Incidence Of Cerebral Ischemia Research Articles

521: CEREBRAL ISCHEMIA AND OUTCOMES WITH RAPID BLOOD PRESSURE LOWERING IN INTRACEREBRAL HEMORRHAGE

Introduction: Guidelines support acute systolic blood pressure (SBP) lowering in intracerebral hemorrhage (ICH) if SBP is between 150 and 220 mmHg to improve outcomes. Recommendations for SBP >220 mm Hg are less clear. A proposed risk is failure of cerebral autoregulation, leading to brain ischemia and poor outcomes. Methods: A single center, retrospective cohort study of adult ICH patients from July 2017 to 2021. Patients from outside of the hospital system, in-hospital ICH, pregnant, or a prisoner were excluded. The primary outcome was incidence of cerebral ischemia in patients with SBP >220 mmHg (high) vs. 150-219 mmHg (low), assessed through percent SBP lowering and evaluation of radiographic imaging during admission. Secondary outcomes included poor neurologic status with mRS of 4 to 6 at discharge. Results: Of the 393 patients included, median (IQR) premorbid mRS was 0 in both groups, median (IQR) NIHSS was high; 16 (8, 23) vs. low; 13 (5, 19), p < 0.01. The median (IQR) presenting SBP was high; 236 (225, 246) mmHg vs. low; 180 (166, 197) mmHg. SBP goal was achieved in the first 24 hours in high; 86% vs. low; 77%, p = 0.09. Median (IQR) change in SBP 12 hours after arrival was high; -98 (-112, -83) mmHg vs. low; -47 (-62, -25) mmHg (p < 0.01) with a percent change in 12 hour SBP of 41% vs. 25%, p < 0.01. Significance persisted at 18 and 24 hours after arrival. Both groups had a mean (SD) of 7 (4) radiographic images obtained during admission. The median (IQR) time to detection of ischemia was high; 2.8 (1.4, 5.7) days vs. low; 3.1 (1.2, 6.6) days, p = 0.6. Presence of ischemic insults did not differ in the regression model based on presenting SBP groups [HR 0.57 (0.25, 1.3) p = 0.81] or percent change in SBP > or < 25% at 24 hours [HR 0.83 (0.41, 1.69) p = 0.61]. Poor neurologic outcome at discharge was present in high; 82% vs. low; 69% of patients (p = 0.07). Higher admission ICH score (p < 0.01) and NIHSS (p < 0.01) was associated with a poor outcome in the regression model. Conclusions: These results suggest there was no difference in the development of ischemic changes based on presenting SBP or percent change in the SBP. Poor neurologic outcome was associated with higher NIHSS and ICH score on admission in the analysis. These results will need to be confirmed in a randomized study.

The beneficial roles of apelin-13/APJ system in cerebral ischemia: Pathogenesis and therapeutic strategies.

The incidence of cerebral ischemia has increased in the past decades, and the high fatality and disability rates seriously affect human health. Apelin is a bioactive peptide and the ligand of the G protein-coupled receptor APJ. Both are ubiquitously expressed in the peripheral and central nervous systems, and regulate various physiological and pathological process in the cardiovascular, nervous and endocrine systems. Apelin-13 is one of the subtypes of apelin, and the apelin-13/APJ signaling pathway protects against cerebral ischemia by promoting angiogenesis, inhibiting excitotoxicity and stabilizing atherosclerotic plaques. In this review, we have discussed the role of apelin-13 in the regulation of cerebral ischemia and the underlying mechanisms, along with the therapeutic potential of the apelin-13/APJ signaling pathway in cerebral ischemia.

Prophylaxis with a multicomponent nutraceutical abates transient cerebral ischemia/reperfusion injury.

