Hemostatic and hemorrhagic problems in neurosurgical patients

The rate of postoperative hematoma following risk-adapted cessation of oral anticoagulation in patients undergoing endoscopic endonasal surgery for pituitary adenomas

BACKGROUND

This study describes the management of patients on oral anticoagulation (OAC) undergoing endoscopic endonasal transsphenoidal surgery (EETS) and analyzes the risk of postoperative hematoma and epistaxis following treatment of pituitary adenoma (PA).

METHODS

Patients with OAC prior to EETS for PA were analyzed in a single center retrospective case series of consecutive patients with PA, who were treated between December 2008 and July 2022. Patient data (age, sex, clinical, endocrinology, tumor histology) were entered into a SPSS® database. The rate of postoperative hemorrhage (intracranial and epistaxis) and other perioperative complications were assessed.

RESULTS

Of 305 patients, 20 patients were on OAC prior to EETS for PA. Indications included non-valvular atrial fibrillation (AF) in 10 patients and previous venous thromboembolic event (VTE) in 8 patients, in 2 patients had overlapping indications. Twelve patients on direct oral anticoagulants (DOAC) paused medication 1-3 days (43.6 ± 23.6 h) before surgery, while phenprocoumon was paused 234 ± 123.55 h (min 6, max 22 days) before surgery. Baseline characteristics such as age, sex, tumor growth direction, tumor volume, and largest diameter showed no significant differences. No significant increase in postoperative hemorrhage was observed in patients with OAC compared to those without. One patient on apixaban paused 48 h before surgery experienced postoperative epistaxis. Among patients without OAC, one experienced intracranial hemorrhage and seven experienced epistaxis.

CONCLUSION

Patients with OAC prior to EETS for PA have no increased risk for postoperative hematoma when OAC is paused based on individual risk assessment and recent general recommendations.

Patient with congenital factor VII deficiency undergoing brain tumor neurosurgery successfully treated with recombinant factor VIIa and fresh frozen plasma: A case report and literature review

RATIONALE

Congenital factor VII deficiency is the most common among rare bleeding disorders, characterized by spontaneous or traumatic bleeding. The clinical manifestation is heterogeneous, ranging from asymptomatic phenotype to life-threatening hemorrhages. Intracranial hemorrhage is a common complication of brain tumor neurosurgery, which significantly challenges the perioperative management of patients with hemostatic defects.

PATIENT CONCERNS

This report presented a 55-year-old man with congenital factor VII deficiency, who had no history of hemorrhage or family history. He underwent a craniotomy for the treatment of papillary craniopharyngioma.

DIAGNOSES

The patient was diagnosed as papillary craniopharyngioma, factor VII deficiency, and atrial fibrillation.

INTERVENTIONS

To prevent bleeding, a total of 8 doses of recombinant activated factor VII and 1 dose of fresh frozen plasma were administered as the perioperative replacement therapy. This scheme was guided by a pharmacodynamic evaluation, laboratory tests, and imaging examinations.

OUTCOMES

No excessive surgical bleeding was observed during the 22-day treatment. The patient was found to have compound heterozygous mutations, Ala304Thr (c.910G > A) and IVS5-2A > G (c.572-2A > G), in the F7 gene.

LESSONS

This is the first reported case in which surgical hemorrhage secondary to brain tumor resection was successfully controlled in the presence of congenital factor VII deficiency. Perioperative coagulation state, hemostasis, and thrombosis events should be closely observed, and the interval and dosage of recombinant factor VIIa should be adjusted accordingly.

Evaluation of the association of factor XIII at hospital arrival and outcomes in a cohort of severely injured patients

BACKGROUND

Severe traumatic bleeding depletes coagulation factor XIII (FXIII) and fibrinogen. However, the role of FXIII level in bleeding-related outcomes is unknown.

OBJECTIVES

To evaluate the association between FXIII levels at hospital arrival and critical administration threshold (≥3 red blood cell units in 1 hour within the first 24 hours), bleeding-related outcomes, death, and baseline characteristics.

METHODS

A retrospective cohort study was conducted in severely injured adult patients (Injury Severity Score of ≥22 or ≥2 red blood cell units transfused in 24 hours) admitted to a level 1 trauma center. Clinical and laboratory data were collected. Baseline FXIII antigen levels were measured in banked patient plasma. Multivariable logistic and linear regression models were used to estimate the association between FXIII levels, outcomes, and baseline characteristics.

RESULTS

Three hundred sixty-four of 1730 subjects admitted during a 2-year period were analyzed. Median age was 44 years (IQR, 27-62 years), and median Injury Severity Score was 29 (IQR, 22-34). FXIII levels were not associated with critical administration threshold (odds ratio [OR], 1.06; 95% CI, 0.97-1.17) or death (OR, 0.98; 95% CI, 0.90-1.07). FXIII was associated with major bleeding (OR, 1.10; 95% CI, 1.02-1.2) and massive transfusion (OR, 1.25; 95% CI, 1.08-1.44). Lower baseline FXIII levels were associated with arrival from a referring hospital (FXIII level, -0.07 U/mL; 95% CI, -0.11 to -0.03), hemoglobin (FXIII level, -0.05 U/mL; 95% CI, -0.07 to -0.03), fibrinogen level (FXIII level, -0.05 U/mL; 95% CI, -0.08 to -0.02), and platelet count (FXIII level, -0.02 U/mL; 95% CI, -0.04 to -0.008).

CONCLUSIONS

Baseline FXIII levels in severely injured patients were inconsistently associated with bleeding-related outcomes and mortality. However, their association with major bleeding warrants further investigation of the role of FXIII in massively transfused patients with trauma.

Development and validation of a prediction tool for intraoperative blood transfusion in brain tumor resection surgery: a retrospective analysis

Early identification of a patient with a high risk of blood transfusion during brain tumor resection surgery is difficult but critical for implementing preoperative blood-saving strategies. This study aims to develop and validate a machine learning prediction tool for intraoperative blood transfusion in brain tumor resection surgery. A total of 541 patients who underwent brain tumor resection surgery in our hospital from January 2019 to December 2021 were retrospectively enrolled in this study. We incorporated demographics, preoperative comorbidities, and laboratory risk factors. Features were selected using the least absolute shrinkage and selection operator (LASSO). Eight machine learning algorithms were benchmarked to identify the best model to predict intraoperative blood transfusion. The prediction tool was established based on the best algorithm and evaluated with discriminative ability. The data were randomly split into training and test groups at a ratio of 7:3. LASSO identified seven preoperative relevant factors in the training group: hemoglobin, diameter, prothrombin time, white blood cell count (WBC), age, physical status of the American Society of Anesthesiologists (ASA) classification, and heart function. Logistic regression, linear discriminant analysis, supporter vector machine, and ranger all performed better in the eight machine learning algorithms with classification errors of 0.185, 0.193, 0.199, and 0.196, respectively. A nomogram was then established, and the model showed a better discrimination ability [0.817, 95% CI (0.739, 0.895)] than hemoglobin [0.663, 95% CI (0.557, 0.770)] alone in the test group (P = 0.000). Hemoglobin, diameter, prothrombin time, WBC, age, ASA status, and heart function are risk factors of intraoperative blood transfusion in brain tumor resection surgery. The prediction tool established using the logistic regression algorithm showed a good discriminative ability than hemoglobin alone for predicting intraoperative blood transfusion in brain tumor resection surgery.

