Symptomatic vasospasm diagnosis after subarachnoid hemorrhage: evaluation of transcranial Doppler ultrasound and cerebral angiography as related to compromised vascular distribution

OBJECTIVE: To evaluate the reliability of transcranial Doppler ultrasound in detecting symptomatic vasospasm in patients after aneurysmal subarachnoid hemorrhage and monitoring response after hypertensive and endovascular treatments. DESIGN: Retrospective chart review. SETTING: Neurosciences critical care unit in a tertiary-care university hospital. PATIENTS: All patients admitted to a neurosciences critical care unit with the diagnosis of subarachnoid hemorrhage between January 1990 and June 1997. INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: We reviewed transcranial Doppler ultrasound data of 199 patients; 55 had symptomatic vasospasm. Clinical symptoms and corresponding vascular distributions were identified, as was angiographic vasospasm (n = 35). The sensitivity and specificity of transcranial Doppler ultrasound for anterior circulation vessels were calculated by using a mean cerebral blood flow velocity criterion of >120 cm/sec. Clinical diagnosis of symptomatic vasospasm was used as the standard to determine sensitivity and specificity of transcranial Doppler ultrasound and cerebral angiography. The sensitivity of transcranial Doppler ultrasound for anterior circulation in patients with symptomatic vasospasm was 73% with a specificity of 80%. The sensitivity of cerebral angiography was 80%. For individual vessels, the sensitivity and specificity of transcranial Doppler ultrasound were middle cerebral artery, 64% and 78%; anterior cerebral artery, 45% and 84%; and internal carotid artery, 80% and 77%, respectively. The mean times for symptomatic and transcranial Doppler ultrasound signs of vasospasm presentation were 6.4 +/- 2 and 6.1 +/- 3 days, respectively. In patients without symptomatic vasospasm, the mean time for mean cerebral blood flow velocities >120 cm/sec was 7.0 +/- 3 days (p <.05). Symptomatic vasospasm also was associated with thickness of clot on head computed tomography scan and rapidly increasing mean cerebral blood flow velocities. Transcranial Doppler ultrasound signs of vasospasm improved after endovascular treatment in 30 patients. CONCLUSIONS: The reliability of transcranial Doppler ultrasound was better at detecting high mean cerebral blood flow velocities in patients with symptomatic vasospasm related to middle cerebral and internal carotid artery distributions than for anterior cerebral artery distribution. Transcranial Doppler ultrasound was as sensitive as cerebral angiography at detecting symptomatic vasospasm. High mean cerebral blood flow velocities can be apparent before the presence of symptomatic vasospasm. Daily transcranial Doppler ultrasound monitoring could provide early identification of patients with aneurysmal subarachnoid hemorrhage who are at high risk for symptomatic vasospasm and may be helpful at following success of endovascular treatment.     

Xenon-CT and transcranial Doppler in poor-grade or complicated aneurysmatic subarachnoid hemorrhage patients undergoing aggressive management of intracranial hypertension

Objective To evaluate whether elevated flow velocimetry values are associated with critically reduced cerebral blood flow values in deeply sedated patients with acute aneurysmatic subarachnoid hemorrhage and in whom the detection of clinical vasospasm is not feasible. Design Retrospective analysis of prospectively collected data.Setting Neurosurgical and trauma patients in an intensive care unit in a regional hospital.Patients and participants Twenty-nine patients in the acute phase following subarachnoid hemorrhage who were sedated and ventilated for elevated intracranial pressure, transcranial Doppler vasospasm, or respiratory failure and were studied with at least a coupled xenon-CT/transcranial Doppler study.Measurements and results Combined measurement and comparison of cerebral blood flow by means of xenon-CT and of mean velocity by means of transcranial Doppler in middle cerebral artery territories. The case mix studied was consistent with patients' predominantly poor grade and with a complicated course. The results suggest that in sedated patients flow velocity and measured cortical mixed cerebral blood flow are not correlated, and, more specifically, that flow velocities values above 120 or 160 cm/s and Lindegaard index above 3 are not associated with an ischemic regional cerebral blood flow. Conversely, as many as 55% of the xenon-CT studies were associated with hyperemia.Conclusions In patients with elevated intracranial pressure, mean middle cerebral artery flow velocity or Lindegaard Index does not help to detect critical cerebral blood flow nor elevated cerebral blood flow.     

