Hemorheological and hemodynamic analysis of hypervolemic hemodilution therapy for cerebral vasospasm after aneurysmal subarachnoid hemorrhage

Liberal versus restrictive transfusion strategies in subarachnoid hemorrhage: a secondary analysis of the TRAIN study

BACKGROUND

The optimal hemoglobin (Hb) threshold to trigger red blood cell transfusions (RBCT) in subarachnoid hemorrhage (SAH) patients is unclear. This study evaluated the impact of liberal versus restrictive transfusion strategies on neurological outcome in patients with SAH.

METHODS

This is a pre-planned secondary analysis of the "TRansfusion Strategies in Acute brain INjured Patients" (TRAIN) study. We included all SAH patients from the original study that were randomized to receive RBCT when Hb levels dropped below 9 g/dL (liberal group) or 7 g/dL (restrictive group). The primary outcome was an unfavorable neurological outcome at 180 days, defined by a Glasgow Outcome Scale Extended score of 1-5.

RESULTS

Of the 190 SAH patients in the trial, 188 (98.9%) had data available for the primary outcome, with 86 (45.3%) in the liberal group and 102 (53.6%) in the restrictive group. Patients in the liberal group were older than in the restrictive group, but otherwise had similar baseline characteristics. Patients in the liberal group received more RBCT and showed higher Hb levels over time. At 180 days, 57 (66.3%) patients in the liberal group and 78 (76.4%) in the restrictive group had unfavorable outcomes (risk ratio, RR 0.87; 95% confidence intervals, 95% CI 0.71-1.04). Patients in the liberal group had a significantly lower risk of cerebral ischemia (RR 0.63; 95% CI 0.41-0.97). In a multivariate analysis, randomization to the liberal group was associated with a lower risk of unfavorable outcome (RR 0.83, 95% CI 0.70-0.99).

CONCLUSIONS

A liberal transfusion strategy was not associated with a lower incidence of unfavorable outcome after SAH when compared to a restrictive strategy. However, in a multivariable analysis adjusted for confounders randomization to the liberal group was associated with lower risk of unfavorable outcome. The occurrence of cerebral ischemia was significantly lower in the liberal transfusion strategy group.

TRIAL REGISTRATION

ClinicalTrials.gov number-NCT02968654 registered on November 16th, 2016.

The Benefits and Feasibility of External Lumbar Cerebrospinal Fluid Drainage for Cerebral Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage: Meta-Analysis and Trial Sequential Analysis

OBJECTIVE

Cerebral vasospasm after aneurysmal subarachnoid hemorrhage is a main cause contributing to poor outcomes. Removal of blood from the subarachnoid may decrease development of cerebral vasospasm. The purpose of this study is to determine the effect of lumbar cerebrospinal fluid (CSF) drainage on cerebral vasospasm and related complications through meta-analysis and trial sequential analysis (TSA).

METHODS

A systematic search of the literature was performed. Case-control studies of the effects of external lumbar drainage in patients with subarachnoid hemorrhage were included. The association between lumbar drain and vasospasm, cerebral infarction, subsequent treatment, and mortality were evaluated.

RESULTS

Eleven of 122 articles were included in the meta-analysis. Lumbar CSF drainage reduces occurrence of vasospasm and related complications. In meta-analysis, the pooled odds ratio for symptomatic vasospasm, cerebral infarct, endovascular treatment for vasospasm, and mortality was 0.40 (95% confidence interval [CI], 0.31-0.51; P = 0.00001), 0.47 (95% CI, 0.35-0.62; P < 0.0001), 0.29 (95% CI, 0.18-0.46; P < 0.0001), and 0.41, (95% CI, 0.23-0.74; P = 0.003), respectively, compared with the non-lumbar drainage group. In TSA, the cumulative Z line crossed α-spending boundaries and reached the required sample size in analysis of symptomatic vasospasm and endovascular treatment for vasospasm.

CONCLUSIONS

Lumbar CSF drainage can decrease symptomatic vasospasm, cerebral infarction, subsequent endovascular treatment, and mortality. Through TSA, the accuracy and reliability of the effect of lumbar CSF drainage-related cerebral vasospasm and endovascular treatment are increased. Further studies of the association between lumbar drain and cerebral infarction and mortality are required to confirm the generalization of the results.

Elevated hemoglobin is associated with poor prognosis in Tibetans with poor-grade aneurysmal subarachnoid hemorrhage after clipping: A Retrospective Case-Control Study

OBJECTIVES

High hemoglobin (HGB) concentration is frequently seen in Tibetans in clinical practice; however, the impact on postsurgical prognosis in patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH) is not precisely known. Thus, we sought to understand the association between high HGB level and postoperative outcome in Tibetans with poor-grade aSAH.

PATIENTS AND METHODS

Results of clipping in consecutive Tibetan patients with poor-grade aSAH were analyzed retrospectively for the period January 2012 to January 2017. Based on the upper limit (160g/L) of normal hemoglobin levels, patients were divided to a high (HHC) and a normal (NHC) HGB-level cohort according to the first routine blood result on admission. Propensity score matching was used for baseline matching in the 2 cohorts. Postoperative complications in the 2 groups were compared. Prognosis after ictus, including 6-month neurological functional status and mortality at 30 days and 6 months were also assessed.

