COmbination of Targeted temperature management and Thrombectomy after acute Ischemic Stroke (COTTIS): a pilot study

BACKGROUND

To evaluate the feasibility and safety of a fast initiation of cooling to a target temperature of 35°C by means of transnasal cooling in patients with anterior circulation large vessel occlusion (LVO) undergoing endovascular thrombectomy (EVT).

METHODS

Patients with an LVO onset of <24 hour who had an indication for EVT were included in the study. Transnasal cooling (RhinoChill) was initiated immediately after the patient was intubated for EVT and continued until an oesophageal target temperature of 35°C was reached. Hypothermia was maintained with surface cooling for 6-hour postrecanalisation, followed by active rewarming (+0.2°C/hour). The primary outcome was defined as the time required to reach 35°C, while secondary outcomes comprised clinical, radiological and safety parameters.

RESULTS

Twenty-two patients (median age, 77 years) were included in the study (14 received additional thrombolysis, 4 additional stenting of the proximal internal carotid artery). The median time intervals were 309 min for last-seen-normal-to-groin, 58 min for door-to-cooling-initiation, 65 min for door-to-groin and 123 min for door-to-recanalisation. The target temperature of 35°C was reached within 30 min (range 13-78 min), corresponding to a cooling rate of 2.6 °C/hour. On recanalisation, 86% of the patients had a body temperature of ≤35°C. The median National Institutes of Health Stroke Scale at admission was 15 and improved to 2 by day 7, and 68% of patients had a good outcome (modified Rankin Scale 0-2) at 3 months. Postprocedure complications included asymptomatic bradycardia (32%), pneumonia (18%) and asymptomatic haemorrhagic transformation (18%).

CONCLUSION

The combined application of hypothermia and thrombectomy was found to be feasible in sedated and ventilated patents. Adverse events were comparable to those previously described for EVT in the absence of hypothermia. The effect of this procedure will next be evaluated in the randomised COmbination of Targeted temperature management and Thrombectomy after acute Ischemic Stroke-2 trial.

Milestones in the history of neurocritical care

Over the last century, significant milestones have been achieved in managing critical illness and diagnosing and treating neurological diseases. Building upon these milestones, the field of neurocritical care emerged in the 1980 and 1990 s at the convergence of critical care medicine and acute neurological treatment. This comprehensive review presents a historical account of key developments in neurocritical care in both the United States and Europe, with a special emphasis on German contributions. The scope of the review encompasses: the foundations of neurocritical care, including post-operative units in the 1920s and 30s, respiratory support during the poliomyelitis epidemics in the 40 and 50 s, cardiac and hemodynamic care in the 60 and 70 s, and stroke units in the 80 and 90 s; key innovations including cerebral angiography, computed tomography, and intracranial pressure and multi-modal monitoring; and advances in stroke, traumatic brain injury, cardiac arrest, neuromuscular disorders, meningitis and encephalitis. These advances have revolutionized the management of neurological emergencies, emphasizing interdisciplinary teamwork, evidence-based protocols, and personalized approaches to care.

Rapid recovery of poststroke cardiac autonomic dysfunction: Causes to be considered

BACKGROUND AND PURPOSE

Acute stroke frequently causes cardiovascular-autonomic dysfunction (CAD). Studies of CAD recovery are inconclusive, whereas poststroke arrhythmias may wane within 72 h. We evaluated whether poststroke CAD recovers within 72 h upon stroke onset in association with neurological improvement or increased use of cardiovascular medication.

METHODS

In 50 ischemic stroke patients (68 ± 13 years old) who-prior to hospital-admission-had no known diseases nor took medication affecting autonomic modulation, we assessed National Institutes of Health Stroke Scale (NIHSS) scores, RR intervals (RRIs), systolic and diastolic blood pressure (BP), respiration rate, parameters reflecting total autonomic modulation (RRI SD, RRI total powers), sympathetic modulation (RRI low-frequency powers, systolic BP low-frequency powers), and parasympathetic modulation (square root of mean squared differences of successive RRIs [RMSSD], RRI high-frequency powers), and baroreflex sensitivity within 24 h (Assessment 1) and 72 h after stroke onset (Assessment 2) and compared data to those of 31 healthy controls (64 ± 10 years). We correlated delta NIHSS values (Assessment 1 - Assessment 2) with delta values of autonomic parameters (Spearman rank correlation tests; significance: p < 0.05).

RESULTS

At Assessment 1, patients were not yet on vasoactive medication and had higher systolic BP, respiration rate, and heart rate, that is, lower RRIs, but lower RRI SD, RRI coefficient of variance, RRI low-frequency powers, RRI high-frequency powers, RRI total powers, RMSSDs, and baroreflex sensitivity. At Assessment 2, patients were on antihypertensives, had higher RRI SD, RRI coefficient of variance, RRI low-frequency powers, RRI high-frequency powers, RRI total powers, RMSSDs, and baroreflex sensitivity but lower systolic blood pressure and NIHSS values than at Assessment 1; values no longer differed between patients and controls except for lower RRIs and higher respiration rate in patients. Delta NIHSS scores correlated inversely with delta values of RRI SD, RRI coefficient of variance, RMSSDs, RRI low-frequency powers, RRI high-frequency powers, RRI total powers, and baroreflex sensitivity.

CONCLUSIONS

In our patients, CAD recovery was almost complete within 72 h after stroke onset and correlated with neurological improvement. Most likely, early initiation of cardiovascular medication and probably attenuating stress supported rapid CAD recovery.

Consensus recommendations on therapeutic hypothermia after minimally invasive intracerebral hemorrhage evacuation from the hypothermia for intracerebral hemorrhage (HICH) working group

Background and purpose

Therapeutic hypothermia (TH), or targeted temperature management (TTM), is a classic treatment option for reducing inflammation and potentially other destructive processes across a wide range of pathologies, and has been successfully used in numerous disease states. The ability for TH to improve neurological outcomes seems promising for inflammatory injuries but has yet to demonstrate clinical benefit in the intracerebral hemorrhage (ICH) patient population. Minimally invasive ICH evacuation also presents a promising option for ICH treatment with strong preclinical data but has yet to demonstrate functional improvement in large randomized trials. The biochemical mechanisms of action of ICH evacuation and TH appear to be synergistic, and thus combining hematoma evacuation with cooling therapy could provide synergistic benefits. The purpose of this working group was to develop consensus recommendations on optimal clinical trial design and outcomes for the use of therapeutic hypothermia in ICH in conjunction with minimally invasive ICH evacuation.

Methods

An international panel of experts on the intersection of critical-care TH and ICH was convened to analyze available evidence and form a consensus on critical elements of a focal cooling protocol and clinical trial design. Three focused sessions and three full-group meetings were held virtually from December 2020 to February 2021. Each meeting focused on a specific subtopic, allowing for guided, open discussion.

Results

These recommendations detail key elements of a clinical cooling protocol and an outline for the roll-out of clinical trials to test and validate the use of TH in conjunction with hematoma evacuation as well as late-stage protocols to improve the cooling approach. The combined use of systemic normothermia and localized moderate (33.5°C) hypothermia was identified as the most promising treatment strategy.

Conclusions

These recommendations provide a general outline for the use of TH after minimally invasive ICH evacuation. More research is needed to further refine the use and combination of these promising treatment paradigms for this patient population.

Posterior circulation ischemic stroke not involving the brainstem is associated with cardiovascular autonomic dysfunction

BACKGROUND AND PURPOSE

Ischemic stroke may induce cardiovascular autonomic dysfunction. Yet, most previous studies included patients with anterior circulation ischemic stroke or brainstem stroke. It remains unclear whether posterior circulation ischemic stroke (PCIS) without brainstem involvement also compromises cardiovascular autonomic modulation (CAM). Therefore, we aimed to assess CAM in PCIS patients with and without brainstem involvement.

