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.

Neuraxial Techniques for Parturients with Thromboprophylaxis or Thrombocytopenia.

Pharmacologic thromboprophylaxis from venous thromboembolism (VTE) and thrombocytopenia in pregnancy results in conditions that may preclude the use of neuraxial anesthesia due to a perceived risk of spinal/epidural hematoma. Spinal epidural hematoma is a recognized complication in patients who are hypocoagulable and may lead patients to undergo general anesthesia for delivery or other procedures, which carries numerous complications in obstetric care. A robust understanding of maternal physiologic changes in coagulation status, review of consensus statements, and safety bundles may help to maximize the use of neuraxial anesthesia in obstetric patients who might otherwise be denied these anesthetic techniques.

Epidural hemostasis by autologous fat graft in minimally invasive surgery for lumbar spinal stenosis: In vivo experimental study.

BACKGROUND: Epidural hemostasis needs to use small, adapted material in minimally invasive surgery, including bilateral decompression via a unilateral approach for lumbar spinal stenosis. Most surgeons avoid external material for hemostasis because of possible neural tissue damage or complications. We compared epidural hemostasis in minimally invasive surgery by fat graft versus gelatin sponge. METHODS: The design was a prospective randomized controlled in-vivo human experimental study. The 24 levels operated on for lumbar spinal stenosis were evaluated in two groups: Group A (control group: gelatin sponge) and Group B (experimental group: fat graft). International Normalized Ratio and Prothrombin Time were assessed preoperatively. Number of cotton hemostats and systolic and diastolic blood pressure were assessed intraoperatively. Epidural hemorrhage area, spinal cord size and ratio of epidural hemorrhage area to spinal cord size were evaluated on early postoperative lumbar MRI. RESULTS: Mean epidural hemorrhage area in groups A and B was respectively 1.3±0.5 and 1.2±0.6cm2, and mean spinal cord size 1.2±0.6 and 1.8±0.6cm2 on early postoperative axial lumbar MRI. The two groups did not significantly differ in ratio of epidural hemorrhage/spinal cord size or number of intraoperative hemostats (P=0.36, and P=0.71). CONCLUSIONS: The autologous fat graft ensured sufficient and safe epidural hemostasis without serious adverse events in minimally invasive spinal surgery, and is preferable as autologous tissue is easily and quickly harvested. The surgeon feels safe with this technique and does not need external hemostatic agents.

Protocatechuic acid improves functional recovery after spinal cord injury by attenuating blood-spinal cord barrier disruption and hemorrhage in rats.

After spinal cord injury (SCI), blood-spinal cord barrier (BSCB) disruption and hemorrhage lead to blood cell infiltration and progressive secondary injuries including inflammation. Inflammatory response is one of the major events resulting in apoptosis, scar formation and neuronal dysfunction after SCI. Here, we investigated whether protocatechuic acid (PCA), a natural phenolic compound, would attenuate BSCB disruption and hemorrhage, leading to functional improvement after SCI. After a moderate contusion injury at T9, PCA (50 mg/kg) was administrated via intraperitoneal injection immediately, 6 h, and 12 h after SCI, and the same dose of PCA once a day until 7 d after injury. Our data show that PCA inhibited apoptotic cell death of neurons and oligodendrocytes and improved functional recovery after injury. PCA also attenuated BSCB disruption and hemorrhage and reduced the infiltration of neutrophils and macrophages compared to vehicle control. Moreover, PCA inhibited the expression and activation of matrix metalloprotease-9, which is well known to disrupt BSCB after SCI. Furthermore, PCA treatment significantly inhibited the expression of sulfonylurea receptor 1 and transient receptor potential melastatin 4, which are known to mediate hemorrhage at an early stage after SCI. Consistent with these findings, the mRNA and protein expression of inflammatory mediators such as tumor necrosis factor alpha, interleukin 1 beta, cyclooxygenase-2, inducible nitric oxide synthase, and chemokines was significantly alleviated by PCA treatment. Thus, our results suggest that PCA improved functional recovery after SCI in part by inhibiting BSCB disruption and hemorrhage through the down-regulation of sulfonylurea receptor 1/transient receptor potential melastatin 4 and matrix metalloprotease-9.

