Warning leak and management outcome in aneurysmal subarachnoid hemorrhage

Management of intracranial aneurysms: factors that influence clinical grade and surgical outcome

BACKGROUND

We report the experience in managing intracranial aneurysms at our medical center.

METHODS

We retrospectively analyzed 297 intracranial aneurysms managed during a 6-year period. Risk factors were analyzed with respect to their influence on outcome after surgery as measured by Glasgow Outcome Scale score.

RESULTS

Fifty-eight patients had multiple aneurysms. Of all aneurysms, 83% were in the anterior circulation, 37% were unruptured, and 59% were larger than 10 mm in size. Good outcomewas achieved in 75% of patients, and another 16% had fair outcomes. The mortality rate was 4%, and significant morbidity occurred in 5% of patients. Significant indicators of poor outcome were worsened clinical grade, posterior aneurysm location, and large aneurysm size.

CONCLUSION

Hypertensive patients, older patients, and patients with posterior circulation aneurysms had poorer neurologic status, which significantly influenced outcome. Larger aneurysms and vertebrobasilar aneurysms were associated with poor outcomes.

Immediate administration of tranexamic acid and reduced incidence of early rebleeding after aneurysmal subarachnoid hemorrhage: a prospective randomized study

OBJECT

By pursuing a policy of very early aneurysm treatment in neurosurgical centers, in-hospital rebleeds can be virtually eliminated. Nonetheless, as many as 15% of patients with aneurysm rupture suffer ultraearly rebleeding with high mortality rates, and these individuals are beyond the reach of even the most ambitious protocol for diagnosis and referral. Only drugs given immediately after the diagnosis of subarachnoid hemorrhage (SAH) has been established at the local hospital level can, in theory, contribute to the minimization of such ultraearly rebleeding. The object of this randomized, prospective, multicenter study was to assess the efficacy of short-term antifibrinolytic treatment with tranexamic acid in preventing rebleeding.

METHODS

Only patients suffering SAH verified on computerized tomography (CT) scans within 48 hours prior to the first hospital admission were included. A 1-g dose of tranexamic acid was given intravenously as soon as diagnosis of SAH had been verified in the local hospitals (before the patients were transported), followed by doses of 1 g every 6 hours until the aneurysm was occluded; this treatment did not exceed 72 hours. In this study, 254 patients received tranexamic acid and 251 patients were randomized as controls. Age, sex, Hunt and Hess and Fisher grade distributions, as well as aneurysm locations, were congruent between the groups. Outcome was assessed at 6 months post-SAH by using the Glasgow Outcome Scale (GOS). Vasospasm and delayed ischemic neurological deficits were classified according to clinical findings as well as by transcranial Doppler (TCD) studies. All events classified as rebleeding were verified on CT scans or during surgery.

CONCLUSIONS

More than 90% of patients reached the neurosurgical center within 12 hours of their first hospital admission after SAH; 70% of all aneurysms were clipped or coils were inserted within 24 hours of the first hospital admission. Given the protocol, only one rebleed occurred later than 24 hours after the first hospital admission. Despite this strong emphasis on early intervention, however, a cluster of 27 very early rebleeds still occurred in the control group within hours of randomization into the study, and 13 of these patients died. In the tranexamic acid group, six patients rebled and two died. A reduction in the rebleeding rate from 10.8 to 2.4% and an 80% reduction in the mortality rate from early rebleeding with tranexamic acid treatment can therefore be inferred. Favorable outcome according to the GOS increased from 70.5 to 74.8%. According to TCD measurements and clinical findings, there were no indications of increased risk of either ischemic clinical manifestations or vasospasm that could be linked to tranexamic acid treatment. Neurosurgical guidelines for aneurysm rupture should extend also into the preneurosurgical phase to guarantee protection from ultraearly rebleeds. Currently available antifibrinolytic drugs can provide such protection, and at low cost. The number of potentially saved lives exceeds those lost to vasospasm.

