Ruptured superior cerebellar artery aneurysm in a child with bilateral fibromuscular hyperplasia of the renal arteries: case report and review of the literature

The authors report the case of a pediatric patient with bilateral fibromuscular hyperplasia (FMH) of the renal arteries who sustained a subarachnoid hemorrhage (SAH) caused by the rupture of a superior cerebellar artery aneurysm. The aneurysm was successfully treated with microsurgical clip occlusion. The association between renal artery FMH and aneurysmal SAH is extremely rare and incompletely understood. There are six previously published cases in the English literature; only one case involved direct aneurysm treatment and none involved the posterior circulation. In addition to presenting this case, the authors discuss the complexities involved in treating these patients from a technical and conceptual standpoint.

Cerebral Vasospasm After Subarachnoid Hemorrhage

Cerebral vasospasm is a significant problem after subarachnoid hemorrhage, with often devastating consequences. Its pathogenesis remains poorly understood despite extensive research. Owing to the lack of a clear etiology, medical treatment is still largely limited to triple-H therapy and calcium channel blockers, although newer treatments such as percutaneous transluminal angioplasty and papaverine infusion are becoming more common. Clinical symptoms are often first noted by the registered nurse, who must then alert the physician to the need for diagnostic workup and therapy. Caring for patients after subarachnoid hemorrhage requires awareness of the potential for the development of vasospasm, and knowledge of the steps necessary to ensure its timely diagnosis and treatment. This article will review the current body of knowledge as it pertains to vasospasm and outline the direction of ongoing research.

Assessment of changes in cerebral circulation time due to vasospasm in a specific arterial territory: effect of angioplasty

This study demonstrates that in experienced hands, intracranial angioplasty is a feasible and safe option in a selected group of patients with severe (>50% stenosis) symptomatic vasospasm following subarachnoid hemorrhage. Cerebral circulation time is a surrogate parameter closely linked to cerebral perfusion. The study presented shows that not only stenosis but also changes in circulation time are obtained by angioplasty. Twenty angioplasties of one or two vessel segments were performed over 2 years in 18 consecutive patients with posthemorrhagic vasospasm fulfilling criteria for invasive treatment. In all patients, degree of stenosis and circulation time could be reduced by angioplasty. Clinical results were ranked according to Glasgow Outcome Scale. Imaging after 15/20 angioplasties showed no additional infarction. In 4/20 cases, CT showed demarcation of infarction after angioplasty. In 1/20 cases of posterior circulation angioplasty, CT is not sensitive enough to exclude smaller infarctions. Imaging and clinical outcome reveal a definite benefit.

Trends in Surgical and Management Outcomes in Patients with Aneurysmal Subarachnoid Hemorrhage in Izumo City, Japan, between 1980–1989 and 1990–1998

BACKGROUND AND PURPOSE

The purpose of this community-based study was to evaluate temporal changes in surgical and management outcomes in patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

The subjects were 358 patients with aneurysmal SAH who were treated during the 19-year period from 1980 to 1998 in Izumo City, Japan. We compared data during the 9-year period 1990-1998 (period B; 188 patients) with those during the 10-year period 1980-1989 (period A; 170 patients).

RESULTS

The proportion of patients 80 years of age or older or those with World Federation of Neurosurgical Societies grade V increased significantly (period A, 5 and 25%; period B, 18 and 35%, respectively). The operability rate did not change for patients 69 years of age or younger, whereas it increased significantly for those 70-79 years of age (period A, 48%; period B, 72%). The 6-month and 2-year case fatality rates in surgically treated patients decreased significantly (period A, 12 and 20%; period B, 2 and 8%, respectively), whereas they were virtually unchanged for overall management (period A, 41 and 46%; period B, 38 and 42%, respectively). In patients who underwent surgery, the incidence of permanent symptomatic vasospasm decreased from 21% during period A to 11% during period B, and there was no death from vasospasm in the later period. However, no significant difference was found in the functional outcome between the two periods, regardless of whether surgery was performed. The most important determinants of 6-month and 2-year survival rates were grade on admission, rebleeding and the site of the ruptured aneurysms. Age was also a significant predictor of the 6-month case fatality rate.

CONCLUSIONS

For patients with SAH who underwent surgery, there were trends towards decreases in the case fatality rate and in the incidence of permanent symptomatic vasospasm. Nevertheless, the overall management outcome was still unsatisfactory, mainly because of increasing numbers of very elderly and/or high-risk patients. .

Tissue at risk concept for endovascular treatment of severe vasospasm after aneurysmal subarachnoid haemorrhage

OBJECTIVE

To report a case of severe vasospasm after subarachnoid haemorrhage (SAH) where "tissue at risk" was identified by magnetic resonance imaging (MRI), and to demonstrate the haemodynamic consequences with either resolution of the perfusion-diffusion mismatch by balloon angioplasty or evolution of an infarct.

METHODS

A 45 year old women with SAH underwent surgical treatment of a ruptured middle cerebral artery (MCA) aneurysm. On day 3 she became obtunded and developed a right hemiparesis. Diffusion weighted (DWI) and perfusion weighted (PWI) imaging were done before and after transluminal balloon angioplasty (TBA) of multifocal proximal vasospasm.

RESULTS

The initial MRI revealed no DWI lesion but PWI showed a severe perfusion deficit of 6.7 to 16.4 seconds in the complete left MCA territory. Digital subtraction angiography confirmed severe segmental narrowing of left C1 and M1. The spastic segments were successfully dilated by TBA. Follow up MRI showed that the PWI-DWI mismatch resolved in the anterior and middle MCA territory with no tissue infarction, whereas in the terminal dorsal MCA territory a severe mismatch remained and cerebral infarction evolved.

CONCLUSIONS

PWI/DWI can identify tissue at risk for infarction in severe vasospasm following SAH. This may allow selection of patients for angioplasty and the monitoring of treatment effects.

