Analysis of human sera for filarial IgM antibody using antigen fractions isolated from immune complexes

OBJECTIVES: To assess the efficacy of nimodipine in preventing delayed ischaemic deficit in aneurysmal subarachnoid haemorrhage. DESIGN: A continuous prospective audit of all patients with aneurysmal subarachnoid haemorrhage admitted to the joint neurosurgery units of Prince Henry's and Alfred hospitals, Melbourne. Patients were divided into two groups--135 in the pre-nimodipine group during 1986 to 1989, and 73 in the nimodipine group during 1989 and 1990. MAIN OUTCOME MEASURES: Outcome was measured according to the Glasgow outcome scale and the incidence of delayed ischaemic deficit was recorded. RESULTS: A substantial reduction in the overall incidence of poor outcome was observed, from 37% of patients in the non-nimodipine group, to 20% in the nimodipine group (P = 0.022). Delayed ischaemic deficit occurred in 41% and 21% (P = 0.005), and poor outcome due to delayed ischaemic deficit occurred in 18% and 8% (P = 0.09) respectively. CONCLUSIONS: In our experience, nimodipine appears to have substantially reduced the incidence of delayed ischaemic deficits in patients with aneurysmal subarachnoid haemorrhage, with a resultant improvement in overall patient outcome.     

Mild hypothermia as a protective therapy during intracranial aneurysm surgery: a randomized prospective pilot trial

OBJECTIVE: To conduct a pilot trial of mild intraoperative hypothermia during cerebral aneurysm surgery. METHODS: One hundred fourteen patients undergoing cerebral aneurysm clipping with (n = 52) (World Federation of Neurological Surgeons score < or =III) and without (n = 62) acute aneurysmal subarachnoid hemorrhage (SAH) were randomized to normothermic (target esophageal temperature at clip application of 36.5 degrees C) and hypothermic (target temperature of 33.5 degrees C) groups. Neurological status was prospectively evaluated before surgery, 24 and 72 hours postoperatively (National Institutes of Health Stroke Scale), and 3 to 6 months after surgery (Glasgow Outcome Scale). Secondary outcomes included postoperative critical care requirements, respiratory and cardiovascular complications, duration of hospitalization, and discharge disposition. RESULTS: Seven hypothermic patients (12%) could not be cooled to within 1 degrees C of target temperature; three of the seven were obese. Patients randomized to the hypothermic group more frequently required intubation and rewarming for the first 2 hours after surgery. Although not achieving statistical significance, patients with SAH randomized to the hypothermic group, when compared with patients in the normothermic group, had the following: 1) a lower frequency of neurological deterioration at 24 and 72 hours after surgery (21 versus 37-41%), 2) a greater frequency of discharge to home (75 versus 57%), and 3) a greater incidence of good long-term outcomes (71 versus 57%). For patients without acute SAH, there were no outcome differences between the temperature groups. There was no suggestion that hypothermia was associated with excess morbidity or mortality. CONCLUSION: Mild hypothermia during cerebral aneurysm surgery is feasible in nonobese patients and is well tolerated. Our results indicate that a multicenter trial enrolling 300 to 900 patients with acute aneurysmal SAH will be required to demonstrate a statistically significant benefit with mild intraoperative hypothermia.     

Timing of surgery in patients with aneurysmal subarachnoid haemorrhage: rebleeding is still the major cause of poor outcome in neurosurgical units that aim at early surgery