METHODS

In four subgroups of 61 PCIS-patients (14 occipital lobe, 16 thalamic, 12 cerebellar, and 19 brainstem strokes) and 30 healthy controls, we recorded RR-intervals (RRI), systolic, diastolic blood pressures (BPsys, BPdia), and respiration at supine rest during the first week after stroke-onset. We calculated parameters reflecting total CAM [RRI-standard-deviation (RRI-SD), RRI-total-powers], predominantly sympathetic CAM [RRI-low-frequency-powers (RRI-LF-powers) and BPsys-LF-powers] and parasympathetic CAM [Root-Mean-Square-of-Successive-RRI-Differences (RMSSD), RRI-high-frequency-powers (RRI-HF-powers)], sympathetic-parasympathetic balance (RRI-LF/HF-ratios), and baroreflex-sensitivity (BRS). Values were compared between the four PCIS-groups and controls using one-way ANOVA Kruskal-Wallis-tests, with post-hoc analyses. Significance was assumed for P<0.05.

RESULTS

In each PCIS-subgroup, values of RRI, RRI-SD, RMSSD, RRI-HF-powers, and BRS were significantly lower, while BPsys-LF-powers were higher than in the controls. Only in patients with occipital lobe stroke, RRI-LF/HF-ratios were significantly higher than in controls. Otherwise, autonomic parameters did not differ between the four PCIS-subgroups.

CONCLUSIONS

During the first week after stroke-onset, our PCIS patients with occipital lobe, thalamic, cerebellar, or brainstem strokes all had reduced cardiovagal modulation, compromised baroreflex, and increased peripheral sympathetic modulation. The RRI-LF/HF-ratios suggest that sympathetic predominance is slightly more prominent after occipital lobe stroke. PCIS may trigger cardiovascular autonomic dysfunction even without brainstem involvement.

Das ist neu in der Neurointensiv- und Notfallmedizin: die wichtigsten Studien des Jahres im Rück- und Überblick

Die vorliegende Übersichtsarbeit fasst wichtige klinische Studien der neurologischen Notfall- und Intensivmedizin zwischen 2020 und 2021 zusammen zu den Themen: rekanalisierende Therapie beim ischämischen Schlaganfall, Anwendbarkeit und Auswirkung eines zerebralen Sauerstoffgewebemonitorings bei Subarachnoidalblutung, Wirksamkeit induzierter Hypothermie bei Patienten mit „cardiac arrest“ (CA), Wertigkeit früher kranialer Bildgebung nach CA, Relevanz eines schnellen Managements und medikamentöser Therapie beim Status epilepticus sowie Inzidenz von Critical-illness-Polyneuropathie-Myopathie bei intensivpflichtigen COVID-Patienten.

Correction to: Neck cooling induces blood pressure increase and peripheral vasoconstriction in healthy persons

A Correction to this paper has been published: https://doi.org/10.1007/s10072-021-05355-3

Effects of a 4-Step Standard Operating Procedure for the Treatment of Fever in Patients With Acute Stroke

Background and Purpose: Fever in the acute phase of stroke leads to an unfavorable clinical outcome and increased mortality. However, no specific form of effective fever treatment has been established, so far. We analyzed the effectiveness of our in-house standard operating procedure (SOP) of fever treatment. Methods: This SOP was analyzed for a period of 33 weeks. Patients with cerebral ischemia (ischemic stroke, transient ischemic attack) or cerebral hemorrhage (intracerebral, subarachnoid) and body temperature elevation of ≥ 37.5°C within the first 6 days after admission were eligible for inclusion in the analysis. The results of SOP group, who's data have been collected prospectively were then compared with a historical control group that had been treated conventionally 1 year earlier in the same period. The data of control group have been collected in retrospect. The primary endpoint was the total duration of the fever for the first 6 days after admission to the stroke unit. Results: A total of 130 patients (mean age of 78 ± 12) received 370 antipyretic interventions. Sequential application of paracetamol (n = 245), metamizole (n = 53) and calf compress (n = 15) led to significant reduction in body temperature. In patients who did not respond to these applications, normothermia could be achieved after infusion of the cooled saline solution. Normothermia could be achieved within 120 min in more than 90% of the cases treated by the SOP. The SOP reduced the fever duration in the 6 days significantly, from 12.2 ± 2.7 h [95% confidence interval (CI) for mean] in the control group to 3.9 ± 1.0 h (95% CI) in the SOP group (p < 0.001). The SOP was rated to be reasonable and effective. Conclusion: Our in-house SOP is cost-efficient and effective for fever treatment in stroke patients, that can be implemented by local health care professionals.

Neck cooling induces blood pressure increase and peripheral vasoconstriction in healthy persons

Introduction

Noninvasive temperature modulation by localized neck cooling might be desirable in the prehospital phase of acute hypoxic brain injuries. While combined head and neck cooling induces significant discomfort, peripheral vasoconstriction, and blood pressure increase, localized neck cooling more selectively targets blood vessels that supply the brain, spares thermal receptors of the face and skull, and might therefore cause less discomfort cardiovascular side effects compared to head- and neck cooling. The purpose of this study is to assess the effects of noninvasive selective neck cooling on cardiovascular parameters and cerebral blood flow velocity (CBFV).

Methods

Eleven healthy persons (6 women, mean age 42 ± 11 years) underwent 90 min of localized dorsal and frontal neck cooling (EMCOOLS Brain.Pad™) without sedation. Before and after cooling onset, and after every 10 min of cooling, we determined rectal, tympanic, and neck skin temperatures. Before and after cooling onset, after 60- and 90-min cooling, we monitored RR intervals (RRI), systolic, diastolic blood pressures (BPsys, BPdia), laser Doppler skin blood flow (SBF) at the index finger pulp, and CBFV at the proximal middle cerebral artery (MCA). We compared values before and during cooling by analysis of variance for repeated measurements with post hoc analysis (significance: p < 0.05).

Results

Neck skin temperature dropped significantly by 9.2 ± 4.5 °C (minimum after 40 min), while tympanic temperature decreased by only 0.8 ± 0.4 °C (minimum after 50 min), and rectal temperature by only 0.2 ± 0.3 °C (minimum after 60 min of cooling). Index finger SBF decreased (by 83.4 ± 126.0 PU), BPsys and BPdia increased (by 11.2 ± 13.1 mmHg and 8.0 ± 10.1 mmHg), and heart rate slowed significantly while MCA-CBFV remained unchanged during cooling.

Conclusions

While localized neck cooling prominently lowered neck skin temperature, it had little effect on tympanic temperature but significantly increased BP which may have detrimental effects in patients with acute brain injuries.

Outcomes of Hypothermia in Addition to Decompressive Hemicraniectomy in Treatment of Malignant Middle Cerebral Artery Stroke: A Randomized Clinical Trial

Importance

Moderate hypothermia in addition to early decompressive hemicraniectomy has been suggested to further reduce mortality and improve functional outcome in patients with malignant middle cerebral artery (MCA) stroke.

Objective

To investigate whether moderate hypothermia vs standard treatment after early hemicraniectomy reduces mortality at day 14 in patients with malignant MCA stroke.

Design, Setting, and Participants

This randomized clinical trial recruited patients from August 2011 through September 2015 at 6 German university hospitals with dedicated neurointensive care units. Of the patients treated with hemicraniectomy and assessed for eligibility, patients were randomly assigned to either standard care or moderate hypothermia. Data analysis was completed from December 2016 to June 2018.

Interventions

Moderate hypothermia (temperature, 33.0 ± 1.0°C) was maintained for at least 72 hours immediately after hemicraniectomy.

Main Outcomes and Measures

The primary outcome was mortality rate at day 14 compared with the Fisher exact test and expressed as odds ratio (ORs) with 95% CIs. Rates of patients with serious adverse events were estimated for the period of the first 14 days after hemicraniectomy and 12 months of follow-up. Secondary outcome measures included functional outcome at 12 months.