The effect of a multicomponent nutraceutical on cerebral ischemia/reperfusion injury in male Wistar rats was investigated. Animals were administered with the nutraceutical, Trévo™, for 7days before 30min of bilateral common carotid artery occlusion-induced cerebral ischemia and 24hr of reperfusion. Behavioral assessment, biochemical estimations in the brain cortex, striatum, and hippocampus, and hippocampal histopathological evaluation were carried out after treatments. Results showed that ischemia/reperfusion-induced motor and cognitive deficits were abated in rats pretreated with Trévo™. Additionally, prophylaxis with Trévo™ blunted ischemia/reperfusion-induced redox stress, proinflammatory events, disturbances in neurotransmitter metabolism, mitochondrial dysfunction, and histoarchitectural aberrations in the discreet brain regions. In summary, supplementation with Trévo™ provided neuroprotection to rats against transient cerebral ischemia/reperfusion injury and could be explored as a promising approach in stroke prevention. PRACTICAL APPLICATIONS: There is a worldwide increase in the incidence of cerebral ischemia or stroke. Although an advanced health care system and effective control of risk factors have led to the declining incidence in developed nations, a definitive cure for stroke remains elusive and the situation is growing worse in developing nations. The results of the present study revealed that supplementation with Trévo™ ameliorated neurobehavioral, neurochemical, and histopathological consequences of brain ischemia/reperfusion injury and could, therefore, be beneficial in stroke prevention and management.

The clinical application of transcranial doppler ultrasonography in severe traumatic brain injury post decompressive craniectomy

Objective To explore the clinical application of transcranial doppler ultrasonography (TCD) in severe traumatic brain injury (sTBI)post decompressive craniectomy. Methods A retrospective study was conducted on 58 patients with sTBI who were admitted to Neurosurgical Intensive Care Unit of Tangdu Hospital, the Fourth Military Medical University From January 2015 to October 2016. All patients underwent hematoma evacuation, decompressive craniectomy and placement of intracerebral pressure (ICP) probe. The parameters of cerebral blood flow including mean velocity (Vmean), end of diastolic (Vedv) and pulsatility index (PI) in sTBI patients were measured by TCD post operation to assess the cerebral blood supply. Results The trend of Vmean and Vedv manifested U-shaped mode during the next 7 days, reaching the lowest levels [(72.5±22.6) cm/s and (43.6±19.8) cm/s, respectively] on day 3. There was significant difference in the value of Vmean between day 3 and day 1, 2, 5, 6, 7 (all P<0.05). There was significant difference in the value of Vedv between day 3 and day 1, 2, 6, 7 (all P<0.05). The trend of pulsatility index (PI) and intracranial pressure (ICP) showed parabolic shape during the next 7 days, reaching the highest level [(1.5±0.7) and (17.2±4.5)mmHg, respectively] on day 4. Significant difference was observed in ICP between day 4 and day 1, 2, 3, 6, 7 (P<0.05). The incidence of cerebral hyperemia showed the trend of declining during the next 7 days. There was significant difference in cerebral hyperemia between day 1 and day 5, 6, 7 (all P<0.05). The incidence of cerebral ischemia was up to 36.2% (12/58) on day 4, and it was significantly higher than that on day 1 (P<0.05). The incidence of cerebral vasospasm showed the rising trend and reached the highest level (15.5%) on day 6, which had significant difference compared with the incidences on day 1, 2 and 3 (all P<0.05). Conclusion TCD, as a noninvasive, portable, easy-to-use monitoring tool, could help effectively evaluate postoperative changes of cerebral hemodynamics in patients with sTBI. Key words: Craniocerebral trauma; Ultrasonography, doppler, transcranial; Decompressive craniectomy

Abstract TP349: Incidence of Cerebral Ischemia Associated Seizures in Patients With Narrowing or Occlusion of the Ipsilateral Internal Carotid or Middle Cerebral Artery: The EC/IC Bypass Study