OBJECTIVE: To investigate prospectively the proportion of patients actually operated on early in units that aim at surgery in the acute phase of aneurysmal subarachnoid haemorrhage (SAH) and what is the main current determinant of poor outcome. METHODS: A prospective analysis of all SAH patients admitted during a one year period at three neurosurgical units that aim at early surgery. The following clinical details were recorded: age, sex, date of SAH, date of admission to the neurosurgical centre, whether a patient was referred by a regional hospital or a general practitioner, Glasgow coma scale and grade of SAH (World Federation of Neurological Surgeons (WFNS) score) on admission at the neurosurgical unit, results of CT and CSF examination, the presence of an aneurysm on angiography, details of treatment with nimodipine or antifibrinolytic agents, and the date of surgery to clip the aneurysm. At follow up at three months, the patients' clinical outcome was determined with the Glasgow outcome scale and in cases of poor outcome the cause for this was recorded. RESULTS: The proportion of patients that was operated on early--that is, within three days after SAH--was 55%. Thirty seven of all 102 admitted patients had a poor outcome. Rebleeding and the initial bleeding were the main causes of this in 35% and 32% respectively of all patients with poor outcome. CONCLUSIONS: In neurosurgical units with what has been termed "modern management" including early surgery, about half of the patients are operated on early. Rebleeding is still the major cause of poor outcome.     

Prognostic factors for adenocarcinoma of the gallbladder: an analysis of 162 cases

We experienced a case with sudden unexpected death caused by rupture of an intracranial aneurysm, which was confirmed by autopsy. Depending on this case, we reported the significance of the cerebellar tonsillar herniation on the cause of sudden death of ruptured cerebral aneurysm. A 58-year-old man was admitted to us for treatment of subarachnoid hemorrhage (SAH). The CT scanning showed diffuse SAH in the whole cistern. Cerebral angiography on admission revealed an aneurysm at the bifurcation of the left middle cerebral artery in association with bleb like configuration. The aneurysmal neck was clipped on the day of admission. The postoperative course was uneventful. In the early morning of postoperative 23rd day, he was found being expired. To clarify the cause of death, an autopsy was done, disclosing diffuse SAH in association with tonsillar herniation more marked on the left. Thus, the distortion of the spinomedullary junction due to asymmetrical herniation was considered to be responsible for unexpected sudden death in this case. Examination of the major cerebral artery disclosed a ruptured anterior communicating artery aneurysm.     

Dermal application of lisuride on parkinsonism induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the common marmoset and on cases with Parkinson''s disease

BACKGROUND: Follow-up study of patients with surgical repair of aneurysmal subarachnoidal hemorrhage (SAH), looking for clinical outcome predictors. PATIENTS AND METHODS: Sixty two patients consecutively admitted to a teaching hospital, from January 1992 to December 1995 were included in the study. We studied preoperative, intraoperative and postoperative features looking for their relationship with the outcome. The ultimate outcome was evaluated by means of Glasgow Outcome Scale on discharge and 6 months later. RESULTS: Smoking (p = 0.0001) and arterial hypertension (AHT) (p = 0.0186) were more frequent in these patients than in general population, but without relationship to the outcome as with the age of the clinical status on admission. The greatest statistical relationship was found between the level of consciousness on postoperative awakening (measured by the Hunt and Hess scale), and the outcome (p = 2.53 x 10(-8). From our results we made an algorithm that correctly assigned 92% of studied patients to their outcome. CONCLUSIONS: All patients admitted on with aneurysm SAH deserve intensive care treatment besides their clinical grade. The level of consciousness on postoperative awakening was a good outcome predictor.     

Management of subarachnoid hemorrhage patients who presented with respiratory arrest resuscitated with bystander CPR