Management and risk of postoperative bleeding in patients with low-dose antiplatelet aspirin medication during endoscopic endonasal surgery for pituitary adenomas

BACKGROUND

To analyze the risk of postoperative bleeding following endoscopic endonasal transsphenoidal surgery (EETS) for treatment of pituitary adenomas (PA) in patients with short-term discontinuation of low-dose aspirin, if required for prevention of artherothrombotic disease (ATD).

METHODS

Patients with preoperative aspirin medication were identified in this single-center retrospective analysis of consecutive patients with PA, who underwent EETS between December 2008 and June 2022. Aspirin was discontinued perioperatively less than 2 days, > 2 and < 4 days, and > 4 and < 7 days according to the assumed risk of perioperative ATD. For those patients, the rate of postoperative bleeding, which required surgery, was compared to patients without aspirin.

RESULTS

Forty-five (14.8%) out of 304 patients underwent EETS with short-term perioperative aspirin discontinuation. Thirty-six (80%) patients discontinued aspirin < 2 days, 6 (13.3%) patients > 2 and < 4 days, and 3 patients (6.7%) > 4 but < 7 days. Postoperative bleeding rate was not increased in patients with short-term perioperative aspirin discontinuation. One patient (0.3%) without perioperative aspirin medication underwent revision surgery for treatment of postoperative hemorrhage with suprasellar extension. Eight patients (2.6%) had postoperative epistaxis (1 patient (0.3%) with short-term discontinuation and 7 patients (2.3%) without aspirin). Patients with perioperative aspirin were significantly older (68.3 ± 8.6 vs. 57.9 ± 14.1; p < 0.01) and had a significantly lower rate of hormonally active tumors (11.1% vs. 25.1%; p < 0.05) compared to patients without aspirin. No differences were found for tumor characteristics (tumor extension, tumor volume, largest diameter) between both groups.

CONCLUSION

Short-term discontinuation of low-dose aspirin was not associated with increased rate of postoperative bleeding in patients, who underwent EETS for treatment of PA.

Neurosurgical care for patients with high-grade gliomas during the coronavirus disease 2019 pandemic: Analysis of routine billing data of a German nationwide hospital network

Background

Little is known about delivery of neurosurgical care, complication rate and outcome of patients with high-grade glioma (HGG) during the coronavirus disease 2019 (Covid-19) pandemic.

Methods

This observational, retrospective cohort study analyzed routine administrative data of all patients admitted for neurosurgical treatment of an HGG within the Helios Hospital network in Germany. Data of the Covid-19 pandemic (March 1, 2020-May 31, 2022) were compared to the pre-pandemic period (January 1, 2016-February 29, 2020). Frequency of treatment and outcome (in-hospital mortality, length of hospital stay [LOHS], time in intensive care unit [TICU] and ventilation outside the operating room [OR]) were separately analyzed for patients with microsurgical resection (MR) or stereotactic biopsy (STBx).

Results

A total of 1763 patients underwent MR of an HGG (648 patients during the Covid-19 pandemic; 1115 patients in the pre-pandemic period). 513 patients underwent STBx (182 [pandemic]; 331 patients [pre-pandemic]). No significant differences were found for treatment frequency (MR: 2.95 patients/week [Covid-19 pandemic] vs. 3.04 patients/week [pre-pandemic], IRR 0.98, 95% CI: 0.89-1.07; STBx (1.82 [Covid-19 pandemic] vs. 1.86 [pre-pandemic], IRR 0.96, 95% CI: 0.80-1.16, P > .05). Rates of in-hospital mortality, infection, postoperative hemorrhage, cerebral ischemia and ventilation outside the OR were similar in both periods. Overall LOHS was significantly shorter for patients with MR and STBx during the Covid-19 pandemic.

Conclusions

The Covid-19 pandemic did not affect the frequency of neurosurgical treatment of patients with an HGG based on data of a large nationwide hospital network in Germany. LOHS was significantly shorter but quality of neurosurgical care and outcome was not altered during the Covid-19 pandemic.

Stratifying the risks of venous thromboembolism in the lateral skull base surgery using Caprini risk assessment model

PURPOSE

To analyze and stratify the possible risk factors of venous thromboembolism (VTE) in lateral skull base surgery (LSBS) using the Caprini risk assessment model.

METHODS

In a single center, a retrospective study was conducted with patients who underwent LSBS from June 2016 to August 2021. The clinical characteristics and blood chemistry tests were collected. The incidence of VTE within 30 days of surgery was recorded. The Caprini risk score was calculated to assess the postoperative VTE risk.

RESULTS

Among the 123 patients in this study, the VTE incidence within 30 postoperative days was 8.9%. The total Caprini risk score in VTE patients (5.6 ± 1.9 points) was significantly higher than that of non-VTE patients (4.6 ± 1.4 points; p = 0.028). The binary logistic regression showed the total Caprini score as the only independent indicator of postoperative VTE. The receiver operating characteristic curve analysis showed that the Caprini score at 6.5 points had low sensitivity (36.4%) but high specificity (91.1%), with the largest area under the curve being 0.659. The VTE rate was significantly higher in patients with a total Caprini score ≥ 7 points (28.6%) compared to those with a total Caprini score ≤ 6 points (7.3%; p = 0.022).

CONCLUSION

LSBS patients have a high risk of developing postoperative VTE. Patients with a Caprini score ≥ 7 points had a significantly higher risk of developing VTE after LSBS. The Caprini risk system was useful in assessing the VTE risk in LSBS. However, more data, calibration, and validation are necessary to establish an exclusive Caprini risk system for LSBS.

Variants of Oxidized Regenerated Cellulose and Their Distinct Effects on Neuronal Tissue

Based on oxidized regenerated cellulose (ORC), several hemostyptic materials, such as Tabotamp^®, Equicel^® and Equitamp^®, have been developed to approach challenging hemostasis in neurosurgery. The present study compares ORC that differ in terms of compositions and properties, regarding their structure, solubility, pH values and effects on neuronal tissue. Cytotoxicity was detected via DNA-binding fluorescence dye in Schwann cells, astrocytes, and neuronal cells. Additionally, organotypic hippocampal slice cultures (OHSC) were analyzed, using propidium iodide, hematoxylin-eosin, and isolectin B₄ staining to investigate the cellular damage, cytoarchitecture, and microglia activation. Whereas Equicel^® led to a neutral pH, Tabotamp^® (pH 2.8) and Equitamp^® (pH 4.8) caused a significant reduction of pH (p < 0.001). Equicel^® and Tabotamp^® increased cytotoxicity significantly in several cell lines (p < 0.01). On OHSC, Tabotamp^® and Equicel^® led to a stronger and deeper damage to the neuronal tissue than Equitamp^® or gauze (p < 0.01). Equicel^® increased strongly the number of microglia cells after 24 h (p < 0.001). Microglia cells were not detectable after Tabotamp^® treatment, presumably due to an artifact caused by strong pH reduction. In summary, our data imply the use of Equicel^®, Tabotamp^® or Equitamp^® for specific applications in distinct clinical settings depending on their localization or tissue properties.

