Neurochemical monitoring of therapeutic effects in large human MCA infarction

BACKGROUND AND PURPOSE

Cerebral microdialysis is an invasive monitoring tool allowing analysis of various substances derived from the extracellular space in brain tissue such as glutamate, glycerol, lactate, and pyruvate. In order to assess the potential effects of hemicraniectomy, hypothermia and conservative therapy on these substances, we used neurochemical monitoring with microdialysis in large human stroke patients.

METHODS

This is an open, prospective observational study in 24 patients with large MCA infarction undergoing either hypothermia (33 degrees C), hemicraniectomy, or maximum conservative therapy. Microdialysis probe placement was aimed at the peri-infarct tissue within 24 h after stroke onset. Glutamate, glycerol, pyruvate, and lactate were analyzed every 60 min. Measurements of two consecutive days were pooled for statistical analysis.

RESULTS

Average glutamate concentrations in patients treated with hemicraniectomy (5.3 +/- 0.5 micromol/l, P < 0.0001; n = 6) and hypothermia (14.5 +/- 3.6 micromol/l, P < 0.0001; n = 14) were significantly lower than in conservatively treated patients (68.3 +/- 5.2 micromol/l; n = 4). Glycerol concentration was significantly lower in patients treated by hypothermia (111 +/- 17 micromol/l; P < 0.0001) and hemicraniectomy (138 +/- 8 micromol/l; P < 0.0001) as compared to conservatively treated patients with 612 +/- 27 micromol/l. The lactate-pyruvate ratio was significantly lower both in the hypothermia (16.2 +/- 3.3) and hemicraniectomy groups (31.3 +/- 1.5) than in the conservative treatment group (56 +/- 2.9).

CONCLUSION

Microdialysis allows bed-side monitoring of neuroprotective effects of stroke rescue therapies such as hypothermia and hemicraniectomy. Rescue of peri-infarct tissue and/or prevention of secondary ischemic injury could be associated with a lower mortality in invasively treated patients.

Safety and outcome after thrombolysis in stroke patients with mild symptoms

BACKGROUND

Thrombolytic therapy is frequently withheld in patients with minor stroke symptoms. However, recent studies demonstrate that a substantial proportion of these patients dies or remains permanently disabled because of underestimation of symptom severity at baseline or secondary deterioration. We aimed to assess the safety and outcome of thrombolysis therapy in patients with minor but disabling stroke symptoms.

METHODS

32 patients presenting with mild symptoms were treated with intravenous recombinant tissue-type plasminogen activator between April 2006 and April 2008. Data were extracted from a prospectively collected database. Baseline demographic data, and clinical, laboratory and imaging findings were analyzed. Outcome was assessed using the modified Rankin Scale (mRS) score at 3 months and was dichotomized into favorable (mRS 0-1) versus unfavorable (mRS 2-6).

RESULTS

In the majority of patients, the left hemisphere was affected, with aphasia representing the most common symptom leading to treatment decision. The frequency of perfusion lesion (46%) and vessel occlusion (35%) at baseline was high but had no effect on the outcome at 3 months in our series of treated patients. Outcome was favorable in 94% of patients, and 47% recovered without any persisting symptom. Only one asymptomatic and no symptomatic hemorrhage was observed.

CONCLUSION

Our data support current guidelines and international licenses which give no lower National Institutes of Health Stroke Scale (NIHSS) limit for intravenous thrombolysis (IVT). Considering the accumulating evidence that the natural course in patients with mild symptoms is not as favorable as often assumed and taking the low risk of bleeding in those patients into account, patients with mild but disabling symptoms should be treated with IVT regardless of their baseline NIHSS score.

Influence of intraventricular fibrinolytic therapy with rt-PA on the long-term outcome of treated patients with spontaneous basal ganglia hemorrhage: a case-control study