Results

Of the 50 study participants, 24 were assigned to standard care and 26 to moderate hypothermia. Twenty-eight were male (56%); the mean (SD) patient age was 51.3 (6.6) years. Recruitment was suspended for safety concerns: 12 of 26 patients (46%) in the hypothermia group and 7 of 24 patients (29%) receiving standard care had at least 1 serious adverse event within 14 days (OR, 2.05 [95% CI, 0.56-8.00]; P = .26); after 12 months, rates of serious adverse events were 80% (n = 20 of 25) in the hypothermia group and 43% (n = 10 of 23) in the standard care group (hazard ratio, 2.54 [95% CI, 1.29-5.00]; P = .005). The mortality rate at day 14 was 19% (5 of 26 patients) in the hypothermia group and 13% (3 of 24 patients) in the group receiving standard care (OR, 1.65 [95% CI, 0.28-12.01]; P = .70). There was no significant difference regarding functional outcome after 12 months of follow-up.

Interpretation

In patients with malignant MCA stroke, moderate hypothermia early after hemicraniectomy did not improve mortality and functional outcome compared with standard care, but may cause serious harm in this specific setting.

Trial Registration

http://www.drks.de, identifier DRKS00000623.

Quantitative Signal Intensity in Fluid-Attenuated Inversion Recovery and Treatment Effect in the WAKE-UP Trial

Background and Purpose—

Relative signal intensity of acute ischemic stroke lesions in fluid-attenuated inversion recovery (fluid-attenuated inversion recovery relative signal intensity [FLAIR-rSI]) magnetic resonance imaging is associated with time elapsed since stroke onset with higher intensities signifying longer time intervals. In the randomized controlled WAKE-UP trial (Efficacy and Safety of MRI-Based Thrombolysis in Wake-Up Stroke Trial), intravenous alteplase was effective in patients with unknown onset stroke selected by visual assessment of diffusion weighted imaging fluid-attenuated inversion recovery mismatch, that is, in those with no marked fluid-attenuated inversion recovery hyperintensity in the region of the acute diffusion weighted imaging lesion. In this post hoc analysis, we investigated whether quantitatively measured FLAIR-rSI modifies treatment effect of intravenous alteplase.

Methods—

FLAIR-rSI of stroke lesions was measured relative to signal intensity in a mirrored region in the contralesional hemisphere. The relationship between FLAIR-rSI and treatment effect on functional outcome assessed by the modified Rankin Scale (mRS) after 90 days was analyzed by binary logistic regression using different end points, that is, favorable outcome defined as mRS score of 0 to 1, independent outcome defined as mRS score of 0 to 2, ordinal analysis of mRS scores (shift analysis). All models were adjusted for National Institutes of Health Stroke Scale at symptom onset and stroke lesion volume.

Results—

FLAIR-rSI was successfully quantified in stroke lesions in 433 patients (86% of 503 patients included in WAKE-UP). Mean FLAIR-rSI was 1.06 (SD, 0.09). Interaction of FLAIR-rSI and treatment effect was not significant for mRS score of 0 to 1 ( P =0.169) and shift analysis ( P =0.086) but reached significance for mRS score of 0 to 2 ( P =0.004). We observed a smooth continuing trend of decreasing treatment effects in relation to clinical end points with increasing FLAIR-rSI.

Conclusions—

In patients in whom no marked parenchymal fluid-attenuated inversion recovery hyperintensity was detected by visual judgement in the WAKE-UP trial, higher FLAIR-rSI of diffusion weighted imaging lesions was associated with decreased treatment effects of intravenous thrombolysis. This parallels the known association of treatment effect and elapsing time of stroke onset.

An oxygen-rich atmosphere or systemic fluoxetine extend the time to respiratory arrest in a rat model of obstructive apnea

Audiogenic seizure-prone mice can be protected from seizure-associated death by exposure to an oxygen atmosphere or treatment with selective serotonergic reuptake inhibitors (SSRIs). We have shown previously in a rat model that epileptic seizure activity can spread through brainstem areas to cause sufficient laryngospasm for obstructive apnea and that the period of seizure-associated obstructive apnea can last long enough for respiratory arrest to occur. We hypothesized that both the oxygen-rich atmosphere and SSRIs function by prolonging the time to respiratory arrest, thus ensuring that seizure activity stops before the point of respiratory arrest to allow recovery of respiratory function. To test this hypothesis, we evaluated each preventative treatment in a rat model of controlled airway occlusion where the times to respiratory arrest can be measured. Adult male Sprague Dawley rats (median age = 66 days) were studied in the absence of any seizure activity. By directly studying responses to controlled airway occlusion, rather than airway occlusion secondary to seizure activity, we could isolate the effects of manipulations that might prolong respiratory arrest from the effects of those manipulations on seizure intensity. All group sizes were ≥ 8 animals per group. We found that both oxygen exposure and fluoxetine significantly increased the time to respiratory arrest by up to 65% (p < .0001 for 5 min oxygen exposure; p = .031 for 25 mg/kg fluoxetine tested 60 min after injection) and, given that neither treatment has been shown to significantly alter seizure duration, these increases can account for the protection of either manipulation against death in sudden death models. Importantly, we found that 30 s of exposure to oxygen produced nearly the same protection as 5 min exposure suggesting that oxygen exposure could start after a seizure starts (p = .0012 for 30 s oxygen exposure). Experiments with 50% oxygen/50% air mixtures indicate that the oxygen concentration needs to be above about 60% to ensure that times to respiratory arrest will always be longer than a period of seizure-induced airway occlusion. Selective serotonin reuptake inhibitors, while instructive with regard to mechanism, require impractical dosing and may carry additional risk in the form of greater challenges for resuscitation. We conclude that oxygen exposure or SSRI treatment prevent seizure associated death by sufficiently prolonging the time to respiratory arrest so that respiratory function can recover after the seizure abates and eliminates the stimulus for seizure-induced apnea.

Sphenopalatine Ganglion Stimulation to Augment Cerebral Blood Flow

Background and Purpose—

Many patients with acute ischemic stroke are not eligible for thrombolysis or mechanical reperfusion therapies due to contraindications, inaccessible vascular occlusions, late presentation, or large infarct core. Sphenopalatine ganglion (SPG) stimulation to enhance collateral flow and stabilize the blood-brain barrier offers an alternative, potentially more widely deliverable, therapy.

Methods—

In a randomized, sham-controlled, double-masked trial at 41 centers in 7 countries, patients with anterior circulation ischemic stroke not treated with reperfusion therapies within 24 hours of onset were randomly allocated to active SPG stimulation or sham control. The primary efficacy outcome was improvement beyond expectations on the modified Rankin Scale of global disability at 90 days (sliding dichotomy), assessed in the modified intention-to-treat population. The initial planned sample size was 660 patients, but the trial was stopped early when technical improvements in device placement occurred, so that analysis of accumulated experience could be conducted to inform a successor trial.

Results—

Among 303 enrolled patients, 253 received at least one active SPG or sham stimulation, constituting the modified intention-to-treat population (153 SPG stimulation and 100 sham control). Age was median 73 years (interquartile range, 64–79), 52.6% were female, deficit severity on the National Institutes of Health Stroke Scale was median 11 (interquartile range, 9–15), and time from last known well median 18.6 hours (interquartile range, 14.5–22.5). For the primary outcome, improved 3-month disability beyond expectations, rates in the SPG versus sham treatment groups were 49.7% versus 40.0%; odds ratio, 1.48 (95% CI, 0.89–2.47); P =0.13. A significant treatment interaction with stroke location (cortical versus noncortical) was noted, P =0.04. In the 87 patients with confirmed cortical involvement, rates of improvement beyond expectations were 50.0% versus 27.0%; odds ratio, 2.70 (95% CI, 1.08–6.73); P =0.03. Similar response patterns were observed for all prespecified secondary efficacy outcomes. No differences in mortality or serious adverse event safety end points were observed.

