The Role of Desmopressin on Hematoma Expansion in Patients with Mild Traumatic Brain Injury Prescribed Pre-injury Antiplatelet Medications

Antiplatelet Reversal Is Not Associated With Decreased Progression of Intracranial Hemorrhage in Near-Isolated Traumatic Brain Injury: A Retrospective Clustered Analysis From Two Trauma Centers

INTRODUCTION

Antiplatelet agents (AAs) may increase the risk of intracranial hemorrhage (ICH). It is unclear whether reversal of antiplatelet effects (REV = desmopressin acetate [DDAVP] + Platelets) decreases ICH progression. The goal of the study was to determine whether REV was associated with decreased progression of ICH on repeat brain computed tomography (CT) scan.

METHODS

This is a clustered study (November 2019 to March 2022) at two regionally distinct trauma centers (TCs) with differing standards of practice in patients with ICH, one reversal with DDAVP + Platelets (REV+) and the other no reversal with DDAVP + Platelets (REV-). Using electronic and manual chart review, data were collected on inpatients aged ≥ 18 y on preinjury AAs with CT proven ICH (abbreviated injury scale head ≥ 2) and no other abbreviated injury scale > 2 injuries, who had at least one repeat CT scan within 120 h of admission. ICH progression on repeat brain CT scan, mortality, and resource utilization were compared via univariate analysis (α = 0.05).

RESULTS

One hundred fourteen patients were enrolled: 72 REV+ at the first TC and 42 REV- at the second TC. REV+ group had fewer White patients and a lower proportion on preinjury aspirin but were otherwise similar. ICH progression rate was 24/72 (33.3%) for REV+ and 11/42 (26.2%) for REV- (P = 0.43). Isolated subarachnoid hemorrhage was the most common lesion, followed by isolated subdural hemorrhage. No patients required cranial surgery. All-cause mortality (expired + hospice) was 5/72 (6.9%) and 1/42 (2.4%), respectively (P = 0.29).

CONCLUSIONS

In this study of patients on preinjury AAs, REV was not associated with decreased ICH progression, lower mortality, or less resource utilization. These findings should be confirmed in a larger, prospective study.

Are geriatric transfer patients with traumatic brain injury at risk for worse outcomes compared to non-geriatric? Propensity-matched study

OBJECTIVE

To compare outcomes between geriatric and non-geriatric patients with traumatic brain injury (TBI) transferred to trauma center and effects of anticoagulants/antiplatelets (AC/AP) and reversal therapy.

METHODS

A retrospective review of 1,118 patients with TBI transferred from acute care facilities to level 1 trauma center compared in groups: geriatric versus non-geriatric, geriatric with AC/AP therapy versus without, and geriatric AC/AP with AC/AP reversal therapy versus without.

RESULTS

Patients with TBI constituted 54.4% of trauma transfers. Mean transfer time was 3.9 h. Propensity matched by Injury Severity Score and Abbreviated Injury Score (AIS) head geriatric compared to non-geriatric patients had more AC/AP use (53.9% vs 8.8%), repeat head computed tomography (93.7% vs 86.1%), intensive care unit (ICU) admissions (57.4% vs 45.7%) and mortality (9.8% vs 3.2%), all p < 0.004. Patients on AC/AP versus without had more ICU admissions (69.1% vs 51.8%, p < 0.001). Patients with AC/AP reversals compared to without reversals had more AIS head 5 (32.0% vs 13.1%), brain surgeries (17.8% vs 3.5%) and ICU admissions (84.8% vs 57.1%), all p < 0.001.

CONCLUSION

TBI constituted half of trauma transfers and 10% required surgery. Based on higher ICU admissions, mortality, and prevalence of AC/AP therapy requiring reversal, geriatric patients with TBI on anticoagulants/antiplatelets should be considered for direct trauma center admission.

A multicenter study of DDAVP versus platelet transfusions for antiplatelet agent reversal in patients with traumatic brain injury

BACKGROUND

Antiplatelet agents have been shown to worsen outcomes following traumatic injury. Research on desmopressin (DDAVP) and platelet transfusion for antiplatelet reversal is limited. We aimed to evaluate the effect of these agents on patients taking pre-injury antiplatelet medications who experienced traumatic brain injury (TBI) after blunt trauma.

