Biomedical subjects

Christiana E Hall

Publications and source records attributed to Christiana E Hall.

6 recordsLinked to original sources

PubMed2006

Telestroke: extending stroke expertise into underserved areas.

Telestroke systems offer the opportunity to extend stroke-care expertise into rural and underserved areas. These systems are being used to give alteplase to patients with stroke in previously underserved areas safely, effectively, and rapidly. Telestroke will probably play a large part in improving the quality of stroke care and in enrolling patients into clinical trials in rural and community hospitals. One such telestroke system, REACH (remote evaluation of acute ischaemic stroke), is a low-cost, web-based system that allows the consultant to access the system from work, home, or on the road. REACH is presently being used to give alteplase and guide acute stroke care in eight rural community hospitals in Georgia.

Female↗

PubMed2005

New era for management of primary hypertensive intracerebral hemorrhage.

This discussion focuses on recent reports relevant to improved understanding and future directions in the management of intracerebral hemorrhage (ICH). Prevention is possible with adequate treatment of hypertension; microbleeds, apolipoprotein genotype, and cholesterol treatment have been examined in relation to ICH risk. Hematoma products, matrix metalloproteinases, inflammatory markers, and means to attenuate injury have also received attention. The multifaceted character of perihematomal edema has been further defined but evidence for perihematomal ischemia remains elusive. New data on acute blood pressure reinforces the need for a clinical trial. With the lack of efficacy found in the International Surgical Trial in Intracerebral Hemorrhage (ISTICH), a landmark surgical trial, emphasis is shifting to minimally invasive and catheter/thrombolytic-based technologies for clot evacuation. On the medical side, activated factor VII has been shown to control hemorrhage growth. Looking forward, stem cell therapies for ICH are under investigation and some outcome studies are shedding new rays of hope.

Antihypertensive Agents↗

PubMed2005

New horizons for primary intracerebral hemorrhage treatment: experience from preclinical studies.

Intracerebral hemorrhage (ICH) remains a major medical problem, for which there is no effective treatment. However, extensive experimental and clinical research carried out in recent years has brought to light new exciting ideas for novel potential treatments. First, it was well documented that the management of hypertension helps to prevent new and recurrent ICH. Also, development of new guidelines for management of hypertension after the onset of the ICH may help in more effective ICH treatment. Existing contemporary data collected from preclinical studies indicates that ICH-induced inflammation represents a key factor leading to secondary brain damage, suggesting that some anti-inflammatory approaches can be used to treat hemorrhagic stroke. In this article, beyond discussing implications related to hypertension, we will summarize important (but not all) new discoveries connecting the role of inflammation to ICH pathology. Selected aspects of inflammatory response including the role of cytokines, transcription factor nuclear factor-kB, microglia activation, astrogliosis, and complement activation will be introduced. We will also discuss the role for reactive oxygen species and metalloproteinases in ICH pathogenesis and introduce basic knowledge on the nature of ICH-induced cell death including apoptosis. Potential targets for intervention and translation will be discussed.

Animals↗

PubMed2004

Aggressive mechanical clot disruption: a safe adjunct to thrombolytic therapy in acute stroke?

BACKGROUND AND PURPOSE: This study evaluated the safety and efficacy of aggressive mechanical clot disruption (AMCD) in acute stroke patients with persisting middle cerebral artery (MCA) or internal carotid artery (ICA) occlusion after thrombolytic therapy. METHODS: Retrospective case series were used from a prospectively collected stroke database on consecutive acute ischemic stroke patients treated with intra-arterial (IA) thrombolytics and mechanical clot disruption during a 5-year interval. Thrombolytic dosage, endovascular techniques, immediate and final recanalization rates, symptomatic hemorrhage, mortality, and outcome were determined. RESULTS: Thirty-two patients received AMCD. Median baseline National Institutes of Health Stroke Scale (NIHSS) score was 18, and median time to initiation of IA treatment was 261 minutes from symptom onset. ICA occlusion was noted in 16 patients and MCA occlusion in 16 patients: 22 received combined IV/IA thrombolytics, 3 received IV thrombolytics, 6 received IA thrombolytics, and 1 patient received no thrombolytics before AMCD. No immediate periprocedural complications were noted. Immediate recanalization was achieved in 38% (50% MCA, 25% ICA) and final recanalization in 75% (88% MCA, 63% ICA) of patients. Favorable outcome occurred in 19 (59%) patients, symptomatic cerebral hemorrhage in 3 (9.4%) patients, and mortality in 4 (12.5%) patients. CONCLUSIONS: AMCD can be performed safely with comparable intracerebral hemorrhage and mortality rates to other IA therapies even after use of intravenous thrombolytics in selected patients. Early deployment of this technique leads to immediate recanalization in one third of patients. AMCD may potentially shorten the time to flow restoration and improve overall recanalization rates achieved with IA therapy.

