Evolucollateral dynamics in stroke: Evolutionary pathophysiology, remodelling and emerging therapeutic strategies

Leptomeningeal collaterals (LMCs) are crucial in mitigating the impact of acute ischemic stroke (AIS) by providing alternate blood flow routes when primary arteries are obstructed. This article explores the evolutionary pathophysiology of LMCs, highlighting their critical function in stroke and the genetic and molecular mechanisms governing their development and remodelling. We address the translational challenges of applying animal model findings to human clinical scenarios, emphasizing the need for further research to validate emerging therapies-such as pharmacological agents, gene therapy and mechanical interventions-in clinical settings, aimed at enhancing collateral perfusion. Computational modelling emerges as a promising method for integrating experimental data, which requires precise parameterization and empirical validation. We introduce the 'Evolucollateral Dynamics' hypothesis, proposing a novel framework that incorporates evolutionary biology principles into therapeutic strategies, offering new perspectives on enhancing collateral circulation. This hypothesis emphasizes the role of genetic predispositions and environmental influences on collateral circulation, which may impact therapeutic strategies and optimize treatment outcomes. Future research must incorporate human clinical data to create robust treatment protocols, thereby maximizing the therapeutic potential of LMCs and improving outcomes for stroke patients.

Trendelenburg position for acute anterior circulation ischaemic stroke with large artery atherosclerosis aetiology (HOPES 3): rationale and design

RATIONALE

The effect of the head position as a non-pharmacological therapy on acute ischaemic stroke (AIS) remains inconclusive. Our recent Head dOwn-Position for acutE moderate ischaemic Stroke with large artery atherosclerosis (HOPES 2) suggested the safety, feasibility and potential benefit of the head-down position (HDP) in AIS.

AIM

To investigate the benefit of HDP in acute moderate ischaemic stroke patients with large artery atherosclerosis (LAA).

SAMPLE SIZE ESTIMATES

Based on a two-sided 0.05 level of significance, 600 patients are expected to yield the superiority hypothesis with 80% power, stratified by age, sex, history of diabetes, baseline systolic blood pressure, location of index vessel, National Institutes of Health Stroke Scale Score at randomisation, onset to randomisation time, progression to moderate neurological deficit due to early neurological deterioration and degree of responsible vessel stenosis.

DESIGN

Head dOwn-Position for acutE moderate ischaemic Stroke with large artery atherosclerosis(HOPES 3) is a prospective, randomised, open-label, blinded endpoint and multicentre study. Eligible patients who had an ischaemic stroke will be randomly assigned (1:1) into the HDP group receiving -20° Trendelenburg plus standard medical care in compliance with national guidelines, or control group only receiving standard medical care in compliance with national guidelines.

OUTCOME

The primary outcome is favourable functional outcome, defined as modified Rankin Scale 0-2 at 90 days. Safety outcomes are HDP-related adverse events. All outcomes will have blinded assessment and will be analysed on the intention-to-treat basis.

CONCLUSIONS

The results of HOPES 3 will provide evidence for the effect of HDP in acute moderate ischaemic stroke patients with LAA within 24 hours of onset or in patients with progression from mild neurological deficit within 24 hours.

TRIAL REGISTRATION NUMBER

NCT06010641.

Efficacy and safety of very early rehabilitation for acute ischemic stroke: a systematic review and meta-analysis

Background

Early rehabilitation after acute ischemic stroke (AIS) contributes to functional recovery. However, the optimal time for starting rehabilitation remains a topic of ongoing investigation. This article aims to shed light on the safety and efficacy of very early rehabilitation (VER) initiated within 48 h of stroke onset.

Methods

A systematic search in PubMed, Embase, Cochrane Library, and Web of Science databases was conducted from inception to January 20, 2024. Relevant literature on VER in patients with AIS was reviewed and the data related to favorable and adverse clinical outcomes were collected for meta-analysis. Subgroup analysis was conducted at different time points, namely at discharge and at three and 12 months. Statistical analyses were performed with the help of the Meta Package in STATA Version 15.0.

Results

A total of 14 randomized controlled trial (RCT) studies and 3,039 participants were included in the analysis. VER demonstrated a significant association with mortality [risk ratio (RR) = 1.27, 95% confidence interval (CI) (1.00, 1.61)], ability of daily living [weighted mean difference (WMD) = 6.90, 95% CI (0.22, 13.57)], and limb motor function [WMD = 5.02, 95% CI (1.63, 8.40)]. However, no significant difference was observed between the VER group and the control group in adverse events [RR = 0.89, 95% CI (0.79, 1.01)], severity of stroke [WMD = 0.52, 95% CI (-0.04, 1.08)], degree of disability [RR = 1.06, 95% CI (0.93, 1.20)], or recovery of walking [RR = 0.98, 95% CI (0.94, 1.03)] after stroke. Subgroup analysis revealed that VER reduced the risk of adverse events in the late stage (at three and 12 months) [RR = 0.86, 95% CI (0.74, 0.99)] and degree of disability at 12 months [RR = 1.28, 95% CI (1.03, 1.60)], and improved daily living ability at 3 months [WMD = 4.26, 95% CI (0.17, 8.35)], while increasing severity of stroke during hospitalization [WMD = 0.81, 95% CI (0.01, 1.61)].

Conclusion

VER improves activities of daily living (ADLs) and lowers the incidence of long-term complications in stroke survivors. However, premature or overly intense rehabilitation may increase mortality in patients with AIS during the acute phase. PROSPERO registration number: CRD42024508180.

Systematic review registration

This systematic review was registered with PROSPERO (https://www.crd.york.ac.uk/PROSPERO/). PROSPERO registration number: CRD42024508180.

Study of Time-Resolved Dynamics in Turbid Medium Using a Single-Cavity Dual-Comb Laser

In measuring cerebral blood flow (CBF) noninvasively using optical techniques, diffusing-wave spectroscopy is often combined with near-infrared spectroscopy to obtain a reliable blood flow index. Measuring the blood flow index at a determined depth remains the ultimate goal. In this study, we present a simple approach using dual-comb lasers where we simultaneously measure the absorption coefficient (μa), the reduced scattering coefficient (μs '), and dynamic properties. This system can also effectively differentiate dynamics from various depths, which is crucial for analyzing multilayer dynamics. For CBF measurements, this capability is particularly valuable as it helps mitigate the influence of the scalp and skull, thereby enhancing the specificity of deep tissue.

Cerebral hemodynamic response to upright position in acute ischemic stroke

Introduction

Concerns exist that a potential mechanism for harm from upright activity (sitting, standing, and walking) early after an acute ischaemic stroke could be the reduction of cerebral perfusion during this critical phase. We aimed to estimate the effects of upright positions (sitting and standing) on cerebral hemodynamics within 48 h and later, 3-7 days post-stroke, in patients with strokes with and without occlusive disease and in controls.

Methods

We investigated MCAv using transcranial Doppler in 0° head position, then at 30°, 70°, 90° sitting, and 90° standing, at <48 h post-stroke, and later at 3-7 days post-stroke. Mixed-effect linear regression modeling was used to estimate differences in MCAv between the 0° and other positions and to compare MCAv changes across groups.

Results

A total of 42 stroke participants (anterior and posterior circulation) (13 with occlusive disease, 29 without) and 22 controls were recruited. Affected hemisphere MCAv decreased in strokes with occlusive disease (<48 h post-stroke): from 0° to 90° sitting (-9.9 cm/s, 95% CI[-16.4, -3.4]) and from 0° to 90° standing (-7.1 cm/s, 95%CI[-14.3, -0.01]). Affected hemisphere MCAv also decreased in strokes without occlusive disease: from 0° to 90° sitting (-3.3 cm/s, 95%CI[-5.6, -1.1]) and from 0° to 90° standing (-3.6 cm/s, 95%CI [-5.9, -1.3]) (p-value interaction stroke with vs. without occlusive disease = 0.07). A decrease in MCAv when upright was also observed in controls: from 0° to 90° sitting (-3.8 cm/s, 95%CI[-6.0, -1.63]) and from 0° to 90° standing (-3 cm/s, 95%CI[-5.2, -0.81]) (p-value interaction stroke vs. controls = 0.85). Subgroup analysis of anterior circulation stroke showed similar patterns of change in MCAv in the affected hemisphere, with a significant interaction between those with occlusive disease (n = 11) and those without (n = 26) (p = 0.02). Changes in MCAv from 0° to upright at <48 h post-stroke were similar to 3-7 days. No association between changes in MCAv at <48 h and the 30-day modified Rankin Scale was found.

Discussion

Moving to more upright positions <2 days post-stroke does reduce MCAv in the affected hemisphere; however, these changes were not significantly different for stroke participants (anterior and posterior circulation) with and without occlusive disease, nor for controls. The decrease in MCAv in anterior circulation stroke with occlusive disease significantly differed from without occlusive disease. However, the sample size was small, and more research is warranted to confirm these findings.