Treatment of cerebral vasospasm after subarachnoid hemorrhage--a review

Delayed cerebral ischemia as a result of cerebral vasospasm is the most common cause of death and disability after aneurysmal subarachnoid hemorrhage (SAH). It leads to death or permanent neurologic deficits in over 17-40% of SAH patients. The initial and main symptom of cerebral vasospasm is diffuse headache and may be accompanied with a slight increase in discomfort from neck stiffness and fever. The clinical diagnosis of cerebral vasospasm is made when the patient experiences an altered level of consciousness or a new focal neurologic deficit. There has been a great progress in identifying the patients at risk, putative mechanisms, and possible treatment options for cerebral vasospasm. However, the problem is by no means solved, mainly due to a limited understanding of the pathologic mechanisms of this complex disease. The iatrogenic factors that can increase the risk of cerebral vasospasm include prolongation of the subarachnoid clot by antifibrinolytic drugs, hypotension, inappropriate treatment of hyponatremia, hypovolemia, hyperthermia and increased intracranial pressure. Nimodipine has been shown to improve neurologic outcome and decrease the incidence of cerebral vasospasm. Triple H therapy is a treatment designed to augment cerebral blood flow for patient with cerebral vasospasm. Hypervolemic hypertension is induced with intravenous volume expansion with crystalloid or colloid to increase cardiac output and raise blood pressure. However, small randomized trials showed no clear benefit. Recently, balloon and chemical angioplasty with superselective intra-arterial injection of vasodilators has emerged as the primary intervention for treating medically refractory ischemia from cerebral vasospasm and in many centers is being used as a first-line treatment or even prophylactically. In addition, promising new treatments for cerebral vasospasm or its ischemic complications include magnesium sulfate, fasudil hydrochloride, tirilazad mesylate, erythropoietin, and induced hypothermia; however, all still need further clinical trials. Newly recognized mediators of cerebral vasospasm after SAH include endothelium-derived mediators, vascular smooth-muscle-derived mediators, proinflammatory mediators involved in blood-brain barrier disruption, cytokines and adhesion molecules, stress-induced gene activation, and platelet-derived growth factors. Moreover, observations in the laboratory have, in many circumstances, matched those of reported small series. Larger, prospective, randomized trials are needed to verify several hypotheses of molecular pathophysiology and clinical treatment regimens.

Predictors of outcome after endovascular treatment of cerebral vasospasm

BACKGROUND AND PURPOSE

Angioplasty and intra-arterial papaverine are promising treatments for severe symptomatic vasospasm after subarachnoid hemorrhage (SAH), but there is little information on the clinical factors that predict treatment outcome. We sought to determine variables for predicting functional outcome in this setting.

METHODS

We reviewed 81 consecutive patients with symptomatic cerebral vasospasm from aneurysmal SAH treated with percutaneous balloon angioplasty or selective intra-arterial papaverine infusion between 1990 and 2000 (105 procedures). Logistic regression analysis was used to assess the effect of various clinical and angiographic factors on outcome.

RESULTS

Mean patient age was 54 years (range, 29-88 years). Twenty-nine patients (36%) presented with poor-grade (World Federation of Neurologic Surgeons [WFNS] grade IV or V) SAH. Clinical deficits were global in 55 patients (70%), and angiographic vasospasm was diffuse in 53 (65%). Endovascular treatment consisted of transluminal angioplasty alone (18 procedures, 17%), intra-arterial papaverine infusion (65 procedures, 62%), or both (22 procedures, 21%). Unequivocal arterial dilatation was achieved in all but two patients, and major complications occurred in 2% of the procedures. Ten patients (12%) died in the hospital, and 36 (44%) recovered poorly. Permanent deficits attributable to cerebral vasospasm were present in 37 patients (52% of survivors). On multivariate logistic regression analysis, advanced age and poor WFNS grade at presentation were predictive of poor clinical outcome.

CONCLUSION

Advanced age and poor clinical status at the time of SAH onset are predictive of poor clinical outcome despite endovascular treatment with angioplasty or intra-arterial papaverine in patients with symptomatic vasospasm.

Vasospasm after aneurysmal subarachnoid hemorrhage

Despite every effort, 13% of patients with SAH still die or are permanently disabled as a consequence of vasospasm. Optimal outcome after aneurysmal SAH depends on careful assessment and management of patients throughout the course of hospitalization. Critical care nurses play a crucial role in this process. Efforts continue to understand the cascade of events that lead to cerebral vasospasm and to develop more effective treatments. Many therapies, both traditional and new, are being investigated to reduce the incidence of symptomatic vasospasm and improve the lives of patients who experience this devastating condition.

Effect of Clipping, Craniotomy, or Intravascular Coiling on Cerebral Vasospasm and Patient Outcome after Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE:

Although several recent studies have suggested that the incidence of vasospasm after aneurysmal subarachnoid hemorrhage is lower in patients undergoing aneurysmal coiling as compared with clipping, other studies have had conflicting results. We reviewed our experience over 8 years and assessed whether clipping, craniotomy, or coiling affects patient outcomes or the risk for vasospasm.

METHODS:

We included 515 patients with aneurysmal subarachnoid hemorrhage, identified prospectively from November 2000 to February 2003 (243 patients) and retrospectively from November 1995 to October 2000 (272 patients), by using International Classification of Diseases, 9th Revision, codes for subarachnoid hemorrhage. We classified patients as follows: clipping (413 patients), coiling (79 patients), and craniotomy (436 patients, including all 413 patients who underwent clipping plus 23 who underwent coiling as well as craniotomy for various reasons). We studied four outcome measures: total vasospasm, symptomatic vasospasm, poor outcome (modified Rankin score 3–6), and in-hospital mortality. To assess the risk of total vasospasm and symptomatic vasospasm, we performed multivariate regression analyses adjusting for age, Fisher grade, Hunt and Hess grade, aneurysm location (anterior versus posterior circulation), and aneurysm treatment modality. To assess the risk for poor outcome and in-hospital mortality, we adjusted for all the above variables as well as for total and symptomatic vasospasm.

RESULTS:

In the clipping group there was 63% total vasospasm and 28% symptomatic vasospasm; in the coiling group there was 54% total vasospasm and 33% symptomatic vasospasm; and in the craniotomy group there was 64% total vasospasm and 28% symptomatic vasospasm. In the multivariate analysis, age <50 years (P = 0.0099) and Fisher Grade 3 (P < 0.00001) predicted total vasospasm, and Fisher Grade 3 (P < 0.000001) and Hunt and Hess Grade IV or V (P = 0.018) predicted symptomatic vasospasm. Predictors of poor outcome were age ≥50 years (P < 0.0001), Fisher Grade 3 (P = 0.0072), Hunt and Hess Grade IV or V (P < 0.00001), symptomatic vasospasm (P < 0.0001), and coiling (P = 0.0314 versus clipping and P = 0.045 versus craniotomy). Predictors of in-hospital mortality were age ≥ 50 years (P = 0.0030), Hunt and Hess Grade IV or V (P = 0.0001), symptomatic vasospasm (P < 0.00001), and coiling (P = 0.008 versus clipping and P = 0.0013 versus craniotomy). There was no significant difference in total vasospasm or symptomatic vasospasm when patients who underwent clipping or craniotomy were compared with patients who underwent coiling. In patients with Hunt and Hess Grade I to III (“good grade”), clipping and craniotomy were associated with better outcome and less in-hospital mortality, but there was no difference in total vasospasm or symptomatic vasospasm versus coiling. In patients with Hunt and Hess Grade IV or V (“poor grade”), there was no difference in any outcome measure among the treatment groups.