Adult↗

PubMed2004

Ischemic stunning of the brain: early recanalization without immediate clinical improvement in acute ischemic stroke.

BACKGROUND AND PURPOSE: Early arterial recanalization (ER) with intravenous tissue plasminogen activator (tPA) can lead to dramatic clinical recovery, whereas some patients do not experience immediate clinical improvement. METHODS: Consecutive patients received tPA 0.9 mg/kg IV within 3 hours after symptom onset. All had M1 or M2 middle cerebral artery occlusions on pretreatment transcranial Doppler. Patients were continuously monitored for 2 hours after bolus. ER was defined as the Thrombolysis in Brain Ischemia intracranial flow increase by >or=1 grade. Stroke severity (National Institutes of Health Stroke Scale [NIHSS]) and recovery (modified Rankin Scale) were assessed independently of transcranial Doppler. RESULTS: One hundred twenty patients (mean age, 68+/-15 years; 63 women; median NIHSS, 17; range, 5 to 29; 90% with >or=10 points) received tPA at a median of 120 minutes, 50% within the first 2 hours. ER was observed in 73 patients (32 complete, 41 partial). No immediate clinical changes (n=23) or worsening (by 1 to 6 points on NIHSS, n=4) was observed in 37% of ERs (nonresponders). Complete ER was found in 8 of these 27 patients. At 24 hours, 22 of 27 patients (82%) had persisting deficits of NIHSS >or=10 points, yet 37% of these nonresponders (10 of 27) still achieved good outcome (modified Rankin score, 0 to 2) at 3 months. Among nonresponders with good outcome, 100% had detectable residual flow signals, and 70% had compensatory flow diversion on prebolus transcranial Doppler compared with 65% and 29% of nonresponders with poor outcome (P<0.05). Compared with responders (n=46), nonresponders had similar prebolus median NIHSS of 16 to 17 points, bolus times of 120 to 132 minutes, median speed of thrombolysis (30 minutes), and ER times of 190 to 193 minutes after onset. Reocclusion occurred in 3 of 4 patients with clinical worsening, 30% of other nonresponders, and 22% of responders. Symptomatic hemorrhage rate was 4% in both groups. At 3 months, mortality was 33% in nonresponders compared with 9% in responders (P=0.001). CONCLUSIONS: After successful arterial ER with tPA therapy, lack of early clinical changes or worsening is relatively common (37%) and appears to be independent of time to tPA bolus or reperfusion. However, with tPA alone, at least one third of these nonresponders still achieved good outcomes at 3 months, suggesting the possibility of a "stunned brain" syndrome with delayed recovery. Several different mechanisms may potentially account for this phenomenon.

Acute Disease↗

PubMed2004

Treatment of acute intracerebral hemorrhage with epsilon-aminocaproic acid: a pilot study.

INTRODUCTION: Up to 40% of primary intracerebral hemorrhages (ICHs) expand within the first 24 hours (natural history). The authors aimed to study the safety and preliminary efficacy of epsilon-aminocaproic acid (EACA) in halting ICH enlargement. METHODS: Consecutive patients with hematoma volumes ranging from 5 to 80 mL were recruited within 12 hours of ICH onset. A total of 5 g EACA was infused during 1 hour and then 1 g/hour for 23 hours. Hematoma volume was compared on baseline, and 24-48-hour brain imaging. Consecutive untreated patients underwent the same imaging protocol. RESULTS: Three of the first five patients treated had HE>33% of their baseline volume. HE occurred in two of the nine untreated patients. The 80% confidence interval for HE in the treated patients was 32-88%. No thrombotic or other serious adverse events were attributed to EACA. CONCLUSION: It is unlikely that the rate of HE in patients given EACA within 12 hours of ICH is less than the natural history rate, although this treatment appears to be safe.

Acute Disease↗