Nerve root injection cancellations because of incomplete anticoagulation management.

BACKGROUND: Computed tomography-guided steroid injection is a well-recognized, conservative treatment of localized spinal pain as a result of facet arthropathy and radiculopathy secondary to nerve root compression. An extremely rare complication is the development of an epidural haematoma with potential to cause permanent neurological damage, so anticoagulation at the time of procedure is contraindicated. Routinely injections are performed as an outpatient requiring the referring physician to implement a peri-procedural anticoagulation plan. Anecdotal experience suggested that cancellations were occurring as patients remained on anticoagulation at the time of their appointment. The authors therefore assessed the existing service against expected standards to identify the causes of cancellations and find ways to improve the service. AIMS: This audit aimed to identify the incidence of cancelled computed tomography-guided nerve root injections secondary to incorrect peri-procedural anticoagulation management, develop an intervention to help reduce the incidence of cancellations and then re-audit to assess the effect of the intervention. METHODS: The audit standard was that 100% of outpatients attending for computed tomography-guided nerve root and facet injections should have an appropriate anticoagulation plan implemented. Baseline data collection took place prospectively between 1 September and 30 November 2016. The study population was elective computed tomography-guided spinal nerve root and facet injections scheduled on the radiology information system at the authors' trust. Descriptive analysis was completed. The intervention involved a revised electronic request form being implemented with new compulsory fields concerning antiplatelets and anticoagulants. Re-audit post-intervention involved prospective data collection between 1 September and 30 November 2017 using the same methods. RESULTS: Baseline audit found that of three out of 55 (5%) patients had cancellations. On re-audit, there were 0 cancellations out of 93 patients. CONCLUSIONS: The new request form prevented 5% of patients referred for computed tomography-guided nerve root injection being cancelled because of incorrect anticoagulation management. Extrapolated over the year the potential savings through preventing lost activity are £3445.56.

A systematic review and meta-analysis of wound drains in non-instrumented lumbar decompression surgery.

Wound drains are routinely used in lumbar decompressive surgery (LDS). However, it remains unclear whether this practice helps to prevent symptomatic epidural hematoma formation and associated complications, particularly following non-instrumented procedures. A systematic review and meta-analysis was therefore completed to critically appraise the literature. The search protocol was conducted using the Ovid MEDLINE, EMBASE, Scopus, Cochrane Library, and Google Scholar databases. Articles meeting the following criteria were included: (i) examined patients undergoing LDS; (ii) included cases receiving post-operative wound drains; (iii) detailed adverse outcomes including symptomatic epidural hematomas or wound infection; and (iv) were published in English in a peer-reviewed journal. Pooled risk differences (RD) for adverse outcomes were calculated using Comprehensive Meta-Analysis software. Three Level 1b prospective randomized studies and five Level 2b retrospective cohort studies were included, from which 5327 cases were identified as having received a surgical drain and 773 were identified as having received no drainage following non-instrumented LDS. There was no difference between groups in the risk of symptomatic epidural hematoma (RD = 0.02; 95% CI -0.02 - 0.06, p = 0.28) or post-operative infection (RD = 0.00; 95% CI -0.01 - 0.01, p = 0.91). In conclusion, symptomatic epidural hematomas and infection are rare following non-instrumented LDS, with incidence rates unaffected by the routine use of wound drainage.

[Research progress on early diagnosis, reasonable prevention and treatment of symptomatic spinal epidural hematoma following spinal surgery].

Symptomatic spinal epidural hematoma (SSEH) following spinal surgery is rare but one of the serious complications. SSEH can leave devastating neurological consequences if missing the optimal timing for treatment. The early diagnosis of SSEH is critical to the neurologic recovery, and MRI examination can help to check the location and the scope of the hematoma and provide imaging information for surgical operation. The risk factors of SSEH can be divided into preoperative factors, intraoperative factors and postoperative factors. The occurrence of SSEH can be minimized by controlling the risk factors, exact hemostasis and reasonable perioperative management. Patients with mild paralysis can choose conservative treatment, while patients with severe or progressive nerve injury (manual muscle testing <3) and unendurable nerve root pain should choose to clean the hematoma and decompress the nerve as soon as possible.