Spontaneous and recurrent subdural haematoma in a patient with May-Hegglin anomaly

Both acute and chronic subdural haematomas typically occur following trauma. Non-traumatic causes are less common, but aetiologies include arteriovenous malformation, intracranial aneurysm rupture, tumour-associated haemorrhage and coagulopathies. May-Hegglin anomaly is an example of a coagulopathy, which is caused by a mutation in the gene encoding non-muscle myosin heavy chain 9 (MYH9) and therefore falls into a group of diseases referred to as MYH9-related diseases (MYH9-RD). The symptomology of MYH9-RD is often mild, and patients tend to experience epistaxis, gingival bleeding and bruising. Life-threatening haemorrhage rarely occurs. In this short report, we describe a patient with known May-Hegglin anomaly who presented with a potentially life-threatening, spontaneous subdural haematoma requiring surgery on two occasions. This is only the second such report in the literature, and the first of spontaneous and recurrent haemorrhage in association with May-Hegglin anomaly.

[Congenital coagulation disorders in neurosurgical patients. Literature review and case series]

Congenital coagulation disorders account about 1-2% and can pose a serious risk for neurosurgical patients. Indeed, coagulation management in these patients is essential to ensure normal hemostasis. Analysis of available literature devoted to this issue and case series of neurosurgical patients with congenital coagulation disorders. Literature data were obtained from the PubMed, Cochrane Library, Medline and Google Scholar databases for the period from 2019 to 2020. Over 200 reports devoted to our scientific issue were selected. We determined the key features of perioperative management of neurosurgical patients with congenital coagulation disorders. We have also analyzed 10 similar patients for the period from 2008 to 2020. Comprehensive analysis of anamnesis, adequate diagnosis, perioperative planning and multidisciplinary approach are essential for successful elective surgery in patients with congenital coagulation disorders.

First German Guideline on Diagnostics and Therapy of Clinically Non-Functioning Pituitary Tumors

Although non-functioning pituitary tumors are frequent, diagnostic and therapeutic concepts are not well standardized. We here present the first German multidisciplinary guideline on this topic. The single most important message is to manage the patients by a multidisciplinary team (consisting at least of an endocrinologist, a neurosurgeon, and a (neuro-) radiologist). The initial diagnostic work-up comprises a detailed characterization of both biochemical (focusing on hormonal excess or deficiency states) and morphological aspects (with magnetic resonance imaging of the sellar region). An ophthalmological examination is only needed in presence of symptoms or large tumors affecting the visual system. Asymptomatic, hormonally inactive tumors allow for a 'wait and scan' strategy. In contrast, surgical treatment by an experienced pituitary surgeon is standard of care in case of (impending) visual impairment. Therapeutic options for incompletely resected or recurrent tumors include re-operation, radiotherapy, and observation; the individual treatment plan should be developed multidisciplinary. Irrespective of the therapeutic approach applied, patients require long-term follow-up. Patient with larger pituitary tumors or former surgery/radiotherapy should be regularly counseled regarding potential symptoms of hormonal deficiency states.

Clinical management and outcome of adult patients with extracorporeal life support device-associated intracerebral hemorrhage-a neurocritical perspective and grading

Intracerebral hemorrhage (ICH) is a devastating complication in patients treated with extracorporeal membrane oxygenation (ECMO) due to respiratory or cardiac issues. Neurosurgical evaluation and management of such cases has only insufficiently been studied. We conducted a retrospective, cohort study of adult patients treated with ECMO between January 2007 and January 2017 in a tertiary healthcare center. Demographics, clinical data, coagulation status, ICH characteristics, and treatment modalities were analyzed. The primary outcome parameter was defined as mortality caused by ICH during ECMO. 525 patients with ECMO therapy were eligible for analysis. An overall incidence for any type of intracranial bleeding of 12.3% was found. Small hemorrhages accounted for 6.4% and acute subdural and epidural hematoma for 1.2%. Twenty-four (4.6%) patients developed ICH, and 11 patients (46%) died due to the ICH. Mortality was significantly higher in patients with larger ICH volumes (86.8 ± 34.8 ml vs 9.9 ± 20.3 ml, p < 0.001), intraventricular hemorrhage (83% vs 8%, p = 0.01), and a fluid level inside the ICH (75% vs 31%, p = 0.04). All patients were classified according to the bleeding pattern on the initial CT scan into 3 types. Patients with type 1 bleeding were statistically more likely to die (p < 0.001). In 15 out of 24 patients (63%), correction of the coagulation status was possible within 12 h after ICH onset. Seven out of 9 patients (78%) without early coagulation correction died compared to 2 out of 15 patients (13%), in whom early coagulation correction was successful (p = 0.01). This is the first study evaluating the course and management of patients experiencing an ICH under ECMO therapy and establishing an ICH classification based on the bleeding patterns. Early correction of the coagulation is of paramount importance in the treatment of these patients.

Clinical and economic impact of oxidized regenerated cellulose for surgeries in a Chinese tertiary care hospital

Aim: To assess the impact of oxidized regenerated cellulose (ORC) on blood transfusion and hospital costs associated with surgeries. Patients & methods: This retrospective cohort study selected ten surgeries to create propensity-score matching groups to compare ORC versus nonORC (conventional hemostatic techniques such as manual pressure, ligature and electrocautery). Results: NonORC was associated with both higher blood transfusion volume and higher hospital costs than ORC in endoscopic transnasal sphenoidal surgery, nonskull base craniotomy, hepatectomy, cholangiotomy, gastrectomy and lumbar surgery. However, nonORC was associated with better outcomes than ORC in open colorectal surgery, mammectomy and hip arthroplasty surgery. Conclusion: When compared with conventional hemostatic technique, using ORC could impact blood transfusion and hospital costs differently by surgical settings.

Perioperative dual antiplatelets management for ventriculoperitoneal shunt operation in patients with hydrocephalus after stent-assisted coil embolization of the ruptured intracranial aneurysm

OBJECTIVE

Ventriculoperitoneal shunt (VPS) surgery is sometimes necessary in patients who present with symptomatic hydrocephalus after undergoing stent-assisted coil embolization of ruptured intracranial aneurysms. However, there are no guidelines for the perioperative management of VPS using dual antiplatelet therapy (DAPT) and balancing between the thromboembolic and hemorrhagic complications. Studies regarding discontinuation of DAPT and its substitution with a less potent drug for reducing the risk of hemorrhage have been previously attempted; however, the sample size in these studies was small. This study investigates the safety and feasibility of ibuprofen bridging therapy with discontinuation of DAPT for five days in patients who have recently received a neurovascular stent and require VPS.