CONCLUSION:

In a single-center, retrospective, nonrandomized study, performance of clipping and/or craniotomy had significantly better outcome and lower mortality at discharge than coiling in good-grade patients but had no effect on total vasospasm or symptomatic vasospasm in good- or poor-grade patients.

Intentional partial coil occlusion followed by delayed clip application to wide-necked middle cerebral artery aneurysms in patients presenting with severe vasospasm. Report of two cases

The treatment of ruptured cerebral aneurysms in patients presenting with vasospasm remains a particular challenge. The authors treated two patients harboring Hunt and Hess Grade 1 subarachnoid hemorrhages from middle cerebral artery (MCA) aneurysms associated with severe local angiographically demonstrated yet asymptomatic vasospasm on presentation. Because both aneurysms had wide necks and were located at the MCA bifurcation, they were believed to be anatomically suitable for microsurgical clip application. Severe M, vasospasm was believed to be a relative contraindication to open surgery, however. An intentionally staged endovascular and microsurgical treatment strategy was planned in each patient. Partial coil occlusion of the aneurysmal dome was performed to prevent the lesion from rebleeding and was followed by balloon angioplasty of the spastic vessel. Early treatment of the severe spasm appeared to prevent significant delayed neurological ischemic deficit. Following resolution of the vasospasm, definitive clipping of the aneurysms was performed on Day 13 post embolization. One patient had a good clinical recovery and was discharged without neurological deficit. The other patient's hospital course was complicated by the occurrence of a postoperative posterior temporal infarct requiring partial temporal lobectomy, although she eventually had a good recovery with only a small visual field deficit. Based on data obtained in these two patients, one can infer that ruptured wide-necked MCA aneurysms associated with severe local vasospasm may best be treated using a staged combined treatment plan. Delayed clip application might be performed more safely 4 to 6 weeks postocclusion, or later, than at 2 weeks.

[Differences in outcome in patients with poor grade subarachnoid hemorrhage (WFNS grade IV and V): according to the perioperative management against vasospasm]

Cerebral vasospasm remains a leading cause of morbidity and increasing mortality rates following aneurysmal subarachnoid hemorrhage (SAH). The rate of vasospasm and the outcome (Glasgow Outcome Scale; GOS) especially in poor WFNS grade were retrospectively analyzed over a 6-year period. Patients were divided into three different groups. The first group (pre-group) consisted of 43 patients (grade IV: 31, grade V: 12), who were admitted between 1996 and 1998. When vasospasm occurred, they were mainly treated by papaverine (PPV) and percutaneous transluminal angioplasty (PTA). In the second group (mil-cis group), for the prevention of vasospasm, cisternal irrigation therapy with milrinone was applied in 24 patients (grade IV: 13, grade V: 11), who were admitted in the period between 1999 and 2001. The third group, (w/o mil-cis group), consisted of 30 patients (grade IV: 15, grade V: 15), in whom cisternal irrigation therapy was not able to be carried out. In grade IV, vasospasm was observed in 66% of the patients the first group, 50% in the w/o mil-cis group and significantly less in the mil-cis group (15%, p<0.024). In grade V, the rate of vasospasm was also lower in the mil-cis group but no statistical significance was revealed. Although the rate of favorable outcome in GOS was highest and the rate of death was least in the mil-cis group in both grade IV and V, only the trend was observed. Many factors should be considered, Cisternal irrigation therapy with milrinone reduced the occurrence of vasospasm. However, outcome was not improved because of the initial poor clinical condition.

Endovascular management of poor-grade aneurysmal subarachnoid hemorrhage in the geriatric population

BACKGROUND AND PURPOSE

The incidence of poor-grade (Hunt and Hess grade IV and V) subarachnoid hemorrhage (SAH) is higher in elderly patients (>70 years) than in younger groups. The aim of this retrospective study was to analyze the outcome of these poor grade elderly patients after endovascular treatment.

METHODS

We retrospectively reviewed the clinical records of 27 patients older than 70 years who underwent endovascular treatment for aneurysmal SAH between January 1996 and July 2002. Thirteen patients with SAH and a poor Hunt and Hess grade at initial presentation had been treated by endovascular means. Their outcomes were assessed by the using the Glasgow Outcome Scale (GOS).

RESULTS

Two patients (15%) had a good outcome according to the GOS. Three patients (23%) were moderately disabled, two (15%) were severely disabled at the time of discharge from the hospital, and six (47%) died. Five patients (38%) developed clinical vasospasm and underwent balloon angioplasty. Three procedure-related deaths occurred (23%).

CONCLUSION

Endovascular treatment has modified the management of poor-grade SAH in elderly patients, most of whom are high-risk surgical candidates. Endovascular treatment can be administered early after the initial ictus, reducing the risk of rebleeding and providing an option to pursue aggressive triple-H therapy. Symptomatic vasospasm can also be treated by endovascular means in the initial setting.

The pharmacologic treatment of vasospasm after subarachnoid hemorrhage: a case study

The patient with a diagnosis of SAH and subsequent vasospasm presents many nursing challenges and requires complex pharmacologic management. By paying careful attention to the therapeutic and potential side effects of the medications prescribed, the nurse can be instrumental in the patient's recovery.

Intracranial heme metabolism and cerebral vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The goal of this prospective study was to clarify the potential role of an inducible heme-metabolizing enzyme, heme oxygenase (HO)-1, and an inducible iron-detoxifying protein, ferritin, in cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH).

METHODS

The authors measured the levels of bilirubin and iron, which are by-products of HO-1, and the ferritin levels in the cerebrospinal fluid in 39 consecutive patients with aneurysmal SAH of Fisher computed tomography group III, and determined the relationship between these by-products of HO-1 or ferritin and vasospasm.

RESULTS

Fourteen of 39 patients (35.9%) developed asymptomatic vasospasm, while 6 patients (15.4%) developed symptomatic vasospasm. The levels of ferritin, bilirubin, and iron were all significantly elevated after SAH. The levels of ferritin and bilirubin were significantly higher in patients with no vasospasm than in patients with asymptomatic and symptomatic vasospasm on days 5 through 7 (P<0.05, respectively) and on days 11 through 14 (P<0.025 in bilirubin) after SAH. However, no significant difference was observed in the iron levels between these patient groups.

CONCLUSIONS

This is the first study to show that higher levels of bilirubin and ferritin in the cerebrospinal fluid after SAH were associated with no vasospasm in clinical settings. These findings support the concept that the induction of HO-1 and ferritin may be an intrinsic regulatory mechanism that acts against cerebral vasospasm.

Effect on Cerebral Vasospasm of Coil Embolization Followed by Microcatheter Intrathecal Urokinase Infusion Into the Cisterna Magna

Background and Purpose— Vasospasm remains the leading cause of death and permanent neurological disability in patients with aneurysmal subarachnoid hemorrhage (SAH). The objective of our prospective randomized trial of coil embolization followed by intrathecal urokinase infusion into the cisterna magna (ITUKI therapy) was to test its effectiveness in preventing or alleviating the severity of ischemic neurological deficits caused by vasospasm.