Causes and preventive measures of symptomatic spinal epidural haematoma after spinal surgery.

STUDY DESIGN: This was a retrospective study to evaluate clinical characteristics of patients who developed symptomatic spinal epidural haematoma (SSEH) after spinal surgery. OBJECTIVE: The objective was to determine clinical parameters associated with the development of SSEH after spinal surgery, and to discuss clinical management and possible preventive measures. Although the incidence rate of SSEH is low, the neurological sequelae are devastating. There are limited reports which identify risk factors for SSEH because of the rarity of the condition. METHODS: The 4,457 cases of spine operations performed in two medical centres were reviewed. Eleven of the cases developed postoperative spinal epidural haematomas, causing neurologic deterioration. The clinical manifestations of these 11 cases were described, and factors associated with the recovery of neurologic function were evaluated. RESULTS: The causes of SSEH following spinal surgery included inadequate drainage (9 cases), administration of anticoagulants (6 cases) and complicated coagulation disorders (1 case). The main clinical manifestation was progressive neurological deterioration in the innervated area. Seven cases underwent MRI examination and compressions of dural sac and spinal cord were observed. High pressure haematomas were found in eight cases during haematoma evacuation. Statistical analyses showed that patients with mild nerve injury at the initial stage were associated with better recovery (P<0.05). Patients who recovered completely had shorter symptom duration on average. CONCLUSIONS: Post-operative bleeding in the wound and inadequate drainage are the primary causes of SSEH. The severity of neurologic injury before haematoma evacuation was associated with the treatment outcome; therefore, it is important to have early diagnosis of SSEH to prevent progression of the neurologic injury.

Innovative Technique for the Placement of the Drainage Tube for Microendoscopic Spinal Decompression.

STUDY DESIGN: A technical note and retrospective study. OBJECTIVES: The objectives were to describe a new method of drainage tube placement during microendoscopic spinal decompression, and compare the positioning and fluid discharge obtained with this method and the conventional method. SUMMARY OF BACKGROUND DATA: To prevent postoperative epidural hematoma after microendoscopic decompression, a drainage tube must be placed in a suitable location. However, the narrow operative field makes precise control of the position of the tube technically difficult. We developed a method to reliably place the tube in the desired location. MATERIALS AND METHODS: We use a Deschamps aneurysm needle with a slightly curved tip, which we call a drain passer. With the microendoscope in position, the drain passer, with a silk thread passed through the eye at the needle tip, is inserted percutaneously into the endoscopic field of view. The drainage tube is passed through the loop of silk thread protruding from the inside of the tubular retractor, and the thread is pulled to the outside, guiding the end of the drainage tube into the wound. This method was used in 23 cases at 44 intervertebral levels (drain passer group), and the conventional method in 20 cases at 32 intervertebral levels (conventional group). Postoperative plain radiographs were taken, and the amount of fluid discharge at postoperative hour 24 was measured. RESULTS: Drainage tube positioning was favorable at 43 intervertebral levels (97.7%) in the drain passer group and 26 intervertebral levels (81.3%) in the conventional group. Mean fluid discharge was 58.4±32.2 g in the drain passer group and 38.4±23.0 g in the conventional group. Positioning was significantly better and fluid discharge was significantly greater in the drain passer group. CONCLUSION: The results indicate that this method is a useful drainage tube placement technique for preventing postoperative epidural hematoma.

Why Cannot Suction Drains Prevent Postoperative Spinal Epidural Hematoma?