METHODS

This is a retrospective cohort study of adult trauma patients from 2014 to 2021 on aspirin and/or a P2Y12 inhibitor. Patients were stratified into groups based on if they received DDAVP, platelets, both agents, or neither.

RESULTS

Of 5525 included patients, 4696 (85.4%) were not reversed, 461 (8.4%) received platelets, 173 (3.1%) received DDAVP, and 172 (3.1%) received both reversals. There was no statistically significant difference in length of stay between, but patients who received platelets or both reversals were more likely to have hospital complications (p < 0.05), longer hospital length of stay (p < 0.001), and longer ICU length of stay (p < 0.001) compared to those who did not receive reversal. A subgroup analysis of patients with a head AIS of 4 or 5 confirmed these findings.

CONCLUSIONS

Patients who received platelets or both reversals had a longer length of hospital stay and length of ICU stay. It is difficult to recommend one treatment over another based on our results alone. Further studies are needed to help clarify the risks and benefits of reversal agents in this patient population.

Desmopressin, Misoprostol, nor Carboprost Affect Platelet Aggregability Following Traumatic Brain Injury and Aspirin

INTRODUCTION

Desmopressin (DDAVP) has been utilized clinically in patients taking aspirin (ASA) to improve drug-induced platelet dysfunction. Misoprostol and carboprost, prostaglandin analogs commonly used for postpartum hemorrhage, may also induce platelet aggregation. The aim of this study was to determine the effects of DDAVP, misoprostol, and carboprost administration on platelet aggregability following traumatic brain injury (TBI) in mice treated with ASA.

METHODS

Male C57BL/6 mice were randomized into seven groups (n = 5 each): untouched, ASA only, Saline/TBI, ASA/TBI, ASA/TBI/DDAVP 0.4 μg/kg, ASA/TBI/misoprostol 1 mg/kg, and ASA/TBI/carboprost 100 μg/kg. TBI was induced via a weight drop model 4-h after ASA (50 mg/kg) gavage. Mice were given an intraperitoneal injection of DDAVP, misoprostol, or carboprost 10 minutes after TBI. In vivo testing was completed utilizing tail vein bleed. Mice were sacrificed 30-min posttreatment and blood was collected via cardiac puncture. Whole blood was analyzed via Multiplate impedance aggregometry, rotational thromboelastometry, and TEG6s.

RESULTS

Mice receiving misoprostol after ASA/TBI demonstrated decreased tail vein bleeding times compared to ASA only treated mice. However, mice treated with misoprostol following ASA and TBI demonstrated decreased platelet aggregability compared to untouched mice and TBI only mice within the arachidonic acid agonist pathway. By contrast, DDAVP and carboprost did not significantly change platelet aggregability via adenosine diphosphate or arachidonic acid following ASA and TBI. However, DDAVP did decrease the platelet contribution to clot via rotational thromboelastometry.

CONCLUSIONS

Reversal of medication-induced platelet inhibition has become increasingly controversial after TBI. Based on these results, DDAVP, misoprostol, nor carboprost consistently improve platelet aggregability following TBI in those also treated with ASA.

[Update on point-of-care-based coagulation treatment : Systems, reagents, device-specific treatment algorithms]

Viscoelastic test (VET) procedures suitable for point-of-care (POC) testing are in widespread clinical use. Due to the expanded range of available devices and in particular due to the development of new test approaches and methods, the authors believe that an update of the current treatment algorithms is necessary. The aim of this article is to provide an overview of the currently available VET devices and the associated reagents. In addition, two treatment algorithms for the VET devices most commonly used in German-speaking countries are presented.

[Correction of the effect of vitamin K antagonists and antiplatelet agents in hemorrhagic stroke]

BACKGROUND

Hemorrhagic stroke (HS) is associated with high risk of mortality or disability. To date, up to 25% of HSs are associated with anticoagulants and antiplatelet agents. Early hemostatic therapy and correction of effect of antithrombotic drugs in patients with HS significantly reduce the risk of adverse outcomes. The latest international guidelines on this issue were presented almost 10 years ago.

MATERIAL AND METHODS

In accordance with the PRISMA recommendations, we reviewed the PubMed, eLibrary and UpToDate databases and identified 137 articles. Of these, 52 were enrolled as the most relevant.