Variations in Cortical Oxygenation by Near-Infrared Spectroscopy According to Head Position after Acute Stroke: The Preliminary Findings of an Observational Study

Background: After ischemic stroke, there is no general consensus on the optimal position for the head of patients in the acute phase. This observational study aimed to measure the variations in cortical oxygenation using noninvasive functional near-infrared spectroscopy (fNIRS) at different degrees of head positioning on a bed. Methods: Consecutive ischemic stroke patients aged 18 years or older with anterior circulation ischemic stroke within 48 h of symptom onset who could safely assume different positions on a bed were included. A 48-channel fNIRS system was placed in the bilateral sensorimotor cortex. Then, the bed of each patient was moved into four consecutive positions: (1) seated (90° angle between the head and bed surface); (2) lying at 30°; (3) seated again (90°); and (4) lying flat (0°). Each position was maintained for 90 s; the test was conducted 48 h after stroke onset and after 5 ± 1 days. The variations in oxygenated hemoglobin in the global brain surface and for each hemisphere were recorded and compared. Results: Twenty-one patients were included (males, n = 11; age, 79 ± 9 years; ASPECTS, 8 ± 2). When evaluating the affected side, the median oxygenation was significantly greater in the lying-flat (0°) and 30° positions than in the 90° position (p < 0.001 for both comparisons). No significant differences between the supine position and the 30° position were found, although oxygenation was slightly lower in the 30° position than in the supine position (p = 0.063). No differences were observed when comparing recanalized and nonrecanalized patients separately or according to stroke severity. The evaluation conducted 5 days after the stroke confirmed the previous data, with a significant difference in oxygenation at 0° and 30° compared to 90°. Conclusions: This preliminary study suggested that there are no substantial differences in brain oxygenation between the lying-flat head position and the 30° laying position.

Lower admission stroke severity is associated with good collateral status in distal medium vessel occlusion stroke

BACKGROUND AND PURPOSE

Distal medium vessel occlusions (DMVOs) are a significant contributor to acute ischemic stroke (AIS), with collateral status (CS) playing a pivotal role in modulating ischemic damage progression. We aimed to explore baseline characteristics associated with CS in AIS-DMVO.

METHODS

This retrospective analysis of a prospectively collected database enrolled 130 AIS-DMVO patients from two comprehensive stroke centers. Baseline characteristics, including patient demographics, admission National Institutes of Health Stroke Scale (NIHSS) score, admission Los Angeles Motor Scale (LAMS) score, and co-morbidities, including hypertension, hyperlipidemia, diabetes, coronary artery disease, atrial fibrillation, and history of transient ischemic attack or stroke, were collected. The analysis was dichotomized to good CS, reflected by hypoperfusion index ratio (HIR) <.3, versus poor CS, reflected by HIR ≥.3.

RESULTS

Good CS was observed in 34% of the patients. As to the occluded location, 43.8% occurred in proximal M2, 16.9% in mid M2, 35.4% in more distal middle cerebral artery, and 3.8% in distal anterior cerebral artery. In multivariate logistic analysis, a lower NIHSS score and a lower LAMS score were both independently associated with a good CS (odds ratio [OR]: 0.88, 95% confidence interval [CI]: 0.82-0.95, p < .001 and OR: 0.77, 95% CI: 0.62-0.96, p = .018, respectively). Patients with poor CS were more likely to manifest as moderate to severe stroke (29.1% vs. 4.5%, p < .001), while patients with good CS had a significantly higher chance of having a minor stroke clinically (40.9% vs. 12.8%, p < .001).

CONCLUSIONS

CS remains an important determinant in the severity of AIS-DMVO. Collateral enhancement strategies may be a worthwhile pursuit in AIS-DMVO patients with more severe initial stroke presentation, which can be swiftly identified by the concise LAMS and serves as a proxy for underlying poor CS.

The Effects of Head Elevation on Intracranial Pressure, Cerebral Perfusion Pressure, and Cerebral Oxygenation Among Patients with Acute Brain Injury: A Systematic Review and Meta-Analysis

BACKGROUND

Head elevation is recommended as a tier zero measure to decrease high intracranial pressure (ICP) in neurocritical patients. However, its quantitative effects on cerebral perfusion pressure (CPP), jugular bulb oxygen saturation (SjvO2), brain tissue partial pressure of oxygen (PbtO2), and arteriovenous difference of oxygen (AVDO2) are uncertain. Our objective was to evaluate the effects of head elevation on ICP, CPP, SjvO2, PbtO2, and AVDO2 among patients with acute brain injury.

METHODS

We conducted a systematic review and meta-analysis on PubMed, Scopus, and Cochrane Library of studies comparing the effects of different degrees of head elevation on ICP, CPP, SjvO2, PbtO2, and AVDO2.

RESULTS

A total of 25 articles were included in the systematic review. Of these, 16 provided quantitative data regarding outcomes of interest and underwent meta-analyses. The mean ICP of patients with acute brain injury was lower in group with 30° of head elevation than in the supine position group (mean difference [MD] - 5.58 mm Hg; 95% confidence interval [CI] - 6.74 to - 4.41 mm Hg; p < 0.00001). The only comparison in which a greater degree of head elevation did not significantly reduce the ICP was 45° vs. 30°. The mean CPP remained similar between 30° of head elevation and supine position (MD - 2.48 mm Hg; 95% CI - 5.69 to 0.73 mm Hg; p = 0.13). Similar findings were observed in all other comparisons. The mean SjvO2 was similar between the 30° of head elevation and supine position groups (MD 0.32%; 95% CI - 1.67% to 2.32%; p = 0.75), as was the mean PbtO2 (MD - 1.50 mm Hg; 95% CI - 4.62 to 1.62 mm Hg; p = 0.36), and the mean AVDO2 (MD 0.06 µmol/L; 95% CI - 0.20 to 0.32 µmol/L; p = 0.65).The mean ICP of patients with traumatic brain injury was also lower with 30° of head elevation when compared to the supine position. There was no difference in the mean values of mean arterial pressure, CPP, SjvO2, and PbtO2 between these groups.

CONCLUSIONS

Increasing degrees of head elevation were associated, in general, with a lower ICP, whereas CPP and brain oxygenation parameters remained unchanged. The severe traumatic brain injury subanalysis found similar results.

Promising Cerebral Blood Flow Enhancers in Acute Ischemic Stroke

Ischemic stroke presents a major global economic and public health burden. Although recent advances in available endovascular therapies show improved functional outcome, a good number of stroke patients are either ineligible or do not have access to these treatments. Also, robust collateral flow during acute ischemic stroke independently predicts the success of endovascular therapies and the outcome of stroke. Hence, adjunctive therapies for cerebral blood flow (CBF) enhancement are urgently needed. A very clear overview of the pial collaterals and the role of genetics are presented in this review. We review available evidence and advancement for potential therapies aimed at improving CBF during acute ischemic stroke. We identified heme-free soluble guanylate cyclase activators; Sanguinate, remote ischemic perconditioning; Fasudil, S1P agonists; and stimulation of the sphenopalatine ganglion as promising potential CBF-enhancing therapeutics requiring further investigation. Additionally, we outline and discuss the critical steps required to advance research strategies for clinically translatable CBF-enhancing agents in the context of acute ischemic stroke models.

A systematic review on the assessment of cerebral autoregulation in patients with Large Vessel Occlusion

As the majority of large vessel occlusion (LVO) patients are not treated with revascularization therapies or efficiently revascularized, complementary management strategies are needed. In this article we explore the importance of cerebral autoregulation (CA) assessment in the prediction and/or modification of infarct growth and hemorrhagic transformation. In patients with LVO, these are important factors that affect prognosis. A systematic search of the PubMed, EMBASE databases and a targeted Google search was conducted, resulting in the inclusion of 34 relevant articles. There is an agreement that CA is impaired in patients with LVO; several factors have been identified such as time course, revascularization status, laterality, disease subtype and location, some of which may be potentially modifiable and affect outcomes. The personalized CA assessment of these patients suggests potential for better understanding of the inter-individual variability. Further research is needed for the development of more accurate, noninvasive techniques for continuous monitoring and personalized thresholds for CA.

Timing of Initiation of Acute Stroke Rehabilitation and Management Corresponding to Complications at Primary Stroke Centers in Japan: A Nationwide Cross-Sectional Web-Based Questionnaire Survey

INTRODUCTION

Many guidelines now recommend early rehabilitation for acute stroke patients. However, evidence remains lacking regarding the specific timings for initiation of various rehabilitation steps and management when complications are encountered in acute stroke rehabilitation. This survey aimed to investigate actual clinical situations in acute stroke rehabilitation in Japan and to improve the medical systems for rehabilitation and plan further studies.

METHODS

This nationwide, cross-sectional, web-based questionnaire survey was administered between February 7, 2022, and April 21, 2022, targeting all primary stroke centers (PSCs) in Japan. Among several components of the survey, this paper focused on the timing of the initiation of three rehabilitation steps (passive bed exercise; head elevation; and out-of-bed mobilization), along with the management of rehabilitation (continued or suspended) in the event of complications during acute stroke rehabilitation. We also investigated the influence of facility features on these contents.

RESULTS

Responses were obtained from 639 of the 959 PSCs surveyed (response rate: 66.6%). In cases of ischemic stroke and intracerebral hemorrhage, most PSCs initiated passive bed exercise on day 1, head elevation on day 1, and out-of-bed mobilization on day 2 (with day of admission defined as day 1). In cases with subarachnoid hemorrhage, rehabilitation steps were delayed compared to other stroke subtypes or showed wide variation depending on the facility. Passive bed exercise was accelerated by the presence of protocols for rehabilitation and weekend rehabilitation. Out-of-bed mobilization was accelerated by the presence of a stroke care unit. Facilities with board-certified rehabilitation doctors were cautious regarding the initiation of head elevation. Most PSCs suspended rehabilitation training in the event of symptomatic systemic/neurological complications.

CONCLUSION

Our survey revealed the actual situation of acute stroke rehabilitation in Japan and indicated that some facility features appear to influence early increases in physical activity levels and early mobilization. Our survey provides fundamental data to improve the medical systems for acute stroke rehabilitation in the future.

