein thrombosis alone, 450 (29.7%) had pulmonary embolism alone, and 385 (25.4%) had both. The corresponding 30-day deep vein thrombosis and pulmonary embolism incidences were 1.19% and 0.93%, respectively. In multivariate analysis, several factors were significantly associated with VTE readmission, namely, craniotomy for tumor, corticosteroids, advanced age, greater length of stay, and discharge to institutional care.

CONCLUSIONS

Craniotomies for tumor, corticosteroids, advanced age, prolonged length of stay, and discharge to institutional care are significant predictors of VTE readmission. The implication of steroids, coupled with their ubiquity in neurosurgery, makes them a potentially modifiable risk factor and a prime target for VTE reduction in craniotomy cohorts. Furthermore, the fact that dose is proportional to VTE risk in the literature suggests that careful consideration should be given toward decreasing regimens in situations in which use of a lower dose might prove equally sufficient.

Chemical venous thromboembolism prophylaxis in neurosurgical patients: an updated systematic review and meta-analysis

OBJECTIVE

Venous thromboembolism (VTE) is a common and potentially life-threatening complication. The risk of serious hemorrhagic complications when starting chemical prophylaxis for VTE prevention is a substantial concern for neurosurgeons. The objective of this study was to perform an updated systematic review and meta-analysis to determine if the rates of VTE and bleeding complications are different in patients undergoing chemoprophylaxis compared with placebo or mechanical prophylaxis alone following cranial or spinal procedures.

METHODS

In February 2016 a systematic literature review was performed identifying 3944 articles from 4 different databases. A random-effects meta-analysis was performed after identifying the articles that met inclusion criteria.

RESULTS

Nine articles that met the inclusion criteria were included. The quality of the studies was good, with all of them being classified as Level 2 evidence, with moderate Jadad scores. A meta-analysis comparing chemoprophylaxis with placebo in the prevention of deep venous thrombosis showed a significant benefit to chemical prophylaxis (OR 0.51, 95% CI 0.37–0.71; p < 0.0001). No significant increase in major intracranial hemorrhage (p = 0.60), major extracranial hemorrhage (p = 0.98), or minor bleeding complications (p = 0.60) was found.

CONCLUSIONS

Based on moderate-to-good quality of evidence, chemoprophylaxis is beneficial in preventing VTE, with no significant increase in either major or minor bleeding complications in patients undergoing cranial and spinal procedures. Further research is needed to determine whether this conclusion holds true for more specific subpopulations.

The Prophylaxis of Venous Thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is the third most common cardiovascular condition, after myocardial infarction and stroke. Prophylactic measures in accordance with current guidelines can significantly reduce the risk of VTE and the associated morbidity and mortality. Until now, the German interdisciplinary, evidence- and consensus-based (S3) clinical practice guideline on VTE prophylaxis was based on a complete review of all pertinent literature available in MEDLINE up to January 2008. More recent publications and drug approvals have made a thorough revision necessary.

METHODS

A systematic search was carried out in the MEDLINE and Embase databases for publications that appeared from 1 January 2008 to 7 August 2013. Updates of 5 national and international reference guidelines and 2 new Health Technology Assessment (HTA) reports were considered as well. A structured consensus-finding process was carried out with delegates from 27 scientific medical societies and from the Union of Medical Specialist Associations.

RESULTS

46 randomized controlled trials (RCTs) were included for critical appraisal. New findings led to re-evaluation of the value of compression stockings in combination with pharmacological prophylaxis (open recommendation), and suggest equal value of non-vitamin K antagonist oral anticoagulants (NOACs) and low molecular weight heparins (LMWH) or fondaparinux in elective hip and knee replacement (strong recommendation). For patients undergoing hip fracture surgery, we recommend LMWH or fondaparinux.

CONCLUSION

Further research is needed to assess the value of NOACs for pharmacological prophylaxis in orthopedic/trauma patients undergoing surgical procedures other than the ones mentioned above, and into the benefit and harm of new devices available for mechanical prophylaxis. The stringent implementation of basic measures such as early mobilization, movement exercises, and patient instruction is a key point to prevent venous thrombo - embolism.