RESULTS

Risk of ischemia, pulmonary embolism and lower-limb deep venous thrombosis (DVT) was higher in HHC than NHC (62.88% vs. 21.64%; P<0.001; 10.30% vs. 1.31%, P<0.005; 24.74% vs. 7.21%, P<0.001, respectively). Hospital stay also differed significantly (15.82±3.86 vs. 10.37±4.80 days; P<0.001). Out of the 194 patients, 150 survived at 6 months. At 6-month neurological functional follow-up, 8 NHC patients had favorable modified Rankin scale (mRS) scores ≤2 at discharge, versus only 1 HHC patient, showing better outcome in NHC than HHC (8.25% vs. 1.03%; P=0.035). In-hospital mortality was significantly greater in HHC than NHC (17.52% vs. 7.22%; P=0.029). 30-day post-ictus mortality was 30.93% in HHC versus 14.43% in NHC (P<0.006). There was also a significant difference in mortality at 6 months post-ictus (47.42% vs. 18.56%; P<0.001).

CONCLUSION

High HGB level was associated with increased risk of postsurgical cerebral ischemia, pulmonary embolism and lower-limb DVT and poor prognosis in poor-grade aSAH patients. Preoperative hemodilution therapy might be beneficial in reducing operative complications, reducing hospital stay and improving short-term prognosis for neurological functional recovery in aSAH patients with high HGB concentration, but further detailed research is needed.

A Mechanistic Analysis of Possible Blood Transfusion Failure to Increase Circulatory Oxygen Delivery in Anemic Patients

The effects of changing hematocrit (Hct) on the rate of circulatory oxygen ([Formula: see text]) delivery were modeled analytically to describe transfusion of 0.5-3.0 units of packed red blood cells (pRBC, 300 mL/unit, 60% Hct) to anemic patients. In our model, Hct affects [Formula: see text] delivery to the microcirculation by changing blood [Formula: see text] carrying capacity and blood viscosity, which in turn affects blood flow velocity and, therefore, [Formula: see text] delivery. Changing blood velocity impacts the [Formula: see text] delivery by affecting the oxygen diffusive losses as blood transits through the arteriolar vasculature. An increase in Hct has two opposite effects: it increases the blood [Formula: see text] carrying capacity and decreases the flow velocity. This suggests the existence of an optimal Hct that maximizes [Formula: see text] delivery. Our results show that maximal [Formula: see text] delivery occurs in the anemic range, where [Formula: see text]%. Optimal blood management is associated with transfusing enough units up to reaching maximal [Formula: see text] delivery. Although somewhat complex to implement, this practice would result in both substantial blood savings and improved [Formula: see text] delivery.

Advanced monitoring of systemic hemodynamics in critically ill patients with acute brain injury

Hemodynamic monitoring is widely used in critical care; however, the impact of such intervention in patients with acute brain injury (ABI) remains unclear. Using PubMed, a systematic review was performed (1966-August 2013), and 118 studies were included. Data were extracted using the PICO approach. The evidence was classified, and recommendations were developed according to the GRADE system. Electrocardiography and invasive monitoring of arterial blood pressure should be the minimal hemodynamic monitoring required in unstable or at-risk patients in the intensive care unit. Advanced hemodynamic monitoring (i.e., assessment of preload, afterload, cardiac output, and global systemic perfusion) could help establish goals that take into account cerebral blood flow and oxygenation, which vary depending on diagnosis and disease stage. Choice of techniques for assessing preload, afterload, cardiac output, and global systemic perfusion should be guided by specific evidence and local expertise. Hemodynamic monitoring is important and has specific indications among ABI patients. Further data are necessary to understand its potential for therapeutic interventions and prognostication.

The effectiveness of lumbar cerebrospinal fluid drainage to reduce the cerebral vasospasm after surgical clipping for aneurysmal subarachnoid hemorrhage

Objective

Removal of blood from subarachnoid space with a lumbar drainage (LD) may decrease development of cerebral vasospasm. We evaluated the effectiveness of a LD for a clinical vasospasm and outcomes after clipping of aneurysmal subarachnoid hemorrhage (SAH).

Methods

Between July 2008 and July 2013, 234 patients were included in this study. The LD group consisted of 126 patients, 108 patients in the non LD group. We investigated outcomes as follow : 1) clinical vasospasm, 2) angioplasty, 3) cerebral infarction, 4) Glasgow outcome scale (GOS) score at discharge, 5) GOS score at 6-month follow-up, and 6) mortality.

Results

Clinical vasospasm occurred in 19% of the LD group and 42% of the non LD group (p<0.001). Angioplasty was performed in 17% of the LD group and 38% of the non LD group (p=0.001). Cerebral infarctions were detected in 29% and 54% of each group respectively (p<0.001). The proportion of GOS score 5 at 6 month follow-up in the LD group was 69%, and it was 58% in the non LD group (p=0.001). Mortality rate showed 5% and 10% in each group respectively. But, there was no difference in shunt between the two groups.

Conclusion

LD after aneurysmal SAH shows marked reduction of clinical vasospasm and need for angioplasty. With this technique we have shown favorable GOS score at 6 month follow-up.