Conclusions—

SPG stimulation within 24 hours of onset is safe in acute ischemic stroke. SPG stimulation was not shown to statistically significantly improve 3-month disability above expectations, though favorable outcomes were nominally higher with SPG stimulation. Beneficial effects may distinctively be conferred in patients with confirmed cortical involvement. The results of this study need to be confirmed in a larger pivotal study.

Clinical Trial Registration—

URL: https://www.clinicaltrials.gov . Unique identifier: NCT03767192.

Identification of adenylate kinase 5 antibodies during routine diagnostics in a tissue-based assay: Three new cases and a review of the literature

Antibodies against adenylate kinase 5 (AK5) have been described in patients with non-paraneoplastic limbic encephalitis, mainly in men around 70 years of age. Routine testing with specific cell-based assays is not yet available. Three patients with episodic anterograde memory problems and depression had extensive limbic lesions and developed severe atrophy, mainly of the medial temporal lobes. The antibodies were identified in serum and CSF based on the typical staining pattern of AK5 antibodies on a tissue-based assay (here, unfixed mouse brain). Subsequently, they were confirmed by a research laboratory through a cell-based assay.

A Single Injection of N-Oleoyldopamine, an Endogenous Agonist for Transient Receptor Potential Vanilloid-1, Induced Brain Hypothermia, but No Neuroprotective Effects in Experimentally Induced Cerebral Ischemia in Rats

Targeted temperature management, or therapeutic hypothermia, is a potent neuroprotective approach after ischemic brain injury. Hypothermia should be induced as soon as possible after the onset of acute stroke to assure better outcomes. Accordingly, drugs with a fast-acting hypothermic effect sustainable through the period of emergency transportation to hospital would have clinical advantages. Activation of the transient receptor potential vanilloid-1 (TRPV1) can induce hypothermia. Our immunohistochemical investigations confirmed that TRPV1 was distributed to perivascular and periventricular regions of the rat brain, where TRPV1 can be easily detected by TRPV1 agonists. An endogenous TRPV1 selective agonist, N-oleoyldopamine (OLDA), and a synthetic antagonist, AMG 9810, were injected intraperitoneally into healthy adult male Wister rats, and brain and core temperatures and gross motor activities were monitored. Comparison with baseline temperatures showed that TRPV1 injection immediately induced mild hypothermia (p < 0.05 in brain and p < 0.01 in body), and AMG 9810 induced immediate mild hyperthermia (not significant). However, the OLDA-induced hypothermia did not decrease lesion volume after middle carotid artery occlusion in rats. Relative to vehicle, OLDA yielded poorer outcomes and AMG 9810 yielded better outcomes in neurological scores and lesion size. Our study showed that, as an agonist of TRPV1, OLDA has suitable hypothermia-inducing properties, but did not decrease lesion volume. Therefore, the search for novel TRPV1 agonists and/or antagonists providing hypothermia and neuroprotection should continue. Further investigations should also target OLDA-induced transient hypothermia combined with long-term hypothermia maintenance with surface cooling, which mimics the anticipated clinical use of this class of drug.

Therapeutic hypothermia for acute ischaemic stroke. Results of a European multicentre, randomised, phase III clinical trial

Introduction

We assessed whether modest systemic cooling started within 6 hours of symptom onset improves functional outcome at three months in awake patients with acute ischaemic stroke.

Patients and methods

In this European randomised open-label clinical trial with blinded outcome assessment, adult patients with acute ischaemic stroke were randomised to cooling to a target body temperature of 34.0–35.0°C, started within 6 h after stroke onset and maintained for 12 or 24 h , versus standard treatment. The primary outcome was the score on the modified Rankin Scale at 91 days, as analysed with ordinal logistic regression.

Results

The trial was stopped after inclusion of 98 of the originally intended 1500 patients because of slow recruitment and cessation of funding. Forty-nine patients were randomised to hypothermia versus 49 to standard treatment. Four patients were lost to follow-up. Of patients randomised to hypothermia, 15 (31%) achieved the predefined cooling targets. The primary outcome did not differ between the groups (odds ratio for good outcome, 1.01; 95% confidence interval, 0.48–2.13; p = 0.97). The number of patients with one or more serious adverse events did not differ between groups (relative risk, 1.22; 95% confidence interval, 0.65–1.94; p = 0.52).

Discussion

In this trial, cooling to a target of 34.0–35.0°C and maintaining this for 12 or 24 h was not feasible in the majority of patients. The final sample was underpowered to detect clinically relevant differences in outcomes.

Conclusion

Before new trials are launched, the feasibility of cooling needs to be improved.

Targeted Temperature Management for Subarachnoid Hemorrhage: Excellent Outcome After Severe Vasospasm-A Case Series

Targeted temperature management (TTM) might improve outcome of patients with severe subarachnoid hemorrhage (SAH) in which vasospasm, delayed cerebral ischemia (DCI), and increased intracranial pressure (ICP) are frequent and severe complications. A series of patients (n = 3) with severe aneurysmatic SAH were treated by TTM if they developed ICP crisis and/or severe vasospasm diagnosed by angiography. Once these complications were detected, body core temperature (BCT) was rapidly decreased to 35°C or 33°C, if necessary. BCT induced and maintained by surface cooling remained at the desired level for at least 72 hours. Rewarming was performed by 1°C, only if the target parameters ICP and velocities in the serial Doppler sonography indicating macrovascular vasospasm improved to regular levels. In case of increase of ICP or middle cerebral arteries velocities BCT was decreased again to the last effective level. The patients developed vasospasm between days 6 and 12 after SAH. All aneurysms were treated by coiling. BCT was reduced between days 6 and 12 after SAH. Total duration of BCT <36.5°C was between 5.5 and 8 days. It remained <35°C for 4-6 days, and at 33°C for 3 days on average. ICP could be sufficiently controlled in all patients, because no ICP crisis was observed during TTM and after rewarming. Two patients developed minor DCI. Side effects of prolonged ventilation of 7-18 days included pneumonia for two patients that could be treated sufficiently. Other complications were one case of ventriculitis and two temporary deliriums. Outcome of the patients was good because no focal neurological symptoms could be detected after rehabilitation. TTM represents a promising treatment approach for severe SAH in which standard treatment is often limited and experimental. It deserves further clinical investigation in a larger cohort.

Palliative Care for Stroke Patients and Their Families: Barriers for Implementation

Stroke is a leading cause of death, disability and is a symptom burden worldwide. It impacts patients and their families in various ways, including physical, emotional, social, and spiritual aspects. As stroke is potentially lethal and causes severe symptom burden, a palliative care (PC) approach is indicated in accordance with the definition of PC published by the WHO in 2002. Stroke patients can benefit from a structured approach to palliative care needs (PCN) and the amelioration of symptom burden. Stroke outcome is uncertain and outlook may change rapidly. Regarding these challenges, core competencies of PC include the critical appraisal of various treatment options, and openly and respectfully discussing therapeutic goals with patients, families, and caregivers. Nevertheless, PC in stroke has to date mainly been restricted to short care periods for dying patients after life-limiting complications. There is currently no integrated concept for PC in stroke care addressing the appropriate moment to initiate PC for stroke patients, and the question of how to screen for symptoms remains unanswered. Therefore, PC for stroke patients is often perceived as a stopgap in cases of unfavorable prognosis and very short survival times. In contrast, PC can provide much more for stroke patients and support a holistic approach, improve quality of life and ensure treatment according to the patient's wishes and values. In this short review we identify key aspects of PC in stroke care and current barriers to implementation. Additionally, we provide insights into our approach to PC in stroke care.

Abstract TMP13: Individual Patient Data Meta-analysis of Hypothermia for Acute Ischaemic Stroke

Background: It remains unclear whether inducing hypothermia is safe and effective for improving outcome after hyperacute ischaemic stroke. An individual patient data meta-analysis of completed trials was performed.

