Monitoring Of Intracranial Pressure In Ischemic Stroke Patients

Patients with massive cerebral infarction may require ICP monitoring, as this may help to guide therapy and predict outcome. Schwab et al.102 evaluated 48 patients with massive hemispheric infarctions and clinical signs of elevated ICP. They found that ICP measurements correlated well with the patient's clinical status, CT findings and outcome, although they did not find a significant effect of their therapies for elevated ICP on patient outcomes. Multiple methods of monitoring ICP are avail...

Conclusion

The efficacy of IV thrombolysis in patients with moderate-to-severe strokes due to proximal arterial occlusions is restricted by several factors, including the relatively short therapeutic window, poor recanalization rates as the clot burden increases, restrictive eligibility criteria, and the risk of intracerebral hemorrhage. Endovascular techniques improve the rates of recanalization in this patient population, and appear to increase the likelihood of a good functional outcome. Intravenous...

Implementation Of An Acute Stroke Team And Acute Stroke Protocols

The overwhelming prerogative, in thrombolysis for acute ischemic stroke, is the need for rapid, yet complete, evaluation of potential therapeutic candidates within the 3-hour treatment window. Time is the acute stroke clinician's worst enemy.33 The acute stroke protocol should begin at the first of point of contact with the healthcare system the call to an ambulance dispatcher. Stroke symptoms should be recognized and given high priority for dispatch. Emergency medical technicians (EMTs) should...

Adjunctive Therapy

Fibrinolytic agents have prothrombotic properties as well. The plasmin generated by thrombolysis leads to the production of thrombin, which is a potent platelet activator and converts fibrinogen to fibrin. Indeed, studies have shown early reocclusion in as many as 17 of the patients treated with IAT 17 and 34 of the patients treated with IV rt-PA.63 Therefore, a strong rationale exists for the adjuvant use of antithrombotic agents. Systemic anticoagulation with IV heparin during the...

Trials Comparing Heparin to Aspirin in Acute Stroke

The Heparin in Acute Embolic Stroke Trial (HAEST) was a multicenter, randomized trial of the effect of LMWH (dalteparin 100 IU kg sc twice daily) or aspirin (160 mg once daily) for the acute treatment of 449 patients with ischemic stroke and atrial fibrillation (AF).13 The primary outcome was the rate of recurrent stroke within 14 days. No difference in rates of early recurrence (8.5 dalteparin treated vs. 7.5 aspirin treated) or good 3-month functional outcome was found. The frequency of early...

Stroke Historical Perspectives And Future Directions

Recent years have witnessed increasing recognition and interest in stroke as a major public health problem. However, stroke is an ancient disease. Imhotep, the founder of Egyptian medicine, described stroke in one of the world's earliest medical documents, the Edwin Smith papyrus, around 3000 BC. More detailed description of this condition followed in AD 1600s when Thomas Willis identified the arterial supply of the brain, the circle of Willis,'' and used the term apoplexy to describe stroke....

Medical Measures to Control Cerebral Edema

Hyperventilation reduces ICP by reducing CBF. Carbon dioxide is a potent cerebral vasodilator, and thus vasoconstriction is induced by rapidly decreasing the pCO2 (thereby concomitantly increasing the CSF pH), subsequently reducing the entry of blood into the cerebral circulation and lowering the ICP. The effect is almost immediate, reducing ICP typically within minutes. However, it is short lived, and may theoretically result in worsening of the cerebral infarction volume secondary to...

Telestroke In Clinical Practice Networks of Care

TeleStroke networks (e.g., Fig. 10.3) are now well established in Germany and Ontario, as well as in Georgia, Massachusetts, Texas, California, and Maryland in the United States. One of the first large series of TeleStroke consultations was described in southern Germany, where seven rural hospitals were linked to a stroke unit in FIGURE 10.3 Regional maps depicting TeleStroke Networks. Two hospitals in the TEMPiS network in Bavaria (Germany) provide acute stroke expertise to 12 community...