METHODS

Forty-one patients, who were administered DAPT after neurovascular stent placement and later underwent VPS, were retrospectively enrolled. Patients were divided into two groups based on the perioperative DAPT therapy: (1) Bridge: discontinuing DAPT and substituting it with ibuprofen 600 mg bid for five days, and (2) Continue: maintaining DAPT during surgery. The groups were compared and risk factors for hemorrhagic complication were investigated.

RESULTS

On comparison analysis, no ischemic complications were observed in both groups; however, hemorrhagic complications were significantly higher in the continue than in the bridge group (p = 0.004). On multivariate logistic regression analysis, "ibuprofen bridging" was identified as a significant factor negatively associated with hemorrhagic complications (p = 0.019).

CONCLUSION

"Ibuprofen bridging therapy with discontinuation of DAPT for 5 days" is a potential treatment strategy for patients having recently undergone neurovascular stent placement and are scheduled for VPS surgery.

Perioperative Coagulopathy in Patients with Normal Preoperative Coagulation Screen: A Couple of Coagulopathic Clinical Case Conundrums

Perioperative coagulopathy impacts patient outcome by influencing intraoperative hemodynamics and blood loss. We present two cases which despite having normal preoperative coagulation profiles and normotension during the surgery had intraoperative coagulopathy and unusual bleeding. These cases required a multidisciplinary approach to manage them successfully. A thorough knowledge of the coagulation cascade along with a high-degree of suspicion and early recognition of coagulation is required. Abnormalities are critical for a timely intervention. Point-of-care tests like thromboelastography (TEG) as well as platelet function studies helped us arrive at an early diagnosis and initiate prompt treatment.

Thromboelastometry as a Comprehensive Assessment of Hypercoagulation After Aneurysmal Subarachnoid Hemorrhage: A Case Report and Literature Review

Subarachnoid hemorrhage after cerebral aneurysm rupture (aSAH) leads to delayed cerebral ischemia (DCI) in 25-35% of surviving patients. It is believed that DCI has a multifactorial etiology, including vasospasm. Furthermore, aSAH is associated with the development of hypercoagulation and microthrombosis; thus, its pharmacological correction may help to prevent DCI. We encountered a case where hypercoagulation was detected using rotational thromboelastometry (ROTEM), although the standard coagulation test results were within the normal ranges. Based on reviews of viscoelastic tests in cases of aSAH, ROTEM could be more sensitive to hypercoagulation after aSAH, compared to standard coagulation testing.

[Current trends in the development of neuroanesthesiology]

The paper presents the author's analysis of the main trends in the development of modern neuroanesthesiology over the past five to ten years. These, in the author\s opinion, include the introduction and elaboration of blood-sparing techniques, monitoring the depth of anesthesia, fast track concept, applying regional (conduction) anesthesia techniques, xenon anesthesia, development of effective and safe protocols for DVT and PTE prophylaxis for neurosurgical patients, study of the hemostatic system using bedside methods for assessing hemostasis (thromboelastogram) and correcting hypocoagulation by activated recombinant VII factor.

Assessment of Haemostasis in patients undergoing emergent neurosurgery by rotational Elastometry and standard coagulation tests: a prospective observational study

BACKGROUND

Rotational elastometry (ROTEM) has been shown useful to monitor coagulation in trauma patients and in major elective surgery. In this study, we aimed to evaluate the utility of ROTEM to identify hemostatic disturbances and to predict the need for transfusion, compared with standard coagulation tests (SCTs) in patients undergoing emergent neurosurgery.

METHODS

Over a four-year period, adult patients who met criteria for emergent neurosurgery lasting more than 90 min were included in the study. Blood was collected preoperatively and analyzed with SCTs (international normalized ratio [INR], fibrinogen concentration, prothrombin time [PT or Quick], partial thromboplastine time [PTT], fibrinogen concentration and platelet count), and ROTEM assays. Correlations between SCTs and ROTEM parameters as well as receiver operating characteristic curves were performed to detect a coagulopathic pattern based on standard criteria and the need for transfusing at least 3 units of packed red blood cells (PRBCs).

RESULTS

In a cohort of 92 patients, 39 (42%) required ≥3 PRBCs and a coagulopathic pattern was identified in 32 patients based on SCTs and in 19 based on ROTEM. There was a strong correlation between PTT and INTEM coagulation time (R = 0.76) as well as between fibrinogen concentrations and FIBTEM maximal clot firmess (R = 0.70). The need for transfusion (≥ 3 PRBCs) was best predicted by the maximal clot firmess of EXTEM and FIBTEM (AUC of 0.72 and 0.71, respectively) and by fibrinogen concentration (AUC of 0.70).

CONCLUSIONS

In patients undergoing emergent neurosurgery, ROTEM analysis provides valid markers of early coagulopathy and predictors of blood transfusion requirements.

Systematic Review of Safety and Cost-Effectiveness of Venous Thromboembolism Prophylaxis Strategies in Patients Undergoing Craniotomy for Brain Tumor

BACKGROUND

Studies have evaluated various strategies to prevent venous thromboembolism (VTE) in neuro-oncology patients, without consensus.

OBJECTIVE

To perform a systematic review with cost-effectiveness analysis (CEA) of various prophylaxis strategies in tumor patients undergoing craniotomy to determine the safest and most cost-effective prophylaxis regimen.

METHODS

A literature search was conducted for VTE prophylaxis in brain tumor patients. Articles reporting the type of surgery, choice of VTE prophylaxis, and outcomes were included. Safety of prophylaxis strategies was determined by measuring rates of VTE and intracranial hemorrhage. Cost estimates were collected based on institutional data and existing literature. CEA was performed at 30 d after craniotomy, comparing the following strategies: mechanical prophylaxis (MP), low molecular weight heparin with MP (MP+LMWH), and unfractionated heparin with MP (MP+UFH) to prevent symptomatic VTE. All costs were reported in 2016 US dollars.

RESULTS

A total of 34 studies were reviewed (8 studies evaluated LMWH, 12 for MP, and 7 for UFH individually or in combination; 4 studies used LMWH and UFH preoperatively). Overall probability of VTE was 1.49% (95% confidence interval (CI) 0.42-3.72) for MP+UFH, 2.72% [95% CI 1.23-5.15] for MP+LMWH, and 2.59% (95% CI 1.31-4.58) for MP, which were not statistically significant. Compared to a control of MP alone, the number needed to treat for MP+UFH is 91 and 769 for MP+LMWH. The risk of intracranial hemorrhage was 0.26% (95% CI 0.01-1.34) for MP, 0.74% (95% CI 0.09-2.61) for MP+UFH, and 2.72% (95% CI 1.23-5.15) for MP+LMWH, which were also not statistically significant. Compared to MP, the number needed to harm for MP+UFH was 208 and for MP+LMWH was 41. Fifteen studies were included in the final CEA. The estimated cost of treatment was $127.47 for MP, $142.20 for MP+UFH, and $169.40 for MP+LMWH. The average cost per quality-adjusted life-year for different strategies was $284.14 for MP+UFH, $338.39 for MP, and $722.87 for MP+LMWH.