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.

The risk of postoperative hemorrhage and efficacy of heparin for preventing deep vein thrombosis and pulmonary embolism in adult patients undergoing neurosurgery: a systematic review and meta-analysis

The aim of this meta-analysis was to examine the risk of postoperative bleeding and efficacy of heparin for preventing deep vein thrombosis (DVT) and pulmonary embolism (PE) in adult patients undergoing neurosurgery. MEDLINE, Cochrane, and EMBASE databases were searched until October 31, 2016, for randomized controlled trials (RCTs) and non-randomized comparative studies that assessed the rates of postoperative hemorrhage, DVT, PE, and mortality in adult patients undergoing neurosurgery. Nine eligible studies (five RCTs, four retrospective studies) including 874 patients treated with either unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) and 1033 patients in control group (placebo with or without compression device) were analyzed. The overall analysis revealed that there was an increase in the risk of postoperative hemorrhage in patients who received heparin (pooled OR 1.66, 95% CI 1.01 to 2.72, p=0.046) compared with no treatment group. The risk of postoperative hemorrhage was more significant if only RCTs were included in analysis. Heparin prophylaxis was associated with a decrease in the risk of DVT (pooled OR 0.48, 95% CI 0.36 to 0.65, p<0.001) and PE (pooled OR 0.25, 95% CI 0.09 to 0.73, p=0.011) but it did not affect the rate of mortality. In conclusion, heparin increased the rate of postoperative bleeding, decreased the risk of DVT, PE and venous thromboembolic event (VTE) but it did not affect the mortality of patients undergoing neurosurgery. For the heparin prophylaxis, the trade-off between the risk of postoperative bleeding and benefit of prophylaxis against VTEs requires further investigation.

Risk of deep venous thrombosis in elective neurosurgical procedures: a prospective, Doppler ultrasound-based study in children 12 years of age or younger

OBJECTIVE The risk of venous thromboembolism (VTE) from deep venous thrombosis (DVT) is significant in neurosurgical patients. VTE is considered a leading cause of preventable hospital deaths and preventing DVT is a closely monitored quality metric, often tied to accreditation, hospital ratings, and reimbursement. Adult protocols include prophylaxis with anticoagulant medications. Children's hospitals may adopt adult protocols, although the incidence of DVT and the risk or efficacy of treatment is not well defined. The incidence of DVT in children is likely less than in adults, although there is very little prospectively collected information. Most consider the risk of DVT to be extremely low in children 12 years of age or younger. However, this consideration is based on tradition and retrospective reviews of trauma databases. In this study, the authors prospectively evaluated pediatric patients undergoing a variety of elective neurosurgical procedures and performed Doppler ultrasound studies before and after surgery. METHODS A total of 100 patients were prospectively enrolled in this study. All of the patients were between the ages of 1 month and 12 years and were undergoing elective neurosurgical procedures. The 91 patients who completed the protocol received a bilateral lower-extremity Doppler ultrasound examination within 48 hours prior to surgery. Patients did not receive either medical or mechanical DVT prophylaxis during or after surgery. The ultrasound examination was repeated within 72 hours after surgery. An independent, board-certified radiologist evaluated all sonograms. We prospectively collected data, including potential risk factors, details of surgery, and details of the clinical course. All patients were followed clinically for at least 1 year. RESULTS There was no clinical or ultrasound evidence of DVT or VTE in any of the 91 patients. There was no clinical evidence of VTE in the 9 patients who did not complete the protocol. CONCLUSIONS In this prospective study, no DVTs were found in 91 patients evaluated by ultrasound and 9 patients followed clinically. While the study is underpowered to give a definitive incidence, the data suggest that the risk of DVT and VTE is very low in children undergoing elective neurosurgical procedures. Prophylactic protocols designed for adults may not apply to pediatric patients. Clinical trial registration no.: NCT02037607 (clinicaltrials.gov).