BACKGROUND AND PURPOSE: The sudden death rate from aneurysmal subarachnoid hemorrhage (SAH) is 10%. Since 1989, 26 SAH patients who were witnessed to collapse into coma with respiratory arrest and required cardiopulmonary resuscitation (CPR) at the scene survived to reach the hospital and be diagnosed. Although reports on hospital management of grade V SAH suggest improved outcome, no report has previously addressed the issue of respiratory arrest after acute SAH. We analyze our experience with this unique subgroup of aneurysmal SAH patients. METHODS: This is a retrospective analysis of 26 consecutive SAH patients who collapsed at the scene and required CPR for respiratory arrest and survived to reach the hospital and be diagnosed. Statistical analysis was performed using the t test and Mann-Whitney rank-sum test. RESULTS: All patients were grade V on arrival at the emergency department. Twenty-one patients received mouth-to-mouth resuscitation only, and 5 received chest compressions as well. The mean duration of bystander CPR was 12 to 15 minutes. CT scan showed diffuse, thick SAH in all patients, an associated subdural hemorrhage in 2, and an intraparenchymal hemorrhage in 4. After CT scan, an intracranial pressure (ICP) monitor was placed in 24, and 2 were taken to emergency surgery for subdural and intracerebral hemorrhage. ICP was elevated in 24 patients (mean, 54 mm Hg), and a ventriculostomy was placed in all 24. ICP was unresponsive in 12, and all suffered brain death. ICP lessened to < 25 mm Hg in 12, and all underwent angiography. All 12 had an aneurysm and underwent emergency surgical clipping. Time to surgery from SAH was < or = 11 hours in all 12 patients. All were managed with calcium channel blockers and hyperdynamic therapy in addition to aggressive control of ICP. The outcome at 12 months in the 14 surgical cases was normal in 3 patients (21%), good in 2 (14%), vegetative in 1 (7%), and death in 8 (57%). CONCLUSIONS: Aneurysmal SAH patients that present with respiratory arrest present as grade V patients with elevated ICP. Bystander CPR coupled with early retrieval, diagnosis, and therapy can lead to 20% functional survival in what used to be sudden death from aneurysmal SAH.     

Neuroprotective effect of an antioxidant, ebselen, in patients with delayed neurological deficits after aneurysmal subarachnoid hemorrhage

OBJECTIVE: The effect of ebselen, a seleno-organic compound with antioxidant activity through a glutathione peroxidase-like action, on the outcome of subarachnoid hemorrhage was evaluated in a multicenter placebo-controlled double-blind clinical trial. METHODS: Patients who suffered aneurysmal subarachnoid hemorrhages of Hunt and Kosnik Grades II through IV at admission and were able to start drug treatment within 96 hours of the ictus were enrolled. Early surgery was performed whenever possible. Oral administration of ebselen granules suspended in water (150 mg, twice a day) or placebo was started immediately after admission and continued for 2 weeks. The major end points were the Glasgow Outcome Scale at 2 weeks, 1 month, and 3 months after the start of treatment. The incidence of delayed ischemic neurological deficits clinically diagnosed as resulting from vasospasm and the incidence and extent of low-density areas on postoperative computed tomographic scans were also studied as secondary outcome measures. RESULTS: Intent-to-treat analysis of the 286 patients enrolled in the trial (145 patients administered ebselen and 141 administered placebo) revealed that the incidence of clinically diagnosed delayed ischemic neurological deficits was unaltered. There were 52 (receiving ebselen) and 58 (receiving placebo) patients with delayed deficits; however, a significantly better outcome was observed after ebselen treatment than after placebo (P = 0.005, chi2 test). There was a corresponding decrease in the incidence and extent of low-density areas (P = 0.032, Wilcoxon rank sum test). CONCLUSION: Ebselen reduced brain damage in patients with delayed neurological deficits after subarachnoid hemorrhage and may be a promising neuroprotective agent.     

Effect of ultra-early referral on management outcome in subarachnoid haemorrhage

A study was conducted to clarify whether ultra-early referral of patients with subarachnoid haemorrhage (SAH) is effective for improving the management outcome. The subjects were 455 patients who were admitted within 6 h after initial SAH. Of these patients, 289 were treated surgically, 159 of them within 24 h. At 6 months, 228 patients (50%) had a favourable outcome including good recovery or moderate disability, 37 (8%) had severe disability, and 190 (42%) had an unfavourable outcome including vegetative state or death. Of 214 patients with an admission grade IV or V, 47 (22%) had a favourable outcome. In 10 patients, emergency procedures such as haematoma removal or ventriculostomy were definitely effective, and in 13, early surgery may have been the reason for the improved outcome. However, in 24 patients, the reasons for a favourable outcome were not related directly to ultra-early referral; in 19 of them, there was spontaneous improvement of clinical grade and/or no SAH on computed tomography. Of 218 patients with admission grade I or II, 30 (14%) had an unfavourable outcome, and in 12 of them, this was ascribed to rebleeding. The rebleeding rate and severity of vasospasm were not significantly reduced by surgery carried out within 24 h after SAH, in comparison with surgery carried out between 24 and 48 h, and there was no significant difference in surgical outcome between them. It is concluded that although ultra-early referral of patients with SAH was expected to improve the outcome in emergency cases, no substantial improvement in overall management outcome seems to have been achieved by this policy.     