Over the recent years, fibrinolytic agents have been tested for intraventricular clot fibrinolysis (IVF). Compared with patients who did not receive IVF, administration of rt-PA induces rapid resorption of intraventricular blood and normalization of cerebrospinal fluid (CSF) circulation resulting in a reduced 30-day mortality and beneficial short-term outcome after 3 months. Our objective was to analyze possible influences of IVF on the long-term outcome after 12 months. Based on a prospective data base, patients with ganglionic supratentorial hematoma with additional intraventricular hemorrhage and occlusive hydrocephalus (n = 135) were isolated. Twenty-seven patients received IVF. To design a case-control study, we carefully matched 22 controls without IVF with regard to hematoma volume, Graeb score, Glasgow Coma Scale on admission and age (five patients remained unmatchable). We determined clinical and imaging parameters by reviewing the medical records and CT scans of all included patients. Outcome after 12 months was evaluated using the modified Rankin scale (mRS). One multivariate regression analysis was performed to determine predisposing factors for outcome. IVF significantly reduced Graeb score during treatment (eight on admission, three after IVF, one prior to discharge in the treated group versus 8/6/2 in patients without IVF). In patients with IVF requirement, a second external ventricular drainage (EVD) and a ventriculoperitoneal (VP) shunt were reduced (P = 0.08) and the incidence of a lumbar drainage was significantly higher (P < 0.01), whilst the overall time of extra-corporal CSF drainage was comparable. EVD associated complications were equal in both groups. Overall long-term outcome was poor but no significant differences were found between patients with and without IVF (mRS 4-6: 12/22 (54%) in patients with and 13/22 (59%) in patients without IVF; P = 0.81). The five excluded patients with IVF were similar to the 22 included ones with respect to imaging findings and outcome. The multivariate analysis revealed age and baseline hematoma volume, but not IVF to significantly impact the outcome. In accordance with previous studies, IVF hastened clot lysis and reduced the need for repeated EVD exchanges and permanent shunting. However, despite these advantages, IVF did not influence long-term outcome after 12 months. The results of the prospective randomized trial (Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage) need to be awaited.

Acute onset of fatal vegetative symptoms: unusual presentation of adult Alexander disease

Since genetic analysis of the GFAP gene for the diagnosis of adult Alexander disease (AD) has been established in 2001, several cases of both sporadic and familial cases of AD have been described. Except for one patient, all subjects revealed glial fibrillary acidic protein (GFAP) mutations, and clinical progression of symptoms, mainly bulbar and pseudobulbar, were moderate. Here we report on a patient with acute onset of vegetative symptoms, rapid progression, and death within 2 months. Although histology and final magnetic resonance imaging (MRI) were characteristic of AD, sequencing of the encoding GFAP gene revealed no mutation. We believe that this case report expands the so far known clinical spectrum and MRI dynamics of adult AD, and suggest that analysis of the coding part of GFAP may be inconclusive in rare cases. In such patients, only histology may lead to definitive diagnosis.

Long-term outcome after thrombolysis in telemedical stroke care

BACKGROUND

IV thrombolysis represents the most effective acute stroke therapy. However, it is almost exclusively performed in stroke centers and is not available in most community areas. The Telemedical Pilot Project for Integrative Stroke Care (TEMPiS) was started in February 2003. Twelve community hospitals with no or very limited stroke thrombolysis experience and two stroke centers were connected via a network providing online neurologic examination and transfer of neuroradiologic scans. Following recently published preliminary results on acute phase safety of telethrombolysis, the present study reports on its long-term functional outcome.

METHODS

Modified Rankin Scale (mRS), Barthel Index (BI), and mortality rate were prospectively collected 3 and 6 months after IV thrombolysis in patients of community network hospitals (telemedical group) and the stroke centers. Values of 95/100 for the BI and 0/1 for the mRS were defined as a favorable outcome.

RESULTS

Over the first 22 months, 170 patients were treated with tPA in the telemedical hospitals and 132 in the stroke center hospitals. Mortality rates were 11.2% vs 11.5% at 3 months (p = 0.55) and 14.2% vs 13% at 6 months (p = 0.45). A good functional outcome after 6 months was found in 39.5% of the telemedical hospitals vs 30.9% of the stroke centers (p = 0.10) for the mRS and 47.1% vs 44.8% (p = 0.44) regarding the BI.

CONCLUSIONS

Mortality rates and functional outcomes for telemedicine-linked community hospitals and stroke centers were similar and comparable to the results from randomized trials.

Ischaemic stroke: acute management, intensive care, and future perspectives

Recently, a number of developments in the acute management of stroke have necessitated active involvement of neurocritical care. This review focuses on the immediate care, including intensive care, that may make a difference to the patient outcome. Recent research, that highlights the importance of acute management of stroke in terms of thrombolysis, thrombolytic agents, decompressive surgery, and hypothermia, has been reviewed.