A randomized trial of Trendelenburg position for acute moderate ischemic stroke

We aim to explore the effect of head-down position (HDP), initiated within 24 hours of onset, in moderate anterior circulation stroke patients with probable large artery atherosclerosis (LAA) etiology. This investigator-initiated, multi-center trial prospective, randomized, open-label, blinded-endpoint, multi-center and phase-2 trial was conducted in China and completed in 2021. Eligible patients were randomly assigned (1:1) into the HDP group receiving -20° Trendelenburg, or control group receiving standard care according to national guideline. The primary endpoint was proportion of modified Rankin Scale (mRS) of 0 to 2 at 90 days, which is a scale for measuring the degree of disability after stroke. 90-day mRS was assessed by a certified staff member who was blinded to group assignment. A total of 96 patients were randomized (47 in HDP group and 49 in control group) and 94 (97.9%) patients were included in the final analysis: 46 in HDP group and 48 in control group. The proportion of favorable outcome was 65.2% (30/46) in the HDP group versus 50.0% (24/48) in the control group (unadjusted: OR 2.05 [95%CI 0.87-4.82], P = 0.099). No severe adverse event was attributed to HDP procedures. This work suggests that the head-down position seems safe and feasible, but does not improve favorable functional outcome in acute moderate stroke patients with LAA. This trial was registered with ClinicalTrials.gov, NCT03744533.

Early mobilisation is associated with lower subacute blood pressure and variability in ICH: A retrospective cohort study✰

BACKGROUND

Very early rehabilitation after stroke appears to worsen outcome, particularly in intracerebral haemorrhage (ICH). Plausible mechanisms include increased mean blood pressure (BP) and BP variability.

AIMS

To test associations between early mobilisation, subacute BP and survival, in observational data of ICH patients during routine clinical care.

METHODS

We collected demographic, clinical and imaging data from 1372 consecutive spontaneous ICH patients admitted between 2 June 2013 and 28 September 2018. Time to first mobilisation (defined as walking, standing, or sitting out-of-bed) was extracted from electronic records. We evaluated associations between early mobilisation (within 24 h of onset) and both subacute BP and death by 30 days using multifactorial linear and logistic regression analyses respectively.

RESULTS

Mobilisation at 24 h was not associated with increased odds of death by 30 days when adjusting for key prognostic factors (OR 0.4, 95% CI 0.2 to 1.1, p = 0.07). Mobilisation at 24 h was independently associated with both lower mean systolic BP (-4.5 mmHg, 95% CI -7.5 to -1.5 mmHg, p = 0.003) and lower diastolic BP variability (-1.3 mmHg, 95% CI -2.4 to -0.2 mg, p = 0.02) during the first 72 h after admission.

CONCLUSIONS

Adjusted analysis in this observational dataset did not find an association between early mobilisation and death by 30 days. We found early mobilisation at 24 h to be independently associated with lower mean systolic BP and lower diastolic BP variability over 72 h. Further work is needed to establish mechanisms for the possible detrimental effect of early mobilisation in ICH.

Early mobilization in acute stroke phase: a systematic review

BACKGROUND

Early mobilization is defined as out-of-bed activities in acute stroke phase, and has led to improvements in functional capacity and reduction of complications after stroke.

OBJECTIVE

This study aimed to investigate the effectiveness and safety of early mobilization in the acute stroke phase.

METHODS

This was a systematic review. We searched for studies with the keywords: "Stroke," "Early mobilization" and "Functional outcomes." Data source: NLM, LILACS, MEDLINE, PEDro, and Science Direct. Studies published up to June 2020 were included; (b) study eligibility criteria: clinical trials; (c) participants: stroke patients in the acute phase; (d) interventions: early mobilization; (e) study appraisal: two authors independently assessed the risk of bias, Grading of Recommendations Assessment, Development and Evaluation, and the Oxford Center for Evidence-Based Medicine Levels of Evidence. The safety was evaluated based on related and non-related adverse effects.

RESULTS

Altogether, 476 studies were retrieved. After exclusion, seven studies involving 8663 patients were included in the qualitative synthesis. The main activities were elevation of the headboard, sitting, standing, and walking. The most important outcome assessed was the modified Rankin scale score (disability) after 3 months of stroke, and two studies showed that early mobilization improves functional capacity after stroke.

CONCLUSION

the optimal time to start early mobilization is > 24 h of stroke according to hemodynamic stability and safety criteria. The duration of mobilization is recommended between 15 and 45 minutes, divided into one, two, or three times a day. The focus of early mobilization should be on sitting, standing, and walking activity.

International beliefs and head positioning practices in patients with spontaneous hyperacute intracerebral hemorrhage

Background

Prior to the conduct of the Head Position in Stroke Trial (HeadPoST), an international survey (n = 128) revealed equipoise for selection of head position in acute ischemic stroke.

Objectives

We aimed to determine whether equipoise exists for head position in spontaneous hyperacute intracerebral hemorrhage (ICH) patients following HeadPoST.

Design

This is an international, web-distributed survey focused on head positioning in hyperacute ICH patients.

Methods

A survey was constructed to examine clinicians' beliefs and practices associated with head positioning of hyperacute ICH patients. Survey items were developed with content experts, piloted, and then refined before distributing through stroke listservs, social media, and purposive snowball sampling. Data were analyzed using descriptive statistics and χ² test.

Results

We received 181 responses representing 13 countries on four continents: 38% advanced practice providers, 32% bedside nurses, and 30% physicians; overall, participants had median 7 [interquartile range (IQR) = 3-12] years stroke experience with a median of 100 (IQR = 37.5-200) ICH admissions managed annually. Participants disagreed that HeadPoST provided 'definitive evidence' for head position in ICH and agreed that their 'written admission orders include 30-degree head positioning', with 54% citing hospital policies for this head position in hyperacute ICH. Participants were unsure whether head positioning alone could influence ICH longitudinal outcomes. Use of serial proximal clinical and technology measures during the head positioning intervention were identified by 82% as the most appropriate endpoints for future ICH head positioning trials.

Conclusion

Interdisciplinary providers remain unconvinced by HeadPoST results that head position does not matter in hyperacute ICH. Future trials examining the proximal effects of head positioning on clinical stability in hyperacute ICH are warranted.

Effect of head-down tilt on clinical outcome and cerebral perfusion in ischemic stroke patients: A case series

Background

The effect of head position on stroke is not clear. The current study aimed to observe the effect of head-down tilt on acute ischemic stroke (AIS) patients with large vessel occlusion.

Methods

We observed the influence of head-down tilt position on clinical outcomes, myocardial enzymogram and N-terminal pro b-type Natriuretic Peptide in 4 AIS patients who suffered early neurological deterioration (END). Cerebral perfusion imaging was performed in 3 patients using arterial spin labeling.

Results

In series of AIS patients with END, head down tilt (-20°) prevented further neurological deterioration and improved clinical outcomes. An increase in cerebral blood flow was observed by arterial spin labeling after head down tilt treatment. No obvious adverse events occurred.

Conclusion

The case series suggest that head-down tilt may improve clinical outcome in AIS patients through increasing the cerebral perfusion with no obvious adverse events. The finding needs to be confirmed in future clinical trials.

Evaluation of the effect of endotracheal aspiration at different head heights on oxygenation of the brain by non-invasive method in intensive care patients

OBJECTIVES

To determine the effect of endotracheal aspiration at different head heights on oxygenation brain by non-invasive method in neurosurgery intensive care patients.

BACKGROUND

Head elevation of mechanical ventilator-dependent neurosurgery patients and the possible risks of endotracheal aspiration are closely related to the clinical conditions of the patients.

DESIGN

A prospective quasi-experimental study with repetitive measurements in a single group.

METHODS

In the study, neurosurgery intensive care patients were adjusted to a head height of 15, 30 and 45° (n = 46, power analysis %90). Cerebral oxygenation levels were determined with a non-invasive device at each head height before and in the 1st, 5th and 30th min of endotracheal aspiration. Data were collected with Patient Information Form and cerebral oxygenation device based on NIRS technology. This study performed according to the TREND reporting guidelines for non-randomized/quasi experimental study.

RESULTS

The highest cerebral oxygenation value was obtained at 30 min. The decrease in the cerebral oxygenation levels of the patients was highest in the 1st min after endotracheal aspiration, at a head height of 15 degrees for the right cerebral region and at a head height of 30 degrees for the left cerebral region. The increase in oxygenation of the right and left cerebral regions occurred highest at a head height of 45 degrees.

CONCLUSIONS

The ideal head height should be 45 degrees during and after endotracheal aspiration in regard to maintaining cerebral oxygenation in neurosurgery intensive care patients. It is extremely important to monitor the cerebral oxygenation status of patients, with non-invasive measurement tools during and after endotracheal aspiration, to prevent secondary complications.

RELEVANCE TO CLINICAL PRACTICE

This study reveals the importance of raising the head 45 degrees in the best preservation of cerebral oxygenation values in neurosurgery intensive care patients. Intensive care nurses should pay attention to maintaining this head height.

Pre-stroke Physical Activity and Cerebral Collateral Circulation in Ischemic Stroke: A Potential Therapeutic Relationship?

Favorable cerebral collateral circulation contributes to hindering penumbral tissue from progressing to infarction and is associated with positive clinical outcomes after stroke. Given its clinical importance, improving cerebral collateral circulation is considered a therapeutic target to reduce burden after stroke. We provide a hypothesis-generating discussion on the potential association between pre-stroke physical activity and cerebral collateral circulation in ischemic stroke. The recruitment of cerebral collaterals in acute ischemic stroke may depend on anatomical variations, capacity of collateral vessels to vasodilate, and individual risk factors. Physical activity is associated with improved cerebral endothelial and vascular function related to vasodilation and angiogenic adaptations, and risk reduction in individual risk factors. More research is needed to understand association between cerebral collateral circulation and physical activity. A presentation of different methodological considerations for measuring cerebral collateral circulation and pre-stroke physical activity in the context of acute ischemic stroke is included. Opportunities for future research into cerebral collateral circulation, physical activity, and stroke recovery is presented.