Accuracy of transcranial Doppler sonography for predicting cerebral infarction in aneurysmal subarachnoid hemorrhage

PURPOSE: To evaluate the accuracy of transcranial Doppler (TCD) sonography using different criteria for predicting cerebral infarction due to symptomatic vasospasm. METHODS: We retrospectively evaluated the clinical and radiologic data of consecutive patients admitted with acute aneurysmal subarachnoid hemorrhage (SAH) in the anterior cerebral circulation between January 2001 and June 2002. TCD sonographic examinations were performed on alternate days up to 20 days after admission. Cerebral infarction was defined on CT as a new hypodensity in the vascular distribution with corresponding clinical symptoms. Vasospasm was diagnosed as mild or severe when TCD sonography revealed a mean blood flow velocity (MBFV) greater than 120 and 180 cm/s in the middle or anterior cerebral artery and in the intracranial part of the internal carotid artery, respectively. RESULTS: A total of 93 patients with aneurysmal SAH in the anterior cerebral circulation were included. Vasospasm was demonstrated by TCD sonography in 60 patients (64.5%) and was shown via multivariable logistic regression analysis to be predictive of cerebral infarction (OR 3.11, 95% CI 1.46-6.59), with an 82.6% and 69.6% sensitivity, a 41.4% and 77.1% specificity, a 31.7% and 50.0% positive predictive value, and an 87.9% and 88.5% negative predictive value when the MBFV was greater than 120 and 180 cm/s, respectively. CONCLUSIONS: Vasospasm on TCD was found to be predictive of symptomatic cerebral infarction on CT, but its positive predictive value remained low despite the adoption of restrictive TCD criteria for vasospasm.     

Continuous measurement of cerebral blood flow velocity using transcranial Doppler reveals significant moment-to-moment variability of data in healthy volunteers and in patients with subarachnoid hemorrhage

OBJECTIVE: The reliability of intermittent transcranial Doppler has not been accepted widely because of problems with interobserver variability and lack of accuracy. The limitations of intermittent transcranial Doppler are thought to be overcome by continuous measurement systems. However, little published data exist on their accuracy, feasibility, and moment-to-moment variability. In this study we aimed to determine the time-related variability of continuous transcranial Doppler signal from volunteers and patients with subarachnoid hemorrhage and to examine the feasibility, ease of use, and quality of data generated from continuous transcranial Doppler for the detection of vasospasm. DESIGN: Prospective observational study. SETTING: Intensive care unit in a tertiary referral center. SUBJECTS: Ten volunteers and eight patients with aneurysmal subarachnoid hemorrhage. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The middle cerebral artery blood flow velocities were recorded continuously from both patients and volunteers. The moment-to-moment variability of continuously recorded data was calculated. There was a wide range of velocity measurements in both volunteers and patients. There was a significant moment-to-moment variability in both volunteers (-31% to 58%) and in patients (-38% to 78%). There was a greater number of observations exceeding 10% moment-to-moment variability in the patient group with regard to systolic and diastolic velocities compared with volunteers (8% vs. 2%, p < .001). There was a trend toward a longer duration of good quality data in volunteers compared with patients (98 +/- 0.5% vs. 96 +/- 9%). CONCLUSIONS: Continuous measurement of cerebral blood flow velocities revealed a significant moment-to-moment variability in both patients and in volunteers, the magnitude of which was greater in the patients. The clinical implications of these findings are discussed.     

Vasospasm Surveillance With Transcranial Doppler Sonography in Subarachnoid Hemorrhage

The use of transcranial Doppler monitoring for the diagnosis of vasospasm in subarachnoid hemorrhage is backed by national guidelines. However, it remains poorly used across neurologic intensive care units in the United States. This current practice article uses 2 clinical vignettes to illustrate the simplicity and logic behind routine daily surveillance of vasospasm with transcranial Doppler sonography in patients with subarachnoid hemorrhage, in preference to other modalities.     