Methods— We enrolled 110 patients with ruptured intracranial aneurysms eligible for coil embolization and randomly assigned them to embolization with (n=57) or without (n=53) ITUKI therapy performed within 24 hours of aneurysmal SAH. The incidence of symptomatic vasospasms and the clinical outcomes, based on the Glasgow Outcome Scale, 6 months after SAH onset were assessed.

Results— There were no side effects or adverse reactions attributable to ITUKI therapy. Symptomatic vasospasm occurred in 5 patients (8.8%) with and 16 (30.2%) without ITUKI therapy; the difference was significant ( P =0.012). Although the mortality rate did not differ between the groups, patients with ITUKI therapy had significantly better outcomes than those without ( P =0.036).

Conclusions— Our results demonstrate that ITUKI therapy significantly reduced the occurrence of symptomatic vasospasm. Although it did not completely prevent vasospasms, ITUKI therapy resulted in a lower rate of permanent neurological deficits.

Increases in Cardiac Output Can Reverse Flow Deficits from Vasospasm Independent of Blood Pressure: A Study Using Xenon Computed Tomographic Measurement of Cerebral Blood Flow

INTRODUCTION

Vasospasm after subarachnoid hemorrhage remains a management challenge. The accepted treatment involves hypertensive, hypervolemic, hemodilution therapy. However, there is variation in the application of this treatment. Most authors increase mean arterial pressure (MAP), which can be associated with significant morbidity. Others increase cardiac output (CO). In this study, we examined the relationship between volume status, CO, and MAP and cerebral blood flow (CBF) in the setting of vasospasm.

METHODS

A xenon blood flow tomography-based system was used to quantitate CBF. Sixteen patients with vasospasm after subarachnoid hemorrhage were treated with hypervolemia, phenylephrine to increase MAP, or dobutamine to increase CO. Direct CBF measurements were obtained before and after treatment. A strength of this study is that only one variable (central venous pressure, MAP, or CO) was manipulated in each patient, and the effect of this change was measured immediately.

RESULTS

With phenylephrine, mean MAP increased from 102.4 to 132.1 mm Hg. In regions of diminished CBF due to vasospasm, mean CBF increased from 19.2 to 33.7 ml/100 g/min. Similarly, dobutamine increased the cardiac index from a mean of 4.1 to 6.0 L/min/m2 and slightly decreased MAP. CBF increased from a mean of 24.8 to 35.4 ml/100 g/min. Both were statistically significant changes. With hypervolemia, the average central venous pressure increased from a mean of 5.4 to 7.3 cm H2O; no changes in mean CBF were noted.

CONCLUSION

This article reports the first human study that shows with direct measurements the independent influence of CO in the setting of vasospasm. Increases in CO without changes in MAP can elevate CBF. This finding has immediate clinical application because CO manipulation is much safer than increasing MAP. Because both interventions were equally efficacious, our protocol has been changed to augment CO as a first measure. Induced hypertension is reserved for patients in whom this initial treatment fails.

Triple-H therapy in the management of aneurysmal subarachnoid haemorrhage

Cerebral vasospasm is a recognised but poorly understood complication for many patients who have aneurysmal subarachnoid haemorrhage and can lead to delayed ischaemic neurological deficit (stroke). Morbidity and mortality rates for vasospasm are high despite improvements in management. Since the middle of the 1970s, much has been written about the treatment of cerebral vasospasm. Hypervolaemia, hypertension, and haemodilution (triple-H) therapy in an intensive-care setting has been shown in some studies to improve outcome and is an accepted means of treatment, although a randomised controlled trial has never been undertaken. In this review, the rationale for this approach will be discussed, alongside new thoughts and future prospects for the management of this complex disorder.

Gene therapy for cerebral vascular disease: update 2003

Gene therapy is a promising strategy for cerebrovascular diseases. Several genes that encode vasoactive products have been transferred via cerebrospinal fluid for the prevention of vasospasm after subarachnoid hemorrhage. Transfer of neuroprotective genes, including targeting of proinflammatory mediators, is a current strategy of gene therapy for ischemic stroke. Stimulation of growth of collateral vessels, stabilization of atherosclerotic plaques, inhibition of thrombosis, and prevention of restenosis are important objectives of gene therapy for coronary and limb arteries, but application of these approaches to carotid and intracranial arteries has received little attention. Several fundamental advances, including development of safer vectors, are needed before gene therapy achieves an important role in the treatment of cerebrovascular disease and stroke.

Role of hypothermia in the management of severe cases of subarachnoid hemorrhage

Mild hypothermia is thought to have a brain protective effect to pathophysiological conditions, which are caused by severe brain damage including brain injury and cerebral stroke. In this paper, general aspects of this treatment as history, pathophysiological effect, and problems are summarized. Also, the clinical effects of hypothermic therapy for a subarachnoid hemorrhage are reviewed. Main targets of the therapy for this disease are severe primary brain damage caused by the attack itself and secondary ischemic brain damage after delayed vasospasm. But even now, there are no fully established data about the effect of hypothermia at such conditions after subarachnoid hemorrhage. The results of our study of cerebral blood flow and cerebral oxygen metabolism using positron emission tomography are presented to show the physiological effect of hypothermia on human brain after severe brain damage caused by subarachnoid hemorrhage. In conclusion, effect of hypothermia on subarachnoid hemorrhage is not confirmed yet and reported data is limited, so that additional studies, especially controlled studies, would be recommended.

Transluminal balloon angioplasty improves brain tissue oxygenation and metabolism in severe vasospasm after aneurysmal subarachnoid hemorrhage: case report

OBJECTIVE AND IMPORTANCE

The effect of transluminal balloon angioplasty on cerebral biochemical monitoring during treatment of severe cerebral vasospasm after subarachnoid hemorrhage (SAH) was investigated.

CLINICAL PRESENTATION

In a 36-year-old man, an anterior communicating artery aneurysm caused an SAH (Hunt and Hess Grade IV, Fisher Grade III). After clipping, intraparenchymal monitoring (intracranial pressure, brain tissue oxygen tension [P(ti)O(2)], and microdialysis sampling of extracellular glucose, lactate, pyruvate, and glutamate) was initiated. Flow velocities obtained by transcranial Doppler sonography increased in the internal carotid artery (ICA)/middle cerebral artery bilaterally.

INTERVENTION

After a decrease of P(ti)O(2) to less than 2 mm Hg and an increase of the lactate-to-pyruvate ratio to 44 in the territorial region of the left ICA, angiography demonstrated a 70 to 80% stenosis of the left ICA, which was dilated by a temporary occlusion balloon. This maneuver normalized the ICA diameter, P(ti)O(2) increased immediately from 1.5 to 40 mm Hg, the lactate-to-pyruvate ratio decreased from 44 to 30, and extracellular glucose increased from 0.4 to 0.9 mmol/L. No major changes in glutamate or intracranial pressure were seen. In the clinical follow-up, the patient showed a good recovery 6 months after SAH.