RESULTS AND DISCUSSION

Regarding correction of the effect of indirect anticoagulants, various researchers discuss the possibility of either individual dosing or injection of a fixed dose of 4- or 3-factor prothrombin complex (1000-2000 IU regardless of body weight and international normalized ratio). To correct the effect of antiplatelet agents, platelet transfusion and desmopressin are proposed. There is currently no evidence of safety and effectiveness of both methods in patients with HS.

CONCLUSION

The optimal drug for correction of the effect of indirect anticoagulants is 4- or 3-factor prothrombin complex. In the last case, it is necessary to administer factor VIIa or fresh frozen plasma, as well as parenteral form of phytomenadione (vitamin K1) in all cases. The issue of correction of the effects of antiplatelet agents remains open. Regular analysis of available data with updating the guidelines for correction of the effect of anticoagulants and antiplatelet agents in HS is necessary.

Factor VIII: A Dynamic Modulator of Hemostasis and Thrombosis in Trauma

A trace amount of thrombin cleaves factor VIII (FVIII) into an active form (FVIIIa), which catalyzes FIXa-mediated activation of FX on the activated platelet surface. FVIII rapidly binds to von Willebrand factor (VWF) after secretion and becomes highly concentrated via VWF-platelet interaction at a site of endothelial inflammation or injury. Circulating levels of FVIII and VWF are influenced by age, blood type (nontype O > type O), and metabolic syndromes. In the latter, hypercoagulability is associated with chronic inflammation (known as thrombo-inflammation). In acute stress including trauma, releasable pools of FVIII/VWF are secreted from the Weibel-Palade bodies in the endothelium and then augment local platelet accumulation, thrombin generation, and leukocyte recruitment. Early systemic increases of FVIII/VWF (>200% of normal) levels in trauma result in a lower sensitivity of contact-activated clotting time (activated partial thromboplastin time [aPTT] or viscoelastic coagulation test [VCT]). However, in severely injured patients, multiple serine proteases (FXa plasmin and activated protein C [APC]) are locally activated and may be systemically released. Severity of traumatic injury correlates with prolonged aPTT and elevated activation markers of FXa, plasmin, and APC, culminating in a poor prognosis. In a subset of acute trauma patients, cryoprecipitate that contains fibrinogen, FVIII/VWF, and FXIII is theoretically advantageous over purified fibrinogen concentrate to promote stable clot formation, but comparative efficacy data are lacking. In chronic inflammation or subacute phase of trauma, elevated FVIII/VWF contributes to the pathogenesis of venous thrombosis by enhancing not only thrombin generation but also augmenting inflammatory functions. Future developments in coagulation monitoring specific to trauma patients, and targeted to enhancement or inhibition of FVIII/VWF, are likely to help clinicians gain better control of hemostasis and thromboprophylaxis. The main goal of this narrative is to review the physiological functions and regulations of FVIII and implications of FVIII in coagulation monitoring and thromboembolic complications in major trauma patients.

Practical Guide for Anticoagulant and Antiplatelet Reversal in Clinical Practice

In recent years, anticoagulant and antiplatelet use have increased over the past years for the prevention and treatment of several cardiovascular conditions. Due to the rising use of antithrombotic medications and the complexity of specific clinical cases requiring such therapies, bleeding remains the primary concern among patients using antithrombotics. Direct oral anticoagulants (DOACs) include rivaroxaban, apixaban, edoxaban, and betrixaban. Direct thrombin inhibitors (DTIs) include argatroban, bivalirudin, and dabigatran. DOACs are associated with lower rates of fatal, life-threatening, and significant bleeding risks compared to those of warfarin. The immediate reversal of these agents can be indicated in an emergency setting. Antithrombotic reversal recommendations are still in development. Vitamin K and prothrombin complex concentrate (PCCs) can be used for warfarin reversal. Andexanet alfa and idarucizumab are specific reversal agents for DOACs and DTIs, respectively. Protamine sulfate is the solely approved reversal agent for unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH). However, there are no specific reversal agents for antiplatelets. This article aims to provide a practical guide for clinicians regarding the reversal of anticoagulants and antiplatelets in clinical practice based on the most recent studies.