Hyperemia following aneurysmal subarachnoid hemorrhage: incidence,diagnosis, clinical features,and outcome

OBJECTIVE: Hyperemia is a known phenomenon after aneurysmal subarachnoid hemorrhage, but only a few reports describe and analyze hyperemia in these patients. This could be the result of diagnostic difficulties in order to identify elevated cerebral blood flow; thus, it seems that hyperemia could be an underdiagnosed clinical state. The aim of the study was to evaluate this phenomenon in comparison with clinical outcome and imaging data in order to describe the frequency of hyperemia after subarachnoid hemorrhage and maybe improve clinical diagnosis. DESIGN: Retrospective analysis of our cerebral blood flow and transcranial Doppler sonography data bank. SETTING:. Neurosurgical/Anesthesiological intensive care unit University of Regensburg, Regensburg, Germany. PATIENTS AND PARTICIPANTS: A total of 37 patients were included (24 women and 13 men). All patients suffered from aneurysmal subarachnoid hemorrhage. MEASUREMENTS AND RESULTS: Standard transcranial Doppler ultrasonography, as well as the Xenon(133) clearance technique for cerebral blood flow measurements, was employed. We observed 37 increases of flow velocities in 37 patients according to Doppler ultrasonography. In order to distinguish between ischemia and hyperemia a Xenon(133) regional cerebral blood flow examination was performed. Global hyperemia was detected in 5 patients (14%). Hyperemia correlated only to favorable outcome ( p=0.01) and fewer ischemic lesions in the computed tomography ( p<0.05). CONCLUSION: The results indicate that while global hyperemia is a frequent phenomenon that cannot be detected by standard Doppler ultrasonography or clinical examination, hyperemic cerebral blood flow values following aneurysmatic subarachnoid hemorrhage are correlated to favorable outcome.     

Role of transcranial Doppler in optimizing treatment of cerebral vasospasm in subarachnoid hemorrhage

This study was undertaken to evaluate the role of transcranial Doppler ultrasonography in arterial blood pressure management during hypervolemia/hypertension/ hemodilution therapy in patients with vasospasm from subarachnoid hemorrhage and correlate this data with neurologic outcome. The study included 18 adult patients, Hunt and Hess grades III-IV. Complete neurologic assessment was performed. Transcranial Doppler indices were calculated by standard formulas. On the basis of our results, resistance area product can be used to estimate the optimal arterial blood pressure in hypervolemia/hypertension/hemodilution therapy. An increase in the cerebral blood flow index was associated with better performance on neurologic examination. Estimated cerebral perfusion pressure from transcranial Doppler data analysis showed poor correlation with cerebral perfusion pressure derived from direct measurement of intracranial pressure in patients with cerebral vasospasm (rho = 0.15; 95% CI, 0.11-0.39; P = .2590).     

Cerebrovascular dynamics with head-of-bed elevation in patients with mild or moderate vasospasm after aneurysmal subarachnoid hemorrhage.

BACKGROUND: In patients with aneurysmal subarachnoid hemorrhage, elevation of the head of the bed during vasospasm has been limited in an attempt to minimize vasospasm or its sequelae or both. Consequently, some patients have remained on bed rest for weeks. OBJECTIVES: To determine how elevations of the head of the bed of 20 degrees and 45 degrees affect cerebrovascular dynamics in adult patients with mild or moderate vasospasm after aneurysmal subarachnoid hemorrhage and to describe the response of mild or moderate vasospasm to head-of-bed elevations of 20 degrees and 45 degrees with respect to variables such as grade of subarachnoid hemorrhage and degree of vasospasm. METHODS: A within-patient repeated-measures design was used. The head of the bed was positioned in the sequence of 0 degrees -20 degrees -45 degrees -0 degrees in 20 patients with mild or moderate vasospasm between days 3 and 14 after aneurysmal subarachnoid hemorrhage. Continuous transcranial Doppler recordings were obtained for 2 to 5 minutes after allowing approximately 2 minutes for stabilization in each position. RESULTS: No patterns or trends indicated that having the head of the bed elevated increases vasospasm. As a group, there were no significant differences within patients at the different positions of the head of the bed. Utilizing repeated-measures analysis of variance, P values ranged from .34 to .97, well beyond .05. No neurological deterioration occurred. CONCLUSIONS: In general, elevation of the head of the bed did not cause harmful changes in cerebral blood flow related to vasospasm.     