References

Tissue plasminogen activator for acute ischemic stroke. The National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group. N Engl J Med 1995 333 1581-1587. 2. Marler JR, Tilley BC, Lu M, Brott TG, Lyden PC, Grotta JC, Broderick JP, Levine SR, Frankel MP, Horowitz SH, Haley Jr. EC, Lewandowski CA, Kwiatkowski TP. Early stroke treatment associated with better outcome the NINDS rt-PA stroke study. Neurology 2000 55 1649-1655. 3. Alberts MJ, Hademenos G, Latchaw RE, Jagoda A,...

Cardiac Complications In Ischemic Stroke Patients

Acute stroke patients are at high risk for cardiac events, including myocardial infarction (MI) and dysrhythmias from autonomic derangement, particularly with strokes involving the insular cortex. Although the precise mechanisms and triggers for this have yet to be elucidated, it appears that there is a predominance of sympathetic activity associated with strokes involving the right hemisphere.115 Seizures that originate from the left temporal lobe may be more commonly associated with...

Hemicraniectomy for Refractory Edema

Surgical management of ischemic stroke is discussed in further detail in Chapter 6, but worth brief mention here is the use of hemicraniectomy for massive hemispheric cerebral infarction. In patients who are at high risk for herniation, or who are refractory to maximal medical therapy, decompressive hemicraniectomy (DC), with or without partial temporal lobectomy, may be useful in selected patients. DC alleviates tissue shifts and rapidly reduces ICP, allowing for an adequate CPP to perfuse...

Blood Pressure Management

Manipulation of blood pressure becomes necessary in many ischemic stroke patients, as patients with ongoing ischemia and fixed stenotic arterial lesion s may require blood pressure management to feed the ischemic penumbra. Conversely, patients with cerebral edema may require blood pressure lowering to reduce the detrimental effect of increased cerebral blood flow CBF . In the normal human brain, CBF is kept relatively constant by the mechanism of cerebral autoregulation. This applies throughout...

Trials of Heparin in Acute Ischemic Stroke

Placebo-Controlled Trials of UFH, LMWH, and Heparinoids The International Stroke Trial 1ST 8 was a randomized, placebo-controlled trial of UFH 5000 or 12,500 IU twice daily and aspirin 300 mg in 19,435 unselected patients with acute stroke within 48 hours of symptom onset. Because of limited availability of neuroimaging, 33 of participants were enrolled with suspected but not proven ischemic stroke, some of whom may have suffered primary intracerebral hemorrhage ICH . TABLE 7.1 Commonly used...

Stroke Subtype Predicts Outcome

Patients with large vessel atherothrombotic stroke have been reported to have worse short- and long-term survival as compared to other subtypes of stroke.5-11 In a population-based study from Rochester Minnesota, only 24 of patients classified as atherothrombotic were independent during the period of worst deficit and 50 were independent at 1 year.9 Large vessel atherothrombotic stroke patients also have the highest rate of recurrent stroke.6,10,11 Cardioembolic strokes may also have poor...

Efficiency of Thrombolytic Administration

In the first 27 months of our own TeleStroke experience,30 26 consultations were requested 12 began within 3 hours of symptom onset. Eight of these 12 patients had acute ischemic stroke, of which 2 were not treated due to mild deficits. Three were diagnosed with TIA or migraine, and one with a subdural hematoma not detected at the local facility. For the 12 acute cases for whom rapid diagnosis and management was essential, we determined the mean times from symptom onset to start of TeleStroke...

Thrombolytic Agents

Fibrolase Cleaving Fibrin

Plasminogen Activators These drugs act by converting the inactive proenzyme, plasminogen, into the active enzyme, plasmin. Plasmin can digest fibrinogen, fibrin monomers, and cross-linked fibrin as found in a thrombus into fibrin degradation products. These agents vary in stability, half-life, and fibrin selectivity. The thrombolytics that have been reported for use in stroke IAT include urokinase UK , alte-plase, reteplase, pro-urokinase, and streptokinase SK .19,54 In general, the...