Predictive factors for in-hospital mortality and delayed mortality following aneurysmal subarachnoid hemorrhage

It is important to detect predictive factors for in-hospital and delayed mortality of patients with subarachnoid hemorrhage (SAH) due to ruptured aneurysm. Forty-eight patients with initial bleeding of aneurysmal SAH were referred to our hospital from January 1982 to December 1985. In-hospital mortality was 16.7% (8 to 48), and 15% (6) of forty patients died later during the follow-up period. Using the Kaplan-Meier method we were able to conclude that, cumulatively, there was 70.8% probability that much patients would survive for 10 years. We analysed predictive factors of in-hospital and delayed mortality retrospectively. The most significant predictive factor for in-hospital mortality was SAH grading on admission, and for delayed mortality (29.2%) age on admission was the best predictive factor. In fact, two patients died with cardiac event during the follow-up period. This result suggests that, although the SAH grading on admission was the second most significant factor for delayed mortality, patients who survived in the acute phase had a survival probability similar to those in a normal control group.     

Risk of recurrent subarachnoid hemorrhage after complete obliteration of cerebral aneurysms

BACKGROUND and PURPOSE: The neck clipping of cerebral aneurysms is a well-established treatment for subarachnoid hemorrhage (SAH) caused by aneurysmal rupture. However, it is still unclear how great a risk of recurrence patients with a successfully treated aneurysm carry over a long-term period. METHODS: Of 425 patients with SAH surgically treated in Aizu Chuou Hospital from 1976 to 1994, 220 cases meeting the following criteria were studied: (1) all aneurysms detected by 3- or 4-vessel cerebral angiography were clipped, (2) complete obliteration of aneurysm(s) was confirmed by postoperative angiography, and (3) the patient survived >3 years. All patients were traced until January 1998 for recurrent SAH or death. The mean follow-up period was 9.9 (range, 3 to 21) years. RESULTS: Six patients (2.7%) had recurrent SAH, each with an interval ranging from 3 to 17 years (mean, 11 years) since the original treatment. In addition, 2 patients were found to have regrowth of the originally operated aneurysms. The cumulative recurrence rate of SAH, calculated using the Kaplan-Meier method, was 2.2% at 10 years and 9. 0% at 20 years after the original treatment. CONCLUSIONS: The recurrence rate was considerably higher than the previously reported risk of SAH in the normal population, and the rate increased with time. These data indicate that patients with ruptured cerebral aneurysms still carry higher risks for SAH in a long-term period, even after complete obliteration of the aneurysm, and that periodic examination to detect recurrent aneurysms may be indicated for such patients.     

Outcome after aneurysmal subarachnoid haemorrhage: the use of a graphical model in the assessment of risk factors