Effect of a temporary lying position on cerebral hemodynamic and cerebral oxygenation parameters in patients with severe brain trauma

BACKGROUND

Temporary transition from the half-seated position (HSP) to the lying position (LyP) is often associated with an increase in intracranial pressure (ICP) during management of patients with severe traumatic brain injury (TBI). This study was designed to assess the impact of the temporary LyP on cerebral perfusion and oxygenation in cases of severe TBI.

METHOD

Patients with a severe blunt TBI with indication of ICP monitoring were prospectively included. Patients underwent standardized management according to the international guidelines to minimize secondary insults. For each patient, a maneuver to a LyP for 30 min was performed daily during the first 7 days of hospitalization. ICP, cerebral perfusion pressure (CPP), mean velocity (V_m), pulsatility index (PI), regional cerebral oxygen saturation (rScO₂), jugular venous oxygen saturation (SvjO₂)) were compared in the HSP and the LyP.

RESULTS

Twenty-four 24 patients were included. The median Glasgow coma scale score was 6 (interquartile range (IQR), 3-8), the median injury severity score was 32 (IQR, 25-48), and the mean age was 39 ± 16 years. On day 1, ICP (+ 6 mmHg (IQR, 4-7 mmHg)) and CPP (+ 10 mmHg (IQR, 5-14 mmHg) were significantly increased in the LyP compared with the HSP. V_m increased significantly in the LyP on the mainly injured side (+ 6 cm/s (IQR, + 0-11 cm/s); P = 0.01) and on the less injured side (+ 4 cm/s (IQR, + 1-8 cm/s); P < 0.01). rScO₂ behaved similarly (+ 2 points (IQR, + 2-4 points) and + 3 points (IQR, + 2-5 points), respectively; P < 0.001). Mixed models highlighted the significant association between the position and CPP, V_m, rScO₂, with more favorable conditions in the lying position.

CONCLUSIONS

Within the first week of management, the temporary LyP in cases of severe TBI was associated with a moderate increase in CPP, V_m, and rScO₂despite a moderate increase in ICP.

Time Window for Ischemic Stroke First Mobilization Effectiveness: Protocol for an Investigator-Initiated Prospective Multicenter Randomized 3-Arm Clinical Trial

OBJECTIVE

The purpose of this study is to investigate the optimal time window for initiating mobilizing after acute ischemic stroke.

METHODS

The TIME Trial is a pragmatic, investigator-initiated, multi-center, randomized, 3-arm parallel group, clinical trial. This trial will be conducted in 57 general hospitals in mainland China affiliated with the China Stroke Databank Center and will enroll 6033 eligible patients with acute ischemic stroke. Participants will be randomly allocated to either (1) the very early mobilization group in which mobilization is initiated within 24 hours from stroke onset, (2) the early mobilization group in which mobilization begins between 24 and 72 hours poststroke, or (3) the late mobilization group in which mobilization is started after 72 hours poststroke. The mobilization protocol is otherwise standardized and identical for each comparison group. Mobilization is titrated by baseline mobility level and progress of patients throughout the intervention period. The primary outcome is death or disability assessed with the modified Rankin scale at 3 months poststroke. Secondary outcomes include impairment score of the National Institutes of Health Stroke Scale, dependence in activities of daily living as measured using the modified Barthel Index, cognitive ability assessed with the Mini-Mental State Examination, incidence of adverse events, hospital length of stay, and total medical costs.

IMPACT

The TIME Trial is designed to answer the question "when is the best time to start mobilization after stroke?" The effect of timing is isolated from the effect of type and dose of mobilization by otherwise applying a standard mobilization protocol across groups. The TIME Trial may, therefore, contribute to increasing the knowledge base regarding the optimal time window for initiating mobilization after acute ischemic stroke.

Rehabilitating the neurological patient in the ICU: what is important?

PURPOSE OF REVIEW

To describe recent literature evaluating the effectiveness of early rehabilitation in neurocritical care patients.

RECENT FINDINGS

There is a drive for early rehabilitation within the ICU; however, there are unique considerations for the neurocritically ill patient that include hemiplegia, cognitive impairments and impaired conscious state that can complicate rehabilitation. Additionally, neurological complications, such as hemorrhage expansion and cerebral edema can lead to the risk of further neurological damage. It is, therefore, important to consider the effect of exercise and position changes on cerebral hemodynamics in patients with impaired cerebral autoregulation. There is a paucity of evidence to provide recommendations on timing of early rehabilitation postneurological insult. There are also mixed findings on the effectiveness of early mobilization with one large, multicenter RCT demonstrating the potential harm of early and intensive mobilization in stroke patients. Conversely, observational trials have found early rehabilitation to be well tolerated and feasible, reduce hospital length of stay and improve functional outcomes in neurological patients admitted to ICU.

SUMMARY

Further research is warranted to determine the benefits and harm of early rehabilitation in neurological patients. As current evidence is limited, and given recent findings in stroke studies, careful consideration should be taken when prescribing exercises in neurocritically ill patients.

Head positioning in suspected patients with acute stroke from prehospital to emergency department settings: a systematic review and meta-analysis

Aim

This study aimed to clarify whether the lying‐flat position from prehospital to emergency department settings more effectively improves neurological outcomes of patients suspected with acute stroke over the sitting‐up position.

Methods

We searched PubMed, the Cochrane Central Register of Controlled Trials, and Igaku Chuo Zasshi for published randomized controlled trials until September 2019. The study population included patients suspected with acute stroke from prehospital to emergency department settings. We compared outcomes between the lying‐flat position and sitting‐up position groups. The critical outcome was the modified Rankin Scale score at 90 days, and important composite outcomes were 90‐day mortality, pneumonia recurrence, and recurrent ischemic stroke. The certainty of evidence of the outcome level was compared using the Grading of Recommendations Assessment, Development, and Evaluation approach.

Results

In total, 881 studies were identified from the databases, and two randomized controlled trials were included in the analysis. The pooled risk ratio of 90‐day modified Rankin Scale score was not statistically significant (risk ratio 0.86; 95% confidence interval [CI] 0.56–1.32) between the lying‐flat position and sitting‐up position groups. When comparing the 90‐day mortality, pneumonia occurrence, and recurrent ischemic stroke, no significant differences were observed between the two groups. Risk ratio was 1.00 (95% CI 0.87–1.14), 0.90 (95% CI 0.74–1.11), and 0.81 (95% CI 0.14–4.64) for 90‐day mortality, pneumonia occurrence, and recurrent ischemic stroke, respectively.

Conclusion

This study suggests that the lying‐flat position is not more effective than the sitting‐up position in terms of 90‐day modified Rankin Scale score in patients suspected with acute stroke.

Head down tilt 15° in experimental intracerebral hemorrhage: a randomized noninferiority safety trial

BACKGROUND AND PURPOSE

Head down tilt 15° (HDT15°), applied before recanalization, increases collateral flow and improves outcome in experimental ischemic stroke. For its simplicity and low cost, HDT15° holds considerable potential to be developed as an emergency treatment of acute stroke in the prehospital setting, where hemorrhagic stroke is the major mimic of ischemic stroke. In this study, we assessed safety of HDT15° in the acute phase of experimental intracerebral hemorrhage.

METHODS

Intracerebral hemorrhage was produced by stereotaxic injection of collagenase in Wistar rats. A randomized noninferiority trial design was used to assign rats to HDT15° or flat position (n = 64). HDT15° was applied for 1 h during the time window of hematoma expansion. The primary outcome was hematoma volume at 24 h. Secondary outcomes were mass effect, mortality, and functional deficit in the main study and acute changes of intracranial pressure, hematoma growth, and cardiorespiratory parameters in separate sets of randomized animals (n = 32).

RESULTS

HDT15° achieved the specified criteria of noninferiority for hematoma volume at 24 h. Mass effect, mortality, and functional deficit at 24 h showed no difference in the two groups. HDT15° induced a mild increase in intracranial pressure with respect to the pretreatment values (+2.91 ± 1.76 mmHg). HDT15° had a neutral effect on MRI-based analysis of hematoma growth and cardiorespiratory parameters.

CONCLUSIONS

Application of HDT15° in the hyperacute phase of experimental intracerebral hemorrhage does not worsen early outcome. Further research is needed to implement HDT15° as an emergency collateral therapeutic for acute stroke.

The effect of head positioning on cerebral hemodynamics: Experiences in mild ischemic stroke

BACKGROUND AND PURPOSE

It is generally agreed that optimal head positioning is an important consideration in acute stroke management regime. However, there is limited literature investigating the effect of head positioning changes on cerebrovascular physiology in acute ischemic stroke (AIS). We aim to assess cerebral autoregulation (CA) and associated hemodynamic responses during gradual head positioning (GHP) changes, between AIS and controls.

METHODS

Cerebral blood flow velocity (CBFV, transcranial Doppler), blood pressure (BP, Finometer) and end-tidal CO₂ (capnography) were recorded between lying flat (0°) and sitting up (30°) head position, in 16 controls (8 women, mean age 57 ± 16 yrs) and 15 AIS patients (7 women, 69 ± 8 yrs). AIS patients carried out three visits at 13.3 ± 6.9 h, 4.8 ± 3.2 days and 93.9 ± 11.5 days from symptom onset, respectively.

RESULTS

AIS patients were significantly hypertensive (p = 0.005), hypocapnic (p < 0.001), and had lower CBFV (p = 0.02) compared to controls, in both head positions. When comparing 5-min FLAT to SIT head position, reductions in BP (both AIS and controls, p < 0.001) and CBFV (controls only: dominant hemisphere p = 0.001 and non-dominant hemisphere p = 0.05) were demonstrated. Of note, a reduction in autoregulation index was observed in AIS, after 5-min SIT head positioning, at all 3 visits (p = 0.018).