Assessment of middle cerebral artery diameter after aneurysmal subarachnoid hemorrhage by transcranial color-coded duplex sonography.

This study examined if vasospasm after aneurysmal subarachnoid hemorrhage could be visualized by middle cerebral artery (MCA) diameter changes in transcranial color-coded duplex sonography (TCCS). Comparative measurements between mean blood velocity (MBV) and MCA diameter were carried out in 17 patients in 76 instances. At two depth ranges (proximal, 60 55 mm: distal, 50-45 mm) two observers assessed the MCA diameter as indicated by the visualized blood flow column. At both points of measurement, the diameter differences between the two observers were within the ? 2 S.D. range of the mean difference indicating interobserver agreement. In 17 instances, MBV was > 120 cm/s indicating vasospasm but MBV did not correlate with absolute or relative diameter changes. MCA diameter assessment in TCCS seems reproducible. Because TCCS imaging is influenced by several factors comparative angiographic studies are necessary to clarify the TCCS findings.     

持续腰穿外引流防治脑血管痉挛的观察与护理

目的　探讨持续腰穿外引流对防治脑血管痉挛的疗效与护理。方法　 6 4例动脉瘤性蛛网膜下腔出血患者 ,在超早期行电解可脱卸弹簧圈 (guglielmidetachablecoil,GDC)栓塞术后 ,34例行持续腰穿外引流 ,另 30例行间断腰穿作为对照组 ,2组同样给予常规的尼莫通及 3H治疗 ,通过临床症状及经颅多谱勒超声 (TCD)判断血管痉挛的发生率及严重程度。结果　引流组发生症状性血管痉挛 4例 ,对照组 8例 ,其中 1例遗留神经功能障碍。引流组的脑血管痉挛发生率明显低于对照组。无引流相关并发症发生。结论　腰穿持续外引流可以有助于清除蛛网膜下腔积血 ,严密观察及合理护理对于减少并发症是必要的。     

经颅多普勒超声对动物实验性蛛网膜下腔出血后脑血管痉挛观察

本文通过对大耳白兔实验性蛛网膜下腔出血术前、术后兔基底动脉的血流峰速的观察发现,(1)动物实验性蛛网膜下腔出血后第3天为脑血管痉挛发生的高峰。(2)经颅多普勒超声对蛛网膜下腔出血后脑血管痉挛的诊断、监测、治疗时机的选择及疗效的评价有很大的临床使用价值。     

Vasospasm after head injury studied by transcranial Doppler sonography

During the past 2 years cerebral blood flow velocity was measured serially first of all in the middle cerebral arteries and in the bifurcation of the carotid arteries, less frequently in the other basal arteries by transcranial Doppler sonography in 36 head injured patients selected from 87 cerebral contusions and intracranial haematomas. Raised flow velocity referring to cerebral vasospasm was observed in 14 (40%) of 36 cases. Vasospasm developed between the 2nd and 8th days in the basal arteries, never on the first day. It was classified as slight (over 120 cm/sec) and sever (over 160 cm/sec) in the case of vasospasm lasting for several days. Development of vasospasm could be justified in 6 from 14 control angiographies. Authors' observations are compared with some literary data of traumatic vasospasm. The theoretical significance and practical usefulness of transcranial Doppler sonography in the study and follow up of the blood flow of the injured brain, especially in traumatic vasospasm, are emphasized.     