Special Circumstances Cerebellar Infarction

Cerebellar Stroke Hydrocephalus

Cerebellar infarction poses a particularly dangerous situation, as the posterior fossa acts as its own compartment, creating the possibility of brainstem compression, early herniation or obstructive hydrocephalus for ischemic strokes that swell, conditions that can develop suddenly and be fatal if not treated expeditiously. Certainly, patients with progressive brainstem signs from a compressive lesion should be considered at risk for fatal herniation and nearly always warrant a surgical...

Endovascular Thrombectomy

Phenox Clot Retriever

Mechanical thrombectomy is a promising novel technique in interventional stroke treatment. The devices differ with regard to where they apply force on the thrombus, taking either a proximal approach with aspiration devices see section on thromboaspiration below or a distal approach with basket- or snare-like devices. A study comparing the effectiveness of these two approaches Vasco35 vs. Catch device in a swine stroke model demonstrated that the proximal device allowed fast repeated...

Extracranialintracranial Arterial Bypass

EC-IC arterial bypass involves the use of general anesthesia, open craniotomy, and end-to-side anastomosis of the superficial temporal artery to a branch of the middle cerebral artery MCA Fig. 6.1 . Currently, this technique is being used primarily in the setting of intracranial aneurysm therapy, moyamoya disease, and FIGURE 6.1 CT angiography of an EC-IC bypass, showing the new intracranial course of the right superficial temporal artery, anastamosed to the middle cerebral artery M2 segment....

Management Of Cerebral Edema Associated With Ischemic Stroke

There are three types of ischemic strokes that are more commonly associated with an increased risk of morbidity and mortality moderate-to-large cerebellar strokes, large cerebral hemispheric strokes, and moderate-to-large strokes in the middle cranial fossa, where a theoretical compartment exists that may lead to early herniation if untreated. Kasner et al.45 evaluated 201 patients with large MCA strokes, and found several factors to be associated with the development of malignant or fatal...

Identifying The Vascular Lesion

Cta Absent Right Pcom

Ischemic stroke occurs because of impairments in microvascular perfusion of affected brain tissue. However, the vascular event that results in impaired perfusion often occurs in a macroscopically visible vessel. Imaging studies that can study these vessels provide several kinds of important information to the stroke neurologist. First, by definitively demonstrating a vascular lesion that could be responsible for ischemic symptoms, vascular imaging can help to cement the diagnosis of an acute...

Thromboaspiration

Suction thrombectomy or thromboaspiration through either a microcatheter21,95 or a guiding catheter96 may be an option for fresh nonadhesive clot. As discussed above, aspiration devices have the advantage of causing less embolic events and vasos-pasm however, the more complex design of these devices makes them more difficult to navigate into the intracranial circulation. FIGURE 4.5 A 72-year-old man with medical history remarkable for hypertension and dyslipidemia presented with posterior...

Decompressive Hemicraniectomy

Decompressive hemicraniectomy is primarily intended to treat the high intracranial pressure associated with massive MCA infarction and subsequent swelling Fig. 6.3 . Focal areas of ischemia may result when intracranial pressure is greater than 20 mmHg, and global ischemia can occur when intracranial pressure exceeds 50mmHg.33 Therefore, removal of a large part of the calvarium, theoretically reducing intracranial hypertension, ongoing ischemia, and preventing swollen tissue from displacing...

Establishing The Diagnosis Of Ischemic Stroke

Insular Ribbon Sign

Recent years have seen the emergence of successful treatment strategies for ischemic stroke, but these are most effective only when initiated within several hours after stroke onset. Therefore, extremely rapid diagnosis and initiation of treatment are critical in avoiding death or severe disability. Unfortunately, there are a variety of other clinical conditions that may mimic the presentation of acute ischemic stroke. These include intracranial hemorrhage, seizure, sepsis, cardiogenic syncope,...