Methods: Following electronic searches for trials comparing hypothermia to control, Chief Investigators were approached to share individual patient data (IPD). Odds ratios (OR, 95% confidence intervals, 95% CI) were analysed with ordinal logistic regression and binary logistic regression with adjustment for trial, cooling method (endovascular, surface or unknown) and age.

Results: Data were obtained for 10 trials (320 participants): COAST-I, COAST-II, COOL AID pilot, COOL AID, COOLIST, HAIS-SE, ICTuS-L, ICTuS-2, MASCOT and MHAIS; IPD were not available for two studies. Trial designs varied and most had a small sample size, mean (SD) age 66 (11.5) years, female 42%, NIHSS 13.4 (5.3), time to treatment 4.5 (1.2) hours, thrombolysis 53%. In patients whose temperature was recorded (n=74), the lowest achieved temperature was in the hypothermia arm: 34.3 o C vs. 36.6 o C (p<0.001). Functional outcome (modified Rankin Scale) at day 90 did not differ between cooling vs. no cooling: n=297 OR 0.93 (95% CI 0.63-1.39, p=0.74). Serious adverse events (n=287) were increased in the cooling arm: 81.5% vs. 65.5% (p<0.001); pneumonia: 30.2% vs. 10.9% (p<0.001) and aspiration: 13.3% vs. 3.5% (p=0.004). There was no difference in death: 17.2% vs. 13.6% (p=0.21).

Conclusion: Hypothermia lowered temperature by 2.3 C, did not alter functional outcome or mortality, but was associated with more SAEs. Larger trials are needed to assess hypothermia in hyperacute stroke.

Seizure-associated central apnea in a rat model: Evidence for resetting the respiratory rhythm and activation of the diving reflex

Respiratory derangements, including irregular, tachypnic breathing and central or obstructive apnea can be consequences of seizure activity in epilepsy patients and animal models. Periods of seizure-associated central apnea, defined as periods >1s with rapid onset and offset of no airflow during plethysmography, suggest that seizures spread to brainstem respiratory regions to disrupt breathing. We sought to characterize seizure-associated central apneic episodes as an indicator of seizure impact on the respiratory rhythm in rats anesthetized with urethane and given parenteral kainic acid to induce recurring seizures. We measured central apneic period onsets and offsets to determine if onset-offset relations were a consequence of 1) a reset of the respiratory rhythm, 2) a transient pausing of the respiratory rhythm, resuming from the pause point at the end of the apneic period, 3) a transient suppression of respiratory behavior with apnea offset predicted by a continuation of the breathing pattern preceding apnea, or 4) a random re-entry into the respiratory cycle. Animals were monitored with continuous ECG, EEG, and plethysmography. One hundred ninety central apnea episodes (1.04 to 36.18s, mean: 3.2±3.7s) were recorded during seizure activity from 7 rats with multiple apneic episodes. The majority of apneic period onsets occurred during expiration (125/161 apneic episodes, 78%). In either expiration or inspiration, apneic onsets tended to occur late in the cycle, i.e. between the time of the peak and end of expiration (82/125, 66%) or inspiration (34/36, 94%). Apneic period offsets were more uniformly distributed between early and late expiration (27%, 34%) and inspiration (16%, 23%). Differences between the respiratory phase at the onset of apnea and the corresponding offset phase varied widely, even within individual animals. Each central apneic episode was associated with a high frequency event in EEG or ECG records at onset. High frequency events that were not associated with flatline plethysmographs revealed a constant plethysmograph pattern within each animal, suggesting a clear reset of the respiratory rhythm. The respiratory rhythm became highly variable after about 1s, however, accounting for the unpredictability of the offset phase. The dissociation of respiratory rhythm reset from the cessation of airflow also suggested that central apneic periods involved activation of brainstem regions serving the diving reflex to eliminate the expression of respiratory movements. This conclusion was supported by the decreased heart rate as a function of apnea duration. We conclude that seizure-associated central apnea episodes are associated with 1) a reset of the respiratory rhythm, and 2) activation of brainstem regions serving the diving reflex to suppress respiratory behavior. The significance of these conclusions is that these details of seizure impact on brainstem circuitry represent metrics for assessing seizure spread and potentially subclassifying seizure patterns.

[Critical illness polyneuropathy and myopathy as neurological complications of sepsis]

Intensive care unit acquired weakness (ICUAW) is a frequent and severe complication of intensive care management. Within ICUAW critical illness polyneuropathy (CIP) and myopathy (CIM) can be differentiated. The major symptom of ICUAW is progressive quadriparesis, which makes weaning from the respirator more difficult, can appear early after admission to an ICU and can often be detected several months after discharge from the ICU. The pathophysiology of ICUAW is multifactorial and complex. Potential therapeutic approaches are the early and sufficient therapy of mulitorgan dysfunction, optimal control of glucose levels as well as early and intensive physiotherapy. This review article discusses the data on incidence, pathophysiology, diagnostic approaches and prognosis of ICUAW.

Laryngospasm, central and obstructive apnea during seizures: Defining pathophysiology for sudden death in a rat model

Seizure spread into the autonomic nervous system can result in life-threatening cardiovascular and respiratory dysfunction. Here we report on a less-studied consequence of such autonomic derangements-the possibility of laryngospasm and upper-airway occlusion. We used parenteral kainic acid to induce recurring seizures in urethane-anesthetized Sprague Dawley rats. EEG recordings and combinations of cardiopulmonary monitoring, including video laryngoscopy, were performed during multi-unit recordings of recurrent laryngeal nerve (RLN) activity or head-out plethysmography with or without endotracheal intubation. Controlled occlusions of a tracheal tube were used to study the kinetics of cardiac and respiratory changes after sudden obstruction. Seizure activity caused significant firing increases in the RLN that were associated with abnormal, high-frequency movements of the vocal folds. Partial airway obstruction from laryngospasm was evident in plethysmograms and was prevented by intubation. Complete glottic closure (confirmed by laryngoscopy) occurred in a subset of non-intubated animals in association with the largest increases in RLN activity, and cessation of airflow was followed in all obstructed animals within tens of seconds by ST-segment elevation, bradycardia, and death. Periods of central apnea occurred in both intubated and non-intubated rats during seizures for periods up to 33s and were associated with modestly increased RLN activity, minimal cardiac derangements, and an open airway on laryngoscopy. In controlled complete airway occlusions, respiratory effort to inspire progressively increased, then ceased, usually in less than 1min. Respiratory arrest was associated with left ventricular dilatation and eventual asystole, an elevation of systemic blood pressure, and complete glottic closure. Severe laryngospasm contributed to the seizure- and hypoxemia-induced conditions that resulted in sudden death in our rat model, and we suggest that this mechanism could contribute to sudden death in epilepsy.

Estimating the Quantitative Demand of NOAC Antidote Doses on Stroke Units

BACKGROUND

The first specific antidote for non-vitamin K antagonist oral anticoagulants (NOAC) has recently been approved. NOAC antidotes will allow specific treatment for 2 hitherto problematic patient groups: patients with oral anticoagulant therapy (OAT)-associated intracerebral hemorrhage (ICH) and maybe also thrombolysis candidates presenting on oral anticoagulation (OAT). We aimed to estimate the frequency of these events and hence the quantitative demand of antidote doses on a stroke unit.

METHODS

We extracted data of patients with acute ischemic stroke and ICH (<24 h after symptom onset) in the years 2012-2015 from a state-wide prospective stroke inpatient registry. We selected 8 stroke units and determined the mode of OAT upon admission in 2012-2013. In 2015, the mode of OAT became a mandatory item of the inpatient registry. From the number of anticoagulated patients and the NOAC share, we estimated the current and future demand for NOAC antidote doses on stroke units.