Postoperative Thromboembolic Prophylaxis with Low-Molecular-Weight Heparin and Risk of Rebleeding in Patients with Chronic Subdural Hematomas: A Comparative Retrospective Cohort Study

OBJECTIVE

Early postoperative administration of low-molecular-weight heparin (LMWH) to prevent thromboembolic events in patients with chronic subdural hematoma (CSDH) is controversial. Our goal was to investigate impact of early postoperative LMWH administration on recurrence rate of CSDHs.

METHODS

Retrospective review was performed of 136 patients with CSDHs who were operated on during an 18-month period. Early postoperative administration of LMWH was at the discretion of the treating surgeon. This resulted in patients treated (heparin [H] group) or not treated with LMWH (no heparin [NH] group). All patients underwent imaging 4 weeks after surgery or earlier in cases of deterioration. The primary outcome variable was reoperation. Secondary outcomes were reoperation, important residual hematoma (defined as hematoma depth of more than one third of original size), and incidence of thromboembolic complications. Relative risk and absolute risk reduction were calculated.

RESULTS

We included 105 patients, 50 (47.6%) in the NH group and 55 (52.4%) in the H group. Nine patients (18%) in the NH group and 6 patients (10.9%) in the H group required secondary surgery (relative risk 0.61, 95% confidence interval 0.23-1.58, P = 0.404, absolute risk reduction 0.07). Eleven patients (22%) in the NH group and 15 patients (27.3%) in the H group presented with important residual hematoma or underwent surgery for hematoma recurrence (relative risk 1.24, 95% confidence interval 0.63-2.44, P = 0.532, absolute risk reduction -0.05).

CONCLUSIONS

Our data provide preliminary evidence that early postoperative administration of LWMH does not increase risk of clinically relevant recurrence of CSDHs.

Prophylaxis of Venous Thrombosis in Neurocritical Care Patients: An Evidence-Based Guideline: A Statement for Healthcare Professionals from the Neurocritical Care Society

The risk of death from venous thromboembolism (VTE) is high in intensive care unit patients with neurological diagnoses. This is due to an increased risk of venous stasis secondary to paralysis as well as an increased prevalence of underlying pathologies that cause endothelial activation and create an increased risk of embolus formation. In many of these diseases, there is an associated risk from bleeding because of standard VTE prophylaxis. There is a paucity of prospective studies examining different VTE prophylaxis strategies in the neurologically ill. The lack of a solid evidentiary base has posed challenges for the establishment of consistent and evidence-based clinical practice standards. In response to this need for guidance, the Neurocritical Care Society set out to develop and evidence-based guideline using GRADE to safely reduce VTE and its associated complications.

Coagulation during elective neurosurgery with hydroxyethyl starch fluid therapy: an observational study with thromboelastometry, fibrinogen and factor XIII

BACKGROUND

Several studies have described hypercoagulability in neurosurgery with craniotomy for brain tumor resection. In this study, hydroxyethyl starch (HES) 130/0.42 was used for hemodynamic stabilization and initial blood loss replacement. HES can induce coagulopathy with thromboelastographic signs of decreased clot strength. The aim of this study was to prospectively describe perioperative changes in coagulation during elective craniotomy for brain tumor resection with the present fluid regimen.

METHODS

Forty patients were included. Perioperative whole-blood samples were collected for EXTEM and FIBTEM assays on rotational thromboelastometry (ROTEM) and plasma fibrinogen analysis immediately before surgery, after 1 L of HES infusion, at the end of surgery and in the morning after surgery. Factor (F)XIII activity, thrombin-antithrombin complex (TAT) and plasmin-α2-antiplasmin complex (PAP) were analysed in the 25 patients receiving ≥1 L of HES.

RESULTS

Most patients (37 of 40) received HES infusion (0.5-2 L) during surgery. Preoperative ROTEM clot formation/structure, plasma fibrinogen and FXIII levels were generally within normal range but approached a hypocoagulant state during and at end of surgery. ROTEM variables and fibrinogen levels, but not FXIII, returned to baseline levels in the morning after surgery. Low perioperative fibrinogen levels were common. TAT levels were increased during and after surgery. PAP levels mostly remained within the reference ranges, not indicating excessive fibrinolysis. There were no differences in ROTEM results and fibrinogen levels in patients receiving <1 L HES and ≥1 L HES.