CONCLUSION

Although MP+LMWH is frequently considered the optimal prophylaxis for VTE risk reduction, our model suggests that MP+UFH is the safest and most cost-effective measure to balance VTE and hemorrhage risks in brain tumor patients at lower risk of hemorrhage. MP+LMWH may be more effective for patients at higher risk of VTE.

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

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

Magnetic Resonance Imaging Appearance and Mechanism of Action of Five Hemostatic Agents Used in Neurosurgery

OBJECTIVE

To describe the magnetic resonance (MR) image appearance of 5 hemostatic agents placed in the brain, and to review their clinical application.

STUDY DESIGN

Descriptive ex vivo and in vivo study.

ANIMALS

Canine cadavers (n=4), client-owned dogs (n=4).

METHODS

Heads from 4 canine cadavers were used, each with 5 hemostatic agents placed in specific locations in the brain. Hemostatic agents were used in their native form in 2 cadaveric brains, and in 2 others the materials were saturated with fresh whole blood prior to placement to mimic application in a field of active hemorrhage. The heads underwent MR imaging and the images were reviewed. Postoperative MRI images from 4 dogs undergoing brain tumor resection were retrospectively reviewed and compared to the images from the cadavers. All clinical cases and cadaveric specimens underwent surgical closure prior to MR imaging including placement of titanium mesh over the craniotomy defect with a dural graft of porcine small intestinal submucosa (SIS) sealed with Tisseel (fibrin sealant).

RESULTS

The SIS and Tisseel used in the dural graft were consistently indistinguishable from the surrounding tissues on MR images. The MR imaging appearance of the remaining 4 hemostatic agents (Gelfoam, Avitene, Surgicel, and Floseal) placed on the surface or in the parenchyma of canine brain, varied with MR sequence weighting and blood saturation.

CONCLUSION

Accurate evaluation of the degree of brain tumor resection on postoperative MR images requires careful differentiation between hemorrhage, residual tumor, and hemostatic agents implanted.

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.

Risk factors for intraoperative allogeneic blood transfusion during craniotomy for brain tumor removal in children

BACKGROUND

Several clinical and surgical factors can influence the occurrence of allogeneic blood transfusion (ABT) during oncologic neurosurgery.

OBJECTIVES

To identify the potential predictive factors of ABT during craniotomy for the removal of brain tumors in children and the potential impact of intraoperative ABT on early postoperative outcome.

METHODS

A retrospective study was performed in all pediatric patients younger than 18 years who underwent craniotomy for brain tumor removal from December 2009 to December 2012 in our institution. Pre-, intra-, and postoperative data were collected from medical and stored electronic anesthesia records. The predictors of intraoperative ABT were determined using multivariate logistic regression.

RESULTS

A total of 110 patients were included. Twenty-seven patients (25%) received intraoperative ABT with a volume of 16 ± 8 ml·kg(-1) . On multivariate analysis, an age <4 years, a duration of surgery >270 min, and a preoperative hemoglobin <12.2 g·dl(-1) were independently associated with the need for intraoperative ABT. We did not show any significant difference concerning postoperative early outcome and length of stay between the transfused and non-transfused patients except for the duration of postoperative mechanical ventilation that was significantly higher in the transfused group (P = 0.04).

CONCLUSION

In children, craniotomy for brain tumor removal is at risk of intraoperative ABT. An age <4 years, a duration of surgery >270 min, and a preoperative hemoglobin <12.2 g·dl(-1) are the main factors associated with intraoperative ABT during this surgery.

High prevalence of pharmacologically induced platelet dysfunction in the acute setting of brain injury

BACKGROUND

The management of patients with traumatic brain injury (TBI), primary intracerebral hemorrhage (pICH) and primary subarachnoid hemorrhage (pSAH) remains a highly demanding challenge in critical care medicine. Antithrombotic agents are one of the most relevant risk factors for poor outcome. However, in the acute setting of brain injury, information on preexisting medication might not be available. This group of patients is insufficiently characterized regarding pharmacologically induced platelet impairment.

METHODS

We retrospectively analyzed consecutive patients with TBI, pICH and pSAH admitted to our department with unknown preexisting medication. The impact of acetylsalicylic acid and ADP-receptor antagonists on platelet function was tested via the Multiplate analyzer. Patients' characteristics, management and the influence of platelet impairment on outcome were evaluated.

RESULTS

Within 25 months 103 patients with TBI (61), pICH (32) or pSAH (10) and unknown antithrombotic medication were admitted to our department. In 54 (52.4 %) of the patients reduced platelet function was detected, mainly caused by acetylsalicylic acid. In the TBI group, 30 patients (49.2 %) were identified, while Multiplate analysis detected platelet dysfunction in 19 (59.4 %) subjects in the pICH group and 5 in the pSAH group (50 %). In multivariable analysis the pathological Multiplate result was not associated with worse outcome; however, in our cohort 47 (87 %) patients received hemostatic therapy following detection of impaired platelet function.

CONCLUSION

Our results demonstrate the high frequency of pharmacologically impaired platelet function in patients with unknown preexisting medication. Early assessment of platelet function is an important tool to allow optimized treatment in these patients.

National survey on thromboprophylaxis and anticoagulant or antiplatelet management in neurosurgical and neurocritical patients

OBJECTIVES

To determine the protocols used by Spanish anaesthesiologists for thromboprophylaxis and anticoagulant or antiplatelet drugs management in neurosurgical or neurocritical care patients.

MATERIAL AND METHODS

An online survey with 22 questions, with one or multiple options, launched by the Neuroscience Subcommittee of the Spanish Anaesthesia Society and available between June and October 2012.

RESULTS

Of the 73 hospitals included in the National Hospitals Catalogue, a valid response to the online questionnaire was received by 41 anaesthesiologists from 37 sites (response rate 50.7%). Only one response per site was used. A specific protocol was available in 27% of these centres. Mechanical thromboprophylaxis is used, intraoperatively or postoperatively, in 80%, and pharmacological treatment is used by 75% of respondents. Enoxaparin was the most frequent heparin used in craniotomy patients (78%). Craniotomies were performed maintaining acetylsalicylic acid treatment in patients with coronary stents and double anti-platelet treatment in a half of the centres.

CONCLUSIONS

Mechanical thromboprophylaxis is used more frequently than the pharmacological approach in neurosurgical or neurocritical populations in Spanish hospitals. Management of patients under previous anticoagulant treatment was highly heterogeneous among hospitals included in this survey. Previous antiplatelet treatment is modified depending on primary or secondary prescription.