Pharmacologic Management of Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) remains a condition with suboptimal functional outcomes, especially in the young population. Pharmacotherapy has an accepted role in several aspects of the disease and an emerging role in several others. No preventive pharmacologic interventions for SAH currently exist. Antiplatelet medications as well as anticoagulation have been used to prevent thromboembolic events after endovascular coiling. However, the main focus of pharmacologic treatment of SAH is the prevention of delayed cerebral ischemia (DCI). Currently the only evidence-based medical intervention is nimodipine. Other calcium channel blockers have been evaluated without convincing efficacy. Anti-inflammatory drugs such as statins have demonstrated early potential; however, they failed to provide significant evidence for the use in preventing DCI. Similar findings have been reported for magnesium, which showed potential in experimental studies and a phase 2 trial. Clazosentane, a potent endothelin receptor antagonist, did not translate to improve functional outcomes. Various other neuroprotective agents have been used to prevent DCI; however, the results have been, at best inconclusive. The prevention of DCI and improvement in functional outcome remain the goals of pharmacotherapy after the culprit lesion has been treated in aneurysmal SAH. Therefore, further research to elucidate the exact mechanisms by which DCI is propagated is clearly needed. In this article, we review the current pharmacologic approaches that have been evaluated in SAH and highlight the areas in which further research is needed.

Cerebral Vasospasm in Critically III Patients with Aneurysmal Subarachnoid Hemorrhage: Does the Evidence Support the Ever-Growing List of Potential Pharmacotherapy Interventions?

The occurrence of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) is a significant event resulting in decreased cerebral blood flow and oxygen delivery. Prevention and treatment of cerebral vasospasm is vital to avert neurological damage and reduced functional outcomes. A variety of pharmacotherapy interventions for the prevention and treatment of cerebral vasospasm have been evaluated. Unfortunately, very few large randomized trials exist to date, making it difficult to make clear recommendations regarding the efficacy and safety of most pharmacologic interventions. Considerable debate exists regarding the efficacy and safety of hypervolemia, hemodilution, and hypertension (triple-H therapy), and the implementation of each component varies substantially amongst institutions. There is a new focus on euvolemic-induced hypertension as a potentially preferred mechanism of hemodynamic augmentation. Nimodipine is the one pharmacologic intervention that has demonstrated favorable effects on patient outcomes and should be routinely administered unless contraindications are present. Intravenous nicardipine may offer an alternative to oral nimodipine. The addition of high-dose magnesium or statin therapy has shown promise, but results of ongoing large prospective studies are needed before they can be routinely recommended. Tirilazad and clazosentan offer new pharmacologic mechanisms, but clinical outcome results from prospective randomized studies have largely been unfavorable. Locally administered pharmacotherapy provides a targeted approach to the treatment of cerebral vasospasm. However, the paucity of data makes it challenging to determine the most appropriate therapy and implementation strategy. Further studies are needed for most pharmacologic therapies to determine whether meaningful efficacy exists.

Current controversies in the prediction, diagnosis, and management of cerebral vasospasm: where do we stand?

Aneurysmal subarachnoid hemorrhage occurs in approximately 30,000 persons in the United States each year. Around 30 percent of patients with aneurysmal subarachnoid hemorrhage suffer from cerebral ischemia and infarction due to cerebral vasospasm, a leading cause of treatable death and disability following aneurysmal subarachnoid hemorrhage. Methods used to predict, diagnose, and manage vasospasm are the topic of recent active research. This paper utilizes a comprehensive review of the recent literature to address controversies surrounding these topics. Evidence regarding the effect of age, smoking, and cocaine use on the incidence and outcome of vasospasm is reviewed. The abilities of different computed tomography grading schemes to predict vasospasm in the aftermath of subarachnoid hemorrhage are presented. Additionally, the utility of different diagnostic methods for the detection and visualization of vasospasm, including transcranial Doppler ultrasonography, CT angiography, digital subtraction angiography, and CT perfusion imaging is discussed. Finally, the recent literature regarding interventions for the prophylaxis and treatment of vasospasm, including hyperdynamic therapy, albumin, calcium channel agonists, statins, magnesium sulfate, and endothelin antagonists is summarized. Recent studies regarding each topic were reviewed for consensus recommendations from the literature, which were then presented.

Update on the management of subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease. Outcome after SAH is mainly determined by the initial severity of the hemorrhage. Neuroimaging, in particular computed tomography, and aneurysm repair techniques, such as coiling and clipping, as well as neurocritical care management, have improved during the last few years. The management of a patient with SAH should have an interdisciplinary approach with case discussions between the neurointensivist, interventionalist and the neurosurgeon. The patient should be treated in a specialized neurointensive care unit of a center with sufficient SAH case volume. Poor-grade patients can be observed for complications and delayed cerebral ischemia through continuous monitoring techniques in addition to transcranial Doppler ultrasonography such as continuous electroencephalography, brain tissue oxygenation, cerebral metabolism, cerebral blood flow and serial vascular imaging. Neurocritical care should focus on neuromonitoring for delayed cerebral ischemia, management of hydrocephalus, seizures and intracranial hypertension, as well as of medical complications such as hyperglycemia, fever and anemia.

The association between fluid balance and outcomes after subarachnoid hemorrhage

BACKGROUND

We sought to determine the association between early fluid balance and neurological/vital outcome of patients with subarachnoid hemorrhage.

METHODS

Hospital admission, imaging, ICU and outcome data were retrospectively collected from the medical records of adult patients with aneurysmal SAH admitted to a level-1 trauma and stroke referral center during a 5-year period. Two groups were identified based on cumulative fluid balance by ICU day 3: (i) patients with a positive fluid balance (n = 221) and (ii) patients with even or negative fluid balance (n = 135). Multivariable logistic regression was used to adjust for age, Hunt-Hess and Fisher scores, mechanical ventilation and troponin elevation (>0.40 ng/ml) at ICU admission. The primary outcome was a composite of hospital mortality or new stroke.

