Safety of early pharmacological thromboprophylaxis after subarachnoid hemorrhage

Emergent Management of Spontaneous Subarachnoid Hemorrhage

OBJECTIVE

Spontaneous subarachnoid hemorrhage (SAH) carries high morbidity and mortality rates, and the emergent management of this disease can make a large impact on patient outcome. The purpose of this article is to provide a pragmatic overview of the emergent management of SAH.

LATEST DEVELOPMENTS

Recent trials have influenced practice around the use of antifibrinolytics, the timing of aneurysm securement, the recognition of cerebral edema and focus on avoiding a lower limit of perfusion, and the detection and prevention of delayed cerebral ischemia. Much of the acute management of SAH can be protocolized, as demonstrated by two updated guidelines published by the American Heart Association/American Stroke Association and the Neurocritical Care Society in 2023. However, the gaps in evidence lead to clinical equipoise in some aspects of critical care management.

ESSENTIAL POINTS

In acute management, there is an urgency to differentiate the etiology of SAH and take key emergent actions including blood pressure management and coagulopathy reversal. The critical care management of SAH is similar to that of other acute brain injuries, with the addition of detecting and treating delayed cerebral ischemia. Strategies for the detection and treatment of delayed cerebral ischemia are limited by disordered consciousness and may be augmented by monitoring and imaging technology.

Diagnosis and management of subarachnoid haemorrhage

Aneurysmal subarachnoid haemorrhage (aSAH) presents a challenge to clinicians because of its multisystem effects. Advancements in computed tomography (CT), endovascular treatments, and neurocritical care have contributed to declining mortality rates. The critical care of aSAH prioritises cerebral perfusion, early aneurysm securement, and the prevention of secondary brain injury and systemic complications. Early interventions to mitigate cardiopulmonary complications, dyselectrolytemia and treatment of culprit aneurysm require a multidisciplinary approach. Standardised neurological assessments, transcranial doppler (TCD), and advanced imaging, along with hypertensive and invasive therapies, are vital in reducing delayed cerebral ischemia and poor outcomes. Health care disparities, particularly in the resource allocation for SAH treatment, affect outcomes significantly, with telemedicine and novel technologies proposed to address this health inequalities. This article underscores the necessity for comprehensive multidisciplinary care and the urgent need for large-scale studies to validate standardised treatment protocols for improved SAH outcomes.

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

INTRODUCTION

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage: A Guideline From the American Heart Association/American Stroke Association

AIM

The "2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage" replaces the 2012 "Guidelines for the Management of Aneurysmal Subarachnoid Hemorrhage." The 2023 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with aneurysmal subarachnoid hemorrhage.

METHODS

A comprehensive search for literature published since the 2012 guideline, derived from research principally involving human subjects, published in English, and indexed in MEDLINE, PubMed, Cochrane Library, and other selected databases relevant to this guideline, was conducted between March 2022 and June 2022. In addition, the guideline writing group reviewed documents on related subject matter previously published by the American Heart Association. Newer studies published between July 2022 and November 2022 that affected recommendation content, Class of Recommendation, or Level of Evidence were included if appropriate. Structure: Aneurysmal subarachnoid hemorrhage is a significant global public health threat and a severely morbid and often deadly condition. The 2023 aneurysmal subarachnoid hemorrhage guideline provides recommendations based on current evidence for the treatment of these patients. The recommendations present an evidence-based approach to preventing, diagnosing, and managing patients with aneurysmal subarachnoid hemorrhage, with the intent to improve quality of care and align with patients' and their families' and caregivers' interests. Many recommendations from the previous aneurysmal subarachnoid hemorrhage guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Incidence and Risk Model of Venous Thromboembolism in Patients with Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

Venous thromboembolism (VTE) is a significant source of morbidity and mortality in hospitalized patients. We describe our experience with VTE prophylaxis and treatment in patients with aneurysmal subarachnoid hemorrhage (aSAH), risk factors for VTE, and a hazard model describing the daily risk of VTE.

METHODS

A retrospective cohort study was performed on patients with aSAH admitted from 2014 to 2018. Patients were screened for VTE based on clinical suspicion. Demographics, perioperative data, and in-hospital data were assessed as risk factors for VTE using survival analysis with death as a competing risk.