Point of care coagulation testing in neurosurgery

Impaired haemostasis represents a major risk factor for bleeding complications in neurosurgical patients. Coagulopathy commonly occurs after (brain) trauma and major haemorrhage or originates from antithrombotic medication. Point of care (POC) devices for bedside assessment of haemostatic parameters are increasingly used in various medical specialties. Results can be instantly implemented into treatment modalities as results are delivered within a very short period. POC coagulation testing has also shown beneficial effects in the treatment of neurosurgical patients. Identification of hyperfibrinolysis is achieved through viscoelastic testing of haemostasis and bedside coagulometry hastens the management of anticoagulated patients in need of urgent neurosurgical procedures. Results of POC testing of platelet function have been correlated with patient outcomes after traumatic brain injury and furthermore, quantification of antiplatelet medication effects on platelet activity is made possible through the use of these devices. Further studies are needed to characterise the potential of POC testing of platelet function. Antiplatelet medication plays an important role in regard to haemorrhagic and thromboembolic risks. Therefore, POC testing of platelet activity may improve treatment modalities in patients undergoing neurosurgical procedures as well as neurointerventional procedures (such as intracranial stent placement). In this article we summarise the available data of POC testing in neurosurgical patients and discuss the potential of these devices in this field. POC technologies have improved patient care in various medical fields and in our view it is likely that this will also apply to the field of neurosurgery.

Intraoperative blood loss during decompressive craniectomy for intractable intracranial hypertension after severe traumatic brain injury in children

PURPOSE

There are no data available on the risk of intraoperative bleeding during decompressive craniectomy (DC) after traumatic brain injury (TBI) in children. The objectives of this study were to assess the risk of intraoperative bleeding during DC for intractable intracranial hypertension after TBI, to identify potential factors associated with the risk of bleeding during DC, and to assess the impact of DC on systemic and cerebral hemodynamics and on coagulation.

METHODS

Twelve children were identified as having undergone DC after TBI from April 2009 to June 2013 in our center. Subjects were allocated into two groups according to the percentage of blood loss (IBL) during the intraoperative period (<or ≥50 % of the estimated blood volume (EBV)).

RESULTS

The median IBL during DC was 49 [17-349] % of the EBV. Children with an IBL ≥ 50 % of EBV had higher preoperative intracranial pressure (ICP) (p = 0.03) and international normalized ratio (INR) (p = 0.02) than those with an IBL < 50 % of EBV. DC induced significant decreases in ICP (p = 0.0005), mean arterial pressure (p = 0.01), and a significant increase in norepinephrine flow rate (p = 0.04) between the immediate pre- and postoperative periods.

CONCLUSIONS

DC allows a significant decrease in ICP after severe pediatric TBI but is a surgical procedure at a high risk of bleeding. High ICP and INR during the immediate preoperative period are the main factors associated with increased IBL during DC. Further studies are needed to confirm our results and to assess the impact of the amount of IBL on the postoperative survival and functional outcome.

Bleeding management for pediatric craniotomies and craniofacial surgery

Pediatric patients when undergoing craniotomies and craniofacial surgery may potentially have significant blood loss. The amount and extent will be dictated by the nature of the surgical procedure, the proximity to major blood vessels, and the age, and weight of the patient. The goals should be to maintain hemodynamic stability and oxygen carrying capacity and to prevent and treat hyperfibrinolysis and dilutional coagulopathy. Over transfusion and transfusion-related side effects should be minimized. This article will highlight the pertinent considerations for managing massive blood loss in pediatric patients undergoing craniotomies and craniofacial surgery. North American and European guidelines for intraoperative administration of fluid and blood products will be discussed.

Effects of remote ischemic preconditioning on the coagulation profile of patients with aneurysmal subarachnoid hemorrhage: a case-control study

BACKGROUND

Animal studies suggest that ischemic preconditioning prolongs coagulation times.

OBJECTIVE

Because coagulation changes could hinder the translation of preconditioning into clinical settings where hemorrhage may be an issue, such as ischemic or hemorrhagic stroke, we evaluated the effects of remote ischemic preconditioning (RIPC) on coagulation in patients undergoing RIPC after aneurysmal subarachnoid hemorrhage (SAH).

METHODS

Twenty-one patients with SAH (mean age, 56.3 years) underwent 137 RIPC sessions 2 to 12 days after SAH, each consisting of 3 to 4 cycles of 5 to 10 minutes of lower limb ischemia followed by reperfusion. Partial thromboplastin time (PTT), prothrombin time (PT), and international normalized ratio (INR) were analyzed before and after sessions. Patients were followed for hemorrhagic complications.

RESULTS

No immediate effect was identified on PTT (mean pre-RIPC, 27.62 s; post-RIPC, 27.54 s; P = .82), PT (pre-RIPC, 10.77 s; post-RIPC, 10.81 s; P = .59), or INR (pre-RIPC, 1.030; post-RIPC, 1.034; P = .57) after each session. However, statistically significant increases in PT and INR were identified after exposure to at least 4 sessions (mean PT pre-RIPC, 11.33 s; post-RIPC, 12.1 s; P = .01; INR pre-RIPC, 1.02; post-RIPC, 1.09; P = .014, PTT pre-RIPC, 27.4 s; post-RIPC, 27.85 s; P = .092) with a direct correlation between the number of sessions and the degree of increase in PT (Pearson correlation coefficient = 0.59, P = .007) and INR (Pearson correlation coefficient = 0.57, P = .010). Prolonged coagulation times were not observed in controls. No hemorrhagic complications were associated with the procedure.

CONCLUSION

RIPC by limb ischemia appears to prolong the PT and INR in human subjects with SAH after at least 4 sessions, correlating with the number of sessions. However, values remained within normal range and there were no hemorrhagic complications.

Reduction of thromboembolic events in meningioma surgery: a cohort study of 724 consecutive patients

Background

Meningiomas are associated with the highest postoperative rate of venous thromboembolic events (VTE) among all intracranial tumors. The aim of this study is to compare two entirely different VTE prophylaxis regimens in 724 consecutive patients undergoing meningioma surgery.

Methods

Two cohorts at a single institution treated with different regimens to prevent VTE were reviewed retrospectively. Cohort A (n = 482; 314 females, mean age 57 years, range: 11–87 years) received our institutional regimen during the years 1999–2006, consisting of low-molecular-weight heparin (LMWH) and compression stockings. For cohort B (n = 242; 163 females, mean age 56.8 years, range: 16–90 years), during the years 2008–2010, the management included intraoperative 10°–20° leg elevation with intermittent pneumatic compression (IPC), heparin and LMWH administration. We compared the incidence of the endpoints pulmonary embolism (PE), deep venous thrombosis (DVT), hemorrhage and death, taking into account several known associated risk factors.

Results

For all endpoints, we observed a more favorable outcome with the new regimen. The difference in incidence of PEs (cohort A: 38/482, 8%; cohort B: 6/242, 2.5%) reached statistical significance (p = 0.002). In general, patients with skull base meningiomas had a higher risk for PE (OR 2.77). Regarding VTE prophylaxis, an adjusted subgroup analysis suggests that the new regimen is particularly beneficial for patients with skull base meningiomas.