CONCLUSION

Transluminal balloon angioplasty led to a continuous and effective resolution of cerebral vasospasm observed by sustained, improved cerebral biochemical parameters. Both P(ti)O(2) and lactate-to-pyruvate ratio might provide an early diagnosis of severe cerebral vasospasm after SAH and continuous surveillance of threatened tissue regions after transluminal balloon angioplasty.

Cervical sympathetic block to reverse delayed ischemic neurological deficits after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The purpose of the present study was to evaluate the feasibility and safety of a locoregional cervical sympathetic block to improve cerebral perfusion in patients suffering from cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

METHODS

Nine consecutive patients with symptoms of delayed ischemic deficits, induced by angiographically confirmed cerebral vasospasm, were treated with the injection of locoregional anesthesia to block the ascending cervical sympathetic chain at the level of the superior cervical ganglion. Neurological status was recorded before and after the procedure, and cerebral angiography was performed before and after the procedure.

RESULTS

No complications occurred in this short series. The procedure appeared to be simple and safe. Horner's signs appeared within 12+/-0.1 minutes and lasted for an average of 6.3+/-4 hours. In all patients, improved cerebral perfusion was detected at the confirmatory angiography but without change in vessel caliber. One patient died of the complications of the initial hemorrhage, and 2 died of the consequences of the severe vasospasm despite maximal medical treatment. In all the other cases, the neurological status promptly returned to normal within 48 hours after the locoregional treatment.

CONCLUSIONS

Patients with mild to moderate symptoms seem to benefit greatly from transient ipsilateral cervical sympathetic block. This simple technique may be helpful when used as an adjunct to the standard therapy to improve cerebral perfusion.

Aneurysmal subarachnoid hemorrhage in patients with Hunt and Hess grade 4 or 5: treatment using the Guglielmi detachable coil system

BACKGROUND AND PURPOSE

Patients in poor clinical condition (Hunt and Hess grade 4 or 5) after subarachnoid hemorrhage (SAH) have historically fared poorly and many often were excluded from aggressive treatment. Early aggressive surgical treatment of SAH can produce good-quality survival for a higher percentage of patients than previously reported. We assessed the outcome of patients with Hunt and Hess grade 4 or 5 who were treated with Guglielmi detachable coil (GDC) embolization.

METHODS

We retrospectively evaluated the records of 27 consecutive grade 4 and 5 patients with 29 aneurysms treated within 72 hours of SAH by using GDCs. Percentage aneurysm occlusion after embolization, perioperative complications, and symptoms of vasospasm were evaluated. Outcome was assessed with the Glasgow Outcome Scale.

RESULTS

Sixteen patients (59%) were grade 4, and 11 (41%) were grade 5. Eighteen (67%) had one aneurysm, six (22%) had two aneurysms, and three (11%) had three aneurysms. Twenty-nine aneurysms were treated. Fourteen (48%) were completely occluded, and four (14%) were nearly completely occluded (>/=95% occlusion) at embolization. Eleven aneurysms (38%) had partial coiling (<95% occlusion). In the 27 patients, one technical (4%) and one clinical (4%) complication occurred at embolization. No rehemorrhage occurred in any patients (follow-up, 6-44 months; mean, 23 months). Twenty-five (92%) had vasospasm, and seven required endovascular treatment because of worsening clinical status. Sixteen patients (59%) died within 30 days of SAH. Eight patients (30%) had a good clinical outcome at a mean follow-up of 23 months.

CONCLUSION

Patients with Hunt and Hess grade 4 or 5 after SAH can undergo successful coil embolization of the aneurysms despite their poor medical condition and a high frequency of vasospasm at the time of treatment. Morbidity and mortality rates with this disease are still high. These findings compare favorably with those published in surgical series for aggressively treated patients with Hunt and Hess grade 4 or 5.

Cerebral vasospasm after subarachnoid hemorrhage

PURPOSE OF REVIEW

To summarize new pathophysiologic insights and recent advances in the diagnosis and treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

RECENT FINDINGS

Important, newly recognized mediators of cerebral arterial spasm after subarachnoid hemorrhage include superoxide free radicals, ferrous hemoglobin (which acts as a nitric oxide scavenger), endothelins, protein kinase C, and rho kinase. Microvascular dysfunction and autoregulatory failure also has been an area of increasing research focus in recent years. New diagnostic modalities include measures of cerebral blood flow such as single-photon emission computed tomography and perfusion computed tomography, magnetic resonance imaging, intracranial brain oxygen tension probes, and jugular venous oxygen saturation monitors. Proton magnetic resonance spectroscopy and microdialysis can detect tissue biochemical abnormalities, but these techniques have not found their way into routine clinical practice as of yet. In addition to nimodipine and hypertensive hypervolemic therapy, promising new treatments for vasospasm or its ischemic complications include magnesium sulfate, fasudil hydrochloride, tirilazad mesylate, erythropoietin, and induced hypothermia. Balloon angioplasty has emerged as the primary weapon for treating medically refractory ischemia from vasospasm and in many centers is being used as a first-line treatment or even prophylactically.

SUMMARY

The neurointensive care management of vasospasm after subarachnoid hemorrhage has evolved significantly over the past 10 years, with many new diagnostic modalities and promising treatments now available. Clinical trials are needed to evaluate the efficacy of these new techniques and to further define the optimal management of this often devastating complication.

The use of mild hypothermia for patients with severe vasospasm: a preliminary report

The purpose of this study was to determine the effect of mild hypothermia on cerebral ischaemia due to severe vasospasm, which was refractory to medical and intravascular treatments and to assess the brain protection of this treatment in patients who underwent delayed aneurysm clipping after presenting with ischaemic neurological deficits. Mild hypothermia (32-34 degrees C of brain temperature) was employed in two groups: (1) Patients (Hunt and Kosnik grades I to II) who showed progressive neurological deficits due to vasospasm and did not respond to conventional therapy (Group 1) and (2) Patients who received delayed aneurysm clipping after presenting with ischaemic neurological deficits due to vasospasm (Group 2). Seven of 8 patients in both Groups showed a favorable outcome with mild hypothermia (good recovery in 5 and moderate disability in two patients). Mild hypothermia is considered to be effective on critical cerebral ischaemia due to vasospasm even after failure to response the conventional therapies and to provide brain protection in delayed aneurysm clipping.