RESULTS

Patients with positive fluid balance had worse admission GCS and Hunt-Hess score, and by ICU day 3 had cumulatively received more IV fluids, but had less urine output when compared with the negative fluid balance group. There was no difference in the odds of hospital death or new stroke (adjusted OR: 1.47, 95%CI: 0.85, 2.54) between patients with positive and negative fluid balance. However, positive fluid balance was associated with increased odds of TCD vasospasm (adjusted OR 2.25, 95%CI: 1.37, 3.71) and prolonged hospital length of stay.

CONCLUSIONS

Although handling of IV fluid administration was not an independent predictor of mortality or new stroke, patients with early positive fluid balance had worse clinical presentation and had greater resource use during the hospital course.

Hemodynamic management of subarachnoid hemorrhage

Hemodynamic augmentation therapy is considered standard treatment to help prevent and treat vasospasm and delayed cerebral ischemia. Standard triple-H therapy combines volume expansion (hypervolemia), blood pressure augmentation (hypertension), and hemodilution. An electronic literature search was conducted of English-language papers published between 2000 and October 2010 that focused on hemodynamic augmentation therapies in patients with subarachnoid hemorrhage. Among the eligible reports identified, 11 addressed volume expansion, 10 blood pressure management, 4 inotropic therapy, and 12 hemodynamic augmentation in patients with unsecured aneurysms. While hypovolemia should be avoided, hypervolemia did not appear to confer additional benefits over normovolemic therapy, with an excess of side effects occurring in patients treated with hypervolemic targets. Overall, hypertension was associated with higher cerebral blood flow, regardless of volume status (normo- or hypervolemia), with neurological symptom reversal seen in two-thirds of treated patients. Limited data were available for evaluating inotropic agents or hemodynamic augmentation in patients with additional unsecured aneurysms. In the context of sparse data, no incremental risk of aneurysmal rupture has been reported with the induction of hemodynamic augmentation.

The evolving role of hemodilution in treatment of cerebral vasospasm: a historical perspective

OBJECTIVE

Hypertension, hypervolemia, and hemodilution [HHH] therapy is widely used for prophylactic and therapeutic means in the setting of angiographic or clinical cerebral vasospasm. Hemodilution remains the most controversial aspect of the HHH therapy.

METHODS

We performed a literature review to identify the current state of support for hemodilution as a therapeutic modality in treatment of cerebral vasospasm.

RESULTS

Over time, evidence has been accumulating against the efficacy of HHH therapy and hemodilution in particular. Although HHH therapy and consequently hemodilution has wide support, the evidence for its effectiveness remains equivocal.

CONCLUSIONS

At the time of this study, the burden of evidence appears to be tipped away from hemodilution as a therapeutic modality.

Multichannel near-infrared spectroscopy as a tool for assisting intra-arterial fasudil therapy for diffuse vasospasm after subarachnoid hemorrhage

BACKGROUND

Diffuse cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) refractory to medical management can be treated with intra-arterial administration of vasodilators, but valid bedside monitoring for the diagnosis and therapeutic assessment is poorly available. We demonstrate the successful application of regional cerebral oxygen saturation (rSO(2)) monitoring with multichannel near-infrared spectroscopy (NIRS) in assisting intra-arterial infusions of fasudil hydrochloride to a patient suffering from post-SAH vasospasm in the distal vascular territories.

CASE DESCRIPTION

A 63-year-old man presented with SAH and intracerebral hematoma due to ruptured right middle cerebral artery aneurysm developed aphasia and right-sided weakness on day 9 after SAH onset. Delayed cerebral ischemia attributable to diffuse vasospasm in the distal territories of the left anterior and middle cerebral arteries was suspected. Since the symptoms persisted despite maximal hyperdynamic therapy with dobutamine, intra-arterial fasudil treatment in the setting of rSO(2) monitoring including the spasm-affected vascular territory with four-channel flexible NIRS sensors was subsequently performed. Decreased and fluctuating rSO(2) in angiographically documented vasospastic territories increased immediately after intra-arterial fasudil infusion in accordance with relief of vasospasm that correlated with neurological improvement. The procedure was repeated on day 11 since the effect was transient and neurological deterioration and reduction of rSO(2) recurred. The deficits resolved accompanied by uptake and maintenance of rSO (2) following the intra-arterial fasudil, resulting in favorable functional outcome.

CONCLUSION

Continuous rSO(2) monitoring with multichannel NIRS is a feasible strategy to assist intraarterial fasudil therapy for detecting and treating the focal ischemic area exposed to diffuse vasospasm.

Effects of infusion of different fluids during controlled hypotension on gastric intramucosal pH and postoperative gastroenterological function

The present study was aimed to investigate the effects of infusion of different fluids combined with controlled hypotension on gastric intramucosal pH (pHi) and postoperative gastrointestinal function in patients undergoing hepatocarcinoma surgery. Forty-five patients (ASA II) scheduled for surgical resection of hepatocarcinoma undergoing controlled hypotension were randomly assigned to three groups and received infusion of 20 mL/kg Ringer's solution (R group), 6% HAES(H group) or 6% Voluven group (W group). Intragastric PgCO2, pHi, hematocrit and hemoglobin were measured. The significant decrease of pHi and increase of PgCO2 were produced at 1 and 2 h after controlled hypotension in the R group (P < 0.05 or P < 0.01). The time of bowel movement after operation was shorter in the W group than the R group. Meanwhile, we also did not find obvious difference in blood gas indexes among the three groups. The infusion of HAES and Voluven during controlled hypotension could improve gastrointestinal perfusion and accelerate the recovery of postoperative gastrointestinal function.

