Hypothermia in acute stroke

Acute supratentorial ischemic stroke: when surgery is mandatory

Acute occlusion of middle cerebral artery (MCA) leads to severe brain swelling and to a malignant, often fatal syndrome. The authors summarize the current knowledge about such a condition and review the main surgical issues involved. Decompressive hemicraniectomy keeps being a valid option in accurately selected patients.

Hypothermia reduces perihemorrhagic edema after intracerebral hemorrhage

BACKGROUND AND PURPOSE

The prognosis of spontaneous intracerebral hemorrhage (sICH) is poor because of the mass effect arising from the hematoma and the associated peri-hemorrhagic edema, leading to increased intracranial pressure. Because the efficacy of surgical and anti-edematous treatment strategies is limited, we investigated the effects of mild induced hypothermia in patients with large sICH.

METHODS

Twelve patients with supratentorial sICH >25 mL were treated by hypothermia of 35 degrees C for 10 days. Evolution of hematoma volume and perifocal edema was measured by cranial CT. Functional outcome was assessed after 90 days. These patients were compared to patients (n=25; inclusion criteria: sICH volume >25 mL, no acute restriction of medical therapy on admission) from the local hemorrhage data bank (n=312). Side effects of hypothermia were analyzed.

RESULTS

All patients from both groups needed mechanical ventilation and were treated in a neurocritical care unit. All hypothermic patients (mean age, 60+/-10 years) survived until day 90, whereas 7 patients died in the control group (mean age, 67+/-7 years). Absolute hematoma size on admission was 58+/-29 mL (hypothermia) compared to 57+/-31 mL (control). In the hypothermia group, edema volume remained stable during 14 days (day 1, 53+/-43 mL; day 14, 57+/-45 mL), whereas edema significantly increased in the control group from 40+/-28 mL (day 1) to 88+/-47 mL (day 14). ICH continuously dissolved in both groups. Pneumonia rate was 100% in the hypothermia group and 76% in controls (P=0.08). No significant side effects of hypothermia were observed.

CONCLUSIONS

Hypothermia prevented the increase of peri-hemorrhagic edema in patients with large sICH.

Antiedema therapy in ischemic stroke

Life-threatening, space-occupying brain edema occurs in up to 10% of patients with supratentorial infarcts and is traditionally associated with a high mortality rate of up to 80%. Management of these patients is currently being changed to an earlier and more aggressive treatment regimen. Early surgical decompression has recently been proven effective to reduce mortality and increase the number of patients with a favorable outcome in randomized controlled trials and is now the "antiedema" therapy of first choice for patients with large middle cerebral artery infarction aged 60 years or younger. Several medical treatment strategies have been proposed to control brain edema and reduce intracranial pressure, including different osmotherapeutics, hyperventilation, tromethamine, hypothermia, and barbiturate coma. None of these treatments is supported by level 1 evidence of efficacy in clinical trials, and some of them may even be detrimental. Preliminary results on hypothermia for space-occupying hemispheric infarction are encouraging, but far from definitive.

Akuttherapie des Schlaganfalls

This article covers three major topics of acute stroke therapy: extension of the time window for thrombolysis with desmoteplase, decompressive surgery after malignant middle cerebral artery infarction, and the effect of hemostatic therapy with recombinant activated factor VII (rFVIIa) in patients with spontaneous primary intracerebral hemorrhage. Thrombolytic therapy with recombinant tissue or tissue-type plasminogen activator is still the only approved acute stroke therapy within a 3-h time window. Imaging-based patient selection seems to help extending this time window. After promising results of two phase II trials with the thrombolytic agent desmoteplase in an extended time window after acute ischemic stroke, the DIAS-II study was reconducted in Europe, North America, and Australia as a phase III trial. First results of the included 186 patients are shown. Surprisingly, patients treated with desmoteplase had no better outcome than placebo-treated patients, and there was increased mortality in the high-dose group. Among all stroke subtypes, space-occupying malignant middle cerebral artery is one with the poorest prognosis. Most patients die within a few days due to the development of massive brain edema, despite maximum intensive care. Decompressive hemicraniectomy represents a much more effective therapy for the treatment of local brain swelling. However, until recently this method was highly controversial. Here we present the results of the randomized trials published in 2007 and discuss their relevance for acute therapy. Hematoma growth occurs within 4 h in one third of patients who suffer from intracerebral hemorrhage. Prospective, placebo-controlled, multicenter trials have shown that intravenous application of rFVIIa reduces volume increase. We present preliminary results of the latest phase III trial (FAST: recombinant factor VIIa in acute hemorrhagic stroke), which tried to find whether the hemostatic effect will translate into clinical effect.

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.

Treatment of cerebral edema

BACKGROUND

Cerebral edema is a potentially devastating complication of various acute neurologic disorders. Its successful treatment may save lives and preserve neurologic function.

REVIEW SUMMARY

Different pathophysiological mechanisms are responsible for the formation of cytotoxic and vasogenic edema. Yet, these 2 types of edema often coexist and their treatment tends to overlap, with the exception of corticosteroids, which should be only used to ameliorate vasogenic edema. Currently available to control brain swelling include osmotic agents (with emphasis on mannitol and hypertonic saline solutions), corticosteroids, hyperventilation, sedation (propofol, barbiturates), neuromuscular paralysis, hypothermia, and surgical interventions. This article discusses the indications, advantages, and limitations of each treatment modality following an evidence-based approach.

CONCLUSIONS

The therapy for brain edema remains largely empirical. More research aimed at enhancing our understanding of the pathophysiology of cerebral edema is needed to identify new and more effective forms of treatment.

Treatment of massive cerebral infarction

Stroke is the third leading cause of death in the United States, with a person dying every 3 minutes of a stroke. Massive ischemic stroke accounts for 10% to 20% of ischemic strokes, has traditionally been associated with a high mortality and morbidity, and requires a unique management strategy. Recent advances in management, fueled by an increased understanding of the pathophysiology, may help decrease mortality and improve outcomes. Rapid access to reperfusion therapies remains the most critical element of stroke care and the cornerstone of therapy. This article focuses on newer therapies, including osmotic therapy, hypothermia, maintained normothermia, strict glycemic control, induced hypertension, and hemicraniectomy, all of which show promise for reducing mortality and improving functional outcome. These interventions have become integrated into neurologic intensive care units around the world. They are complicated, require a high level of expertise, and carry a significant learning curve. In order for these new management techniques to be effective, an expedited, aggressive, meticulous, and potentially prolonged medical management approach is needed. To accomplish this there is a growing need for focused specialists in the areas of neurointensive care and stroke.