BACKGROUND: Postoperative spinal epidural hematoma (POSEH) is different from spontaneous or post-spinal procedure hematoma because of the application of suction drains. However, it appeared that suction drains were not effective for prevention of POSEH in previous studies. The purpose of this study was to test our hypothesis that POSEH can be caused by hypercoagulability. METHODS: This was an experimental study. One hundred fifty milliliters of blood was donated from each of the 12 consecutive patients who underwent spine surgery and infused into 3 saline bags of 50 mL each. One of the 3 bags in each set contained 5,000 units of thrombin. All of them were connected to 120 ± 30 mmHg vacuum suctions: drainage was started 8 minutes after connection to the vacuum system for 12 normal blood bags (BV8) and 12 thrombin-containing blood bags (TBV8) and 15 minutes after connection for the remaining 12 normal blood bags (BV15). The amount of initial and remaining hematoma at 20 minutes, 120 minutes, and 24 hours after vacuum application were measured by their weight (g). The primary endpoint was the difference between BV8 and TBV8. The secondary end point was the difference between BV8 and BV15. RESULTS: The remaining hematoma in TBV8 was significantly greater than that in BV8 at all measurement points: 46.3 ± 12.4 vs. 17.0 ± 1.3 (p = 0.000) at 20 minutes; 33.0 ± 8.2 vs. 16.3 ± 1.2 (p = 0.000) at 120 minutes; and 26.1 ± 4.0 vs. 15.8 ± 1.6 (p = 0.000) at 24 hours after vacuum application. The remaining hematoma of BV15 was significantly greater than that of BV8 at all measurement points: 30.0 ± 12.0 vs. 17.0 ± 1.3 (p = 0.002) at 20 minutes; 24.2 ± 7.6 vs. 16.3 ± 1.2 at 120 minutes (p = 0.002); and 22.2 ± 6.6 vs. 15.8 ± 1.6 (p = 0.004) at 24 hours after vacuum application. CONCLUSIONS: With a suction drain in place, the amount of remaining hematoma could be affected by coagulability. Thrombin-containing local hemostatics and the length of time elapsed before the commencement of suction resulted in hypercoagulability, indicating these two factors could be causes of POSEH.

Wound drains in non-complex lumbar surgery: a systematic review.

AIMS: Our aim was to perform a systematic review of the literature to assess the incidence of post-operative epidural haematomas and wound infections after one-, or two-level, non-complex, lumbar surgery for degenerative disease in patients with, or without post-operative wound drainage. PATIENTS AND METHODS: Studies were identified from PubMed and EMBASE, up to and including 27 August 2015, for papers describing one- or two-level lumbar discectomy and/or laminectomy for degenerative disease in adults which reported any form of subcutaneous or subfascial drainage. RESULTS: Eight papers describing 1333 patients were included. Clinically relevant post-operative epidural haematomas occurred in two (0.15%), and wound infections in ten (0.75%) patients. Epidural haematomas occurred in two (0.47%) patients who had wound drainage (n = 423) and in none of those without wound drainage (n = 910). Wound infections occurred in two (0.47%) patients with wound drainage and in eight (0.88%) patients without wound drainage. CONCLUSION: These data suggest that the routine use of a wound drain in non-complex lumbar surgery does not prevent post-operative epidural haematomas and that the absence of a drain does not lead to a significant change in the incidence of wound infection. Cite this article: Bone Joint J 2016;98-B:984-9.

Urokinase-Treated Antithrombogenic Drains and Optimized Drain Placement in Endoscopic Lumbar Decompressive Surgery.

Background Spinal epidural hematoma (SEH) frequently occurs after microendoscopic decompressive laminotomy (MEDL), and a drain may not be functioning sufficiently. Objective To reduce the incidence of SEH after MEDL. Methods A urokinase-treated antithrombogenic drain, which is available only with a large diameter, was reduced in diameter and used after MEDL. Magnetic resonance imaging (MRI) and computed tomography (CT) were performed 36 to 48 hours after surgery. The size of the SEH was measured by MRI, and the location of the drain tip was assessed by CT scan. After imaging, the drain was removed. Results Use of the urokinase-treated antithrombogenic drain reduced the incidence of SEH. However, the drain was not adequately placed in many cases, limiting the effect of the drainage. When the urokinase-treated antithrombogenic drain was placed contralaterally to the approach side using an unsheathed endoscope, the incidence of SEH was further reduced. Conclusions The urokinase-treated antithrombogenic drain prevented thrombus-related drain obstruction. In addition, unsheathed endoscopic contralateral placement of the drain was effective for SEH prevention.

The Use of Closed Suction Drainage in Lumbar Spinal Surgery: Is It Really Necessary?