A multicenter retrospective study evaluating the impact of desmopressin on hematoma expansion in patients with antiplatelet-associated intracranial hemorrhage

INTRODUCTION

Antiplatelet medications interfere with hemostasis which can contribute to increased risk of hematoma expansion and potentially worse outcomes in patients presenting with intracranial hemorrhages (ICH). Current Neurocritical Care Society guidelines recommend desmopressin (DDAVP) in patients with antiplatelet-associated ICH with evidence limited by small cohorts.

MATERIALS AND METHODS

Patients were included in our multi-center, retrospective study if they had computed tomographic (CT) scan confirmed ICH and were taking antiplatelet medications. Patients were excluded if hospital length of stay was <24 h, administered DDAVP dose was <0.3 μg/kg, no follow-up head CT scan was performed within the first 24 h after baseline, major neurosurgical intervention was performed in between CT scans, or the injury was an acute on chronic ICH. The primary outcome was incidence of hematoma expansion (defined as >20 % increase from baseline). Secondary outcomes were incidence of thrombotic complications within 7 days, largest absolute decrease in serum sodium within the first 24 h, and patient disposition.

RESULTS

Among the 209 patients included in the study, 118 patients received DDAVP while 91 did not. The frequency of hematoma expansion was similar between patients who received DDAVP and those who did not (16.1 % vs 17.6 %; P = 0.78). No difference in secondary outcomes was observed between the two groups.

CONCLUSIONS

These findings in conjunction with recently published literature may suggest minimal benefit or harm with DDAVP treatment. However, further study could elucidate any potential impact on long-term function outcomes.

Dosing Medications for Coagulopathy Reversal in Patients with Extreme Obesity

BACKGROUND

The reversal of anticoagulant or antiplatelet medications is a priority in the management of patients with severe injury with the goal of minimizing further bleeding without thrombotic complications. There are few studies, however, evaluating the dosing of reversal agents in the setting of trauma specific to patients with extreme obesity. Nevertheless, clinicians must still make decisions, balancing concerns of ongoing bleeding with excessive thrombosis.

OBJECTIVES

We describe the literature pertaining to dosing of medications used for the reversal of both drug-induced and trauma-related coagulopathy with the intent of providing a framework for clinicians to make dosing decisions in this challenging population.

DISCUSSION

Obesity is known to impact both the volume of distribution and the clearance of medications, but these changes are not usually linear with size nor are they uniform across drugs. Current strategies for dosing reversal agents in obesity include a capped dose (e.g., prothrombin complex concentrates), fixed dosages (e.g., andexanet alfa, idarucizumab, and tranexamic acid), and weight-based dosing (e.g., desmopressin). Extreme obesity, however, was not highly prevalent in the studies that have validated these dosing strategies. In fact, many of the clinical studies fail to report the average weight of the patients included.

CONCLUSION

Future studies should make efforts to increase reporting of patients with obesity included in clinical trials along with results stratified by weight class. In the meantime, doses listed in product labels should be used. Desmopressin should be dosed using either ideal body weight or a dose-capping strategy.

Application of a TEG-Platelet Mapping Algorithm to Guide Reversal of Antiplatelet Agents in Adults with Mild-to-Moderate Traumatic Brain Injury: An Observational Pilot Study

BACKGROUND

Traumatic intracranial hemorrhages expand in one third of cases, and antiplatelet medications may exacerbate hematoma expansion. However, the reversal of an antiplatelet effect with platelet transfusion has been associated with harm. We sought to determine whether a thromboelastography platelet mapping (TEG-PM)-guided algorithm could limit platelet transfusion in patients with hemorrhagic traumatic brain injury (TBI) prescribed antiplatelet medications without a resultant clinically significant increase in hemorrhage volume, late hemostatic treatments, or delayed operative intervention.

METHODS

A total of 175 consecutive patients with TBI were admitted to our university-affiliated, level I trauma center between March 2016 and December 2019: 54 preintervention patients (control) and 121 patients with TEG-PM (study). After exclusion for anticoagulant administration, availability of neuroimaging and emergent neurosurgery, 62 study patients and 37 control patients remained. Intervention consisted of administration of desmopressin (DDAVP) for nonsurgical patients with significant inhibition at the arachidonic acid or adenosine diphosphate receptor sites. For surgical patients with significant inhibition, dual therapy with DDAVP and platelet transfusion was employed. Study patients were compared with a group of historical controls, which were identified from a prospectively maintained registry and typically treated with empiric platelet transfusion.