RESULTS

Eighteen percent of ICH patients within 6 h of symptom onset or an unknown symptom onset were on OAT. Given a NOAC share at admission of 40%, about 7% of all ICH patients may qualify for NOAC reversal therapy. Thirteen percent of ischemic stroke patients admitted within 4 h presented on anticoagulation. Given the availability of an appropriate antidote, a NOAC share of 50% could lead to a 6.1% increase in thrombolysis rate.

CONCLUSIONS

Stroke units serving populations with a comparable demographic structure should prepare to treat up to 1% of all acute ischemic stroke patients and 7% of all acute ICH patients with NOAC antidotes. These numbers may increase with the mounting prevalence of atrial fibrillation and an increasing use of NOAC.

Is Hypothermia Helpful in Severe Subarachnoid Hemorrhage? An Exploratory Study on Macro Vascular Spasm, Delayed Cerebral Infarction and Functional Outcome after Prolonged Hypothermia

Background: Therapeutic hypothermia (TH) is an established treatment after cardiac arrest and growing evidence supports its use as neuroprotective treatment in stroke. Only few and heterogeneous studies exist on the effect of hypothermia in subarachnoid hemorrhage (SAH). A novel approach of early and prolonged TH and its influence on key complications in poor-grade SAH, vasospasm and delayed cerebral ischemia (DCI) was evaluated. Methods: This observational matched controlled study included 36 poor-grade (Hunt and Hess Scale >3 and World Federation of Neurosurgical Societies Scale >3) SAH patients. Twelve patients received early TH (<48 h after ictus), mild (35°C), prolonged (7 ± 1 days) and were matched to 24 patients from the prospective SAH database. Vasospasm was diagnosed by angiography, macrovascular spasm serially evaluated by Doppler sonography and DCI was defined as new infarction on follow-up CT. Functional outcome was assessed at 6 months by modified Rankin Scale (mRS) and categorized as favorable (mRS score 0-2) versus unfavorable (mRS score 3-6) outcome. Results: Angiographic vasospasm was present in 71.0% of patients. TH neither influenced occurrence nor duration, but the degree of macrovascular spasm as well as peak spastic velocities were significantly reduced (p < 0.05). Frequency of DCI was 87.5% in non-TH vs. 50% in TH-treated patients, translating into a relative risk reduction of 43% and preventive risk ratio of 0.33 (95% CI 0.14-0.77, p = 0.036). Favorable functional outcome was twice as frequent in TH-treated patients 66.7 vs. 33.3% of non-TH (p = 0.06). Conclusion: Early and prolonged TH was associated with a reduced degree of macrovascular spasm and significantly decreased occurrence of DCI, possibly ameliorating functional outcome. TH may represent a promising neuroprotective therapy possibly targeting multiple pathways of DCI development, notably macrovascular spasm, which strongly warrants further evaluation of its clinical impact.

EuroHYP-1: European multicenter, randomized, phase III clinical trial of therapeutic hypothermia plus best medical treatment vs. best medical treatment alone for acute ischemic stroke

RATIONALE

Cooling reduced infarct size and improved neurological outcomes in animal studies modeling ischemic stroke, and also improved outcome in randomized clinical trials in patients with hypoxic-ischemic brain injury after cardiac arrest. Cooling awake patients with ischemic stroke has been shown feasible in phase II clinical trials.

PRIMARY AIM

To determine whether systemic cooling to a target body temperature between 34·0 and 35·0°C, started within six-hours of symptom onset and maintained for 24 h, improves functional outcome at three-months in patients with acute ischemic stroke.

DESIGN

International, multicenter, phase III, randomized, open-label clinical trial with blinded outcome assessment in 1500 patients aged 18 years or older with acute ischemic stroke and a National Institutes of Health Stroke Scale score of 6 up to and including 18. In patients randomized to hypothermia, cooling to a target body temperature of 34-35°C will be started within six-hours after symptom onset with rapid intravenous infusion of refrigerated normal saline or a surface cooling technique and maintained for 24 h with a surface or endovascular technique. Patients randomized to hypothermia will receive pethidine and buspirone to prevent shivering and discomfort.

PRIMARY OUTCOME

Score on the modified Rankin Scale at 91 days, as analyzed with ordinal logistic regression and expressed as a common odds ratio.

DISCUSSION

With 750 patients per intervention group, this trial has 90% power to detect 7% absolute improvement at the 5% significance level. The full trial protocol is available at http://www.eurohyp1.eu. ClinicalTrials.gov Identifier: NCT01833312.

Granulocyte colony-stimulating factor does not promote neurogenesis after experimental intracerebral haemorrhage

BACKGROUND

Hematopoietic growth factors have been suggested to induce neuroprotective and regenerative effects in various animal models of cerebral injury. However, the pathways involved remain widely unexplored.

AIMS

This study aimed to investigate effects of local and systemic administration of granulocyte colony-stimulating factor on brain damage, functional recovery, and cerebral neurogenesis in an intracerebral haemorrhage whole blood injection model in rats.

METHODS

Eight-week-old male Wistar rats (n = 100) underwent induction of striatal intracerebral haemorrhage by autologous whole blood injection or sham procedure and were randomly assigned to either (a) systemic treatment with granulocyte colony-stimulating factor (60 μg/kg) for five-days; (b) single intracerebral injection of granulocyte colony-stimulating factor (60 μg/kg) into the cavity; or (c) application of vehicle for five-days. Bromodeoxyuridine-labelling and immunohistochemistry were used to analyze proliferation and survival of newly born cells in the sub-ventricular zone and the hippocampal dentate gyrus. Moreover, functional deficits and lesion volume were assessed until day 42 after intracerebral haemorrhage.

RESULTS

Differences in lesion size or hemispheric atrophy between granulocyte colony-stimulating factor-treated and control groups did not reach statistical significance. Neither systemic, nor local granulocyte colony-stimulating factor administration induced neurogenesis within the dentate gyrus or the sub-ventricular zone. The survival of newborn cells in these regions was prevented by intracerebral granulocyte colony-stimulating factor application. A subtle benefit in functional recovery at day 14 after intracerebral haemorrhage induction was observed after granulocyte colony-stimulating factor treatment.

CONCLUSION

There was a lack of neuroprotective or neuroregenerative effects of granulocyte colony-stimulating factor in the present rodent model of intracerebral haemorrhage. Conflicting results from functional outcome assessment require further research.

Different treatment settings of Granulocyte-Colony Stimulating Factor and their impact on T cell-specific immune response in experimental stroke

BACKGROUND

Cerebral ischemia is associated with infectious complications due to immunosuppression and decreased T lymphocyte activity. G-CSF, which has neuroprotective properties, is known to modulate inflammatory processes after induced stroke. The aim of our study was to investigate the impact of G-CSF in experimental stroke and to compare two different modes of treatment, focusing on circulating T lymphocytes.

METHODS

Cerebral ischemia was induced in Wistar rats by occlusion of the middle cerebral artery, followed by reperfusion after 1h. G-CSF was applied either as a single dose 30 min after occlusion, or daily for seven days. Silver staining was used to determine infarct size. T lymphocytes in the peripheral blood were measured before and 7 days after induced cerebral ischemia by flow cytometry. In addition, migration of CD3-expressing T lymphocytes into the brain was investigated by immunohistochemistry.

RESULTS

Both single dose and daily treatment with G-CSF significantly reduced infarct size. A significant improvement of neurological outcome was only observed after single application of G-CSF. While a decrease in peripheral T lymphocytes was detected seven days after induced stroke, no reduction was observed in the G-CSF-treated groups. Apart from that, G-CSF significantly reduced the number of brain migrated T lymphocytes in both treatment settings as compared to vehicle.

CONCLUSION

A single dose of G-CSF exerted neuroprotective effects in ischemic stroke, which were less pronounced after daily G-CSF application. Both treatment strategies inhibited stroke-induced reduction of T lymphocytes in peripheral blood, which may have contributed to the reduction of infarct size.

