A Survey on Monitoring and Management of Cerebral Vasospasm and Delayed Cerebral Ischemia After Subarachnoid Hemorrhage: The Mantra Study

Nimodipine in Aneurysmal Subarachnoid Hemorrhage: Are Old Data Enough to Justify Its Current Treatment Regimen?

Nimodipine, a dihydropyridine L-type calcium channel antagonist, constitutes one of the mainstays of care to prevent delayed cerebral ischemia in patients with aneurysmal subarachnoid hemorrhage (aSAH) because it has been associated with a reduction in infarction rates and improvement in functional outcomes despite not significantly preventing angiographic vasospasm. Although it is a widely accepted treatment, controversies surrounding the current regimen of nimodipine in patients with aSAH exist. Still, there is a wide space open for randomized controlled trials or alternative study designs comparing different routes of administration, dosing, and timing of nimodipine treatment regimen in patients with aSAH.

Individualized autoregulation-guided arterial blood pressure management in neurocritical care

Cerebral autoregulation (CA) is the physiological process by which cerebral blood flow is maintained during fluctuations in arterial blood pressure (ABP). There are various validated methods to measure CA, either invasively, with intracranial pressure or brain tissue oxygenation monitors, or noninvasively, with transcranial Doppler ultrasound or near-infrared spectroscopy. Utilizing these monitors, researchers have been able to discern CA patterns in several pathological states, such as but not limited to acute ischemic stroke, spontaneous intracranial hemorrhage, aneurysmal subarachnoid hemorrhage, sepsis, and post-cardiac arrest, and they have found CA to be altered in these patients. CA disturbances predispose patients suffering from these ailments to worse outcomes. Much focus has been placed on CA monitoring in these populations, with an emphasis on arterial blood pressure optimization. Many guidelines recommend universal static ABP targets; however, in patients with altered CA, these targets may make them susceptible to hypoperfusion and further neurological injury. Based on this observation, there has been much investigation on individualized ABP goals and their effect on clinical outcomes. The scope of this review includes (1) a summary of the physiology of CA in healthy adults; (2) a review of the evidence on CA monitoring in healthy individuals; (3) a summary of CA changes and its effect on outcomes in various diseased states including acute ischemic stroke, spontaneous intracranial hemorrhage, aneurysmal subarachnoid hemorrhage, sepsis and meningitis, post-cardiac arrest, hypoxic-ischemic encephalopathy, surgery, and moyamoya disease; and (4) a review of the current evidence on individualized ABP changes in various patient populations.

Diagnosis and endovascular management of vasospasm after aneurysmal subarachnoid hemorrhage - survey of real-life practices

BACKGROUND

Vasospasm and delayed cerebral ischemia (DCI) are the leading causes of morbidity and mortality after intracranial aneurysmal subarachnoid hemorrhage (aSAH). Vasospasm detection, prevention and management, especially endovascular management varies from center to center and lacks standardization. We aimed to evaluate this variability via an international survey of how neurointerventionalists approach vasospasm diagnosis and endovascular management.

METHODS

We designed an anonymous online survey with 100 questions to evaluate practice patterns between December 2021 and September 2022. We contacted endovascular neurosurgeons, neuroradiologists and neurologists via email and via two professional societies - the Society of NeuroInterventional Surgery (SNIS) and the European Society of Minimally Invasive Neurological Therapy (ESMINT). We recorded the physicians' responses to the survey questions.

RESULTS

A total of 201 physicians (25% [50/201] USA and 75% non-USA) completed the survey over 10 months, 42% had >7 years of experience, 92% were male, median age was 40 (IQR 35-46). Both high-volume and low-volume centers were represented. Daily transcranial Doppler was the most common screening method (75%) for vasospasm. In cases of symptomatic vasospasm despite optimal medical management, endovascular treatment was directly considered by 58% of physicians. The most common reason to initiate endovascular treatment was clinical deficits associated with proven vasospasm/DCI in 89%. The choice of endovascular treatment and its efficacy was highly variable. Nimodipine was the most common first-line intra-arterial therapy (40%). Mechanical angioplasty was considered the most effective endovascular treatment by 65% of neurointerventionalists.

CONCLUSION

Our study highlights the considerable heterogeneity among the neurointerventional community regarding vasospasm diagnosis and endovascular management. Randomized trials and guidelines are needed to improve standard of care, determine optimal management approaches and track outcomes.

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.

Effects of induced arterial hypertension for vasospasm on unruptured and unsecured cerebral aneurysms (growth and rupture). A retrospective case-control study

OBJECTIVES

Unruptured cerebral aneurysms (UCAs) often coexist with the ruptured one but are typically left unsecured during the weeks following aneurysmal subarachnoid hemorrhage (aSAH). We compared the rate of UCAs rupture or volume growth (≥5 mm3) between patients exposed to induced arterial hypertension (iHTN) for vasospasm and those not exposed (control group).

MATERIALS AND METHODS

From 2013 to 2021, we retrospectively included consecutive adult patients with aSAH who had ≥1 UCA. Custom software for digital subtraction angiography (DSA) image analysis characterized UCAs volume, going beyond merely considering UCAs long axis.