Sudden onset headache: a prospective study of features, incidence and causes

Sudden onset headache is a common condition that sometimes indicates a life-threatening subarachnoid haemorrhage (SAH) but is mostly harmless. We have performed a prospective study of 137 consecutive patients with this kind of headache (thunderclap headache=TCH). The examination included a CT scan, CSF examination and follow-up of patients with no SAH during the period between 2 days and 12 months after the headache attack. The incidence was 43 per 100 000 inhabitants >18 years of age per year; 11.3% of the patients with TCH had SAH. Findings in other patients indicated cerebral infarction (five), intracerebral haematoma (three), aseptic meningitis (four), cerebral oedema (one) and sinus thrombosis (one). Thus no specific finding indicating the underlying cause of the TCH attack was found in the majority of the patients. A slightly increased prevalence of migraine was found in the non-SAH patients (28%). The attacks occurred in 11 cases (8%) during sexual activity and two of these had an SAH. Nausea, neck stiffness, occipital location and impaired consciousness were significantly more frequent with SAH but did not occur in all cases. Location in the temporal region and pressing headache quality were the only features that were more common in non-SAH patients. Recurrent attacks of TCH occurred in 24% of the non-SAH patients. No SAH occurred later in this group, nor in any of the other patients. It was concluded that attacks caused by a SAH cannot be distinguished from non-SAH attacks on clinical grounds. It is important that patients with their first TCH attack are investigated with CT and CSF examination to exclude SAH, meningitis or cerebral infarction. The results from this and previous studies indicate that it is not necessary to perform angiography in patients with a TCH attack, provided that no symptoms or signs indicate a possible brain lesion and a CT scan and CSF examination have not indicated SAH.

Association of apolipoprotein E polymorphism with outcome after aneurysmal subarachnoid hemorrhage: a preliminary study

BACKGROUND AND PURPOSE

Variation in the outcome after aneurysmal subarachnoid hemorrhage (SAH) is not fully explained by known prognostic factors. APOE genotype is the most important genetic determinant of susceptibility to Alzheimer's disease, and it is also shown to be associated with the outcome after traumatic brain injury. We studied the association of apolipoprotein E polymorphism with the outcome after aneurysmal SAH.

METHODS

A total of 160 consecutive patients were admitted after SAH to a neurosurgical unit. The clinical assessment after the SAH was performed with the Hunt and Hess grading scale. The severity of the bleeding as visualized on CT was assessed by Fisher's grading system. Outcome was assessed with the Glasgow Outcome SCALE: APOE genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

126 patients had aneurysmatic SAH, and detailed information on outcome and APOE genotype was available for 108 patients (86%). Sixteen (40%) of 40 patients with APOE epsilon4 had an unfavorable outcome compared with 13 (19%) of 68 without the APOE epsilon4 allele (OR 2.8, 95% CI 1.18 to 6.77). Association was more significant after adjustment for age, rebleeding, clinical status on admission, and CT scan findings (OR 7.1, 95% CI 1.9 to 26.3; P=0.0035).

CONCLUSIONS

Our findings show a significant genetic association of APOE polymorphism with outcome after spontaneous aneurysmal SAH. Genetic factors thus seem to explain a part of individual differences in the recovery of SAH.

Acute and delayed vasoconstriction after subarachnoid hemorrhage: local cerebral blood flow, histopathology, and morphology in the rat basilar artery