Papaverine angioplasty to treat cerebral vasospasm following traumatic subarachnoid haemorrhage

The management of vasospasm associated with traumatic subarachnoid haemorrhage presents many challenges. We present a 20-year-old male admitted after sustaining a closed head injury complicated by a Fisher grade III traumatic subarachnoid haemorrhage. Despite treatment with intravenous nimodipine he developed a delayed ischaemic neurological deficit due to cerebral arterial vasospasm. The vasospasm was successfully managed with serial papaverine angioplasty.

Combined endovascular treatment for both intracranial aneurysm and symptomatic vasospasm

BACKGROUND AND PURPOSE

The best strategy for treatment of subarachnoid hemorrhage due to ruptured cerebral aneurysm is obliteration of the aneurysm as soon as possible. Early surgery is desirable if the patient does not develop severe vasospasm or is clinically stable. However, if the patient has already developed severe vasospasm on admission, surgery may carry the risk of increasing the severity. We evaluated the safety and effectiveness of combined Guglielmi detachable coil (GDC) embolization and angioplasty in a single session for the treatment of ruptured aneurysms associated with symptomatic vasospasm.

METHODS

From January 1992 to January 2001, 12 consecutive patients with ruptured aneurysms associated with symptomatic vasospasm were treated. Patients were classified as Hunt and Hess grade 2 (n = 1), 3 (n = 6), 4 (n = 4), or 5 (n = 1) and Fisher CT group 2 (n = 1), 3 (n = 10), or 4 (n = 1). They underwent GDC aneurysm occlusion and balloon angioplasty (n = 6), intraarterial papaverine infusion (n = 2), or both (n = 4) in a single session. In nine patients, aneurysm coil occlusion was performed first.

RESULTS

Complete GDC occlusion was achieved in eight patients, a small neck remnant persisted in three, and embolization was incomplete in one patient. In all patients, angiographic improvement of vasospasm was obtained. In one patient, a thromboembolic complication occurred and was treated with urokinase. Clinical outcomes at discharge were good recovery in six, moderate disability in two, severe disability in three, or death in one.

CONCLUSION

Endovascular treatment can be the first therapeutic option for ruptured aneurysms associated with severe vasospasm on admission. It offers some advantages over surgery in this setting, but these are balanced by the risk of thromboembolism.

Critical care issues in stroke and subarachnoid hemorrhage

The outcomes of devastating neurological emergencies such as stroke and subarachnoid hemorrhage may be measurably improved by timely treatment in a neurointensive care unit (NICU). Optimal care requires a multidisciplinary approach, with attention to a wide range of treatment issues. This review examines the key therapeutic concerns in the NICU management of acute ischemic and hemorrhagic stroke and subarachnoid hemorrhage, including mechanical ventilation, blood pressure management, cardiac monitoring, intracranial pressure assessment, vasospasm, seizures, sedation, fluids, electrolytes, and nutrition. The discussion of mechanical ventilation includes rapid sequence induction and intubation, indication for intubation and extubation, and prognostic factors in mechanical ventilation. Differing blood pressure management concerns in hemorrhagic and ischemic events are discussed, and specific target blood pressures and pharmacologic interventions are reviewed. The discussion of cardiac monitoring includes concurrent stroke and cardiac ischemia and arrhythmias, cardiac imaging, anticoagulation, and vasopressor therapy. The importance, monitoring and management of cerebral blood flow and intracranial pressure (ICP) are discussed, and strategies for treatment of elevated ICP are outlined in detail. The discussion of vasospasm includes evaluation, prophylaxis, and treatment with medications, hypervolemic hemodilution, and angioplasty. Management of seizure and status epilepticus in stroke and subarachnoid hemorrhage are reviewed and current algorithms are presented. The management of fluids, electrolytes and enteral nutrition are also reviewed.

Protective effect of spinal cord stimulation on experimental early cerebral vasospasm. Conclusive results

In this study we investigate the effects of cervical spinal cord stimulation (cSCS) on experimental 'early spasm' in rabbits as described in personal previous experience (Acta Neurochir 2001;143:177-185). Twenty-four adult red Burgundy rabbits wearing a cervical epidural electrode underwent cerebral blood flow (CBF) and functional monitoring of early basilar spasm before and during cSCS. CBF changes, as a consequence of cSCS, occurred in 20 control animals. No CBF changes, consistent with no basilar artery vasospasm, occurred after subarachnoid haemorrhage (SAH) up to the end of the experiments in all the stimulated animals. The role of reversible functional sympathectomy in mediating the effect of spinal cord stimulation on early spasm is discussed. cSCS is able to prevent 'early spasm' due to SAH in all the animals studied, independently from the occurrence and the sign of stimulation induced CBF variations.

Inhibition of vasospasm with lymphocyte function-associated antigen—1 monoclonal antibody in a femoral artery model in rats

Object. The authors have previously shown that a monoclonal antibody (mAb) that recognizes intercellular adhesion molecule—1 (ICAM-1), also known as CD54, when administered systemically inhibits experimental vasospasm in a rat femoral artery model, suggesting that ICAM-1 and leukocyte-endothelial adhesion play a crucial role in the molecular chain of events leading to posthemorrhagic vasospasm. In this report the authors confirm this hypothesis with mAbs directed against lymphocyte function-associated antigen—1 ([LFA-1] CD11a/CD18), the molecule on the surface of leukocytes that interacts with ICAM-1.

Methods. Femoral arteries in 38 Sprague—Dawley rats were isolated and exposed to autologous blood. Twenty-nine animals were then randomized into three groups and received intraperitoneal injections of anti—LFA-1 mAb (10 rats), anti—ICAM-1 mAb (10 rats), or an isotype-matched control mAb (nine rats). Injections were administered at 3 hours and 3, 6, and 9 days after surgery. Before their deaths, six animals underwent spleen harvest, and splenocytes were used in fluorescence-activated cell sorter (FACS) analysis to verify saturation of appropriate binding sites. Animals were killed at 12 days and vessels were harvested for histological study and measurement of the luminal cross-sectional area. Nine animals were randomized as earlier, killed 24 hours after a single injection of mAb, and evaluated for periadventitial infiltration of granulocytes and macrophages. Results of FACS analysis demonstrated saturation of both LFA-1 and ICAM-1 binding sites in animals treated with the respective mAb. The mean ratios of blood-exposed to saline-exposed luminal cross-sectional areas (expressed as the percentage of lumen patency) were 90.1 ± 5.8% (mean ± standard error of the mean) for animals treated with the anti—LFA-1 mAb (p = 0.0218), 94.2 ± 3.3% for animals treated with the anti-ICAM-1 mAb (p = 0.0067), and 62 ± 7.4% for animals treated with the isotype-matched control mAb. Macrophage and granulocyte counts in the periadventitial region were 39.5 ± 3.2/hpf for animals treated with anti—LFA-1 mAb (p = 0.001), 42 ± 3.7/hpf for animals treated with anti—ICAM-1 mAb (p = 0.003), and 72.2 ± 6.2/hpf for control animals.