Background: Cerebral ischemia associated seizures are well recognized in patients with internal carotid or middle cerebral artery stenosis or occlusion although the incidence is not well documented. Methods: We analyzed the data that was collected on 1377 patients with recent hemisphere strokes, retinal infarction, or transient ischemic attacks with atherosclerotic narrowing or occlusion of the ipsilateral internal carotid or middle cerebral artery who were enrolled in the EC/IC Bypass Study. The patients were followed for an average of 55.8 months and any seizures related to cerebral ischemia based on clinical and imaging criteria were ascertained. We calculated the relative risk in pre-defined patient subgroups: Age (&lt;55 and ≥55 years), gender, presenting symptom (transient ischemic attack and ischemic stroke), allocated treatment (bypass surgery and medical treatment), site of stenosis/occlusion (internal carotid artery and middle cerebral artery), and presence or absence of hypertension and diabetes mellitus. Results: A total of 64 patients experience one or more cerebral ischemia associated seizures during follow up: first seizure was focal and generalized in 33 and 31 patients, respectively. The incidence of cerebral ischemia associated seizures was 1.7 per 100 person observation years. The relative risk of seizures was higher among patients aged &lt;55 years (relative risk 1.36, 95% confidence interval [CI] 0.8-2.2), women (relative risk 1.1, 95% CI 0.6-2.1), with stroke as presenting symptom (RR 1.9, 95% CI 1.1-3.3), with medical group as allocated treatment (RR 1.2,95%CI 0.7-2.0), with middle cerebral artery as site of stenosis/occlusion(RR 1.13, 95% C.I 0.6-2.0), with diabetes mellitus (RR 1.7, 95% CI 0.96-3.0) or hypertension (RR 1.1, 95% CI 0.7-1.8). Conclusions: We provide the incidence of and factors affecting occurrence of cerebral ischemia associated seizures in patients with narrowing or occlusion of the ipsilateral internal carotid or middle cerebral artery

Cerebral Perfusion Pressure Based Management of Traumatic Brain Injury

Cerebral perfusion pressure (CPP) is the difference between mean arterial pressure (MAP) and intracranial pressure (ICP). Traditionally, management of traumatic brain injury (TBI) depended mainly on ICP control strategies. Based on the evidence that cerebral ischemia plays a major role in causing poor neurological outcome in traumatic brain injury (TBI) and cerebral blood flow autoregulation is shifted rightward in these patients, Rosner and colleagues suggested a treatment protocol that advocated maintaining a CPP higher than 70 mmHg, by controlling intracranial hypertension and increasing MAP by using hypervolemia and vasoactive agents, if required. Following the initial studies that showed better outcomes than other contemporary series, a number of studies tried to define the critical CPP in TBI. The threshold values suggested by these studies varied widely between 50 mmHg and higher than 70 mmHg. While there is no controversy about the adverse effects of low CPP, the major concerns in CPP-based therapy are a possible increase in brain oedema with a decrease in intracranial compliance and the systemic complications associated with the interventions used to achieve high CPP. There is no major evidence to suggest that high CPP increases ICP or decreases intracranial compliance. One major randomized trial comparing CPP-based and ICP-based strategies showed a major reduction in the incidence of cerebral ischemia with cerebral blood flow (CBF)-targeted therapy. But the same study also documented a five-fold increase in acute respiratory distress syndrome in patients managed by CPP-based strategy, and similar outcomes between the treatment groups. Following this, the brain trauma foundation (BTF) lowered the suggested CPP threshold to 60 mmHg from its original recommendation of 70 mmHg. Current research is focusing on the possibility of defining the optimal CPP for any given patient based on more objective measures of cerebral oxygenation, metabolism and CBF autoregulation. Critical thresholds of CPP in children remain ill-understood.