Clinical review: Prevention and therapy of vasospasm in subarachnoid hemorrhage

Vasospasm is one of the leading causes of morbidity and mortality following aneurysmal subarachnoid hemorrhage (SAH). Radiographic vasospasm usually develops between 5 and 15 days after the initial hemorrhage, and is associated with clinically apparent delayed ischemic neurological deficits (DID) in one-third of patients. The pathophysiology of this reversible vasculopathy is not fully understood but appears to involve structural changes and biochemical alterations at the levels of the vascular endothelium and smooth muscle cells. Blood in the subarachnoid space is believed to trigger these changes. In addition, cerebral perfusion may be concurrently impaired by hypovolemia and impaired cerebral autoregulatory function. The combined effects of these processes can lead to reduction in cerebral blood flow so severe as to cause ischemia leading to infarction. Diagnosis is made by some combination of clinical, cerebral angiographic, and transcranial doppler ultrasonographic factors. Nimodipine, a calcium channel antagonist, is so far the only available therapy with proven benefit for reducing the impact of DID. Aggressive therapy combining hemodynamic augmentation, transluminal balloon angioplasty, and intra-arterial infusion of vasodilator drugs is, to varying degrees, usually implemented. A panoply of drugs, with different mechanisms of action, has been studied in SAH related vasospasm. Currently, the most promising are magnesium sulfate, 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors, nitric oxide donors and endothelin-1 antagonists. This paper reviews established and emerging therapies for vasospasm.     

Transcranial Doppler ultrasonography: clinical applications in cerebrovascular disease

Transcranial Doppler ultrasonography was introduced in 1982 as a noninvasive procedure for assessment of the intracranial cerebral circulation. The lightweight and portable equipment used for transcranial Doppler examination facilitates its use in the bedside assessment of critically ill hospitalized patients and outpatients. Clinical applications include the diagnosis of vasospasm in patients with subarachnoid hemorrhage, assessment of intracranial collateral flow in patients with extracranial arterial occlusive disease, detection of intracranial arterial stenosis, identification of the feeding arteries of arteriovenous malformations and monitoring the hemodynamic effects of their treatment, confirmation of the clinical diagnosis of brain death, intensive-care unit monitoring of brain-injured patients, and intraoperative and postoperative monitoring of neurosurgical patients. Transcranial Doppler technology is also providing new insights into the pathophysiologic mechanisms of a variety of cerebrovascular conditions. Clinicians will find transcranial Doppler technology most helpful if they have a specific question about the status of the intracranial circulation. Further investigations may expand the clinical and research utility of this technology.     

蛛网膜下腔出血患者症状性脑血管痉挛的预测与研究

目的研究蛛网膜下腔出血患者中症状性脑血管痉挛的预测.方法76例蛛网膜下腔出血患者均行脑血管造影、TCD检查、Fisher量表评分,同时对性别、年龄、吸烟、高血压等因素进行分析,研究上述因素是否可对临床症状性脑血管痉挛进行预测.结果脑血管造影及TCD检查时有脑血管痉挛、Fisher分型Ⅲ型、高龄患者临床脑血管痉挛的发生率显著高于对照组,而性别、吸烟、高血压不是脑血管痉挛的危险因素.结论脑血管造影、TCD检查、Fisher量表可以进对临床症状性脑血管痉挛进行预测.     

经颅彩色多普勒超声评价外伤性蛛网膜下腔出血患者大脑中动脉血管痉挛

目的探讨经颅彩色多普勒超声(TCCS)在评价外伤性蛛网膜下腔出血患者大脑中动脉痉挛程度中的作用。方法对经CT确诊的外伤性蛛网膜下腔出血患者100例,采用TCCS观察大脑中动脉彩色血流束的走行、方向、有无局部充盈缺损和色彩混叠,频谱多普勒检测大脑中动脉收缩期峰值血流速度(VMCA)及同侧颈内动脉入颅段的血流速度(VICA),计算Lindegaard指数=VMCA/VICA。检查时间分别在脑外伤后1~3d、10d、14d,每次均测量3次取平均值。根据有无脑血管痉挛症状,分为有症状和无症状组,并对两组血流参数进行比较分析。结果外伤后3~7d蛛网膜下腔出血患者开始出现不同程度的脑血管痉挛症状,以6~10d最显著,2周以后逐渐减轻,其中外伤后10d35例符合大脑中动脉痉挛的诊断标准;有症状组VMCA和Lindgaard指数明显大于无症状组(P<0.01或P<0.05)。结论TCCS检测外伤性蛛网膜下腔出血患者的大脑中动脉VMCA和Lindgaard指数可以很好地了解大脑中动脉痉挛程度。     