A review of delayed ischemic neurologic deficit following aneurysmal subarachnoid hemorrhage: historical overview, current treatment, and pathophysiology

Delayed ischemic neurologic deficit (DIND) is a serious and poorly understood complication of aneurysmal subarachnoid hemorrhage. Although advances in treatment have improved prognosis for these patients, long-term clinical outcomes remain disappointing. Historically, angiographic vasospasm was thought to result in a DIND, although an increasing body of evidence suggests that this is an oversimplification, because interventions that have effectively targeted angiographic vasospasm have not improved outcome. Consequently, the relationship between angiographic vasospasm and neurologic outcome may be associative rather than causative. Although our understanding of the underlying molecular processes and pathophysiology is improving, responsible mediators or pathways have yet to be identified. The aim of this review is to summarize the key historical events that have helped shape our understanding of the pathophysiology of this phenomenon (microcirculation, autoregulation, microthrombosis, inflammation, apoptosis, spreading depolarization, oxidative stress) and to present the evidence underlying current treatment strategies (hemodynamic therapy, oral nimodipine, endovascular therapy, statins, cerebrospinal fluid drainage, thrombolysis, magnesium) and the translational and clinical research investigating DIND.

Inferior vena cava distensibility as a predictor of fluid responsiveness in patients with subarachnoid hemorrhage

BACKGROUND

The objective of our study is to assess the reliability of the distensibility of the inferior vena cava (dIVC), as measured by ultrasound, as an indicator of fluid responsiveness in patients with subarachnoid hemorrhage.

METHODS

We enrolled 29 adult patients requiring advanced hemodynamic monitoring, sedation, and mechanical ventilation. Inferior vena cava diameter was measured during a single mechanical breath. The dIVC was calculated as (the diameter of the inferior vena cava on inspiration-the diameter on expiration)/the diameter on expiration. All the hemodynamic parameters were collected at baseline and after a fluid challenge (7 ml/kg) with 6% hydroxyethyl starch. A 15% increase of cardiac index was the standard criterion used to differentiate patients with and without a response to fluid therapy.

RESULTS

Apart from stroke volume variation (SVV) and dIVC, which were significantly higher in fluid responders (17 patients), the other baseline characteristics did not differ significantly between groups (responders versus non-responders). Significant changes in hemodynamic parameters after volume load were observed only in fluid responders. The area under the ROC curve was 0.779 (95% confidence interval 0.587-0.911) for SVV and 0.902 (95% confidence interval 0.733-0.979, P = NS) for dIVC. Central venous pressure was a less reliable indicator of fluid responsiveness than dIVC. A dIVC value of >16% yielded the most favorable balance of test characteristics, with 70.59% sensitivity and 100% specificity. There was a trend toward a lower incidence of delayed ischemic lesions in fluid responders (11.7 vs. 25%, P = NS).

CONCLUSION

dIVC proved to be a reliable predictor of fluid responsiveness in ICU patients with subarachnoid hemorrhage.

Effect of different components of triple-H therapy on cerebral perfusion in patients with aneurysmal subarachnoid haemorrhage: a systematic review

Introduction

Triple-H therapy and its separate components (hypervolemia, hemodilution, and hypertension) aim to increase cerebral perfusion in subarachnoid haemorrhage (SAH) patients with delayed cerebral ischemia. We systematically reviewed the literature on the effect of triple-H components on cerebral perfusion in SAH patients.

Methods

We searched medical databases to identify all articles until October 2009 (except case reports) on treatment with triple-H components in SAH patients with evaluation of the treatment using cerebral blood flow (CBF in ml/100 g/min) measurement. We summarized study design, patient and intervention characteristics, and calculated differences in mean CBF before and after intervention.

Results

Eleven studies (4 to 51 patients per study) were included (one randomized trial). Hemodilution did not change CBF. One of seven studies on hypervolemia showed statistically significant CBF increase compared to baseline; there was no comparable control group. Two of four studies applying hypertension and one of two applying triple-H showed significant CBF increase, none used a control group. The large heterogeneity in interventions and study populations prohibited meta-analyses.

Conclusions

There is no good evidence from controlled studies for a positive effect of triple-H or its separate components on CBF in SAH patients. In uncontrolled studies, hypertension seems to be more effective in increasing CBF than hemodilution or hypervolemia.

Which H is the most important in triple-H therapy for cerebral vasospasm?

PURPOSE OF REVIEW

To summarize the recent literature of the hemodynamic management of subarachnoid hemorrhage and cerebral vasospasm, also designated as 'triple-H' therapy, and discuss each component of this management approach individually.

RECENT FINDINGS

Following the publication of a review on circulatory volume expansion in the Cochrane Registry database in 2004 and a meta-analysis in 2003, there are no new randomized trials of triple-H therapy to prevent or treat cerebral vasospasm. However, physiological studies have been reported that contribute to the understanding of some of the components of triple-H therapy.