Mild prolonged hypothermia for large intracerebral hemorrhage

BACKGROUND

Perihemorrhagic edema (PHE) develops after intracerebral hemorrhage (ICH). It can worsen the clinical situation by its additional mass effect. Therapeutic hypothermia (TH) might be an effective method to control PHE, but has not been sufficiently studied in ICH patients.

METHODS

We report data on n = 25 consecutive patients with large supratentorial ICH (volume > 25 ml) who were treated by mild TH of 35 °C for 8-10 days. Body temperature was controlled by endovascular cooling catheters. We followed the clinical course during hospital stay and measured volumes of ICH and PHE in regularly performed serial cranial computed tomography. Outcome was assessed after 3 and 12 months. These data were compared to a historical group of n = 25 patients with large ICH.

RESULTS

While PHE continuously increased in the historical control group up to day 10, PHE volumes in the hypothermia group remained stable. There was a significant difference from day 3 after symptom onset. Shivering (36 %) and pneumonia (96 %) were the most frequent complications during TH. Mortality rate was 8.3 % in TH versus 16.7 % in the control group after 3 months and 28 versus 44 % after 1 year.

CONCLUSIONS

These data support the promising results of our first case series on TH in large ICH. TH prevents the development of PHE and its complications. Side effects of TH appeared often, but could be treated sufficiently. Therefore, TH might represent a new therapy for PHE after large ICH, but has to be further tested in randomized trials.

Granulocyte colony-stimulating factor in patients with acute ischemic stroke: results of the AX200 for Ischemic Stroke trial

BACKGROUND AND PURPOSE

Granulocyte colony-stimulating factor (G-CSF; AX200; Filgrastim) is a stroke drug candidate with excellent preclinical evidence for efficacy. A previous phase IIa dose-escalation study suggested potential efficacy in humans. The present large phase IIb trial was powered to detect clinical efficacy in acute ischemic stroke patients.

METHODS

G-CSF (135 µg/kg body weight intravenous over 72 hours) was tested against placebo in 328 patients in a multinational, multicenter, randomized, and placebo-controlled trial (NCT00927836; www.clinicaltrial.gov). Main inclusion criteria were ≤9-hour time window after stroke onset, infarct localization in the middle cerebral artery territory, baseline National Institutes of Health Stroke Scale score range of 6 to 22, and baseline diffusion-weighted imaging lesion size ≥15 mL. Primary and secondary end points were the modified Rankin scale score and the National Institutes of Health Stroke Scale score at day 90, respectively. Data were analyzed using a prespecified model that adjusted for age, National Institutes of Health Stroke Scale score at baseline, and initial infarct volume (diffusion-weighted imaging).

RESULTS

G-CSF treatment failed to meet the primary and secondary end points of the trial. For additional end points such as mortality, Barthel index, or infarct size at day 30, G-CSF did not show efficacy either. There was, however, a trend for reduced infarct growth in the G-CSF group. G-CSF showed the expected peripheral pharmacokinetic and pharmacodynamic profiles, with a strong increase in leukocytes and monocytes. In parallel, the cytokine profile showed a significant decrease of interleukin-1.

CONCLUSIONS

G-CSF, a novel and promising drug candidate with a comprehensive preclinical and clinical package, did not provide any significant benefit with respect to either clinical outcome or imaging biomarkers.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00927836.

Lithium alters the morphology of neurites regenerating from cultured adult spiral ganglion neurons

The small-molecule drug lithium (as a monovalent ion) promotes neurite regeneration and functional recovery, is easy to administer, and is approved for human use to treat bipolar disorder. Lithium exerts its neuritogenic effect mainly by inhibiting glycogen synthase kinase 3, a constitutively-active serine/threonine kinase that is regulated by neurotrophin and "wingless-related MMTV integration site" (Wnt) signaling. In spiral ganglion neurons of the cochlea, the effects of lithium and the function of glycogen synthase kinase 3 have not been investigated. We, therefore, set out to test whether lithium modulates neuritogenesis from adult spiral ganglion neurons. Primary cultures of dissociated spiral ganglion neurons from adult mice were exposed to lithium at concentrations between 0 and 12.5 mM. The resulting neurite morphology and growth-cone appearance were measured in detail by using immunofluorescence microscopy and image analysis. We found that lithium altered the morphology of regenerating neurites and their growth cones in a differential, concentration-dependent fashion. Low concentrations of 0.5-2.5 mM (around the half-maximal inhibitory concentration for glycogen synthase kinase 3 and the recommended therapeutic serum concentration for bipolar disorder) enhanced neurite sprouting and branching. A high concentration of 12.5 mM, in contrast, slowed elongation. As the lithium concentration rose from low to high, the microtubules became increasingly disarranged and the growth cones more arborized. Our results demonstrate that lithium selectively stimulates phases of neuritogenesis that are driven by microtubule reorganization. In contrast, most other drugs that have previously been tested on spiral ganglion neurons are reported to inhibit neurite outgrowth or affect only elongation. Lithium sensitivity is a necessary, but not sufficient condition for the involvement of glycogen synthase kinase 3. Our results are, therefore, consistent with, but do not prove lithium inhibiting glycogen synthase kinase 3 activity in spiral ganglion neurons. Experiments with additional drugs and molecular-genetic tools will be necessary to test whether glycogen synthase kinase 3 regulates neurite regeneration from spiral ganglion neurons, possibly by integrating neurotrophin and Wnt signals at the growth cone.

Diagnosis of spontaneous cervical artery dissection may be associated with increased prevalence of posttraumatic stress disorder

BACKGROUND

Receiving information that one has a dissected cervical artery, which can cause a stroke at any time, is obviously traumatic, but details about the psychiatric and psychosocial sequelae are not known. We investigated the prevalence of and risk factors for posttraumatic stress disorder (PTSD) in patients with spontaneous cervical artery dissection (CD) and the impact of PTSD on their psychosocial functioning.

METHODS

Patients admitted because of CD between 2006 and 2010 were retrospectively examined using a diagnostic PTSD measure (Posttraumatic Diagnostic Scale). Patients between 2011 and 2012 were examined prospectively. To identify potential predictors for PTSD, we examined all patients' stress coping strategies (brief COPE inventory), anxiety and depression (Hospital Anxiety and Depression Scale), impairment by preventive medication, time since diagnosis and their neurologic (modified Rankin Scale) and cognitive status. To identify the psychosocial impact of PTSD, we examined quality of life (Short-Form 36).

RESULTS

Data of 47 retrospectively contacted patients and 15 prospectively examined patients were included. Twenty-eight patients (45.2%) met the diagnostic criteria for PTSD. A significantly reduced health-related quality of life (HRQoL) was found in 27 patients (43.5%) for mental health and in 8 patients (12.9%) for physical health. Results of logistic regression analysis revealed that the use of maladaptive coping strategies was predictive of the disorder (P < .0001). Age, sex, mRS score, impairment caused by medication, and time since diagnosis were not predictive for PTSD. The presence of PTSD itself was the only significant predictor for reduced mental HRQol (P = .0004). Age, sex, mRS score, impairment caused by medication, and total Hospital Anxiety and Depression Scale score were not predictive for reduced mental HRQoL.

CONCLUSIONS

PTSD seems to occur frequently in patients with CD and is associated with reduced mental HRQoL. Because the presence of a maladaptive coping style is correlated with PTSD, teaching patients better coping skills might be helpful.