Conclusions

We recommend perioperative prophylaxis using a management composed of intraoperative leg-elevation, IPC, early heparin administration and LMWH to reduce the risk for PE.

Multiple electrode aggregometry in antiplatelet-related intracerebral haemorrhage

As the population ages, antiplatelet agents are increasingly used in patients with cardiovascular diseases. Due to impaired platelet activity, these patients are at increased risk for bleeding complications and this is of particular importance in patients with intracerebral haemorrhage. The multiple electrode aggregometry analyser Multiplate (Roche Diagnostics, Mannheim, Germany) was introduced in 2006 to monitor the effectiveness of antiplatelet drugs in interventional cardiology. As a point-of-care device, it allows bedside assessment of platelet activity within minutes through analysis of a sample of whole blood. In patients treated with antiplatelet medication and in need of urgent cardiac surgery, these devices allow prediction of intraoperative blood loss and their use was implemented within respective guidelines to direct transfusion strategies. We used the Multiplate analyser for rapid assessment of antiplatelet activity in a patient who developed an intracerebral haemorrhage after administration of aspirin and clopidogrel. Antiplatelet activity was assessed within 10 minutes while the patient was transferred to the operating room and after transfusion of platelet concentrates and administration of desmopressin and tranexamic acid, repeated Multiplate analysis demonstrated nearly normalized platelet activity. In our view, there is great potential for this device to improve treatment in neurosurgery and especially the treatment of antiplatelet-related intracerebral haemorrhage. Instant assessment of antiplatelet activity or effectiveness of haemostatic measures is facilitated and furthermore, patients with normal platelet activity despite a positive history of antiplatelet medication intake can be identified. In these patients, empiric administration of haemostatic substances would unnecessarily increase the risk of thromboembolic events.

Initial experiences with Multiplate® for rapid assessment of antiplatelet agent activity in neurosurgical emergencies

OBJECTIVE

As the population ages, physicians encounter a growing number of patients who are treated with antiplatelet agents and present with severe conditions requiring urgent neurosurgical therapy. Standard laboratory investigations are insufficient to evaluate platelet activity and furthermore, it is difficult to evaluate effects of haemostatic measures on platelet function. In this article we report our initial experiences with the point-of-care device Multiplate® for assessment of platelet activity in neurosurgical emergencies on patients with a reported intake of antiplatelet medication.

METHODS

Multiplate® assessment of antiplatelet activity was carried out in 21 non-consecutive patients with a reported intake of antiplatelet medication (aspirin: n=21, clopidogrel: n=3, ticragrelor: n=1) and urgent admission to our hospital because of conditions such as intracranial haemorrhage requiring urgent neurosurgical therapy. Analysis was repeated in order to evaluate the effectiveness of haemostatic drugs and platelet concentrate transfusion on platelet activity in six patients.

RESULTS

No technical difficulties occurred and in all cases, results were obtained within 15 min. On admission, patients' arachidonic acid induced platelet activity was reduced by 44.4±33.5% (range: -79.7% to +44.3%) compared to the lower reference limit. Two patients had a normal platelet activity despite a reported intake of aspirin. Haemostatic measures significantly increased arachidonic acid induced platelet activity by 100±66% (p<0.005).

CONCLUSION

The Multiplate® device allowed rapid assessment of antiplatelet agent activity and evaluation of haemostatic measures on platelet activity. Further studies with larger patient numbers are needed, but this device may represent a valuable tool to improve treatment modalities in patients treated with antiplatelet medication and conditions requiring urgent neurosurgical therapy.

On the value of routine prothrombin time screening in elective neurosurgical procedures

Object

The authors performed a study to evaluate whether preoperative assessment of prothrombin time (PT) is mandatory in patients undergoing routinely planned neurosurgical procedures.

Methods

The charts of all patients admitted to general wards of the authors' department for routinely planned surgery (excluding trauma and ICU patients) between 2006 and 2010 were retrospectively reviewed. The authors assessed preoperative PT and the clinical courses of all patients, with special consideration for patients receiving coagulation factor substitution. All cases involving hemorrhagic complications were analyzed in detail with regard to pre- and postoperative PT abnormalities. Prothrombin time was expressed as the international normalized ratio, and values greater than 1.28 were regarded as elevated.

Results

Clinical courses and PT values of 4310 patients were reviewed. Of these, 33 patients (0.7%) suffered hemorrhagic complications requiring repeat surgery. Thirty-one patients (94%) had a normal PT before the initial operation, while 2 patients had slightly elevated PT values of 1.33 and 1.65, which were anticipated based on the patient's history. In the latter 2 cases, surgery was performed without prior correction of PT. Preoperatively, PT was elevated in 78 patients (1.8%). In 73 (93.6%) of the 78 patients, the PT elevation was expected and explained by each patient's medical history. In only 5 (0.1%) of 4310 patients did we find an unexpected PT elevation (mean 1.53, range 1.37–1.74). All 5 patients underwent surgery without complications, while 2 had received coagulation factor substitution preoperatively, as requested by the surgeon, because of an estimated risk of bleeding complications. None of the 5 patients received coagulation factor substitution postoperatively, and later detailed laboratory studies ruled out single coagulation factor deficiencies. There was no statistically significant association between preoperatively elevated PT levels and the occurrence of hemorrhagic complications (p = 0.12). Before the second procedure but not before the initial operation, 4 (12%) of the 33 patients had elevated PT.

Conclusions

The findings suggest that the value of preoperative PT testing is limited in patients in whom a normal history can be ascertained. Close postoperative PT control is necessary in every neurosurgical patient, and better tests need to be developed to identify patients who are prone to hemorrhagic complications.

Perioperative management of a neurosurgical patient requiring antiplatelet therapy

In patients who undergo neurovascular stent placement with postoperative dual antiplatelet therapy to prevent in-stent thrombosis, there is no protocol for balancing the risk of acute stent thrombosis and bleeding if urgent neurosurgical procedures are required. We detail perioperative management of dual antiplatelet therapy in a 66-year-old man with a dolichoectatic aneurysm of the basilar artery treated with a Pipeline stent. Postoperatively, the patient was placed on aspirin and clopidogrel to prevent in-stent thrombosis. One month after the procedure, his neurological status declined secondary to obstructive hydrocephalus. His condition necessitated urgent placement of a ventriculoperitoneal shunt, despite the dual antiplatelet therapy for the flow-diverting Pipeline stent. Aspirin and clopidogrel were discontinued seven days prior to the planned shunt placement. To minimize time off antiplatelet therapy, aspirin was immediately replaced with ibuprofen. Eptifibatide was then started three days prior to surgery. The ibuprofen/eptifibatide bridge was discontinued at midnight prior to surgery. Aspirin was restarted on the first postoperative day and clopidogrel was restarted on the second postoperative day. The patient tolerated shunt placement without excessive bleeding or hemorrhagic complications. During the remainder of his hospital course, no evidence of stent thrombosis or intracranial hemorrhage was noted. We conclude that management of antiplatelet prophylaxis for neurovascular stent thrombosis in patients requiring urgent neurosurgical procedures may be successfully achieved by bridging aspirin and clopidogrel with ibuprofen and eptifibatide in the preoperative period.