RESULTS

Median age was 75 years (interquartile range 85-67) and 77 years (interquartile range 81-65) in the TEG-PM and control patient groups, respectively. Admission hemorrhage volumes were similar (10.7 cm³ [20.1] in patients with TEG-PM vs. 14.1 cm³ [19.7] in controls; p = 0.41). There were no significant differences in admission Glasgow Coma Scale, mechanism of trauma, or baseline comorbidities. A total of 57% of controls versus 10% of patients with TEG-PM (p < 0.001) were transfused platelets; 52% of intervention patients and 0% controls were treated with DDAVP. Expansion hemorrhage volumes were not significantly different (14.0 cm³ [20.2] patients with TEG-PM versus 13.6 cm³ [23.7] controls; p = 0.93). There was no significant difference in rates of clinical deterioration, delayed neurosurgical intervention, or late platelet transfusion between groups.

CONCLUSIONS

Among patients with hemorrhagic TBI prescribed preinjury antiplatelet therapy, our study suggests that the use of a TEG-PM algorithm may reduce platelet transfusions without a concurrent increase in clinically significant hematoma expansion. Further study is required to prove a causative relationship.

Eastern Association for the Surgery of Trauma Multicenter Trial: Comparison of pre-injury antithrombotic use and reversal strategies among severe traumatic brain injury patients

BACKGROUND

Trauma teams are often faced with patients on antithrombotic (AT) drugs, which is challenging when bleeding occurs. We sought to compare the effects of different AT medications on head injury severity and hypothesized that AT reversal would not improve mortality in severe traumatic brain injury (TBI) patients.

METHODS

An Eastern Association for the Surgery of Trauma-sponsored prospective, multicentered, observational study of 15 trauma centers was performed. Patient demographics, injury burden, comorbidities, AT agents, and reversal attempts were collected. Outcomes of interest were head injury severity and in-hospital mortality.

RESULTS

Analysis was performed on 2,793 patients. The majority of patients were on aspirin (acetylsalicylic acid [ASA], 46.1%). Patients on a platelet chemoreceptor blocker (P2Y12) had the highest mean Injury Severity Score (9.1 ± 8.1). Patients taking P2Y12 inhibitors ± ASA, and ASA-warfarin had the highest head Abbreviated Injury Scale (AIS) mean (1.2 ± 1.6). On risk-adjusted analysis, warfarin-ASA was associated with a higher head AIS (odds ratio [OR], 2.43; 95% confidence interval [CI], 1.34-4.42) after controlling for Injury Severity Score, Charlson Comorbidity Index, initial Glasgow Coma Scale score, and initial systolic blood pressure. Among patients with severe TBI (head AIS score, ≥3) on antiplatelet therapy, reversal with desmopressin (DDAVP) and/or platelet transfusion did not improve survival (82.9% reversal vs. 90.4% none, p = 0.30). In severe TBI patients taking Xa inhibitors who received prothrombin complex concentrate, survival was not improved (84.6% reversal vs. 84.6% none, p = 0.68). With risk adjustment as described previously, mortality was not improved with reversal attempts (antiplatelet agents: OR 0.83; 85% CI, 0.12-5.9 [p = 0.85]; Xa inhibitors: OR, 0.76; 95% CI, 0.12-4.64; p = 0.77).

CONCLUSION

Reversal attempts appear to confer no mortality benefit in severe TBI patients on antiplatelet agents or Xa inhibitors. Combination therapy was associated with severity of head injury among patients taking preinjury AT therapy, with ASA-warfarin possessing the greatest risk.

LEVEL OF EVIDENCE

Prognostic, level II.