SUMMARY

There remains a paucity of information regarding the efficacy and safety of triple-H therapy. The complexity in exploring this topic derives not only from the interdependence of the different components of triple-H therapy but also by the limitation in the assessment of hemodynamic variables. However, there is some emerging physiologic data suggesting that normovolemic hypertension may be the component most likely to increase cerebral blood flow after subarachnoid hemorrhage. In contrast, hypervolemic hemodilution is associated with increased complications and might also lower the hemoglobin to excessively low levels.

B-type natriuretic peptide release and left ventricular filling pressure assessed by echocardiographic study after subarachnoid hemorrhage: a prospective study in non-cardiac patients

INTRODUCTION

Serum B-type natriuretic peptide (BNP) is frequently elevated after subarachnoid hemorrhage (SAH), but whether this high BNP level is related to transient elevation of left ventricular filling pressure (LVFP) is unknown. However, in patients with preexistent cardiac pathologies, it is impossible to differentiate between BNP elevation caused by chronic cardiac abnormalities and BNP related to acute neurocardiac injury.

METHODS

All adult patients with SAH admitted to our intensive care unit were eligible. Patients were excluded for the following reasons: admission >48 hours after aneurysm rupture, pre-existing hypertension, or cardiac disease. Levels of BNP and cardiac troponin Ic were measured daily for 7 days. Echocardiography was performed by a blinded cardiologist on days 1, 2, and 7. Doppler signals from the mitral inflow, tissue Doppler, and the color M-mode-derived flow propagation velocity (FPV) were obtained to assess echo-estimated LVFP.

RESULTS

During a 3-year period, sixty-six consecutive patients with SAH were admitted. Thirty one patients were studied. The BNP level was >100 ng/L in 25 patients (80%) during the first 3 days, with a peak on day 2 (median, 126 ng/L) followed by a gradual decrease (median variation days 1 to 7, 70%). All patients had an ejection fraction >50%. Early transmitral velocity/tissue Doppler mitral annular early diastolic velocity was low: 5.4 (+/- 1.5) on day 1, 5.8 (+/- 1.2) on day 2, and 5.1 (+/- 0.9) on day 7. Early transmitral velocity/FPV was also low: 1.27 (+/- 0.4), 1.25 (+/- 0.3), and 1.1 (+/- 0.2) on days 1, 2, and 7, respectively. Cardiac troponin Ic levels ranged from 0 to 3.67 microg/L and were correlated with BNP (r = 0.63, P < 0.01).

CONCLUSIONS

BNP rises gradually over two days and return to normal within a week after SAH. Its release is associated with myocardial necrosis, but is unrelated to elevated LVFP assessed by echocardiography.

Work-in-progress toward incorporating patients' preferences in practice guidelines for imaging aneurysmal subarachnoid hemorrhage

RATIONALE AND OBJECTIVES

Patient-centered care has become a primary focus in clinical practice. In developing practice guidelines for clinical care, the patients' perspective is an important component.

MATERIALS AND METHODS

Patients' preferences are represented in a decision analytic model as quality-of-life weights for different health states associated with the aneurysmal subarachnoid hemorrhage population. The time-tradeoff method is used to obtain the individual patients' preferences, which are directly measured in quality-adjusted life years. An individualized care model is explained as a means of implementing a patient-centered approach into practice guidelines for clinical care. A method for calculating the expected value for societal benefit from improved decision making using an individualized care model is reviewed.

RESULTS

We discuss our work-in-progress towards incorporating patients' preferences in a decision analytic model for aneurysmal subarachnoid hemorrhage patients. The main methodologic concerns for using patients' preferences in cost-effectiveness analyses for developing practice guidelines are discussed.

CONCLUSION

Emphasis is placed on using patients' preferences and patient-centered outcome measures in cost-effectiveness analyses.

Nurses' prediction of volume status after aneurysmal subarachnoid haemorrhage: a prospective cohort study

Introduction

Patients who have suffered aneurysmal subarachnoid haemorrhage (SAH) often have derangements in blood volume, contributing to poor outcome. To guide fluid management, regular assessments of volume status must be conducted. We studied the ability of nursing staff to predict hypovolaemia or hypervolaemia, based on their interpretation of available haemodynamic data.

Methods

In a prospective cohort study, intensive care unit and medium care unit nurses, currently treating patients with recent SAH, were asked to predict present volume status. For their assessment they could use all available haemodynamic parameters (for example, heart rate, blood pressure, fluid balance). The nurses' assessments were compared with the actual circulating blood volume (CBV), as measured daily with pulse dye densitometry during the first 10 days after SAH. Normovolaemia was defined as a CBV of 60 to 80 ml/kg body weight; hypovolaemia as CBV under 60 ml/kg; severe hypovolaemia as CBV under 50 ml/kg and hypervolaemia as CBV above 80 ml/kg.

Results

A total of 350 combinations of volume predictions and CBV measurements were obtained in 43 patients. Prediction of hypovolaemia had a sensitivity of 0.10 (95% confidence interval [CI] = 0.06 to 0.16) and a positive predictive value of 0.37 (95% CI = 0.23 to 0.53) for actual hypovolaemia. The prediction of hypervolaemia had a sensitivity of 0.06 (95% CI = 0.01 to 0.16) and a positive predictive value of 0.06 (95% CI = 0.02 to 0.19) for actual hypervolaemia. Mean CBV was significantly lower in instances considered hypervolaemic than in instances considered normovolaemic.