BACKGROUND: Closed wound suction drainage after spine surgery is commonly used in clinical practice. However, no consensus has been reached for using drainage versus nondrainage after lumbar spinal surgery until now. OBJECTIVE: The purpose of this study was to determine the clinical outcomes of using closed suction drainage versus nondrainage after lumbar spinal surgery. METHODS: We conducted a systematic review and meta-analysis to identify relevant studies from PubMed, MEDLINE, EMBASE, Cochrane Library, and Google scholar up to September 2015. All randomized, quasi-randomized, and controlled clinical studies, which compared the clinical outcomes of using closed suction drainage versus nondrainage in patients who underwent lumbar spinal surgery, were included. Data extraction and quality assessment were according to Cochrane Collaboration guidelines. RESULTS: Five studies involving 1295 patients were included in this meta-analysis. By pooling the clinical outcomes, there were no significant differences between patients with drainage and nondrainage in terms of the incidence of wound infection (odds ratio [OR], 1.48; 95% confidence interval [CI], 0.47-4.71; P = 0.50), wound hematoma (OR, 0.45; 95% CI, 0.01-29.31, P = 0.71), and reoperation (OR, 1.36; 95% CI, 0.22-8.27; P = 0.74). Drainage after lumbar surgery was associated with more blood loss and significantly greater blood transfusions (OR, 3.68; 95% CI, 1.80-7.54; P < 0.01) compared with nondrainage. However, more patients contracted postoperative fever in the nondrainage group than did those in drainage group. CONCLUSIONS: Based on this systematic review and meta-analysis, there is insufficient evidence to suggest routine use of prophylactic closed suction drainage after lumbar spinal surgery. However, a decision to use or not use drainage should be individualized for each patient because many factors affect the outcomes.

Can We Prevent a Postoperative Spinal Epidural Hematoma by Using Larger Diameter Suction Drains?

BACKGROUND: Epidural hematoma is a rare but serious complication. According to previous studies, it is not prevented by suction drains. This study evaluated the following alternative hypothesis: the larger the diameter of a suction drain, the less the remaining epidural hematoma after spinal surgery. METHODS: This was a randomized prospective study. Patients who underwent posterior lumbar decompression and instrumented fusion were divided into two groups: the large drain (LD, 2.8-mm-diameter tube) and small drain (SD, 1.6-mm-diameter tube) groups according to the diameter of the suction drains. All patients were consecutive and allocated alternately according to the date of operations. Suction drains were removed on day 3 and magnetic resonance imaging was performed on day 7 postoperatively. The size of remaining hematomas was measured by the degree of thecal sac compression in cross section using the following 4-point numeric scale: G1, less than one quarter; G2, between one quarter and half; G3, more than half; and G4, more than subtotal obstruction. RESULTS: There were 39 patients with LDs and 38 with SDs. They did not differ significantly in terms of sex, number of fusion segments, revision or not, antiplatelet medication, intraoperative injection of tranexamic acid. However, patient age differed significantly between the two groups (LD, 63.3 years and < SD, 68.6 years; p = 0.007). The two groups did not differ significantly in terms of prothrombin time, activated partial thromboplastin time, platelet number, blood loss, or operation duration. However, platelet function analysis exhibited a significant difference (LD, 164.7 seconds and < SD, 222.3 seconds; p = 0.002). The two blinded readers showed high consistency (Kappa value = 0.740; p = 0.000). The results of reader 1 were as follows: LD and SD had 21 and 21 cases of G1, 9 and 11 cases of G2, 6 and 6 cases of G3, and 3 and 0 cases of G4, respectively. The results of reader 2 were as follows: LD and SD had 22 and 23 cases of G1, 7 and 9 cases of G2, 7 and 6 cases of G3, and 3 and 0 cases of G4, respectively. There was no difference between the two groups (reader 1, p = 0.636; reader 2, p = 0.466). CONCLUSIONS: The alternative hypothesis was rejected. Therefore, postoperative spinal epidural hematoma would not be prevented by LD.

[Thromboprophylaxis and platelet aggregation inhibitors in spinal surgery: perioperative management]. / Thromboseprophylaxe und Aggregationshemmer in der Wirbelsäulenchirurgie: perioperative Management.