In 102 consecutive prospectively identified patients with subarachnoid haemorrhage (SAH) we have analysed the severity of the initial haemorrhage and the direct and indirect effects of adverse factors on outcome. The data we recorded included delay in diagnosis, risk groups, Doppler measurements, angiographic findings, surgical events and outcome at 1 year. By using a temporal graphical chain model, the associations between all variables and possible causal pathways were statistically determined. The severity of the initial haemorrhage, as determined by means of a clinical assessment and CT scanning, allowed low-, medium- and high-risk patient groups and a statistically predictable outcome to be identified. The overall management mortality was 13.7% at 1 year; 70.6% had a favourable outcome and 15.7% were severely disabled. Outcome was directly associated with risk group (p = 0.0038) and rebleeding (p = 0.0000). Delayed diagnosis led to a poorer outcome (p = 0.014)--an indirect association probably due to rebleeding. Adverse surgical events led to a significantly poorer outcome in high-risk patients. No significant relationship was found either between age and risk group (p = 0.7784) or between age and outcome (p = 0.6418). Preoperative clinical (WFNS) grade was unreliable in predicting outcome. It is the particular risk group, determined by the initial SAH, that indicates the individual patient's outcome. Management strategies can reduce preventable adverse events such diagnostic delay and rebleeding. Future studies should stratify patients according to risk group, delay in diagnosis and rebleeding in order to enable a clearer comparison to be made of treatment methods.     

Subarachnoid hemorrhage: protective hypotension in delayed surgery

Systemic hypertension is frequently observed in patients with subarachnoid haemorrhage (SAH). Continuing systemic hypertension might augment the risk of rebleeding and also increase the blood flow and blood volume, resulting in more marked cerebral edema and intracranial hypertension. However, reduction of blood pressure might also decrease cerebral perfusion pressure in patient with an impaired autoregulation and in this way enhance the risk of cerebral ischemia. Anti-hypertensive therapy is not recommended to prevent rebleeding after SAH. The agents of choice for reduction of arterial blood pressure might be mixed alfa and beta adrenergic antagonists and barbiturates.     

Plasma glucose levels and outcome after aneurysmal subarachnoid hemorrhage

Plasma glucose levels were studied in 616 patients admitted within 72 hours after subarachnoid hemorrhage (SAH). Glucose levels measured at admission showed a statistically significant association with Glasgow Coma Scale scores, Botterell grade, deposition of blood on computerized tomography (CT) scans, and level of consciousness at admission. Elevated glucose levels at admission predicted poor outcome. A good recovery, as assessed by the Glasgow Outcome Scale at 3 months, occurred in 70.2% of patients with normal glucose levels (< or = 120 mg/dl) and in 53.7% of patients with hyperglycemia (> 120 mg/dl) (p = 0.002). The death rates for these two groups were 6.7% and 19.9%, respectively (p = 0.001). The association was still maintained after adjusting for age (> or < or = 50 years) and thickness of clot on CT scans (thin or thick) in the subset of patients who were alert/drowsy at admission. Increased mean glucose levels between Days 3 and 7 also predicted a worse outcome; good recovery was observed in 132 (73.7%) of 179 patients who had normal mean glucose levels (< or = 120 mg/dl) and 160 (49.7%) of 322 who had elevated mean glucose levels (> 120 mg/dl) (p < 0.0001). Death occurred in 6.7% and 20.8% of the two groups, respectively (p < 0.0001). It is concluded that admission plasma glucose levels can serve as an objective prognostic indicator after SAH. Elevated glucose levels during the 1st week after SAH also predict a poor outcome. However, a causal link between hyperglycemia and outcome after delayed cerebral ischemia, although suggested by experimental data, cannot be established on the basis of this study.     

Intercomparison of four reconstruction techniques for positron volume imaging with rotating planar detectors

Middle cerebral artery (MCA) aneurysms account for approximately 20% of aneurysmal subarachnoid hemorrhage (SAH). An understanding of MCA anatomy and variations is the key to successful treatment of MCA aneurysms, which may occur on the M1 segment, at the division of the main trunk or on distal branches. Patients may present with SAH, mass effect, epilepsy, or ischemia. MCA aneurysms associated with large temporal hematomas may be approached through the superior temporal gyrus. Other aneurysms are best approached with a medial or lateral transSylvian approach.     