Conclusions

Assessment of haemodynamic condition in patients with SAH by intensive care unit or medium care unit nurses does not adequately predict hypovolaemia or hypervolaemia, as measured using pulse dye densitometry. Fluid therapy after SAH may require guidance with more advanced techniques than interpretation of usual haemodynamic parameters.

The Utility and Benefits of External Lumbar CSF Drainage after Endovascular Coiling on Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

Cerebral vasospasm still remains a major cause of the morbidity and mortality, despite the developments in treatment of aneurysmal subarachnoid hemorrhage. The authors measured the utility and benefits of external lumbar cerebrospinal fluid (CSF) drainage to prevent the clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage in this randomized study.

METHODS

Between January 2004 and March 2006, 280 patients with aneurysmal subarachnoid hemorrhage were treated at our institution. Among them, 107 patients met our study criteria. The treatment group consisted of 47 patients who underwent lumbar CSF drainage during vasospasm risk period (about for 14 days after SAH), whereas the control group consisted of 60 patients who received the management according to conventional protocol without lumbar CSF drainage. We created our new modified Fisher grade on the basis of initial brain computed tomography (CT) scan at admission. The authors established five outcome criteria as follows : 1) clinical vasospasm; 2) GOS score at 1-month to 6-month follow-up; 3) shunt procedures for hydrocephalus; 4) the duration of stay in the ICU and total hospital stay; 5) mortality rate.

RESULTS

The incidence of clinical vasospasm in the lumbar drain group showed 23.4% compared with 63.3% of individuals in the control group. Moreover, the risk of death in the lumbar drain group showed 2.1% compared with 15% of individuals in the control group. Within individual modified Fisher grade, there were similar favorable results. Also, lumbar drain group had twice more patients than the control group in good GOS score of 5. However, there were no statistical significances in mean hospital stay and shunt procedures between the two groups. IVH was an important factor for delayed hydrocephalus regardless of lumbar drain.

CONCLUSION

Lumbar CSF drainage remains to play a prominent role to prevent clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage. Also, this technique shows favorable effects on numerous neurological outcomes and prognosis. The results of this study warrant clinical trials after endovascular treatment in patients with aneurysmal SAH.

Volume and electrolyte management

Osmolality is the primary determinant of water movement across the intact blood-brain barrier (BBB), and we can predict that reducing serum osmolality would increase cerebral oedema and intracranial pressure. Brain injury affects the integrity of the BBB to varying degrees. With a complete breakdown of the BBB, there will be no osmotic/oncotic gradient, and water accumulates (brain oedema) consequentially to the pathological process. In regions with very moderate BBB injury, the oncotic gradient may be effective. Finally, osmotherapy is effective in brain areas with normal BBB; hypertonic solutions (mannitol, hypertonic saline) dehydrate normal brain tissue, with a decrease in cerebral volume and intracranial pressure. In patients with brain pathology, volume depletion and/or hypotension greatly increase morbidity and mortality. In addition to management of intravascular volume, fluid therapy must often be modified for water and electrolyte (mainly sodium) disturbances. These are common in patients with neurological disease and need to be adequately treated.

Effects of hypervolemia and hypertension on regional cerebral blood flow, intracranial pressure, and brain tissue oxygenation after subarachnoid hemorrhage

OBJECTIVE

Hypertensive, hypervolemic, hemodilution therapy (triple-H therapy) is a generally accepted treatment for cerebral vasospasm after subarachnoid hemorrhage. However, the particular role of the three components of triple-H therapy remains controversial. The aim of the study was to investigate the influence of the three arms of triple-H therapy on regional cerebral blood flow and brain tissue oxygenation.

DESIGN

Animal research and clinical intervention study.

SETTING

Surgical intensive care unit of a university hospital.

SUBJECTS AND PATIENTS

Experiments were carried out in five healthy pigs, followed by a clinical investigation of ten patients with subarachnoid hemorrhage.

INTERVENTIONS

First, we investigated the effect of the three components of triple-H therapy under physiologic conditions in an experimental pig model. In the next step we applied the same study protocol to patients following aneurysmal subarachnoid hemorrhage. Mean arterial pressure, intracranial pressure, cerebral perfusion pressure, cardiac output, regional cerebral blood flow, and brain tissue oxygenation were continuously recorded. Intrathoracic blood volume and central venous pressure were measured intermittently. Vasopressors and/or colloids and crystalloids were administered to stepwise establish the three components of triple-H therapy.

MEASUREMENTS AND MAIN RESULTS

In the animals, neither induced hypertension nor hypervolemia had an effect on intracranial pressure, brain tissue oxygenation, or regional cerebral blood flow. In the patient population, induction of hypertension (mean arterial pressure 143 +/- 10 mm Hg) resulted in a significant (p < .05) increase of regional cerebral blood flow and brain tissue oxygenation at all observation time points. In contrast, hypervolemia/hemodilution (intrathoracic blood volume index 1123 +/- 152 mL/m) induced only a slight increase of regional cerebral blood flow while brain tissue oxygenation did not improve. Finally, triple-H therapy failed to improve regional cerebral blood flow more than hypertension alone and was characterized by the drawback that the hypervolemia/hemodilution component reversed the effect of induced hypertension on brain tissue oxygenation.