DEcompressive Surgery plus hypoTHermia for Space-Occupying Stroke (DEPTH-SOS): A Protocol of a Multicenter Randomized Controlled Clinical Trial and a Literature Review

Rationale

Although decompressive hemicraniectomy clearly reduces mortality in severe space-occupying middle cerebral artery infarction (so-called malignant middle cerebral artery infarction), every fifth patient still dies in the acute phase and every third patient is left with moderate to severe disability. Therapeutic hypothermia is a neuroprotective and antiedematous treatment option that has shown promising effects in severe stroke. A combination of both treatment strategies may have the potential to further reduce mortality and morbidity in malignant middle cerebral artery infarction, but needs evaluation of its efficacy within the setting of a randomized clinical trial.

Aims

The DEcompressive surgery Plus hypoTHermia for Space-Occupying Stroke (DEPTH-SOS) trial aims to investigate safety and feasibility of moderate therapeutic hypothermia (33°C ± 1) over at least 72 h in addition to early decompressive hemicraniectomy (≤48 hours after symptom onset) in patients with malignant middle cerebral artery infarction.

Design

The DEcompressive surgery Plus hypoTHermia for Space-Occupying Stroke is a prospective, multicenter, open, two-arm (1:1) comparative, randomized, controlled trial.

Study outcomes

The primary end-point is mortality at day 14. The secondary end-points include functional outcome at day 14 and at 12 months follow-up, and complications related to hypothermia.

Discussion

The results of this trial will provide data on safety and feasibility of moderate hypothermia in addition to decompressive hemicraniectomy in malignant middle cerebral artery infarction. Furthermore, efficacy data on early mortality and long-term functional outcome will be obtained, forming the basis of subsequent trials.

[Therapeutic hypothermia in acute brain injury]

Induced therapeutic hypothermia (TH) is defined as a controlled reduction of the core body temperature below the physiological range. While TH is neuroprotective in many different models of brain injury, it is only recommended for patients after cardiopulmonary resuscitation and newborns suffering from perinatal hypoxic-ischemic encephalopathy (HIE). Although a strong association exists between elevated body core temperature (fever) and worsening of outcome, TH has so far not been proven to influence outcome after ischemic stroke, intracerebral hemorrhage or subarachnoidal hemorrhage because of insufficient clinical data. This review summarizes the data on TH for different clinical indications and discusses relevant aspects of its use in neurological intensive care units.

Suppression of dendritic cell functions contributes to the anti-inflammatory action of granulocyte-colony stimulating factor in experimental stroke

Cerebral ischemia provokes an inflammatory cascade, which is assumed to secondarily worsen ischemic tissue damage. Linking adaptive and innate immunity dendritic cells (DCs) are key regulators of the immune system. The hematopoietic factor G-CSF is able to modulate DC-mediated immune processes. Although G-CSF is under investigation for the treatment of stroke, only limited information exists about its effects on stroke-induced inflammation. Therefore, we investigated the impact of G-CSF on cerebral DC migration and maturation as well as on the mediated immune response in an experimental stroke model in rats by means of transient middle cerebral artery occlusion (tMCAO). Immunohistochemistry and quantitative PCR were performed of the ischemic brain and flow cytometrical analysis of peripheral blood. G-CSF led to a reduction of the infarct size and an improved neurological outcome. Immunohistochemistry confirmed a reduced migration of DCs and mature antigen-presenting cells after G-CSF treatment. Compared to the untreated tMCAO group, G-CSF led to an inhibited DC activation and maturation. This was shown by a significantly decreased cerebral transcription of TLR2 and the DC maturation markers, CD83 and CD86, as well as by an inhibition of stroke-induced increase in immunocompetent DCs (OX62⁺OX6⁺) in peripheral blood. Cerebral expression of the proinflammatory cytokine TNF-α was reduced, indicating an attenuation of cerebral inflammation. Our data suggest an induction of DC migration and maturation under ischemic conditions and identify DCs as a potential target to modulate postischemic cerebral inflammation. Suppression of both enhanced DC migration and maturation might contribute to the neuroprotective action of G-CSF in experimental stroke.

Head and neck cooling decreases tympanic and skin temperature, but significantly increases blood pressure

BACKGROUND AND PURPOSE

Localized head and neck cooling might be suited to induce therapeutic hypothermia in acute brain injury such as stroke. Safety issues of head and neck cooling are undetermined and may include cardiovascular autonomic side effects that were identified in this study.

METHODS

Ten healthy men (age 35±13 years) underwent 120 minutes of combined head and neck cooling (Sovika, HVM Medical). Before and after onset of cooling, after 60 and 120 minutes, we determined rectal, tympanic, and forehead skin temperatures, RR intervals, systolic and diastolic blood pressures (BP), laser-Doppler skin blood flow at the index finger and cheek, and spectral powers of mainly sympathetic low-frequency (0.04-0.15 Hz) and parasympathetic high-frequency (0.15-0.5 Hz) RR interval oscillations and sympathetic low-frequency oscillations of BP. We compared values before and during cooling using analysis of variance with post hoc analysis; (significance, P<0.05).

RESULTS

Forehead skin temperature dropped by 5.5±2.2°C with cooling onset and by 12.4±3.2°C after 20 minutes. Tympanic temperature decreased by 4.7±0.7°C within 40 minutes, and rectal temperature by only 0.3±0.3°C after 120 minutes. Systolic and diastolic BP increased immediately on cooling onset and rose by 15.3±20.8 mm Hg and 16.5±13.4 mm Hg (P=0.004) after 120 minutes, whereas skin blood flow fell significantly during cooling. RR intervals and parasympathetic RR interval high-frequency powers increased with cooling onset and were significantly higher after 60 and 120 minutes than they were before cooling.

CONCLUSIONS

Head and neck cooling prominently reduced tympanic temperature and thus might also induce intracerebral hypothermia; however, it did not significantly lower body core temperature. Profound skin temperature decrease induced sympathetically mediated peripheral vasoconstriction and prominent BP increases that are not offset by simultaneous parasympathetic heart rate slowing. Prominent peripheral vasoconstriction and BP increase must be considered as possibly harmful during head and neck cooling.

Cooling in intracerebral hemorrhage (CINCH) trial: protocol of a randomized German-Austrian clinical trial

BACKGROUND

Intracerebral hemorrhage accounts for up to 15% of all strokes and is frequently associated with poor functional outcome and high mortality. So far, there is no clear evidence for a specific therapy, apart from general stroke unit or neurointensive care and management of secondary complications. Promising experimental and pilot clinical data support the use of therapeutic hypothermia after intracerebral hemorrhage.

AIMS

The study aims to determine if therapeutic hypothermia improves survival rates and reduces cerebral lesion volume after large intracerebral hemorrhage compared with conventional treatment.

MATERIAL AND METHODS

The Cooling in IntraCerebral Hemorrhage trial is a prospective, multicenter, interventional, randomized, parallel, two-arm (1 : 1) phase II trial with blinded end-point adjudication. Enrolment: 50 patients (age: 18 to 65 years) with large (25 to 64 ml on cranial computertomography), primary intracerebral hemorrhage of the basal ganglia or thalamus within 6 to 18 h after symptom onset are randomly allocated to therapeutic hypothermia for eight-days or conventional temperature management. In the therapeutic hypothermia group, a target temperature of 35.0°C is achieved by endovascular catheters and followed by slow controlled rewarming. Data analysis is based on the intent-to-treat population. The primary outcome measure of the study is the development in total lesion volume on cranial computertomography (intracerebral hemorrhage plus perihemorrhagic edema on day 8 ± 0.5 and day 1 ± 0.5 after intracerebral hemorrhage) and the mortality after 30 days. Secondary end-points are the in-hospital mortality, mortality, and functional outcome (modified Rankin Scale and Barthel-Index) after 90 and 180 days. Safety measures include any adverse events associated with therapeutic hypothermia.

DISCUSSION

In the face of a lack of evidence-based therapies for patients with large intracerebral hemorrhage, new promising approaches are desperately needed, but need evaluation in randomized controlled trials.

CONCLUSION

The results of Cooling in IntraCerebral Hemorrhage trial are believed to directly influence future therapy of large intracerebral hemorrhage.