Cerebral vasospasm and delayed cerebral ischemia in intraventricular hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) with intraventricular extension (IVH) is a devastating disease with a particular high mortality. In some aspects, IVH may resemble subarachnoid hemorrhage. The incidence and role of cerebral vasospasm in ICH with IVH are poorly understood. Here, we aimed to analyze the incidence and relationship of cerebral vasospasm to clinical characteristics, in-hospital mortality, and functional outcome at 3 months in patients suffering ICH with IVH.

METHODS

Patients with ICH and IVH treated on a neurological intensive care unit were prospectively enrolled in a single-center observational study. Vasospasm was defined using established ultrasound criteria. Delayed cerebral ischemia (DCI) was defined as a new hypodensity on follow-up cranial CT. Functional outcome at 3 months was assessed using the modified Rankin Scale.

RESULTS

129 patients with ICH and IVH were screened for the study. 62 patients entered the final analysis. The incidence of significant vasospasm was 37 %. A strong trend was found for the association between all cerebral vasospasm and DCI (P = 0.046). Early (up to 48 h) vasospasm was significantly associated with a DCI (P = 0.033). Overall mortality and outcome after 3 months did not differ between the groups.

CONCLUSION

Cerebral vasospasm seems to be a frequent complication after ICH with IVH and might be associated with DCI. Larger studies are warranted to confirm this hypothesis.

Comparison of three rat models of cerebral vasospasm

A substantial number of rat models have been used to research subarachnoid hemorrhage-induced cerebral vasospasm; however, controversy exists regarding which method of selection is appropriate for this species. This study was designed to provide extensive information about the three most popular subarachnoid hemorrhage rat models: the endovascular puncture model, the single-hemorrhage model, and the double-hemorrhage model. In this study, the basilar artery and posterior communicating artery were chosen for histopathological examination and morphometric analysis. Both the endovascular puncture model and single-hemorrhage model developed significant degrees of vasospasm, which were less severe when compared with the double-hemorrhage model. The endovascular puncture model and double-hemorrhage model both developed more vasospasms in the posterior communicating artery than in the basilar artery. The endovascular puncture model has a markedly high mortality rate and high variability in bleeding volume. Overall, the present study showed that the double-hemorrhage model in rats is a more suitable tool with which to investigate mechanism and therapeutic approaches because it accurately correlates with the time courses for vasospasm in humans.

Efficacy of prophylactic nimodipine for delayed ischemic deficit after subarachnoid hemorrhage: a metaanalysis

The authors report findings from a metaanalysis of all published randomized trials of prophylactic nimodipine used in patients who have experienced subarachnoid hemorrhage (SAH). Seven trials were included with a total of 1202 patients suitable for evaluation. Eight outcome measures were examined, including good versus other outcome, good or fair outcome versus other outcome, overall mortality, deficit and/or death attributed to vasospasm, infarction rate as judged by computerized tomography (CT), and deficit and/or death from rebleeding. Nimodipine improved outcome according to all measures examined. The odds of good and of good plus fair outcomes were improved by ratios of 1.86:1 and 1.67:1, respectively, for nimodipine versus control(p<0.005 for both measures). The odds of deficit and/or mortality attributed to vasospasm and CT-assessed infarction rate were reduced by ratios of 0.46:1 to 0.58:1 in the nimodipine group (p<0.008 for all measures). Overall mortality was slightly reduced in the nimodipine group, but the trend was not statistically significant. The rebleeding rate was not increased by nimodipine. A metaregression yielded findings indicating that the treatment effect of nimodipine in individual trials was positively correlated with the severity of SAH in enrolled patients. Although the majority of individual trials examined did not have statistically significant results at the p<0.01 level according to most outcome measures, the metaanalyses confirmed the significant efficacy of prophylactic nimodipine in improving outcome after SAH under the conditions used in these trials.