Management of stroke in patients on antithrombotic therapy: Practical issues in the era of direct oral anticoagulants

Antithrombotic drugs (ADs) are the mainstay of secondary prevention of thrombotic vascular diseases. Management of patients under long-term treatment with ADs admitted for acute cerebrovascular disease, either ischemic stroke (IS) or intracerebral hemorrhage (ICH), has become a frequent situation that might influence decision-making processes from diagnosis to therapeutic strategies. The aim of this review is to summarize current data from the literature to help clinicians in their decisions for stroke care in patients taking ADs. While a large body of data have made it possible to codify the management of patients presenting IS or ICH under antiplatelet drugs and vitamin K antagonists, the increasing use of direct oral anticoagulants (DOAs) and future development of new antiplatelet drugs raise new problems. Development of rapid assessment tools measuring specific biological activity and reversion agents dedicated to each class of DOAs should make it possible to optimize individual therapeutic strategies. This review highlights the main steps of IS and ICH management from early identification of ADs, and use of dedicated biological assays, to the stepwise strategy to apply revascularization or reversal therapies and finally the resumption of ADs with a focus on individual clinical and radiological characteristics for more personalized care.

Aspirin does not affect hematoma growth in severe spontaneous intracranial hematoma

Hematoma growth (HG) affects the prognosis of patients with spontaneous intracranial hematoma (ICH), but there is still a lack of evidence about the effects of aspirin (acetylsalicylic acid, ASA) on HG in patients with severe ICH. This study retrospectively analyzed patients with severe ICH who met the inclusion and exclusion criteria in Beijing Tiantan Hospital, Capital Medical University, between January 1, 2015, and July 31, 2019. Severe ICH patients were divided into ASA group and nASA groups according to ASA usage, and the incidence of HG between the groups was compared. Univariate analysis was performed by the Mann-Whitney U test, chi-square test, or Fisher exact test. Multivariate logistic regression analysis was used to analyze the impact of ASA on HG and to screen for risk factors of HG. In total, 221 patients with severe ICH were consecutively enrolled in this study. There were 72 (32.6%) patients in the ASA group and 149 patients in the nASA group. Although the incidence of HG in the nASA group was higher than that in the ASA group (34.9% VS 22.2%, p = 0.056), ASA did not significantly affect the occurrence of HG (p = 0.285) after adjusting for initial hematoma volume, high blood pressure at admission, coronary heart disease, and GCS at admission. In addition, we found that high blood pressure at admission was a risk factor for HG. Prior ASA does not increase the incidence of HG in severe ICH patients, and high blood pressure at admission is a risk factor for HG.

The Safety and Efficacy of Desmopressin in Patients With Intracranial Hemorrhage and a History of Alcohol Use

BACKGROUND

Patients with a history of alcohol use disorder are at an increased risk of hematoma expansion following intracranial hemorrhage (ICH) due to the effects of alcohol on platelet aggregation. Desmopressin (DDAVP) improves platelet aggregation and may decrease hematoma expansion in patients with ICH. However, DDAVP may also increase the risk of hyponatremia and thrombotic events. Evidence is limited regarding the safety and efficacy of DDAVP in alcohol use (AU)-associated ICH.

METHODS

This was a retrospective chart review of adult patients with radiographic evidence of ICH and a confirmed or suspected history of alcohol use upon admission. Patients were categorized into groups based on DDAVP administration. Safety outcomes included hyponatremia (serum sodium <135 mEq/L or decrease in serum sodium of ≥ 5 mEq/L for patients with baseline sodium <135 mEq/L) within 24 hours of ICH and thrombotic events within 7 days of ICH. The primary efficacy outcome was the incidence of hematoma expansion, defined as any expansion of the hemorrhage noted on repeat imaging within 32 hours.

RESULTS

In total, 52 patients were included in the safety analysis (27 DDAVP and 25 non-DDAVP). Although hyponatremia was numerically higher in the DDAVP group, there was no significant difference between groups (19.2% vs 4.2%, P = 0.192). Thrombotic complications were similar between the DDAVP and non-DDAVP groups (11.1% vs. 8%, P = 1.0). Thirty-nine patients met criteria for hemostatic efficacy analysis. There was no difference in hematoma expansion between the DDAVP and non-DDAVP groups (23.1% vs 34.6%, P = 0.71) and these findings were consistent after adjusting for differences in baseline characteristics (OR 0.63, 95% CI 0.1-3.3).

CONCLUSION

The administration of DDAVP was not associated with adverse safety events, but did not significantly reduce the incidence of hematoma expansion in patients with AU-associated ICH.