The decreased local cerebral blood flow (LCBF) and cerebral ischemia that occur after subarachnoid hemorrhage (SAH) may be caused by acute and/or delayed vasospasm. In 36 Sprague-Dawley (350-450 g) rats SAH was induced by transclival puncture of the basilar artery. Mean arterial blood pressure (MABP), LCBF, intracranial pressure (ICP), and cerebral perfusion pressure (CPP) were measured in all rats for 30 min before and 60 min after SAH was induced. One set of control (n : 7) and experimental animals (n : 7) was sacrificed after the 60 min of initial post-hemorrhage measurements were recorded. Four days after SAH induction, LCBF and MABP were measured again for 60 min in subgroups of surviving experimental rats (n : 7) and control rats (n : 7). Histopathologic and morphologic examinations of the basilar artery were performed in each subgroup. There was a sharp drop in LCBF just after SAH was induced (55.50 +/- 11.46 mlLD/min/100 g and 16.1 +/- 3.6 mlLD/min/100 g for baseline and post-SAH, respectively; p < 0.001). The flow then gradually increased but had not returned to pre-SAH values by 60 min (p < 0.05). At 4 days after SAH induction, although LCBF was lower than that observed in the control group and pre-SAH values, it was not significantly different from either of these flow rates (p > 0.05). ICP (baseline 7.05 +/- 0.4 mmHg) increased acutely to 75.2 +/- 7.1 mmHg, but returned to normal levels by 60 min after SAH. CPP (baseline 84.5 +/- 6.3 mmHg) dropped accordingly (to 18.6 +/- 3.1 mmHg), and then increased, reaching 72.2 +/- 4.9 mmHg at 60 min after SAH (p > 0.05). Examinations of the arteries revealed decreased inner luminal diameter and distortion of the elastica layer in the early stage. LCBF in nonsurviver rats (n : 8) was lower than that in the animals that survived (p < 0.01). At 4 days post-hemorrhage, the rats' basilar arteries showed marked vasculopathy. The findings showed that acute SAH alters LCBF, ICP, and CPP, and that decreased LCBF affects mortality rate. Subsequent vasculopathy occurs in delayed fashion, and this was observed at 4 days after the hemorrhage event.

Estimate of the maximum time interval between formation of cerebral aneurysm and rupture

The recent publication of the results of the international study on unruptured intracranial aneurysms highlighted a paradox: there do not seem to be enough unruptured aneurysms in the population to account for the observed incidence of subarachnoid haemorrhage. Some authors have suggested that the answer to this paradox is that most aneurysms that bleed do so shortly after formation. This would mean that the bulk of subarachnoid haemorrhages come from recently formed rather than long standing aneurysms. This paradox and proposed answer are examined. The available statistics on the incidence of subarachnoid haemorrhage, the prevalence of unruptured aneurysms, and the risk of bleeding from unruptured aneurysms are used to place a maximum on the time interval between aneurysm formation and rupture. For aneurysms less than 10 mm in diameter in persons with no history of subarachnoid haemorrhage, an estimate of less than 42 weeks was made. The null hypothesis that such aneurysms pose a constant risk with time is rejected with p <10(-9). In larger aneurysms the risk seems to be constant with time.

Subarachnoid haemorrhage: epidemiology, risk factors, and treatment options

The present review focuses on subarachnoid haemorrhage (SAH) secondary to the rupture of an intracranial aneurysm, a condition with a high case fatality rate. Additionally, many of the surviving patients are left with significant disabilities. Risk factors for aneurysmal SAH include both genetic and acquired conditions. The most common presenting symptom is sudden onset of severe headache. Since headache is very common in the general population, it is not unusual that SAH is misdiagnosed at its onset with often catastrophic consequences. Unlike other acute neurological disorders such as brain injury, in which patient outcome is closely related to the extent of the injury occurring at the time of the trauma, patients with aneurysmal SAH are at risk of subsequent deterioration from 'avoidable' complications such as rebleed, vasospasm, hydrocephalus, and several other non-neurological general medical complications. Thus, the critical care management of the patient with SAH is of utmost importance in order to maximise the chances of satisfactory recovery. Although surgical clipping of the ruptured aneurysm remains the gold standard therapy, with the continuing refinement of endovascular techniques, a new, 'less invasive' option is now available, especially for patients considered poor surgical candidates.

The notion of "warning leaks" in subarachnoid haemorrhage: are such patients in fact admitted with a rebleed?

OBJECTIVE

Often patients with subarachnoid haemorrhage (SAH) recall a recent episode of acute severe headache, usually interpreted as a "warning headache" or first SAH. An alternative explanation is recall bias. The clinical and radiological features of patients with SAH were studied in relation to previous headaches or later rebleeding.