RESULTS

Among 485 patients, the overall incidence of VTE, deep vein thrombosis, and pulmonary embolism were 5.6%, 4.3%, and 2.3%, respectively. Increasing length of stay in the intensive care unit (hazard ratio [HR], 1.79; P < 0.0001; 95% confidence interval [CI], 1.49-2.16) and ventilation immediately after aneurysm treatment was associated with VTE (HR, 8.87; P < 0.01; 95% CI, 1.86-42.38). Hunt and Hess grade was negatively associated with VTE (HR, 0.61; P = 0.045; 95% CI, 0.37-1.00) due to its increased association with the competing risk of death (HR, 2.57; P < 0.0001; 95% CI, 1.89-3.49). The adjusted 4-year cumulative incidence for VTE is 11.1% and at mean day of hospital discharge is 5.4%. Treatment of VTEs with anticoagulation and/or inferior vena cava filter placement was not associated with immediate complications.

CONCLUSIONS

We describe the largest single-institution cohort of VTEs in aSAH patients. Our hazard model quantifies the cumulative incidence of VTEs during the course of hospitalization. We suggest a standardized protocol for screening, prophylaxis, and treatment of VTEs in this patient population.

Spontaneous subarachnoid haemorrhage

Subarachnoid haemorrhage (SAH) is the third most common subtype of stroke. Incidence has decreased over past decades, possibly in part related to lifestyle changes such as smoking cessation and management of hypertension. Approximately a quarter of patients with SAH die before hospital admission; overall outcomes are improved in those admitted to hospital, but with elevated risk of long-term neuropsychiatric sequelae such as depression. The disease continues to have a major public health impact as the mean age of onset is in the mid-fifties, leading to many years of reduced quality of life. The clinical presentation varies, but severe, sudden onset of headache is the most common symptom, variably associated with meningismus, transient or prolonged unconsciousness, and focal neurological deficits including cranial nerve palsies and paresis. Diagnosis is made by CT scan of the head possibly followed by lumbar puncture. Aneurysms are commonly the underlying vascular cause of spontaneous SAH and are diagnosed by angiography. Emergent therapeutic interventions are focused on decreasing the risk of rebleeding (ie, preventing hypertension and correcting coagulopathies) and, most crucially, early aneurysm treatment using coil embolisation or clipping. Management of the disease is best delivered in specialised intensive care units and high-volume centres by a multidisciplinary team. Increasingly, early brain injury presenting as global cerebral oedema is recognised as a potential treatment target but, currently, disease management is largely focused on addressing secondary complications such as hydrocephalus, delayed cerebral ischaemia related to microvascular dysfunction and large vessel vasospasm, and medical complications such as stunned myocardium and hospital acquired infections.

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

Background

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

Methods

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

Results

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

Conclusions

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

Hemorrhage Rate After External Ventricular Drain Placement in Subarachnoid Hemorrhage: Time to Heparin Administration

OBJECTIVE

The use of antiplatelet or anticoagulants has previously been shown to increase hemorrhagic complications of ventricular catheterization. Although heparin use 24 h after ventriculostomy appears safe, the safety of heparin immediately (within 4 h) after ventriculostomy is unknown. The objective of this study was to assess the safety of heparin immediately (within 4 h) after ventriculostomy in subarachnoid hemorrhage (SAH) patients undergoing endovascular treatment.

PATIENTS AND METHODS

This is a retrospective cohort study of 46 patients with aneurysmal SAH secondary to aneurysm rupture who required ventriculostomy. Post-ventriculostomy imaging was carefully reviewed for tract hemorrhaging. Timing of heparinization was noted. Early heparinization was within 4 h after ventriculostomy, and intermediate heparinization was between 4 and 24 h after ventriculostomy.

RESULTS

Overall, the tract hemorrhage rate was 26.1% for the study cohort-mostly grade I tract hemorrhages-consistent with the existing literature. The tract hemorrhage rate in the early (<4 h) heparin group was a remarkable 58.8%. The hemorrhages were also notably larger in the early (<4 h) heparin group.

CONCLUSION

Although heparin appears to be safe after 4 h, immediate heparinization (within 4 h) after ventriculostomy significantly increases the odds of tract hemorrhage. Additional time should be afforded between ventriculostomy and heparinization to avoid potentially devastating external ventricular drain tract hemorrhage. It is advisable to wait a sufficient time (at least 4 h) after ventriculostomy before embarking on endovascular treatment of ruptured aneurysms.