BACKGROUND: The perioperative use of anticoagulants (AC) and platelet aggregation inhibitors (PAI) in the field of spinal surgery suggests an increased rate of epidural bleeding. However, evidence is lacking and these medications are most often indispensable in the prevention of thromboembolic complications. Comprehensive recommendations for the correct use of AC and PAI are lacking. OBJECTIVE: The aim of this study was an analysis of the current situation with regards to the use of AC and PAI in spinal surgery and development of new recommendations. MATERIAL AND METHODS: Two independent surveys on the perioperative use of AC and PAI were obtained from centers for spinal surgery in Germany. The study obtained information on the perioperative use of AC and PAI, risk assessment of thromboembolic and hemorrhagic events as well as on the type and extent of the substance groups used. RESULTS: Almost the entire patient collective (98%) received perioperative low molecular weight heparin. In 64% the medical prophylaxis was started before surgery and in 36% after surgery. The period of prophylaxis was determined arbitrarily. Approximately 40% of interviewees employed paravertebral infiltration and 19% injected into the epidural space in patients on PAI medication. Open spinal canal surgery was performed in 30% of PAI medicated patients and closed spinal canal surgery was executed in 40%. The risk assessment of PAI differed significantly between aspirin and receptor blocker medication as well as dual administration of PAI. DISCUSSION: The use of AC and PAI in spinal surgery in Germany is very heterogeneous and large deviations from the guidelines frequently occurred. Therefore, there is a strong need for further studies to accurately assess the perioperative use of AC and PAI and to formulate precise recommendations.

New oral anticoagulants: a practical guide on prescription, laboratory testing and peri-procedural/bleeding management. Australasian Society of Thrombosis and Haemostasis.

New oral anticoagulants (NOAC) are becoming available as alternatives to warfarin to prevent systemic embolism in patients with non-valvular atrial fibrillation and for the treatment and prevention of venous thromboembolism. An in-depth understanding of their pharmacology is invaluable for appropriate prescription and optimal management of patients receiving these drugs should unexpected complications (such as bleeding) occur, or the patient requires urgent surgery. The Australasian Society of Thrombosis and Haemostasis has set out to inform physicians on the use of the different NOAC based on current available evidence focusing on: (i) selection of the most suitable patient groups to receive NOAC, (ii) laboratory measurements of NOAC in appropriate circumstances and (iii) management of patients taking NOAC in the perioperative period, and strategies to manage bleeding complications or 'reverse' the anticoagulant effects for urgent invasive procedures.

Reconsidering the switch from low-molecular-weight heparin to unfractionated heparin during pregnancy.

Venous thromboembolic disease accounts for 9% of all maternal deaths in the United States. In patients at risk for thrombosis, common practice is to start prophylactic doses of low-molecular-weight heparin and transition to unfractionated heparin during the third trimester, with the perception that administration of neuraxial anesthesia will be safer while on unfractionated heparin, as spinal/epidural hematomas have been associated with recent use of low-molecular-weight heparin. In patients receiving prophylactic doses of unfractionated heparin, neuraxial anesthesia may be placed, provided the dose used is 5,000 units twice a day. The American Society of Regional Anesthesia and Pain Medicine guidelines recognize that the safety of neuraxial anesthesia in patients receiving more than 10,000 units per day or more than 2 doses per day is unknown, limiting the theoretical benefit of unfractionated heparin at doses higher than 5,000 units twice a day.

Practical management of new oral anticoagulants after total hip or total knee arthroplasty.

Within the past 5 years, the oral anticoagulants rivaroxaban, apixaban, and dabigatran etexilate have been approved for the prevention of venous thromboembolism in adult patients after elective hip or knee arthroplasty in the European Union and many other countries worldwide. These agents differ from the previously available anticoagulants because they selectively and directly inhibit a single factor in the coagulation cascade-rivaroxaban and apixaban inhibit Factor Xa, and dabigatran inhibits Factor IIa (thrombin)-potentially enhancing the predictability of their anticoagulant effect. Currently, although some guidelines provide recommendations for the use of rivaroxaban, dabigatran etexilate, and apixaban in clinical practice, there are still questions regarding the optimal practical management of patients receiving these agents. This article briefly reviews the practical limitations associated with conventional anticoagulants, discusses potential issues with the practical management of the newer oral anticoagulants, and provides clinical experience from a single institution where rivaroxaban and dabigatran etexilate have been used within their approved indications.