CONCLUSION

Key hemodynamic changes were demonstrated when the head position changes from 5-min FLAT to SIT head position (GHP) in mildly affected stroke patients. Importantly, these were associated with non-significant changes in CBFV but reduced measures of CA following AIS, which may be relevant in determining the optimal head position and the ideal timing of mobilisation. Clinical Trial Registration - URL: http://www.clinicaltrials.gov. Unique Identifier: NCT02932540.

Early head-up mobilisation versus standard care for patients with severe acquired brain injury: A systematic review with meta-analysis and Trial Sequential Analysis

BACKGROUND

There is increasing focus on earlier rehabilitation in patients with traumatic or hypoxic brain injury or stroke. This systematic review evaluates the benefits and harms of early head-up mobilisation versus standard care in patients with severe acquired brain injury.

METHODS

We searched Medline, CENTRAL, EMBASE, four other databases and 13 selected clinical trial registries until April 2020. Eligible randomised clinical trials compared early head-up mobilisation versus standard care in patients with severe acquired brain injury and were analysed conducting random- and fixed-effects meta-analyses and Trial Sequential Analysis (TSA). Certainty of evidence was assessed by GRADE.

MAIN RESULTS

We identified four randomised clinical trials (total n = 385 patients) with severe acquired brain injury (stroke 86% and traumatic brain injury 13%). Two trials were at low risk and two at high risk of bias. We found no evidence of a difference between early mobilisation vs. standard care on mortality or poor functional outcome at end of the intervention (relative risk (RR) 1.19, 95% CI 0.93 to 1.53; I2 0%; very low certainty) or at maximal follow-up (RR 1.03, 95% CI 0.89 to 1.21; I2 0%; very low certainty). We found evidence against an effect on quality of life at maximal follow-up. The proportion of patients with at least one serious adverse event did not differ at end of intervention or at maximal follow-up. For most comparisons, TSA suggested that further trials are needed.

CONCLUSIONS

We found no evidence of a difference between early mobilisation versus standard care for patients with severe acquired brain injury. Early mobilisation appeared not to exert a major impact on quality of life. This systematic review highlights the insufficient evidence in patients with severe brain injury, and no firm conclusions can be drawn from these data.

TRIAL REGISTRATION

Protocol uploaded to PROSPERO: April 2018 (revised October 2018, CRD42018088790).

Cerebrovascular Complications of Pediatric Blunt Trauma

Ischemic and hemorrhagic stroke can occur in the setting of pediatric trauma, particularly those with head or neck injuries. The risk of stroke appears highest within the first two weeks after trauma. Stroke diagnosis may be challenging due to lack of awareness or concurrent injuries limiting detailed neurological assessment. Other injuries may also complicate stroke management, with competing priorities for blood pressure, ventilator management, or antithrombotic timing. Here we review epidemiology, clinical presentation, and diagnostic approach to blunt arterial injuries including dissection, cerebral sinovenous thrombosis, mineralizing angiopathy, stroke from abusive head trauma, and traumatic hemorrhagic stroke. Owing to the complexities and heterogeneity of concomitant injuries in stroke related to trauma, a single pathway for stroke management is impractical. Therefore providers must understand the goals and possible costs or consequences of stroke management decisions to individualize patient care. We discuss the physiological principles of cerebral perfusion and oxygen delivery, considerations for ventilator strategy when stroke and lung injury are present, and current available evidence of the risks and benefits of anticoagulation to provide a framework for multidisciplinary discussions of cerebrovascular injury management in pediatric patients with trauma.

12 versus 24 h bed rest after acute ischemic stroke thrombolysis: a preliminary experience

BACKGROUND

The practice of ≥24 h of bed rest after acute ischemic stroke thrombolysis is common among hospitals, but its value compared to shorter periods of bed rest is unknown.

METHODS

Consecutive adult patients with a diagnosis of ischemic stroke who had received intravenous thrombolysis treatment from 1/1/2010 until 4/13/2016, identified from the local ischemic stroke registry, were included. Standard practice bed rest for ≥24 h, the protocol prior to 1/27/2014, was retrospectively compared with standard practice bed rest for ≥12 h, the protocol after that date. The primary outcome was favorable discharge location (defined as home, home with services, or acute rehabilitation). Secondary outcome measures included incidence of pneumonia, NIHSS at discharge, and length of stay.

RESULTS

392 patients were identified (203 in the ≥24 h group, 189 in the ≥12 h group). There was no significant difference in favorable discharge outcome in the ≥24 h bed rest protocol compared with the ≥12 h bed rest protocol in multivariable logistic regression analysis (76.2% vs. 70.9%, adjusted OR 1.20 CI 0.71-2.03). Compared with the ≥24 h bed rest group, pneumonia rates (8.3% versus 1.6%, adjusted OR 0.12 CI 0.03-0.55), median discharge NIHSS (3 versus 2, adjusted p = .034), and mean length of stay (5.4 versus 3.5 days, adjusted p = .006) were lower in the ≥12 h bed rest group.

CONCLUSION

Compared with ≥24 h bed rest, ≥12 h bed rest after acute ischemic stroke reperfusion therapy appeared to be similar. A non-inferiority randomized trial is needed to verify these findings.

Management of acute ischemic stroke

Stroke is the leading cause of long term disability in developed countries and one of the top causes of mortality worldwide. The past decade has seen substantial advances in the diagnostic and treatment options available to minimize the impact of acute ischemic stroke. The key first step in stroke care is early identification of patients with stroke and triage to centers capable of delivering the appropriate treatment, as fast as possible. Here, we review the data supporting pre-hospital and emergency stroke care, including use of emergency medical services protocols for identification of patients with stroke, intravenous thrombolysis in acute ischemic stroke including updates to recommended patient eligibility criteria and treatment time windows, and advanced imaging techniques with automated interpretation to identify patients with large areas of brain at risk but without large completed infarcts who are likely to benefit from endovascular thrombectomy in extended time windows from symptom onset. We also review protocols for management of patient physiologic parameters to minimize infarct volumes and recent updates in secondary prevention recommendations including short term use of dual antiplatelet therapy to prevent recurrent stroke in the high risk period immediately after stroke. Finally, we discuss emerging therapies and questions for future research.

Aerobic Training and Mobilization Early Post-stroke: Cautions and Considerations

Knowledge gaps exist in how we implement aerobic exercise programs during the early phases post-stroke. Therefore, the objective of this review was to provide evidence-based guidelines for pre-participation screening, mobilization, and aerobic exercise training in the hyper-acute and acute phases post-stroke. In reviewing the literature to determine safe timelines of when to initiate exercise and mobilization we considered the following factors: arterial blood pressure dysregulation, cardiac complications, blood-brain barrier disruption, hemorrhagic stroke transformation, and ischemic penumbra viability. These stroke-related impairments could intensify with inappropriate mobilization/aerobic exercise, hence we deemed the integrity of cerebral autoregulation to be an essential physiological consideration to protect the brain when progressing exercise intensity. Pre-participation screening criteria are proposed and countermeasures to protect the brain from potentially adverse circulatory effects before, during, and following mobilization/exercise sessions are introduced. For example, prolonged periods of standing and static postures before and after mobilization/aerobic exercise may elicit blood pooling and/or trigger coagulation cascades and/or cerebral hypoperfusion. Countermeasures such as avoiding prolonged standing or incorporating periodic lower limb movement to activate the venous muscle pump could counteract blood pooling after an exercise session, minimize activation of the coagulation cascade, and mitigate potential cerebral hypoperfusion. We discuss patient safety in light of the complex nature of stroke presentations (i.e., type, severity, and etiology), medical history, comorbidities such as diabetes, cardiac manifestations, medications, and complications such as anemia and dehydration. The guidelines are easily incorporated into the care model, are low-risk, and use minimal resources. These and other strategies represent opportunities for improving the safety of the activity regimen offered to those in the early phases post-stroke. The timeline for initiating and progressing exercise/mobilization parameters are contingent on recovery stages both from neurobiological and cardiovascular perspectives, which to this point have not been specifically considered in practice. This review includes tailored exercise and mobilization prescription strategies and precautions that are not resource intensive and prioritize safety in stroke recovery.

Transient Laterality of Cerebral Oxygenation Changes in Response to Head-of-Bed Manipulation in Acute Ischemic Stroke

Background: Cerebral oxygenation monitoring provides important information for optimizing individualized management in patients with acute ischemic stroke (AIS). Although changes in cerebral oxygenation are known to occur in response to head-of-bed (HOB) elevation within 72 h after onset, changes in cerebral oxygenation during stroke recovery are unclear. We compared changes in total- (tHb), oxygenated- (HbO2), and deoxygenated-hemoglobin (deoxyHb) concentrations in response to HOB manipulation between the timeframes within 72 h and 7–10 days after AIS onset. Methods: We measured forehead ΔtHb, ΔHbO2, and ΔdeoxyHb in response to HOB elevation (30°) within 72 h (first measurement) and 7–10 days (second measurement) after AIS onset using time-resolved near-infrared spectroscopy. Results: We enrolled 30 participants (mean age 72.8 ± 11.3 years; 13 women) with a first AIS. There were no significant differences in ΔtHb, ΔHbO2, or ΔdeoxyHb measurements on the infarct or contra-infarct side. At the first measurement, ΔtHb, ΔHbO2, and ΔdeoxyHb measured on the contra-infarct side did not correlate with those measured on the infarct side: ΔtHb (r = 0.114, p = 0.539); ΔHbO2 (r = 0.143, p = 0.440); ΔdeoxyHb (r = 0.227, p = 0.221). Notably, at the second measurement, correlation coefficients of ΔtHb and ΔHbO2 between the contra-infarct and infarct sides were statistically significant: ΔtHb (r = 0.491, p = 0.008); ΔHbO2 (r = 0.479, p = 0.010); ΔdeoxyHb (r = 0.358, p = 0.054). Conclusion: Although changes in cerebral oxygenation in response to HOB elevation had a laterality difference between hemispheres within 72 h of AIS onset, the difference had decreased, at least partially, 7–10 days after AIS onset.