Reduction of Fresh Frozen Plasma Requirements by Perioperative Point-of-Care Coagulation Management with Early Calculated Goal-Directed Therapy

BACKGROUND: Massive bleeding and transfusion of packed red blood cells (PRBC), fresh frozen plasma (FFP) and platelets are associated with increased morbidity, mortality and costs. PATIENTS AND METHODS: We analysed the transfusion requirements after implementation of point-of-care (POC) coagulation management algorithms based on early, calculated, goal-directed therapy with fibrinogen concentrate and prothrombin complex concentrate (PCC) in different perioperative settings (trauma surgery, visceral and transplant surgery (VTS), cardiovascular surgery (CVS) and general and surgical intensive care medicine) at 3 different hospitals (AUVA Trauma Centre Salzburg, University Hospital Innsbruck and University Hospital Essen) in 2 different countries (Austria and Germany). RESULTS: In all institutions, the implementation of POC coagulation management algorithms was associated with a reduction in the transfusion requirements for FFP by about 90% (Salzburg 94%, Innsbruck 88% and Essen 93%). Furthermore, PRBC transfusion was reduced by 8.4-62%. The incidence of intraoperative massive transfusion (≥10 U PRBC) could be more than halved in VTS and CVS (2.56 vs. 0.88%; p < 0.0001 and 2.50 vs. 1.06%; p = 0.0007, respectively). Platelet transfusion could be reduced by 21-72%, except in CVS where it increased by 115% due to a 5-fold increase in patients with dual antiplatelet therapy (2.7 vs. 13.7%; p < 0.0001). CONCLUSIONS: The implementation of perioperative POC coagulation management algorithms based on early, calculated, goal-directed therapy with fibrinogen concentrate and PCC is associated with a reduction in the transfusion requirements for FFP, PRBC and platelets as well as with a reduced incidence of massive transfusion. Thus, the limited blood resources can be used more efficiently.

The prognostic value of thrombelastography in identifying neurosurgical patients with worse prognosis

Coagulopathy in patients with intracranial haemorrhage or traumatic brain injury (TBI) is associated with clinical deterioration and worse outcome. Whole blood viscoelastic haemostatic assays, like thrombelastography (TEG), might aid conventional coagulation assays in identification of patients with worse prognosis. We performed a review of patients (totalling 78 patients) with primary acute intracranial haemorrhage or isolated TBI admitted to a neurointensive care unit (NICU) for more than 24 h during a period of 9 months, who had TEG analysis performed at admission. Primary outcome was all-cause 30-day mortality, whereas decline in Glasgow Coma Scale (GCS) score at 24 h after admission or death due to cerebral incarceration were secondary outcomes. Patients were defined as hypocoaguable if TEG reaction time was more than 8 min, angle less than 55° and/or maximal amplitude less than 51 mm. Patients were defined hypocoaguable according to conventional coagulation assays if international normalized ratio was more than 1.3, platelet counts less than 100×10/l and/or activated partial thromboplastine time more than 35 s. Eight patients were hypocoaguable by TEG on admission to NICU and had higher 30-day mortality (63% vs. 16%, P=0.008), more often declined in GCS (57% vs. 16%, P=0.02) and expired due to cerebral incarceration (50% vs. 6%, P=0.02). Hypocoagulability by TEG, lower admission GCS and subarachnoid haemorrhage were independently associated with higher 30-day mortality [TEG: odds ratio (OR) 14.8 (2.2-100.1), P=0.006; GCS: OR 1.3 (1.1-1.5), P=0.006; subarachnoid haemorrhage: OR: 5.3 (1.3-22.3), P=0.02]. Only two patients were hypocoaguable by both conventional coagulation assays and TEG. The current data indicate that hypocoagulability by TEG at admission to NICU predicts worse prognosis. Low concordance with conventional coagulation assays indicates that TEG might be valuable in identifying patients with clinically relevant coagulopathy.

Illustration of the impact of antiplatelet drugs on the genesis and management of chronic subdural hematoma

The case of a 76-year-old male with a large chronic subdural hematoma that showed total regression with the mere suspension of aspirin, its only apparent causal factor, and that of an 81 year-old male on aspirin and clopidogrel with a chronic subdural hematoma who succumbed after burr holes due to two simultaneous severe hemorrhagic complications (cerebellar hemorrhage and ipsilateral acute subdural hematoma) are presented. The cases may provide support for the following management strategies: (i) if conservative management and drug suspension are feasible, they may well be worth trying and lead to a favorable outcome; (ii) if a patient is at risk of developing a chronic subdural hematoma, namely because of a minor acute subdural hematoma, withdrawal of antiplatelet agents should be considered; (iii) if surgery is necessary, its delay allows for the metabolization of the drug and platelet renewal, thereby minimizing the risk of hemorrhage; (iv) if urgent burr holes are indicated, measures to improve platelet function should be undertaken.

Goal-directed coagulation management of major trauma patients using thromboelastometry (ROTEM)-guided administration of fibrinogen concentrate and prothrombin complex concentrate

Introduction

The appropriate strategy for trauma-induced coagulopathy management is under debate. We report the treatment of major trauma using mainly coagulation factor concentrates.

Methods

This retrospective analysis included trauma patients who received ≥ 5 units of red blood cell concentrate within 24 hours. Coagulation management was guided by thromboelastometry (ROTEM^®). Fibrinogen concentrate was given as first-line haemostatic therapy when maximum clot firmness (MCF) measured by FibTEM (fibrin-based test) was <10 mm. Prothrombin complex concentrate (PCC) was given in case of recent coumarin intake or clotting time measured by extrinsic activation test (EXTEM) >1.5 times normal. Lack of improvement in EXTEM MCF after fibrinogen concentrate administration was an indication for platelet concentrate. The observed mortality was compared with the mortality predicted by the trauma injury severity score (TRISS) and by the revised injury severity classification (RISC) score.

Results

Of 131 patients included, 128 received fibrinogen concentrate as first-line therapy, 98 additionally received PCC, while 3 patients with recent coumarin intake received only PCC. Twelve patients received FFP and 29 received platelet concentrate. The observed mortality was 24.4%, lower than the TRISS mortality of 33.7% (P = 0.032) and the RISC mortality of 28.7% (P > 0.05). After excluding 17 patients with traumatic brain injury, the difference in mortality was 14% observed versus 27.8% predicted by TRISS (P = 0.0018) and 24.3% predicted by RISC (P = 0.014).

Conclusions

ROTEM^®-guided haemostatic therapy, with fibrinogen concentrate as first-line haemostatic therapy and additional PCC, was goal-directed and fast. A favourable survival rate was observed. Prospective, randomized trials to investigate this therapeutic alternative further appear warranted.