Indirect antiplatelet effects of rivaroxaban in a patient with intracranial hemorrhage: An underappreciated coagulopathy of factor Xa inhibitors?

Rivaroxaban is a direct oral anticoagulant (DOAC) used for prophylaxis and treatment of many prothrombotic states. The anticoagulation effects of rivaroxaban are produced by selectively binding and inhibiting factor Xa, causing delayed thrombin generation. Additionally, the delay in thrombin generation produces an indirect, dose dependent antiplatelet effect via reduction in tissue factor platelet aggregation. As with any anticoagulant, rivaroxaban use increases a patient's risk for major and minor hemorrhagic events. With mortality rates reported as high as 25% for those who experience an intracranial hemorrhage (ICH), immediate mitigation of hematoma and hemorrhage volume expansion is imperative. Management strategies include utilizing prothrombin complex concentrates (PCC) and factor Xa inhibitor specific antidotes, such as coagulation factor Xa recombinant, inactivated-zhzo. Routine monitoring or management of DOAC induced antiplatelet effects is ill-defined and not a part of routine standard of care. We report the first case, to our knowledge, of rivaroxaban's indirect antiplatelet effects identified by platelet function assays and managed with four-factor PCC and desmopressin in a patient experiencing an ICH. Further exploration is needed to determine the true clinical impact attributed to rivaroxaban's antiplatelet effects.

Pre-injury antithrombotic agents predict intracranial hemorrhagic progression, but not worse clinical outcome in severe traumatic brain injury

Background

The incidence of traumatic brain injury (TBI) patients of older age with comorbidities, who are pre-injury treated with antithrombotic agents (antiplatelets and/or anticoagulants), has increased. In this study, our aim was to investigate if pre-injury antithrombotic treatment was associated with worse intracranial hemorrhagic/injury progression and clinical outcome in patients with severe TBI.

Methods

In this retrospective study, including 844 TBI patients treated at our neurointensive care at Uppsala University Hospital, Sweden, 2008–2018, 159 (19%) were pre-injury treated with antithrombotic agents. Demography, admission status, radiology, treatment, and outcome variables were evaluated. Significant intracranial hemorrhagic/injury evolution was defined as hemorrhagic progression seen on the second computed tomography (CT), emergency neurosurgery after the initial CT, or death following the initial CT.

Results

Patients with pre-injury antithrombotics were significantly older and with a higher Charlson comorbidity index. They were more often injured by falls and more frequently developed acute subdural hematomas. Sixty-eight (8%) patients were pre-injury treated with monotherapy of antiplatelets, 67 (8%) patients with anticoagulants, and 24 (3%) patients with a combination of antithrombotics. Pre-injury anticoagulants, but not antiplatelets, were independently associated with significant intracranial hemorrhagic/injury evolution in a multiple regression analysis. However, neither anticoagulants nor antiplatelets were associated with mortality and unfavorable outcome in multiple regression analyses.

Conclusions

Only anticoagulants were associated with intracranial hemorrhagic/injury progression, but no antithrombotic agent correlated with worse clinical outcome. Management, including early anticoagulant reversal, availability of emergency neurosurgery, and neurointensive care, may be important aspects for reducing the adverse effects of pre-injury antithrombotics.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00701-021-04816-0.

The Effect of Antithrombotics on Hematoma Expansion in Small- to Moderate-Sized Traumatic Intraparenchymal Hemorrhages

BACKGROUND

Although pre-injury antithrombotic agents, including antiplatelets and anticoagulants, are historically associated with expansion of traumatic intraparenchymal hemorrhage (tIPH), the literature has poorly elucidated the actual risk of hematoma expansion on repeat computed tomography (CT). The objective was to determine the effect of antithrombotic agents on hematoma expansion in tIPH by comparing patients with and without pre-injury antithrombotic medication.

METHODS

The volume of all tIPHs over a 5-year period at an academic Level 1 trauma center was measured retrospectively. The initial tIPH was divided into 3 equally sized quantiles. The third tercile, representing the largest subset of tIPH, was then removed from the study population because these patients reflect a different pathophysiologic mechanism that may require a more acute and aggressive level of care with reversal agents and/or operative management. Per institutional policy, all patients with small- to moderate-sized hemorrhages received a 24-hour stability CT scan. Patients who received reversal agents were excluded.