Low-Dose versus Therapeutic Range Intravenous Unfractionated Heparin Prophylaxis in the Treatment of Patients with Severe Aneurysmal Subarachnoid Hemorrhage After Aneurysm Occlusion

BACKGROUND

While prophylaxis with intravenous unfractionated heparin (UFH) can effectively prevent venous thromboembolism (VTE) during the neurocritical care of patients with severe aneurysmal subarachnoid hemorrhage (aSAH), the risk for intracranial bleeding complications might increase. Owing to this therapeutic dilemma, the UFH administration regimen in this critical patient population remains highly controversial.

METHODS

We performed a retrospective analysis of patients with severe aSAH (Fisher grade 3-4) receiving either low-dose (activated partial thromboplastin time [aPTT] <40 seconds) or therapeutic range (aPTT 50-60 seconds) UFH during intensive care unit (ICU) treatment after complete surgical/endovascular aneurysm occlusion. The primary outcome was the rate of bleeding/VTE complications and the investigation of potential risk factors.

RESULTS

This study series comprised 410 patients with aneurysmal SAH (aSAH), with a mean age of 54.7 ± 12.6 years, a male:female ratio of 1:2.2, and aSAH-associated intracerebral hemorrhage (ICH) in 33.2%. After complete aneurysm occlusion, 112 patients (27.3%) received therapeutic dose UFH and 298 patients (72.7%) received low-dose UFH. VTE events occurred in 5.4% of the low-dose UFH cohort and in 6.3% of the therapeutic dose UFH cohort, with no significant differences in the rate and severity of VTE events. However, an increase in initial SAH-associated ICH was significantly (P = 0.007) more frequent in the therapeutic dose cohort (18.8% vs. 3.4%). Heparin-induced thrombocytopenia (HIT) was the sole risk factor for VTE (P < 0.001), and both an aPTT ≥50 seconds under UFH administration (P = 0.007) and the initial presence of SAH-associated ICH (P = 0.035) were significant risk factors for intracranial bleeding complications.

CONCLUSIONS

Even in high-risk neurocritical patients with severe SAH and prolonged ICU treatment, low-dose UFH-administration for VTE prophylaxis is equally effective as therapeutic UFH administration and carries a lower risk of bleeding complications.

Perimesencephalic subarachnoid hemorrhage with a positive angiographic finding: case report and review of the literature

The vast majority of perimesencephalic subarachnoid hemorrhage cases are reported as negative-finding etiologies. Recently, high-resolution images allowed us to overcome the previous difficulty of finding the source of bleeding, which underlies the concept of a "negative finding". We discovered a venous etiology, hidden behind the tip of the basilar artery; namely, the lateral pontine vein. Here, we review the literature on perimesencephalic subarachnoid hemorrhage and on venous aneurysm. We highlight this type of aneurysm as a candidate source of perimesencephalic hemorrhage. This case may change our way of dealing with what we have termed a negative finding of subarachnoid hemorrhage.

The critical care management of poor-grade subarachnoid haemorrhage

Aneurysmal subarachnoid haemorrhage is a neurological syndrome with complex systemic complications. The rupture of an intracranial aneurysm leads to the acute extravasation of arterial blood under high pressure into the subarachnoid space and often into the brain parenchyma and ventricles. The haemorrhage triggers a cascade of complex events, which ultimately can result in early brain injury, delayed cerebral ischaemia, and systemic complications. Although patients with poor-grade subarachnoid haemorrhage (World Federation of Neurosurgical Societies 4 and 5) are at higher risk of early brain injury, delayed cerebral ischaemia, and systemic complications, the early and aggressive treatment of this patient population has decreased overall mortality from more than 50% to 35% in the last four decades. These management strategies include (1) transfer to a high-volume centre, (2) neurological and systemic support in a dedicated neurological intensive care unit, (3) early aneurysm repair, (4) use of multimodal neuromonitoring, (5) control of intracranial pressure and the optimisation of cerebral oxygen delivery, (6) prevention and treatment of medical complications, and (7) prevention, monitoring, and aggressive treatment of delayed cerebral ischaemia. The aim of this article is to provide a summary of critical care management strategies applied to the subarachnoid haemorrhage population, especially for patients in poor neurological condition, on the basis of the modern concepts of early brain injury and delayed cerebral ischaemia.