Early treatment of ruptured aneurysms with Guglielmi detachable coils: effect on subsequent bleeding

The major causes of mortality and morbidity in patients surviving the rupture of a saccular aneurysm are subsequent bleeding and vasospasm. The purpose of this study was to evaluate the influence of early treatment of ruptured aneurysms with Guglielmi detachable coils on the incidence of subsequent bleeding. Thirteen patients were treated within 72 hours of initial aneurysm rupture with Guglielmi detachable coils. Excluding three patients who died 2, 4, and 12 weeks after initial hemorrhage, all others have been followed up for intervals between 6 and 36 months (mean, 16 mo). None of these have had either clinical or radiographic evidence of subsequent bleeding. Assuming that there is a 30% incidence of subsequent bleeding in conservatively (nonsurgically) treated patients, the 0% subsequent bleed rate observed in this subgroup was significant at a P value of 0.01. Only one procedure-related complication occurred in this series, and 9 of 13 (69%) aneurysms were 100% occluded at the time of initial treatment. All aneurysms were at least 90% occluded at the end of initial treatment. In addition to reducing the risk of subsequent bleeding, early treatment facilitated the institution of an aggressive approach for management of both vasospasm and increased intracranial pressure. Patient outcome, as measured by the Glasgow Outcome Scale, was good in 9 of 13 (69%), poor in 1 of 13 (8%), and death in 3 of 13 (23%) patients. The results of this study suggest that early Guglielmi detachable coil treatment of ruptured aneurysms may be effective in reducing the incidence of subsequent bleeding and can be performed with a low incidence of complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Intracranial aneurysms in autosomal dominant polycystic kidney disease

Rupture of intracranial aneurysm (ICA) is a rare but severe manifestation of autosomal dominant polycystic kidney disease (ADPKD). In order to assess its natural history, to determine the prevalence of familial aggregation and to document linkage to PKD1 locus, we conducted a retrospective study on 77 ADPKD patients from 64 families presenting with ruptured (N = 71) or unruptured (N = 6) aneurysm. Information was collected on kidney disease, intracranial aneurysm and family history. Linkage to PKD1 locus was examined by five probes to obtain informative flanking markers. Within one year prior to rupture, blood pressure was normal in 29% of the patients. At the time of rupture, mean age was 39.5 years (range 15 to 69), renal function was normal in half of the patients and 11% were on renal replacement therapy. The ruptured aneurysm was usually located on the middle cerebral artery. Additional intact aneurysms (1 to 6) were detected in 31% of the patients. Surgical or endovascular treatment was performed in 54 (76%) patients whereas 17 (24%) had medical management only. Rupture of ICA was fatal in seven (10%) patients. On long-term follow-up 27 (38%) were left with severe disablement. Five patients bled from another aneurysm 2 days to 14 years after initial rupture. Only two of six patients with unruptured aneurysm alone were treated on a prophylactic basis. No clinical marker associated with aneurysm was found. A family history of aneurysm rupture was demonstrated in 10 (18%) kindreds. Linkage to the PKD1 locus was established in two of three tested families.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevention of oxyhemoglobin-induced endothelial and smooth muscle cytoskeletal injury by deferoxamine

The oxidized breakdown products of hemoglobin are important in the pathogenesis of cerebral vasospasm because of their effects on the endothelium and the smooth muscle of the arterial wall. Cytoskeletal changes in cultured vascular cells are sensitive indicators of oxidative injury. Cultured endothelial cells and smooth muscle cells showed a dose-related disruption of the cytoskeleton, particularly the F-actin and vimentin filaments, when exposed to 10(-5) M oxyhemoglobin. The cytoskeletal injury was prevented by the addition of 10(-3) M deferoxamine or 1% albumin. These experiments support a role for deferoxamine in the pharmacological treatment of vasospasm. Furthermore, cytoskeletal studies of cultured arterial endothelial and smooth muscle cells provide a novel in vitro approach by which to study the cellular mechanisms of oxidant injury initiated by the breakdown products of hemoglobin.