RESULTS

Of the 105 patients with a tIPH on the initial head CT scan, small- to moderate-sized hemorrhages were <5 cm³. The size of tIPH on initial imaging did not statistically significantly differ between the antithrombotic cohort (0.7 ± 0.1 cm³) and the non-antithrombotic cohort (0.5 ± 0.1 cm³) (P = 0.091). Similarly, the volume of tIPH failed to differ on 24-hour repeat imaging (1.0 ± 0.2 cm³ vs. 0.6 ± 0.1 cm³, respectively, P = 0.172). Following a multiple linear regression, only history of stroke, not antithrombotic medications, predicted increased tIPH on 24-hour repeat imaging.

CONCLUSIONS

In small- to moderate-sized tIPH, withholding antithrombotic agents without reversal may be sufficient.

Platelet Dysfunction after Traumatic Brain Injury: A Review

Coagulopathy is a known sequela of traumatic brain injury (TBI) and can lead to increased morbidity and mortality. Platelet dysfunction has been identified as one of several etiologies of coagulopathy following TBI and has been associated with poor outcomes. Regardless of whether the platelet dysfunction occurs as a direct consequence of the injury or because of pre-existing medical comorbidities or medication use, accurate detection and monitoring of response to therapy is key to optimal patient care. Platelet transfusion has been proposed as a potential therapeutic intervention to treat platelet dysfunction, with several studies using platelet function assays to monitor response. The development of increasingly precise diagnostic testing is providing enhanced understanding of the specific derangement in the hemostatic process, allowing clinicians to provide patient-specific treatment plans. There is wide variability in the currently available literature on the incidence and clinical significance of platelet dysfunction following TBI, which creates challenges with developing evidence-based management guidelines. The relatively high prevalence of platelet inhibitor therapy serves as an additional confounding factor. In addition, the data are largely retrospective in nature. We performed a literature review to provide clarity on this clinical issue. We reviewed 348 abstracts, and included 97 manuscripts in our final literature review. Based on the currently available research, platelet dysfunction has been consistently demonstrated in patients with moderate-severe TBI. We recommend the use of platelet functional assays to evaluate patients with TBI. Platelet transfusion directed at platelet dysfunction may lead to improved clinical outcome. A randomized trial guided by implementation science could improve the applicability of these practices.

Effect of Desmopressin on Platelet Dysfunction During Antiplatelet Therapy: A Systematic Review

BACKGROUND AND OBJECTIVE

An increasing number of patients receive antiplatelet therapy. Patients exposed to surgery while receiving platelet inhibitors hold an increased bleeding risk. Especially in neurosurgery and neurocritical care patients, bleeding and hematoma expansion are feared complications as even minor bleedings may be hazardous. The objective of this systematic review was to investigate the effect of desmopressin (1-deamino-8-D-arginine vasopressin, DDAVP) on platelet function during antiplatelet therapy in patients undergoing non-cardiac surgery, patients who experience spontaneous or traumatic hemorrhage, healthy individuals and in animals.

METHODS

Studies were identified through a systematic literature search in PubMed and EMBASE on August 19, 2019, with an update on May 2, 2020, and from reference lists of the included studies. Data on clinical and biochemical effect of DDAVP were extracted from included studies for a qualitative data synthesis.

RESULTS

In total, 22 studies were included: 18 human studies and four animal studies. Overall, DDAVP improved bleeding time and increased platelet aggregation in patients undergoing non-cardiac surgery, patients suffering intracerebral or subarachnoid hemorrhage while receiving antiplatelet therapy as well as in healthy individuals and animals exposed to antiplatelet therapy. Observational data indicate that DDAVP may mitigate hematoma expansion in patients with intracerebral hemorrhage or traumatic brain injury.

CONCLUSIONS

The present data hold biochemical evidence that DDAVP improves platelet function during antiplatelet therapy in humans and animals. The need for randomized trials is evident in order to evaluate the potential clinical effect of DDAVP in management of patients with spontaneous or traumatic hemorrhage, or undergoing neurosurgery, while receiving antiplatelet therapy.