Monitoring of activated coagulation time in carotid endarterectomy

Background The objective of the present study was to evaluate the efficacy of monitoring activated coagulation time (ACT) during carotid endarterectomy (CEA) in reducing surgical risks and complications. Methods A total of 175 consecutive patients who had CEA between July 2002 and January 2004 were studied. Activated coagulation time was monitored during the procedure in all patients. The results were compared with the data reported in the literature, and with those obtained in 2 previous series, totaling 1924 patients treated at the same service before the use of ACT. Results Only 4 of the 175 patients had cerebral ischemia, with 3 of them almost completely recovering during hospitalization. Significant morbidity was 0.6% and mortality was 0.6%. No statistically significant difference in the incidence of cerebral ischemia or death was observed between symptomatic and asymptomatic patients. In the 2 previous series used for comparison, operated by the same author, we found 0.7% and 0.8% of significant morbidity and 1.4% and 2.6% of mortality, respectively. Most series in the literature have shown a higher significant morbidity than the present one, mainly in symptomatic patients. The incidence of hematoma in the present series was 5.7%, only 3 (1.7%) of them being significant. No increase in the frequency of hematomas was observed in cases where heparin was not reversed or in those using a shunt. In the 2 other previous series, the incidence of hematomas was 1.5% and 3.6%. Conclusions Activated coagulation time monitoring during CEA was effective in evaluating the level of heparinization of patients during surgery and the immediate postoperative period. The comparison of the present series with the literature and with the previous series of the same service, before the use of ACT, permits also to conclude that the control of the level of heparinization seems to reduce the risk of perioperative and immediate postoperative ischemia. In addition, ACT monitoring also seems to be effective in diminishing the risk of postoperative cervical hematoma.

1267 HSP70-2 polymorphism as a risk factor for carotid plaque rupture and cerebral ischaemia in old type 2 diabetes-atherosclerotic patients

Patients with type 2 diabetes mellitus (NIDDM) are at risk for macrovascular disease complications, such as myocardial infarction (MI) or stroke from plaque rupture. Cytokines play a key role in plaque vulnerability. IFN-γ inhibits collagen synthesis thereby affecting plaque stability. High IL-6, TNF-α, and dyslipidemia are risk factors for thrombosis. Abnormal increments of HSP70 in atherosclerotic plaques might lead to plaque instability and rupture caused by chronic inflammation, which up-regulates the expression of pro-inflammatory cytokines (IL-6 and TNF-α) in human monocytes. Studies of a polymorphic PstI site lying in the coding region at position 1267 of the HSP70-2 gene have shown that the BB genotype is associated with NIDDM. We screened 60 old NIDDM patients with carotid stenosis and 107 old healthy controls for 1267 HSP70-2 polymorphism in order to establish if an association with plaque frailty exists. Different genotypic distributions were observed between patients and healthy controls. An increased relative risk was associated with the B allele ( p = 0.0107; odds ratio = 1.861). HSP70-2, IL-6, IFN-γ, TNF-α gene expressions within the plaques and serum levels of triglyceride, total cholesterol and LDL cholesterol were tested from patients stratified according to their B+ (AB and BB) and B− (AA) genotypes. Plaque morphology (soft or fibrous-calcified) and the incidence of cerebral ischaemia were also assessed. B+ patients showed increased HSP70-2, IL-6, IFN-γ, TNF-α and dyslipidemia as compared to B− carriers. The frequency of soft plaques increased in B+ in comparison to B− patients (67% versus 13%; odds ratio 13.0, p = 0.0006). A higher frequency of cerebral ischaemia (ictus or transient ischaemic attack (TIA)) was present in B+ than in B− genotype (53% versus 20%; odds ratio 4.57, p < 0.05) Hence, 1267 HSP70-2 polymorphism may be of use in identifying B+ NIDDM patients at risk for carotid plaque rupture and cerebral ischaemia.

Controlled and uncontrolled thrombocytosis.Its clinical role in essential thrombocythemia

Only two of 19 patients with spontaneously evolving essential thrombocythemia remained asymptomatic in a 421 patient-month observation. The rest of the patients showed hemorrhagic diathesis (four patients), nonspecific neurological semiology (two patients), and occlusive vascular illness in cerebral, myocardic, arterial, and often multiple locations (total, 12 patients). Peripheral neuropathy was found in five of 10 patients studied. In this series the incidence of cerebral ischemia in the uncontrolled condition was 180 times higher than the epidemiologic expectancy in a population not affected by the disorder. Of 35 ischemic attacks, 22 occurred when the platelet count was more than than 1000 X 10(9)/l, 13 when the count ranged from 650 to 990 X 10(9)/l, and none occurred at counts of less than 650 X 10(9)/l. In contrast, therapeutic control of the thrombocytosis caused all complications to disappear. These findings point out the danger of the natural course of the illness and justify active therapy. At the same time they call into question some of the most commonly used criteria in the diagnosis of essential thrombocythemia.