Possible overlap between reversible cerebral vasoconstriction syndrome and symptomatic vasospasm after aneurysmal subarachnoid hemorrhage

A 34-year-old woman with a previous history of severe headache (“thunderclap”) was admitted with a diagnosis of aneurysmal subarachnoid hemorrhage (SAH). The patient developed symptomatic vasospasm on day 5 that resolved rapidly after having increased arterial blood pressure. She experienced also short-lasting excruciating headache. On day 12, while velocities had normalised, as revealed by transcranial Doppler (TCD), for more than 48 h, she developed aphasia and right hemiplegia associated with diffuse segmental vasospasm on the left middle cerebral artery. Intra-arterial infusion of vasodilatory agents was required. Recurrence of symptomatic vasospasm was noted on day 25, with a great number of territories involved as shown in the cerebral angiogram. A second intra-arterial treatment was needed. The patient complained of multiple episodes of extremely severe headache (“thunderclap”), with also transient dysarthria and hemiparesia on day 30. She was discharged on day 38 after full recovery. The clinical and TCD/radiological findings were consistent with a reversible cerebral vasoconstriction syndrome overlapping SAH related symptomatic vasospasm.     

28例蛛网膜下腔出血患者经颅多普勒超声检查

目的:应用经颅多普勒超声(TCD)动态观察蛛网膜下腔出血(SAH)后血流变化情况,预测血管痉挛(VSP)的发生.方法:本文应用TCD动态观察28例SAH患者病后4周内大脑中动脉血流速度(FV)变化,与脑CT显示出血量进行比较,同时观察临床体征的变化.结果:SAH后FV异常率为75%(21/28),VSP的发生率为35.7%(10/28),其中60%(6/10)发生于病后8-12天,持续6～18天;两侧FV明显高于对侧(P<0.01);3例出现症状性VSP患者均为出血量较大者,并于症状出现前1～2天FV每天增加30cm/s以上,平均FV为200cm/s.结论:通过TCD检查可以预测SAH后VSP的发生,其发生率为35.7%,多于病后1～2周内发生; 出血量越多,VSP发生可能性越大;FV大于200cm/s或每大增加超过30cm/s.有发生症状性VSP的倾向.     

自发性蛛网膜下腔出血后低钠血症的临床研究

目的 研究自发性蛛网膜下腔出血(SAH)患者低钠血症的发生情况.方法 对36例蛛网膜下腔出血患者按出血量、病情轻重、脑血管痉挛的情况及血钠水平进行动态观察.用TCD检测大脑中动脉血流速度(VMCA).结果 脑血管痉挛的患者其血钠水平明显降低,有明显的临床意义.结论 低钠血症是蛛网膜下腔出血常见的并发症,且是反映蛛网膜下腔出血病情程度的一个重要指标.应严密监测并及时明确病因、尽早治疗,以改善病情及预后.     

法舒地尔防治动脉瘤介入栓塞术后脑血管痉挛的疗效观察

【目的】探讨盐酸法舒地尔防治颅内动脉瘤破裂蛛网膜下腔出血（SAH）介入栓塞术后脑血管痉挛（CVS）的效果。【方法】将60例脑动脉瘤破裂SAH介入栓塞术后患者随机分为治疗组和对照组各30例,治疗组术后给予法舒地尔30mg静脉滴注q8h,疗程14d,每次静脉滴注时间为30min;对照组30例,术后采用尼莫地平,1mg／h,静脉泵入,疗程14d,比较两组的Glasgow评分,头部CT及经颅多普勒（TCD）观察大脑中动脉（MCA）血流速度的变化。【结果】法舒地尔与尼莫地平均可迅速促进疾病的好转;对CT检查所见脑内低密度灶,法舒地尔与尼莫地平均可使其改善;法舒地尔与尼莫地平扩张痉挛脑动脉的作用较好,两者无显著性差异（P〉0．05）。【结论】法舒地尔与尼莫地平均是预防和治疗动脉瘤破裂SAH介入栓塞术后CVS安全有效的药物。