The safety of intraoperative lumbar subarachnoid drainage for acutely ruptured intracranial aneurysm: technical note

Recently, some concern has arisen regarding the safety of intraoperative spinal drainage for brain relaxation in aneurysm surgery, due to anecdotal association with both aneurysmal rebleeding and increases in symptomatic vasospasm. To address these concerns, we reviewed our experience with frequent spinal drainage and early surgery in 432 consecutive cases of surgically treated aneurysmal subarachnoid hemorrhage. Unless contraindicated by mass effect or associated pathology, all grade I-III patients referred within 14 days were treated with spinal drainage at surgery. In this cohort (n = 314), there were no cases of meningitis or nerve root injury. Only one case of intraoperative rebleeding could be associated with spinal drain placement (0.3%). In grade IV-V patients, 47% required preoperative ventriculostomy, and 11% were ineligible for spinal drainage due to mass effect. There were, however, no complications related to spinal drainage in the remaining 23 patients. Permanently-shunted hydrocephalus (8%) and symptomatic vasospasm (19%) were infrequent overall. When analyzed by grade, spinal drains were generally associated with equal or reduced incidence of these developments when compared to patients without spinal drainage. We conclude that brain relaxation can be safely and effectively obtained using intraoperative spinal drains during early aneurysm surgery.     

Failure of platelet angiotensin II binding to predict pregnancy-induced hypertension

OBJECT: Nimodipine therapy has become a standard component of the treatment regimen used in patients with aneurysmal subarachnoid hemorrhage (SAH). Its prescribed use at 60 mg every 4 hours for 21 days is based on reputable, randomized prospective studies. However, because only 20 to 30% of patients with SAH suffer clinical cerebral vasospasm, it is clear that most patients do not actually need the drug. Of course, this fact is not evident until several treatment days have passed. It is common practice, without well-documented consequences, to terminate nimodipine therapy before 21 days in certain clinical circumstances. The aim of this study was to evaluate the effectiveness of abbreviating the duration of nimodipine treatment in the setting of a good-grade aneurysmal SAH. METHODS: A retrospective clinical review was made of 90 consecutive patients who experienced a Hunt and Hess Grade I through III aneurysmal SAH and were treated with nimodipine for 15 days or less. CONCLUSIONS: None of the patients studied suffered a delayed neurological deficit as a result of the abbreviated course of nimodipine.     

Calcitonin gene-related peptide reduces brain injury in a rat model of focal cerebral ischemia

BACKGROUND AND PURPOSE: Calcitonin gene-related peptide is an endogenous vasodilating neuropeptide with a dense concentration in the trigeminocerebrovascular system. It is hypothesized that depletion of this peptide contributes to delayed cerebral ischemia after subarachnoid hemorrhage and that an exogenous supply of calcitonin gene-related peptide will augment ischemic cerebral blood flow and reduce neuronal injury. METHODS: In this study we have investigated the effect of an intravenous infusion of calcitonin gene-related peptide (100 ng/kg per minute), started 1 hour before and continued throughout 4 hours of focal cerebral ischemia, on cerebral blood flow and the volume of brain injury in a rat model of middle cerebral artery occlusion. RESULTS: Calcitonin gene-related peptide produces a significant improvement in ischemic cerebral blood flow (32 +/- 2 compared with 13 +/- 2 mL/100 g per minute in the controls; t = 6.92, P < .0001) with a concomitant reduction in the volume of ischemic brain injury (102 +/- 22 compared with 234 +/- 19 mm3; t = 4.47, P < .001). CONCLUSIONS: These findings lend support for the potential use of this peptide in the prophylactic treatment of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.     