CONCLUSIONS

Only the increased TAT levels indicated an intra- and postoperative activation of coagulation. On the contrary, all other variables deteriorated towards hypocoagulation but were mainly normalized in the morning after surgery. Although this might be an effect of colloid-induced coagulopathy, we found no dose-dependent effect of HES. The unactivated fibrinolysis indicates that prophylactic use of tranexamic acid does not seem warranted under normal circumstances in elective neurosurgery. Individualized fluid therapy and coagulation factor substitution is of interest for future studies.

Silent pulmonary thromboembolism in neurosurgery patients: Report of 2 cases and literature review

BACKGROUND

The requirement of postoperative bedridden and immobilization renders neurosurgical patients with higher risk of deep vein thrombosis (DVT), then more vulnerable for pulmonary thromboembolism (PTE). But silent pulmonary thromboembolism (SPTE) can be the very early stage of any typical form of PTE, its diagnosis and management is therefore critical in neurosurgical departments. However, to date, perioperative SPTE has not been attached with enough attention.

METHODS

Here, we report 2 cases of perioperative SPTE in the Department of Neurosurgery, Peking Union Medical College Hospital, Beijing, China. Clinical data of 2 cases was collected and analyzed. Both patients were screened by quantitative D-dimer assay and lower limbs ultrasonography, while diagnoses were made according to computed tomographic pulmonary angiography (CTPA). Therapeutic medications include heparin, low molecular weight heparin, followed by long-term anticoagulation with oral warfarin. Both cases showed significantly elevated D-dimer before and after onset of SPTE. But in 1 case, ultrasonography reported negative venous thromboembolism. CTPA confirmed all diagnosis of SPTE. Repeated CTPA after anticoagulant therapy identified therapeutic efficacy. And during the follow-up period of 5 or 6 years, both patients acquired full recovery without clinical complications.

RESULTS

Significant decline of D-dimer was observed after the comprehensive management of SPTE (case 1: preop vs postop 573 vs 50 μg/L; case 2: preop vs postop 246 vs 50 μg/L). Ultrasonography was used for suspicious of DVT, while CTPA was used for confirming SPTE diagnosis.

CONCLUSION

Clinicians should be aware of the importance of early recognition of SPTE. Effective management of risk factors of hyper-coagulation state should be the key to prophylaxis. And routine monitor of D-dimer as well as regular check of lower limbs ultrasonography should be standardized and included in guidelines of neurosurgical patient management.

Safety of early pharmacological thromboprophylaxis after subarachnoid hemorrhage

OBJECTIVE

The recent guidelines on management of aneurysmal subarachnoid hemorrhage (aSAH) advise pharmacological thromboprophylaxis (PTP) after aneurysm obliteration. However, no study has addressed the safety of PTP in the aSAH population. Therefore, the aim of this study was to assess the safety of early PTP after aSAH.

METHODS

Retrospective cohort of aSAH patients admitted between January 2012 and June 2013 in a single high-volume aSAH center. Traumatic SAH and perimesencephalic hemorrhage patients were excluded. Patients were grouped according to PTP timing: early PTP group (PTP within 24 hours of aneurysm treatment), and delayed PTP group (PTP started > 24 hours).

RESULTS

A total of 174 SAH patients (mean age 56.3±12.5 years) were admitted during the study period. Thirty-nine patients (22%) did not receive PTP, whereas 135 patients (78%) received PTP after aneurysm treatment or negative angiography. Among the patients who received PTP, 65 (48%) had an external ventricular drain. Twenty-eight patients (21%) received early PTP, and 107 (79%) received delayed PTP. No patient in the early treatment group and three patients in the delayed PTP group developed an intracerebral hemorrhagic complication. Two required neurosurgical intervention and one died. These three patients were on concomitant PTP and dual antiplatelet therapy.

CONCLUSIONS

The initiation of PTP within 24 hours may be safe after the treatment of a ruptured aneurysm or in angiogram-negative SAH patients with diffuse aneurysmal hemorrhage pattern. We suggest caution with concomitant use of PTP and dual antiplatelet agents, because it possibly increases the risk for intracerebral hemorrhage.