[Analysis of epidural hematoma formative reason and its preventive measure after anterior cervical operation].

OBJECTIVE: To explore the risk factors,preventive measure of epidural hematoma after anterior cervical operation. METHODS: From June 2005 and December 2012, 1,452 patients underwent anterior cervical operation in our hospital. Epidural hematoma occurred in 5 cases after operation and the incidence rate was 0.34%. There were 4 males and 1 female with an average age of 46.4 years (ranged, 33 to 55); 3 cases with cervical myelopathy, 1 case with cervical myelopathy and C5 vertebral angeioma, 1 case with ossification of cervical posterior longitudinal ligament. The occurred time,main clinical situation,duration of symptoms,operative management of epidural hematoma were analyzed. RESULTS: Five patients with epidural hematoma occurred within 24 h; the average interval between onset of symptoms and surgery was 4 h (ranged, 2 to 7). Operative treatment was accomplished in 5 cases by exploration and hematoma evacuation. There was significant improvement in all patients after reoperation. Epidural hematoma occurred again in one patient at 5 h after hematoma evacuation, and reoperation were performed to treat it. All patients were followed up from 6 to18 months with an average of 13.8 months. No recurrence was found. CONCLUSION: Intensive care in 24 h postoperatively is important because of epidural hematoma often occurs in this period,especialy in the period of 6-8 h postoperativey. Clinical findings and MRI can early diagnose epidural hematoma and help treatment. Once it is identified and surgical evacuation would be performed on time.

Safety of thromboembolic chemoprophylaxis in spinal trauma patients requiring surgical stabilization.

STUDY DESIGN: Retrospective review. OBJECTIVE: To determine the incidence of thromboembolic events, bleeding complications such as epidural hematomas, and wound complications in patients with spinal trauma requiring surgical stabilization. SUMMARY OF BACKGROUND DATA: Literature addressing the safety and efficacy of chemoprophylactic agents in postoperative patients with spinal trauma is sparse. As a result, significant variability exists regarding administration of thromboembolic chemoprophylaxis in this population. The risk of bleeding complications is particularly concerning. METHODS: Patients with spinal trauma who underwent surgical stabilization in 2009 and 2010 at a single level 1 trauma center were retrospectively reviewed. Exclusion criteria included patients who underwent solely decompressive procedures, noninstrumented fusions, kyphoplasty, or had incomplete medical records. Patients who received chemoprophylaxis were compared with patients who did not. Demographical information and injury data were collected. Primary outcome measures were prevalence of thromboembolic events, epidural hematomas, and persistent wound drainage requiring irrigation and debridement. RESULTS: Two hundred twenty-seven of 373 patients were included (56 in the untreated group, 171 in the treated group). Eight patients in the untreated group (14.3%) and 12 patients in the treated group (7%) developed postoperative thromboembolism (P = 0.096). There was 1 pulmonary embolism in the untreated group (1.8%), and 4 pulmonary embolisms in the treated group (2.3%). Surgical irrigation and debridement for wound drainage was required for 1.8% of patients in the untreated group and for 5.3% of patients in the treated group. No epidural hematomas were noted in either group. The treated group had more spinal levels fused (P = 0.46), higher injury severity scores (0.001), and longer hospitalizations (0.018). Patients who developed postoperative thromboembolism had significantly higher body mass indexes (P = 0.01), injury severity scores (0.001), number of spinal levels fused (P = 0.004), incidence of neurological deficits (0.001), and longer hospitalizations (0.16) compared with those who did not. CONCLUSION: The use of chemoprophylaxis appears to be safe in at-risk patients in the immediate postoperative period after spinal trauma surgery. No epidural hematomas occurred, and the risk of wound drainage is small. Body mass index, injury severity score, presence of neurological deficits, and number of spinal levels fused should be considered when determining which patients should receive chemoprophylaxis after surgical stabilization.