Early Mobilization After Stroke Is Not Associated With Cognitive Outcome

Background and Purpose- We aimed to determine whether early mobilization after stroke affects subsequent cognitive function. Methods- AVERT (A Very Early Rehabilitation Trial) was an international, 56-site, phase 3 randomized controlled trial, conducted from 2006 to 2015. Participants were included if they were aged 18+, presented within 24 hours of stroke, and satisfied physiological limits for blood pressure, heart rate, and temperature. Participants were randomized to receive either usual stroke unit care or very early and more frequent mobilization in addition to usual stroke unit care. The Montreal Cognitive Assessment, scored 0 to 30, was introduced as a 3-month outcome during 2008. Results- Of the 2104 patients included in AVERT, 317 were assessed before the Montreal Cognitive Assessment's introduction. Of the remaining 1787, 1189 (66.5%) had complete Montreal Cognitive Assessment data, 456 (25.5%) had partially or completely missing data, 136 (7.6%) had died, and 6 (0.3%) were lost to follow-up. In surviving participants with complete data, adjusting for age and stroke severity, total Montreal Cognitive Assessment score was no different in the intervention (n=595; median, 23; interquartile range, 19-26; mean, 21.9; SD, 5.9) and usual care (n=594; median, 23; interquartile range, 19-26; mean, 21.8; SD, 5.9) groups ( P=0.68). Conclusions- Exposure to earlier and more frequent mobilization in the acute stage of stroke does not influence cognitive outcome at 3 months. This stands in contrast to the primary outcome from AVERT (modified Rankin Scale), where the intervention group had less favorable outcomes than controls. Clinical Trial Registration- URL: https://www.anzctr.org.au . Unique identifier: ACTRN12606000185561.

Cerebral Hemodynamic Evaluation After Cerebral Recanalization Therapy for Acute Ischemic Stroke

Cerebral recanalization therapy, either intravenous thrombolysis or mechanical thrombectomy, improves the outcomes in patients with acute ischemic stroke (AIS) by restoring the cerebral perfusion of the ischemic penumbra. Cerebral hemodynamic evaluation after recanalization therapy, can help identify patients with high risks of reperfusion-associated complications. Among the various hemodynamic modalities, magnetic resonance imaging (MRI), computed tomography perfusion, and transcranial Doppler sonography (TCD) are the most commonly used. Poststroke hypoperfusion is associated with infarct expansion, while hyperperfusion, which once was considered the hallmark of successful recanalization, is associated with hemorrhagic transformation. Either the hypo- or the hyperperfusion may result in poor clinical outcomes. Individual blood pressure target based on cerebral hemodynamic evaluation was crucial to improve the prognosis. This review summarizes literature on cerebral hemodynamic evaluation and management after recanalization therapy to guide clinical decision making.

High Intensity Physical Rehabilitation Later Than 24 h Post Stroke Is Beneficial in Patients: A Pilot Randomized Controlled Trial (RCT) Study in Mild to Moderate Ischemic Stroke

Objective: Very early mobilization was thought to contribute to beneficial outcomes in stroke-unit care, but the optimal intervention strategy including initiation time and intensity of mobilization are unclear. In this study, we sought to confirm the rehabilitative effects of different initiation times (24 vs. 48 h) with different mobilization intensities (routine or intensive) in ischemic stroke patients within three groups. Materials and Methods: We conducted a randomized and controlled trial with a blinded follow-up assessment. Patients with ischemic stroke, first or recurrent, admitted to stroke unit within 24 h after stroke onset were recruited. Eligible subjects were randomly assigned (1:1:1) to 3 groups: Early Routine Mobilization in which patients received < 1.5 h/d out-of-bed mobilization within 24-48 h after stroke onset, Early Intensive Mobilization in which patients initiated ≥3 h/d mobilization at 24-48 h after the stroke onset, and Very Early Intensive Mobilization in which patients received≥3 h/d mobilization within 24 h. The modified Rankin Scale score of 0-2 was used as the primary favorable outcome. Results: We analyzed 248 of the 300 patients (80 in Early Routine Mobilization, 82 in Very Early Intensive Mobilization and 86 in Early Intensive Mobilization), with 52 dropping out (20 in Early Routine Mobilization, 18 in Very Early Intensive Mobilization and 14 in Early Intensive Mobilization). Among the three groups, the Early Intensive Mobilization group had the most favorable outcomes at 3-month follow-up, followed by patients in the Early Routine Mobilization group. Patients in Very Early Intensive Mobilization received the least odds of favorable outcomes. At 3 month follow up, 53.5%, (n = 46) of patients with Early Intensive Mobilization showed a favorable outcome (modified Rankin Scale 0-2) (p = 0.041) as compared to 37.8% (n = 31) of patients in the Very Early Intensive Mobilization. Conclusions: Post-stroke rehabilitation with high intensity physical exercise at 48 h may be beneficial. Very Early Intensive Mobilization did not lead to a favorable outcome at 3 months. Clinical Trial Registration: www.chictr.org.cn, identifier ChiCTR-ICR-15005992.

Early microvascular cerebral blood flow response to head-of-bed elevation is related to outcome in acute ischemic stroke

BACKGROUND AND AIMS

Previously, microvascular cerebral blood flow (CBF) response to a mild head-of-bed (HOB) elevation has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS). We have hypothesized that early CBF response is related to the functional outcome.

METHODS

Patients with a non-lacunar AIS in the anterior circulation were monitored by DCS to measure relative CBF (ΔrCBF) on the frontal lobes bilaterally during a 0°-30° HOB elevation at early (≤ 12) or late (> 12) hours from symptom onset. National Institutes of Health Stroke Scale (NIHSS) scores were recorded at baseline at 24 and at 48 h. Functional outcome was measured by the modified Rankin Scale (mRS) at 3 months.

RESULTS

Thirty-eight (n = 38) AIS patients [baseline NIHSS = 19 (interquartile range: 16, 21)] were studied. ΔrCBF decreased similarly in both hemispheres (p = 0.4) when HOB was elevated and was not associated with baseline and follow-up NIHSS scores or patient demographics. At the early phase (n = 17), a lower or paradoxical ΔrCBF response to HOB elevation was associated with an unfavorable functional outcome (mRS > 2) in the ipsilesional (but not in the contralesional) hemisphere (p = 0.010). ΔrCBF response in the late acute phase was not related to mRS.

CONCLUSIONS

Early CBF response to mild HOB elevation in the ipsilesional hemisphere is related to functional outcome. Further studies may enable optical monitoring at the bedside to individualize management strategies in the early phase of AIS.

[Effects of body positioning in patients with non-traumatic intracranial hemorrhages]

The article presents an analysis of different methods of positioning patients with acute cerebral pathology. Changing of 'head-of-the bed' position is a routine and simple method of correction of intracranial hypertension. For the majority of patients with cerebral damage, regardless of the etiological factor, 15-30° 'head - of - the bed' position is preferable. However, in some cases head-of-bed manipulation can lead to the irreversible ischemic damage due to the reduction in systemic and perfusion pressure and cerebral blood flow. Thus, the selection of the optimal body position in different types of acute cerebral pathology remains a debated issue.

Lower body negative pressure to safely reduce intracranial pressure

KEY POINTS

During long-term missions, some astronauts experience structural and functional changes of the eyes and brain which resemble signs/symptoms experienced by patients with intracranial hypertension. Weightlessness prevents the normal cerebral volume and pressure 'unloading' associated with upright postures on Earth, which may be part of the cerebral and ocular pathophysiology. By placing the lower body in a negative pressure device (LBNP) that pulls fluid away from cranial compartments, we simulated effects of gravity and significantly lowered pressure within the brain parenchyma and ventricle compartments. Application of incremental LBNP demonstrated a non-linear dose-response curve, suggesting 20 mmHg LBNP as the optimal level for reducing pressure in the brain without impairing cerebral perfusion pressure. This non-invasive method of reducing pressure in the brain holds potential as a countermeasure in space as well as having treatment potential for patients on Earth with traumatic brain injury or other pathology leading to intracranial hypertension.

ABSTRACT

Patients with elevated intracranial pressure (ICP) exhibit neuro-ocular symptoms including headache, papilloedema and loss of vision. Some of these symptoms are also present in astronauts during and after prolonged space-flight where lack of gravitational stress prevents daily lowering of ICP associated with upright posture. Lower body negative pressure (LBNP) simulates the effects of gravity by displacing fluid caudally and we hypothesized that LBNP would lower ICP without compromising cerebral perfusion. Ten cerebrally intact volunteers were included: six ambulatory neurosurgical patients with parenchymal ICP-sensors and four former cancer patients with Ommaya-reservoirs to the frontal horn of a lateral ventricle. We applied LBNP while recording ICP and blood pressure while supine, and during simulated intracranial hypertension by 15° head-down tilt. LBNP from 0 to 50 mmHg at increments of 10 mmHg lowered ICP in a non-linear dose-dependent fashion; when supine (n = 10), ICP was decreased from 15 ± 2 mmHg to 14 ± 4, 12 ± 5, 11 ± 4, 10 ± 3 and 9 ± 4 mmHg, respectively (P < 0.0001). Cerebral perfusion pressure (CPP), calculated as mean arterial blood pressure at midbrain level minus ICP, was unchanged (from 70 ± 12 mmHg to 67 ± 9, 69 ± 10, 70 ± 12, 72 ± 13 and 74 ± 15 mmHg; P = 0.02). A 15° head-down tilt (n = 6) increased ICP to 26 ± 4 mmHg, while application of LBNP lowered ICP (to 21 ± 4, 20 ± 4, 18 ± 4, 17 ± 4 and 17 ± 4 mmHg; P < 0.0001) and increased CPP (P < 0.01). An LBNP of 20 mmHg may be the optimal level to lower ICP without impairing CPP to counteract spaceflight-associated neuro-ocular syndrome in astronauts. Furthermore, LBNP holds clinical potential as a safe, non-invasive method for lowering ICP and improving CPP for patients with pathologically elevated ICP on Earth.