RESULTS

We analyzed 118 patients (180 UCAs): 45 in the iHTN group (64 UCAs) and 73 in the control group (116 UCAs). Systolic blood pressure in the iHTN group was significantly higher than in the control group for several days after aSAH. During the 107 day-monitoring period [interquartile range(IQR):92;128], no UCA rupture occurred in either group. UCA volume analysis was performed in 44 patients (60 UCAs): none of the UCAs in the iHTN group and 3 out of 42 (7%) in the control group had a >5 mm3 volume growth (p=0.55). Other morphologic parameters did not exhibit any variations that might indicate an increased risk of rupture in the iHTN group compared to the control group.

CONCLUSION

iHTN did not increase the risk of rupture or volume growth of UCAs within several weeks following aSAH. These reassuring results encourage not to refrain, because of the existence of UCAs, from iHTN as an option to prevent cerebral infarction during cerebral vasospasm.

Contemporary management of aneurysmal subarachnoid haemorrhage. An update for the intensivist

Aneurysmal subarachnoid haemorrhage (aSAH) is a rare yet profoundly debilitating condition associated with high global case fatality and morbidity rates. The key determinants of functional outcome include early brain injury, rebleeding of the ruptured aneurysm and delayed cerebral ischaemia. The only effective way to reduce the risk of rebleeding is to secure the ruptured aneurysm quickly. Prompt diagnosis, transfer to specialized centers, and meticulous management in the intensive care unit (ICU) significantly improved the prognosis of aSAH. Recently, multimodality monitoring with specific interventions to correct pathophysiological imbalances has been proposed. Vigilance extends beyond intracranial concerns to encompass systemic respiratory and haemodynamic monitoring, as derangements in these systems can precipitate secondary brain damage. Challenges persist in treating aSAH patients, exacerbated by a paucity of robust clinical evidence, with many interventions showing no benefit when tested in rigorous clinical trials. Given the growing body of literature in this field and the issuance of contemporary guidelines, our objective is to furnish an updated review of essential principles of ICU management for this patient population. Our review will discuss the epidemiology, initial stabilization, treatment strategies, long-term prognostic factors, the identification and management of post-aSAH complications. We aim to offer practical clinical guidance to intensivists, grounded in current evidence and expert clinical experience, while adhering to a concise format.

Twelve controversial questions in aneurysmal subarachnoid hemorrhage

Critical care management of aneurysmal subarachnoid hemorrhage (aSAH) remains a major challenge. Despite the recent publication of guidelines from the American Heart Association/American Stroke Association and the Neurocritical Care Society, there are many controversial questions in the intensive care unit (ICU) management of this population. The authors provide an analysis of common issues in the ICU and provide guidance on the daily management of this specific population of neurocritical care patients.

Cerebral Vasospasm After Subarachnoid Hemorrhage: Respective Short-Term Effects of Induced Arterial Hypertension and its Combination With IV Milrinone: A Proof-of-Concept Study Using Transcranial Doppler Ultrasound

OBJECTIVES

It is unclear whether IV milrinone relaxes spasmed cerebral arteries and therefore reduces cerebral blood mean velocity (Vmean). In patients treated for cerebral vasospasm, we aimed to assess and delineate the respective impacts of induced hypertension and its combination with IV milrinone on cerebral hemodynamics as assessed with transcranial Doppler.

DESIGN

Observational proof-of-concept prospective study.

SETTING

ICU in a French tertiary care center.

PATIENTS

Patients with aneurysmal subarachnoid hemorrhage who received induced hypertension (mean arterial blood pressure [MBP] of 100-120 mm Hg) and IV milrinone (0.5 µg/kg/min) for moderate-to-severe cerebral vasospasm. We excluded patients who underwent invasive angioplasty or milrinone discontinuation within 12 hours after the diagnosis of vasospasm.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Vmean was measured at vasospasm diagnosis (TDIAGNOSIS), after the induction of hypertension (THTN), and 1 (THTN+MILRINONE_H1) and 12 hours after the adjunction of IV milrinone (THTN+MILRINONE_H12). Thirteen patients were included. Median Vmean was significantly lower (p < 0.01) at THTN+MILRINONE_H1 (99 [interquartile range (IQR) 89; 134] cm.s-1) and THTN+MILRINONE_H12 (85 [IQR 73-127] cm/s) than at TDIAGNOSIS (136 [IQR 115-164] cm/s) and THTN (148 [IQR 115-183] cm/s), whereas TDIAGNOSIS and THTN did not significantly differ. In all patients but one, Vmean at THTN+MILRINONE_H1 was lower than its value at TDIAGNOSIS (p = 0.0005). Vmean-to-MBP and Vmean-to-cardiac output (CO) ratios (an assessment of Vmean regardless of the level of MBP [n = 13] or CO [n = 7], respectively) were, respectively, similar at TDIAGNOSIS and THTN but were significantly lower after the adjunction of milrinone (p < 0.01).

CONCLUSIONS

The induction of arterial hypertension was not associated with a significant decrease in Vmean, whereas the adjunction of IV milrinone was, regardless of the level of MBP or CO. This suggests that IV milrinone may succeed in relaxing spasmed arteries.