METHODS

Patients with either a previous headache episode or a subsequent rebleed were selected from the SAH database in Utrecht within 1 month of the index SAH. The clinical condition was graded on the World Federation of Neurological Surgeons (WFNS) scale. The CT was reviewed and the amounts of subarachnoid blood, hydrocephalus, and intraventricular, intracerebral, and subdural blood were rated. Proportions were compared by unpaired or paired t test.

RESULTS

Forty four of 390 patients (11%) had had a severe headache before their index SAH (11 of these had a subsequent rebleed); 31 other patients had a rebleed in hospital but no preceding headache. Patients with and without preceding headache did not differ in level of consciousness (14 of 44 v 11 of 31 were comatose), nor in any of the radiological features. After rebleeding (42 patients), 37 of 42 patients were comatose (v 11 of 42 before), and CT showed higher proportions of intracerebral haemorrhage (17%), intraventricular haemorrhage, (27%), and hydrocephalus (12%) than baseline scans. Intraventricular haemorrhage was twice as frequent after rebleeding than at baseline.

CONCLUSIONS

The clinical and radiological features of patients admitted with SAH after a preceding bout of headache did not differ from those without such an episode, and are clearly dissimilar from those after documented rebleeds. The findings challenge the existence of minor "warning headaches".

Unruptured cerebral aneurysm producing a thunderclap headache

A sudden and severe headache is the most common presentation of an acutely ruptured cerebral aneurysm. A similar headache in the absence of subarachnoid blood has rarely been ascribed to an unruptured cerebral aneurysm, but may result from acute aneurysm expansion and indicate a high risk of future rupture. We present a patient who developed a sudden, severe, "thunderclap" headache, with no associated neurological deficit. Computed tomogram and lumbar cerebral spinal fluid obtained 5.5 hours after headache onset were negative for subarachnoid hemorrhage. The patient underwent cerebral angiography which revealed a posterior communicating artery aneurysm with an associated daughter aneurysm. Craniotomy and clip obliteration of the aneurysm were performed. The aneurysm dome was very thin and there was no evidence of recent or old hemorrhage. A "thunderclap" headache without subarachnoid hemorrhage may be an important harbinger of a cerebral aneurysm with the potential for future rupture. Early recognition and neurovascular imaging of aneurysms presenting in this rare fashion are warranted.

Prognostic value and determinants of ultraearly angiographic vasospasm after aneurysmal subarachnoid hemorrhage

OBJECTIVE

A small number of patients with aneurysmal subarachnoid hemorrhage have angiographic evidence of cerebral vasospasm within 48 hours of the onset of hemorrhage. The present study analyzes the prognostic value and determinants of this ultraearly angiographic finding.

METHODS

We analyzed prospectively collected data from the placebo-treated group in a multicenter clinical trial conducted at 54 neurosurgical centers in North America. The presence and severity of ultraearly angiographic vasospasm (UEAV) was determined by a blinded review of the admission angiograms. Using logistic regression analysis, we identified independent determinants of UEAV from demographic, clinical, laboratory, and neuroimaging characteristics of the patients. The impact of UEAV on the risk of symptomatic vasospasm and 3-month outcome was analyzed after adjusting for potential confounding factors.

RESULTS

Of 296 patients in the analysis, 37 (13%) had angiographic evidence of vasospasm at admission. An initial Glasgow Coma Scale score of less than 14 (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.1-6.0), and serum sodium greater than 138 mmol/L (OR, 3.4; 95% CI, 1.5-8.3) were associated with UEAV. UEAV was associated with increased risk of symptomatic vasospasm (OR, 2.5; 95% CI, 1.2-5.4) and poor outcome at 3 months (OR, 2.8; 95% CI, 1.2-6.3), after adjusting for other variables. This risk of symptomatic vasospasm was not influenced by early surgery (within 48 h of hemorrhage onset). Poor outcome was more likely to occur in patients with UEAV who did not undergo early surgery (P = 0.03).

CONCLUSION

Our analysis suggests that patients with angiographic evidence of vasospasm at admission are at high risk for both symptomatic vasospasm and poor outcome. We also found that early surgery did not aggravate this risk.