Very early versus delayed mobilisation after stroke

BACKGROUND

Very early mobilisation (VEM) is performed in some stroke units and recommended in some acute stroke clinical guidelines. However, it is unclear whether very early mobilisation independently improves outcome after stroke.

OBJECTIVES

To determine whether very early mobilisation (started as soon as possible, and no later than 48 hours after onset of symptoms) in people with acute stroke improves recovery (primarily the proportion of independent survivors) compared with usual care.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched 31 July 2017). We also systematically searched 19 electronic databases including; CENTRAL; 2017, Issue 7 in the Cochrane Library (searched July 2017), MEDLINE Ovid (1950 to August 2017), Embase Ovid (1980 to August 2017), CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to August 2017) , PsycINFO Ovid (1806 to August 2017), AMED Ovid (Allied and Complementary Medicine Database), SPORTDiscus EBSCO (1830 to August 2017). We searched relevant ongoing trials and research registers (searched December 2016), the Chinese medical database, Wanfangdata (searched to November 2016), and reference lists, and contacted researchers in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of people with acute stroke, comparing an intervention group that started out-of-bed mobilisation within 48 hours of stroke, and aimed to reduce time-to-first mobilisation, with or without an increase in the amount or frequency (or both) of mobilisation activities, with usual care, where time-to-first mobilisation was commenced later.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, extracted data, assessed risk of bias, and applied the GRADE approach to assess the quality of the evidence. The primary outcome was death or poor outcome (dependency or institutionalisation) at the end of scheduled follow-up. Secondary outcomes included death, dependency, institutionalisation, activities of daily living (ADL), extended ADL, quality of life, walking ability, complications (e.g. deep vein thrombosis), patient mood, and length of hospital stay. We also analysed outcomes at three-month follow-up.

MAIN RESULTS

We included nine RCTs with 2958 participants; one trial provided most of the information (2104 participants). The median (range) delay to starting mobilisation after stroke onset was 18.5 (13.1 to 43) hours in the VEM group and 33.3 (22.5 to 71.5) hours in the usual care group. The median difference within trials was 12.7 (4 to 45.6) hours. Other differences in intervention varied between trials; in five trials, the VEM group were also reported to have received more time in therapy, or more mobilisation activity.Primary outcome data were available for 2542 of 2618 (97.1%) participants randomized and followed up for a median of three months. VEM probably led to similar or slightly more deaths and participants who had a poor outcome, compared with delayed mobilisation (51% versus 49%; odds ratio (OR) 1.08, 95% confidence interval (CI) 0.92 to 1.26; P = 0.36; 8 trials; moderate-quality evidence). Death occurred in 7% of participants who received delayed mobilisation, and 8.5% of participants who received VEM (OR 1.27, 95% CI 0.95 to 1.70; P = 0.11; 8 trials, 2570 participants; moderate-quality evidence), and the effects on experiencing any complication were unclear (OR 0.88; 95% CI 0.73 to 1.06; P = 0.18; 7 trials, 2778 participants; low-quality evidence). Analysis using outcomes collected only at three-month follow-up did not alter the conclusions.The mean ADL score (measured at end of follow-up, with the 20-point Barthel Index) was higher in those who received VEM compared with the usual care group (mean difference (MD) 1.94, 95% CI 0.75 to 3.13, P = 0.001; 8 trials, 9 comparisons, 2630/2904 participants (90.6%); low-quality evidence), but there was substantial heterogeneity (93%). Effect sizes were smaller for outcomes collected at three-month follow-up, rather than later.The mean length of stay was shorter in those who received VEM compared with the usual care group (MD -1.44, 95% CI -2.28 to -0.60, P = 0.0008; 8 trials, 2532/2618 participants (96.7%); low-quality evidence). Confidence in the answer was limited by the variable definitions of length of stay. The other secondary outcome analyses (institutionalisation, extended activities of daily living, quality of life, walking ability, patient mood) were limited by lack of data.Sensitivity analyses by trial quality: none of the outcome conclusions were altered if we restricted analyses to trials with the lowest risk of bias (based on method of randomization, allocation concealment, completeness of follow-up, and blinding of final assessment), or information about the amount of mobilisation.Sensitivity analysis by intervention characteristics: analyses restricted to trials where the mean VEM time-to-first mobilisation was less than 24 hours, showed an odds of death of 1.35 (95% CI 0.99 to 1.83; P = 0.06; I² = 25%; 5 trials). Analyses restricted to the trials that clearly reported a more prolonged out-of-bed activity showed a similar primary outcome (OR 1.14; 0.96 to 1.35; P = 0.13; I² = 28%; 5 trials), and odds of death (OR 1.27; 0.93 to 1.73; P = 0.13; I² = 0%; 4 trials) to the main analysis.Exploratory network meta-analysis (NMA): we were unable to analyze by the amount of therapy, but low-quality evidence indicated that time-to-first mobilisation at around 24 hours was associated with the lowest odds of death or poor outcome, compared with earlier or later mobilisation.

AUTHORS' CONCLUSIONS

VEM, which usually involved first mobilisation within 24 hours of stroke onset, did not increase the number of people who survived or made a good recovery after their stroke. VEM may have reduced the length of stay in hospital by about one day, but this was based on low-quality evidence. Based on the potential hazards reported in the single largest RCT, the sensitivity analysis of trials commencing mobilisation within 24 hours, and the NMA, there was concern that VEM commencing within 24 hours may carry an increased risk, at least in some people with stroke. Given the uncertainty around these effect estimates, more detailed research is still required.

The practice and predictors of early mobilization of patients post-acute admission to a specialized stroke center

BACKGROUND

Early mobilization (EM) post-stroke is recommended; however, the ideal timing and nature of EM, and factors that may influence EM practice are unclear.

OBJECTIVES

The primary objective was to describe the type and extent of mobilization 0-48 h post-stroke admission to acute hospital care. A secondary objective was to evaluate whether pre-stroke functional level, stroke severity, tissue plasminogen activator (tPA) administration, and level of consciousness (LOC) predicted any passive, any active, and out-of-bed mobilization (i.e. sitting at edge-of-bed, standing, or ambulation) 0-24 h post-admission.

METHODS

A quantitative, cross-sectional, retrospective review of health records of patients admitted to a specialized acute stroke center in 2016 was conducted.

RESULTS

Data from 296 eligible health records were abstracted. Median age was 73 years, and 87% of patients had sustained an ischemic stroke. Active, passive, and out-of-bed mobilization occurred in 91.6%, 57.1%, and 24.3% of patients by 12 h post-admission, respectively, and 99.3%, 78.4%, and 77.4% of patients by 48 h post-admission, respectively. Administration of tPA, stroke severity, and impaired LOC, were each associated with any passive mobilization, and no tPA administration, stroke severity, and normal LOC were each associated with out-of-bed mobilization 0-24 h post-admission (p < 0.05).

CONCLUSIONS

Almost all patients receive active mobilization by 12 h post-admission whereas out-of-bed mobilization is infrequent. In the first 24 h post-admission, clinicians may prioritize passive over out-of-bed mobilization when patients have received tPA, present with severe stroke, and have impaired LOC. This conservative approach is unsurprising given the lack of clear practice recommendations for these situations.

Acute Treatment of Stroke (Except Thrombectomy)

PURPOSE OF REVIEW

The management of patients with acute stroke has been revolutionized in recent years with the advent of new effective treatments. In this rapidly evolving field, we provide an update on the management of acute stroke excluding thrombectomy, looking to recent, ongoing, and future trials.

RECENT FINDINGS

Large definitive trials have provided insight into acute stroke care including broadening the therapeutic window for thrombolysis, alternatives to standard dose alteplase, the use of dual antiplatelet therapy early after minor ischemic stroke, and treating elevated blood pressure in intracerebral hemorrhage. Further ongoing and future trials are eagerly awaited in this ever-expanding area. Although definitive trials have led to improvements in acute stroke care, there remains a need for further research to improve our understanding of pathophysiological mechanisms underlying different stroke types with the potential for treatments to be tailored to the individual.

A Very Early Rehabilitation Trial after stroke (AVERT): a Phase III, multicentre, randomised controlled trial

BACKGROUND

Mobilising patients early after stroke [early mobilisation (EM)] is thought to contribute to the beneficial effects of stroke unit care but it is poorly defined and lacks direct evidence of benefit.

OBJECTIVES

We assessed the effectiveness of frequent higher dose very early mobilisation (VEM) after stroke.

DESIGN

We conducted a parallel-group, single-blind, prospective randomised controlled trial with blinded end-point assessment using a web-based computer-generated stratified randomisation.

SETTING

The trial took place in 56 acute stroke units in five countries.

PARTICIPANTS

We included adult patients with a first or recurrent stroke who met physiological inclusion criteria.

INTERVENTIONS

Patients received either usual stroke unit care (UC) or UC plus VEM commencing within 24 hours of stroke.