Conclusions. The systemic administration of anti—LFA-1 or anti—ICAM-1 mAb initiated 3 hours after exposure to autologous blood inhibits the development of delayed chronic vasospasm at 12 days in a rat femoral artery model and leads to a significant reduction in periadventitial inflammatory cells at 24 hours. The authors conclude that blocking the migration of inflammatory cells across the endothelial surface of an artery after adventitial exposure to blood prevents the initiation of biological cascades necessary for the subsequent development of chronic vasospasm.

Posttreatment with adenovirus-mediated gene transfer of calcitonin gene-related peptide to reverse cerebral vasospasm in dogs

OBJECT

Gene transfer to cerebral vessels is a promising new therapeutic approach for cerebral vasospasm after subarachnoid hemorrhage (SAH). This study was undertaken to explore whether a delayed treatment with adenovirus encoding the prepro-calcitonin gene-related peptide (CGRP), 2 days after initial blood injection, reduces cerebral vasospasm in a double-hemorrhage model of severe vasospasm in dogs.

METHODS

In 20 dogs, arterial blood was injected into the cisterna magna on Days 0 and 2. Thirty minutes after the second blood injection, the animals received either adenovirus encoding the prepro-CGRP gene (AdCMVCGRP-treated group, eight dogs) or adenovirus encoding the beta-galactosidase gene (AdCMVbeta gal-treated group, six dogs) under the cytomegalovirus (CMV) promoter. One group of dogs did not receive treatment and served as controls (control SAH group, six dogs). Angiography was performed on Days 0 and 7 to assess cerebral vasospasm. On Day 7 following angiography, the animals were killed and their brains were stained with X-gal to detect the distribution of gene expression. Cerebrospinal fluid (CSF) was also tested for CGRP immunoreactivity. Severe vasospasm was observed in control SAH dogs on Day 7, and the mean basilar artery (BA) diameter was 53.4 +/- 5.5% of the value measured on Day 0. Treatment with AdCMVbeta gal did not alter vasospasm (the BA diameter was 55 +/- 3.9% of that measured on Day 0). The leptomeninges and adventitia of the BAs of dogs treated using AdCMVbeta gal demonstrated positive staining with X-gal. High levels of CGRP were measured in CSF from dogs that received AdCMVCGRP. In the group treated with AdCMVCGRP, vasospasm was significantly reduced (the BA diameter was 78.2 +/- 5.3% of that measured on Day 0, p < 0.05 compared with the control SAH group and the AdCMVbeta gal group).

CONCLUSIONS

In a model of severe vasospasm in dogs, gene transfer of CGRP after injection of blood attenuated cerebral vasospasm after SAH.

Multimodal quantitation of the effects of endovascular therapy for vasospasm on cerebral blood flow, transcranial doppler ultrasonographic velocities, and cerebral artery diameters

OBJECTIVE

The goal of this study was to quantify the effects of endovascular therapy on vasospastic cerebral vessels.

METHODS

We reviewed the medical records for 387 patients with ruptured intracranial aneurysms who were treated at a single institution (University of California, Los Angeles) between May 1, 1993, and March 31, 2001. Patients who developed cerebral vasospasm and underwent cerebral arteriographic, transcranial Doppler ultrasonographic, and cerebral blood flow (CBF) studies before and after endovascular therapy for cerebral arterial spasm (vasospasm) were included in this study.

RESULTS

Forty-five patients fulfilled the aforementioned criteria and were treated with either papaverine infusion, papaverine infusion with angioplasty, or angioplasty alone. After balloon angioplasty (12 patients), CBF increased from 27.8 +/- 2.8 ml/100 g/min to 28.4 +/- 3.0 ml/100 g/min (P = 0.87); the middle cerebral artery blood flow velocity was 1 57.6 +/- 9.4 cm/s and decreased to 76.3 +/- 9.3 cm/s (P < 0.05), with a mean increase in cerebral artery diameters of 24.4%. Papaverine infusion (20 patients) transiently increased the CBF from 27.5 +/- 2.1 ml/100 g/min to 38.7 +/- 2.8 ml/100 g/min (P < 0.05) and decreased the middle cerebral artery blood flow velocity from 109.9 +/- 9.1 cm/s to 82.8 +/- 8.6 cm/s (P < 0.05). There was a mean increase in vessel diameters of 30.1% after papaverine infusion. Combined treatment (13 patients) significantly increased the CBF from 33.3 +/- 3.2 ml/100 g/min to 41.7 +/- 2.8 ml/100 g/min (P< 0.05) and decreased the transcranial Doppler velocities from 148.9 +/- 12.7 cm/s to 111.4 +/- 10.6 cm/s (P < 0.05), with a mean increase in vessel diameters of 42.2%.

CONCLUSION

Balloon angioplasty increased proximal vessel diameters, whereas papaverine treatment effectively dilated distal cerebral vessels. In our small series, we observed no correlation between early clinical improvement or clinical outcomes and any of our quantitative or physiological data (CBF, transcranial Doppler velocities, or vessel diameters).

Effects of iso- and hypervolemic hemodilution on regional cerebral blood flow and oxygen delivery for patients with vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND

Arterial vasospasm after subarachnoid hemorrhage may cause cerebral ischemia. Treatment with hemodilution, reducing blood viscosity, and hypervolemia, increasing cardiac performance and distending the vasospastic artery, are clinically established methods to improve blood flow through the vasospastic arterial bed.

METHOD

Eight patients with transcranial Doppler verified vasospasm after subarachnoid hemorrhage were investigated with global (two-dimensional (133)Xenon) and regional (three-dimensional (99 m)Tc-HMPAO) cerebral blood flow (CBF) measurements, before and after 1/iso- and 2/hypervolemic hemodilution. Hematocrit was reduced to 0.28 from 0.36. Hypervolemia was achieved by increasing blood volume by 1100 ml.

FINDINGS

Isovolemic hemodilution increased global cerebral blood flow from 52.25+/-10.12 to 58.56+/-11.73 ml * 100 g(-1) * min(-1) (p<0.05), but after hypervolemic hemodilution CBF returned to 51.38+/-11.34 ml * 100 g(-1) * min(-1). Global cerebral delivery rate of oxygen (CDRO(2)) decreased from 7.94+/-1.92 to 6.98+/-1.66 ml * 100 g(-1) * min(-1) (p<0.001) during isovolemic hemodilution and remained reduced, 6.77+/-1.60 ml * 100 g(-1) * min(-1) (p<0.001), after the hypervolemic hemodilution. As a test of the hemodilution effect on regional CDRO(2) an ischemic threshold was defined as the maximal amount of oxygen transported by a CBF of 10 ml * 100 g(-1) * min(-1) at a Hb 140 g/l which corresponds to a CDRO(2) of 1.83 ml * 100 g(-1) * min(-1). The brain volume with a CDRO(2) exceeding the ichemic threshold was 1300+/-236 ml before intervention. After isovolemic hemodilution the non-ischemic brain volume was reduced to 1206+/-341 (p<0,003). After hypervolemic hemodilution the non-ischemic brain volume remained reduced at 1228+/-347 ml (p<0.05).