Cardiac outcome in patients with subarachnoid hemorrhage and electrocardiographic abnormalities

OBJECTIVE: Approximately 25% of patients with subarachnoid hemorrhage (SAH) have electrocardiographic (ECG) abnormalities consistent with myocardial ischemia or myocardial infarction (MI), and their cardiac prognosis remains unclear. The objective of this study was to determine the cardiac and all-cause mortality rate of a series of patients with SAH with ECG changes consistent with ischemia or MI. METHODS: Using an existing database of patients with SAH and predetermined ECG criteria for ischemia or MI, a study group of patients with abnormal ECG results within 3 days of presentation and before aneurysm surgery was identified. Database patients without abnormal ECG results served as a control group. Cardiac mortality, defined as death resulting from arrhythmia, congestive heart failure, or cardiogenic shock, was assessed by chart review. RESULTS: Of 439 patients with SAH in the database, 58 met the criteria for the study group. Forty-one of these patients were treated neurosurgically. No deaths resulting from cardiac causes occurred, and 20 patients died as a result of noncardiac causes. In a multivariable analysis, age older than 65 years and Hunt and Hess grade of at least 3 were predictive of all-cause mortality. ECG abnormalities, however, were not a statistically significant predictor. CONCLUSION: In patients with SAH and ECG readings consistent with ischemia or MI, the risk of death resulting from cardiac causes is low, with or without aneurysm surgery. The ECG abnormalities are associated with more severe neurological injury but are not independently predictive of all-cause mortality.     

Acute vasoconstriction after subarachnoid hemorrhage

OBJECTIVE: Decreased cerebral blood flow (CBF) and cerebral ischemia occurring immediately after subarachnoid hemorrhage (SAH) may be caused by acute microvascular constriction. However, CBF can also be influenced by changes in intracranial pressure (ICP) and cerebral perfusion pressure (CPP). The goal of these experiments was to assess the significance of acute vasoconstriction after SAH and its relationship to changes in CBF, ICP, CPP, and extracellular glutamate concentrations. METHODS: Three experiments were performed using the endovascular filament technique to produce SAH. In the first experiment, CBF, ICP, and CPP were measured for 60 minutes after SAH (n = 21) and were correlated with the 24-hour mortality rate. In the second experiment, rats undergoing SAH (n = 23) or a sham procedure (n = 7) were perfused 60 minutes after SAH for measurement of the circumference and wall thickness of the internal carotid and anterior cerebral arteries and correlation with CBF, ICP, and CPP. In the third experiment (n = 11), extracellular glutamate concentrations determined by hippocampal and cortical microdialysis and high performance liquid chromatography were correlated with physiological changes. RESULTS: CBF reductions to less than 40% of baseline for 60 minutes after SAH predicted 24-hour mortality with 100% accuracy and were used to define "lethal" SAH. In contrast, ICP and CPP 60 minutes after SAH were not correlated with the mortality rate. The vascular circumference was significantly smaller in lethal than in sublethal SAH or sham-operated rats (P < 0.001). Vessel measurements were correlated with both CBF and hemorrhage size (P < 0.01). Extracellular glutamate concentration increased to 600% of baseline after lethal SAH in both hippocampus and cortex and was inversely correlated with CBF (r = 0.9, P < 0.001) but did not increase after sublethal SAH. CONCLUSION: Acute vasoconstriction after SAH occurs independently of changes in ICP and CPP and is associated with decreased CBF, larger hemorrhage size, persistent elevations of extracellular glutamate, and poor outcome. Acute vasoconstriction seems to contribute directly to ischemic brain injury after SAH. Further evaluations of pharmacological agents with the potential to reverse acute vasoconstriction may increase CBF and improve outcome.     

Comprehensive treatment of intracranial aneurysm complicated by postoperative vasospasm

Forty six patients suffered from intracranial aneurysm complicated by postoperative vasospasm and delayed cerebral ischemia were monitored dynamically both by clinical observation of neurologic status and multiple items such as transcranial Doppler, serum osmolality, intracranial pressure and other somatic physiologic items related to monitoring. Patients were intensively and comprehensively treated according to individualized grading of vasospasm. Forty four patients (95.6%) were completely recovered from postoperative vasospasm and delayed cerebral ischemia, while 2 patients (4.3%) complicated by hemipalsy as a consequence of delayed cerebral ischemia. The occurrence of vasospasm and delayed cerebral ischemia, the criteria of TCD grading, the valuableness of multiple physiologic items and problems related to comprehensive treatment are discussed.