MAIN OUTCOME MEASURES

The primary outcome was good recovery [modified Rankin scale (mRS) score of 0-2] 3 months after stroke. Secondary outcomes at 3 months were the mRS, time to achieve walking 50 m, serious adverse events, quality of life (QoL) and costs at 12 months. Tertiary outcomes included a dose-response analysis.

DATA SOURCES

Patients, outcome assessors and investigators involved in the trial were blinded to treatment allocation.

RESULTS

We recruited 2104 (UK, n = 610; Australasia, n = 1494) patients: 1054 allocated to VEM and 1050 to UC. Intervention protocol targets were achieved. Compared with UC, VEM patients mobilised 4.8 hours [95% confidence interval (CI) 4.1 to 5.7 hours; p < 0.0001] earlier, with an additional three (95% CI 3.0 to 3.5; p < 0.0001) mobilisation sessions per day. Fewer patients in the VEM group (n = 480, 46%) had a favourable outcome than in the UC group (n = 525, 50%) (adjusted odds ratio 0.73, 95% CI 0.59 to 0.90; p = 0.004). Results were consistent between Australasian and UK settings. There were no statistically significant differences in secondary outcomes at 3 months and QoL at 12 months. Dose-response analysis found a consistent pattern of an improved odds of efficacy and safety outcomes in association with increased daily frequency of out-of-bed sessions but a reduced odds with an increased amount of mobilisation (minutes per day).

LIMITATIONS

UC clinicians started mobilisation earlier each year altering the context of the trial. Other potential confounding factors included staff patient interaction.

CONCLUSIONS

Patients in the VEM group were mobilised earlier and with a higher dose of therapy than those in the UC group, which was already early. This VEM protocol was associated with reduced odds of favourable outcome at 3 months cautioning against very early high-dose mobilisation. At 12 months, health-related QoL was similar regardless of group. Shorter, more frequent mobilisation early after stroke may be associated with a more favourable outcome.

FUTURE WORK

These results informed a new trial proposal [A Very Early Rehabilitation Trial - DOSE (AVERT-DOSE)] aiming to determine the optimal frequency and dose of EM.

TRIAL REGISTRATION

The trial is registered with the Australian New Zealand Clinical Trials Registry number ACTRN12606000185561, Current Controlled Trials ISRCTN98129255 and ISRCTN98129255.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 54. See the NIHR Journals Library website for further project information. Funding was also received from the National Health and Medical Research Council Australia, Singapore Health, Chest Heart and Stroke Scotland, Northern Ireland Chest Heart and Stroke, and the Stroke Association. In addition, National Health and Medical Research Council fellowship funding was provided to Julie Bernhardt (1058635), who also received fellowship funding from the Australia Research Council (0991086) and the National Heart Foundation (G04M1571). The Florey Institute of Neuroscience and Mental Health, which hosted the trial, acknowledges the support received from the Victorian Government via the Operational Infrastructure Support Scheme.

Guidelines for evaluation and management of cerebral collateral circulation in ischaemic stroke 2017

Collateral circulation plays a vital role in sustaining blood flow to the ischaemic areas in acute, subacute or chronic phases after an ischaemic stroke or transient ischaemic attack. Good collateral circulation has shown protective effects towards a favourable functional outcome and a lower risk of recurrence in stroke attributed to different aetiologies or undergoing medical or endovascular treatment. Over the past decade, the importance of collateral circulation has attracted more attention and is becoming a hot spot for research. However, the diversity in imaging methods and criteria to evaluate collateral circulation has hindered comparisons of findings from different cohorts and further studies in exploring the clinical relevance of collateral circulation and possible methods to enhance collateral flow. The statement is aimed to update currently available evidence and provide evidence-based recommendations regarding grading methods for collateral circulation, its significance in patients with stroke and methods under investigation to improve collateral flow.

Physiological Effects of Early Incremental Mobilization of a Patient with Acute Intracerebral and Intraventricular Hemorrhage Requiring Dual External Ventricular Drainage

BACKGROUND

Recent trials have challenged the notion that very early mobility benefits patients with acute stroke. It is unclear how cerebral autoregulatory impairments, prevalent in this population, could be affected by mobilization. The safety of mobilizing patients who have external ventricular drainage (EVD) devices for cerebrospinal fluid diversion and intracranial pressure (ICP) monitoring is another concern due to risk of device dislodgment and potential elevation in ICP. We report hemodynamic and ICP responses during progressive, device-assisted mobility interventions performed in a critically ill patient with intracerebral hemorrhage (ICH) requiring two EVDs.

METHODS

A 55-year-old man was admitted to the Neuroscience Critical Care Unit with an acute thalamic ICH and complex intraventricular hemorrhage requiring placement of two EVDs. Progressive mobilization was achieved using mobility technology devices. Range of motion exercises were performed initially, progressing to supine cycle ergometry followed by incremental verticalization using a tilt table. Physiological parameters were recorded before and after the interventions.

RESULTS

All mobility interventions were completed without any adverse event or clinically detectable change in the patient's neurological state. Physiological parameters including hemodynamic variables and ICP remained within prescribed goals throughout.

CONCLUSION

Progressive, device-assisted early mobilization was feasible and safe in this critically ill patient with hemorrhagic stroke when titrated by an interdisciplinary team of skilled healthcare professionals. Studies are needed to gain insight into the hemodynamic and neurophysiological responses associated with early mobility in acute stroke to identify subsets of patients who are most likely to benefit from this intervention.

Refocusing Neuroprotection in Cerebral Reperfusion Era: New Challenges and Strategies

Pathophysiological processes of stroke have revealed that the damaged brain should be considered as an integral structure to be protected. However, promising neuroprotective drugs have failed when translated to clinical trials. In this review, we evaluated previous studies of neuroprotection and found that unsound patient selection and evaluation methods, single-target treatments, etc., without cerebral revascularization may be major reasons of failed neuroprotective strategies. Fortunately, this may be reversed by recent advances that provide increased revascularization with increased availability of endovascular procedures. However, the current improved effects of endovascular therapy are not able to match to the higher rate of revascularization, which may be ascribed to cerebral ischemia/reperfusion injury and lacking of neuroprotection. Accordingly, we suggest various research strategies to improve the lower therapeutic efficacy for ischemic stroke treatment: (1) multitarget neuroprotectant combinative therapy (cocktail therapy) should be investigated and performed based on revascularization; (2) and more efforts should be dedicated to shifting research emphasis to establish recirculation, increasing functional collateral circulation and elucidating brain–blood barrier damage mechanisms to reduce hemorrhagic transformation. Therefore, we propose that a comprehensive neuroprotective strategy before and after the endovascular treatment may speed progress toward improving neuroprotection after stroke to protect against brain injury.

HeadPoST

Objective

To critique the Head Positioning in Stroke Trial (HeadPoST) study methods in relation to preceding research findings in an aim to clarify the potential efficacy of positioning interventions and direction for future research.

Methods

Head positioning research prior to the conduct of HeadPoST was reviewed by a team of international stroke experts, and methods and findings were compared to HeadPoST.

Results

Methods used to select HeadPoST patients differ substantially from those used in original head positioning studies, in particular enrollment of all types of stroke. HeadPoST enrolled primarily minor strokes (median NIH Stroke Scale 4, interquartile range [IQR] 2–8) without vascular imaging confirmation of subtype; elapsed time from stroke symptom onset to the initiation of intervention was late (median 14 hours, IQR 5–35), and time from hospital admission to enrollment was delayed (median 7 hours, IQR 2–26). Intervention integrity was not reported, including ability to achieve/maintain 30° head elevation in beds lacking head elevation capabilities. Deterioration or improvement associated with the intervention is unknown as serial assessments were not completed, and the trial's 3-month outcome was powered using unrelated study data.

Conclusions

The design of HeadPoST was suboptimal to measure differences produced by the intervention. Future head positioning trials in discrete patient cohorts (in particular, large vessel occlusion) with endpoints supported by pilot work are required to understand the efficacy of this simple yet potentially important intervention.

Impact of acute-phase complications and interventions on 6-month survival after stroke. A prospective observational study

The outcome of stroke patients is complex and multidimensional. We evaluated the impact of acute-phase variables, including clinical state, complications, resource use and interventions, on 6-month survival after first-ever stroke, taking into account baseline conditions exerting a possible effect on outcome.

As part of a National Research Program, we performed a prospective observational study of acute stroke patients in four Italian Regions. Consecutive patients admitted for a period of 3 months to the emergency rooms of participating hospitals were included.

A total of 1030 patients were enrolled (median age 76.0 years, 52.1% males). At 6 months, 816 (79.2%) were alive, and 164 (15.9%) deceased. Survival status at the 6-month follow-up was missing for 50 (4.9%). Neurological state in the acute phase was significantly worse in patients deceased at 6 months, who showed also higher frequency of acute-phase complications. Cox regression analysis adjusted for demographics, pre-stroke function, baseline diseases and risk factors, indicated as significant predictors of 6-month death altered consciousness (HR, 1.70; 95% CI, 1.14–2.53), total anterior circulation infarct (HR, 2.13; 95% CI, 1.44–3.15), hyperthermia (HR, 1.70; 95% CI, 1.18–2.45), pneumonia (HR, 1.76; 95% CI, 1.18–2.61), heart failure (HR, 2.87; 95% CI, 1.34–6.13) and nasogastric feeding (HR, 2.35; 95% CI, 1.53–3.60), while antiplatelet therapy during acute phase (HR, 0.56; 95% CI, 0.39–0.79), and early mobilisation (HR, 0.55; 95% CI, 0.36–0.84) significantly increased 6-month survival.

In a prospective observational study, stroke severity and some acute-phase complications, potentially modifiable, significantly increased the risk of 6-month death, independently of baseline variables. Early mobilisation positively affected survival, highlighting the role of early rehabilitation after stroke.