INTERPRETATION

The present study of controlled isovolemic hemodilution demonstrated increased global CBF, but there was a pronounced reduction in oxygen delivery capacity. Both CBF and CDRO(2) remained decreased during further hypervolemic hemodilution. We conclude that hemodilution to hematocrit 0.28 is not beneficial for patients with cerebral vasospasm after SAH.

Risk of hemorrhage from unsecured, unruptured aneurysms during and after hypertensive hypervolemic therapy

OBJECTIVE

Hypertensive hypervolemic therapy for vasospasm is widely practiced. It is not clear, however, whether the use of hypertension and hypervolemia as a treatment for vasospasm risks hemorrhage from an unsecured, unruptured aneurysm.

METHODS

From 1991 to 2000, the neurovascular unit at the Massachusetts General Hospital treated 1908 aneurysms, of which 966 were ruptured. Forty patients with ruptured aneurysms had unsecured, unruptured aneurysms and underwent hypertensive hypervolemic therapy for vasospasm. Hypertension was induced by intravenously administered phenylephrine, norepinephrine, and/or dopamine, and hypervolemia was achieved by intravenously administered crystalloid and colloid solutions. The 24-hour mean arterial systolic blood pressure (SBP) and the 24-hour mean central venous pressure were calculated on the basis of hourly measurements during hypertensive hypervolemic treatment.

RESULTS

The 40 study patients harbored 124 aneurysms, of which 51 aneurysms were treated (clipping, 37; coiling, 14) by the time hypertensive hypervolemic therapy began, leaving 73 unsecured aneurysms at risk. The mean size of the unsecured aneurysms was 4.45 mm. Nineteen patients were treated with mild hypertension (SBP, 140-180 mmHg), 12 patients were treated with moderate hypertension (SBP, 180-200 mmHg), and 9 patients were treated with severe hypertension (SBP, >200 mmHg). The 24-hour mean SBP readings were 166.81 +/- 8.19, 187.57 +/- 5.79, and 204.01 +/- 3.75 mmHg for the mild, moderate, and severe hypertension groups, respectively. The mean central venous pressure was 10.43 +/- 3.89 mmHg. The mean course of hypertensive hypervolemic therapy was 7.25 days, and therapy began on mean post-subarachnoid hemorrhage Day 6.73. Twenty-eight aneurysms were eventually treated in later procedures (clipping, 25; coiling, 3). The mean interval to treatment was 6.93 months. In a treatment and follow-up period of 121.75 aneurysm-years of risk, there was no instance of hemorrhage.

CONCLUSION

Hypertension and hypervolemia do not seem to increase the risk of hemorrhage from unsecured, unruptured aneurysms in the acute setting or in their short-term natural history.

Therapeutic approaches to vasospasm in subarachnoid hemorrhage

Delayed vasospasm as a result of subarachnoid blood after rupture of a cerebral aneurysm is a major complication. It is seen in over half of patients and causes symptomatic ischemia in about one third. If left untreated, it leads to death or permanent deficits in over 20% of patients. The essential cause and the relative contribution of true muscle spasm and other changes in the vessel wall remain uncertain. The mainstays of treatment are careful maintenance of fluid balance, induced hypervolemia and hypertension, calcium antagonists, balloon or chemical angioplasty, and, in some centers, cisternal fibrinolytic drugs. Promising future lines of treatment include gene therapy, nitric oxide donors, magnesium, sustained release cisternal drugs, and several other drugs that are under experimental or clinical trial.

Vasospasm model of a rabbit common carotid artery for endovascular research

RATIONALE AND OBJECTIVES

Endovascular treatments such as balloon angioplasty and injection of vasodilators play an important role in cerebral vasospasm refractory to first-line therapies. Experimental studies with intracranial arteries of animals have some limitations, however, because in most cases endovascular devices are too large and inflexible to catheterize these arteries. The purpose of this study was to document the natural course of a vasospasm model using a rabbit common carotid artery.

MATERIALS AND METHODS

The common carotid arteries of 24 New Zealand white rabbits were used. Autologous blood was placed around the isolated artery and kept in place with a silicone cuff. The time course of vasoconstriction after blood clot placement was examined with angiography and with histopathologic evaluation.

RESULTS

Angiographic vasoconstriction was prominent on day 2, less obvious on day 9, and absent on day 30. At histopathologic evaluation, folding of the endothelial surface, corrugation of the internal elastic lamina, and thickening of the arterial wall were observed in the group with blood clot placements around the artery on day 2 and were nearly absent on day 30.

CONCLUSION

This model may be used for the study of endovascular treatments of vasospasm.

Safety of intraventricular sodium nitroprusside and thiosulfate for the treatment of cerebral vasospasm in the intensive care unit setting

BACKGROUND AND PURPOSE

We have recently reported the safety of intraventricular sodium nitroprusside for the treatment of cerebral ischemia from vasospasm. Treatments have been accompanied previously by cerebral angiography to gauge treatment effect on established vasospasm. We presently report the safe coadministration of intraventricular sodium nitroprusside and thiosulfate in 10 patients with secured ruptured cerebral aneurysms in the intensive care unit, without the use of cerebral angiography for vasospasm treatment.

METHODS

Patients were considered eligible for treatment on the basis of subarachnoid hemorrhage grade or manifestation of cerebral vasospasm by either transcranial Doppler ultrasonography (TCD) or neurological examination criteria. The route of administration was intraventricular, by way of ventriculostomy. Two separate protocols differing in dosage frequency were used, depending on the presence or absence of a new neurological deficit. Response to treatment was measured by TCD and neurological criteria.

RESULTS

Good outcome was observed in 7 of 8 vasospasm patients presenting with clinical subarachnoid hemorrhage grade > or =3. Four patients demonstrated reversal of well-defined neurological deficits (hemiparesis, paraparesis) in the setting of treatment. Seven patients demonstrated a decrease in TCD velocities within 1 hour of treatment. Two patients died: 1 from intractable vasospasm despite maximal medical management and angioplasty and 1 from pulmonary causes. One episode of hypotension occurred in the setting of a high dose of medication. This responded promptly to medical management. Prolonged intracranial hypertension did not occur; modest elevations of both intracranial pressure and mean arterial blood pressure were observed when nausea and vomiting were associated with treatment, which occurred commonly in awake subjects.

CONCLUSIONS

Intraventricular sodium nitroprusside with thiosulfate may be safely administered in the intensive care unit setting without the requirement of cerebral angiography to guide the effects of therapy.