CONCLUSIONS

Vasopressor-induced elevation of mean arterial pressure caused a significant increase of regional cerebral blood flow and brain tissue oxygenation in all patients with subarachnoid hemorrhage. Volume expansion resulted in a slight effect on regional cerebral blood flow only but reversed the effect on brain tissue oxygenation. In view of the questionable benefit of hypervolemia on regional cerebral blood flow and the negative consequences on brain tissue oxygenation together with the increased risk of complications, hypervolemic therapy as a part of triple-H therapy should be applied with utmost caution.

Arginine vasopressin as a supplementary vasopressor in refractory hypertensive, hypervolemic, hemodilutional therapy in subarachnoid hemorrhage

INTRODUCTION

Hypertensive, hypervolemic, and hemodilutional (HHH) therapy for vasospasm in subarachnoid hemorrhage (SAH) refractory to phenylephrine requires high doses of catecholamines, leading to adverse adrenergic effects. Arginine vasopressin (AVP) has been shown to stabilize advanced shock states while facilitating reduction of catecholamine doses, but its use has never been reported in SAH. In this retrospective study, we investigated the hemodynamic effects and feasibility of supplementary AVP in refractory HHH therapy in SAH.

METHODS

Hemodynamic response (mean arterial pressure [MAP], heart rate, central venous pressure, cardiac index, systemic vascular resistance index, and end diastolic volume index) to a supplementary AVP infusion (0.01-0.04 IU/minute) was recorded within the first 24 hours in 22 patients. Secondary endpoints (serum sodium concentration, incidence of vasospasm, and intracranial pressure [ICP]) were compared to controls on HHH therapy with phenylephrine alone.

RESULTS

After initiation of AVP, MAP increased significantly compared to baseline. Phenylephrine doses decreased significantly, whereas other hemodynamic parameters remained stable. Serum sodium concentrations decreased similarly in both groups (-5 +/- 7 mmol/L versus -6 +/- 4 mmol/L; p = 0.25). No detrimental effects on vasospasm incidence or ICP and cerebral perfusion pressure were noted.

CONCLUSION

AVP may be considered as an alternative supplementary vasopressor in refractory HHH therapy with phenylephrine in SAH. Although we did not observe any deleterious effect of AVP on cerebral circulation, close observation for development of cerebral vasospasm should be undertaken, until it is clearly demonstrated that AVP has no adverse effects on regional cerebral blood flow and symptomatic cerebral vasospasm. Our limited data suggest that low-dose AVP does not cause brain edema, but further study is merited.

Subarachnoid hemorrhage in the subacute stage: elevated apparent diffusion coefficient in normal-appearing brain tissue after treatment

PURPOSE

To prospectively evaluate whether subarachnoid hemorrhage (SAH) is associated with a change in the apparent diffusion coefficient (ADC) in normal-appearing brain parenchyma.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained for all patient and volunteer studies. One hundred patients (48 men, 52 women; mean age, 52 years +/- 12 [standard deviation]) with aneurysmal SAH underwent conventional and diffusion-weighted magnetic resonance (MR) imaging at a mean of 9 days +/- 3 after SAH to evaluate possible lesions caused by SAH, treatment of SAH, and vasospasm. Aneurysms were treated surgically (n = 70) or endovascularly (n = 30) before MR imaging. Diffusion-weighted MR imaging was performed at 1-year follow-up in 30 patients (10 men, 20 women; mean age, 51 years +/- 11). Thirty healthy age-matched volunteers (11 men, 19 women; mean age, 54 years +/- 16) underwent MR imaging with an identical protocol. ADC values were measured bilaterally in the gray and white matter (parietal, frontal, temporal, occipital lobes; cerebellum; caudate nucleus; lentiform nucleus; thalamus; and pons) that appeared normal on T2-weighted and diffusion-weighted MR images. Linear mixed model was used for comparison of ADC values of supratentorial gray matter and white matter; general linear regression analysis was used for comparison of ADC values of cerebellum and pons.

RESULTS

In patients with SAH, the ADC values in normal-appearing white matter, with a single exception in the frontal lobe (P = .091), were significantly higher than they were in healthy volunteers (P </= .011). The differences disappeared by 1 year, except in parietal white matter (P = .045). The ADC values of cortical gray matter did not significantly differ between patients and volunteers (P >/= .121).

CONCLUSION

SAH and its treatment may cause global mild vasogenic edema in white matter and deep gray matter that is undetectable on T2-weighted and diffusion-weighted MR images but is detectable by measuring the ADC value in the subacute stage of SAH.

Racial differences in cerebral vasospasm: a systematic review of the literature

OBJECTIVE

Despite a significant body of clinical research and the widespread use of early intervention with aggressive postoperative management, cerebral vasospasm (CV) continues to contribute significantly to the morbidity and mortality of aneurysmal subarachnoid hemorrhage (aSAH). Many studies have evaluated predictive factors, although none to date has investigated a possible difference in the incidence of CV between Asian and white patients. We present a review of the modern aSAH literature to examine the incidence of CV in Japan and Europe, two highly researched populations.

METHODS

A literature search was performed using the Medline and PubMed databases. Studies conducted in Japan or Europe published between 1990 and 2004 that reported an incidence of CV after aSAH were subjected to a thorough review. Data from included studies were categorized by origin (Japan or Europe) and method of CV diagnosis (angiography, delayed ischemic neurological deficit, or new infarct attributable to CV), and then were combined. Recorded incidences then were compared using a chi test, and estimates of the relative risk of vasospasm were computed.

RESULTS

The initial literature search identified 102 studies, and 32 studies met all inclusion criteria. The incidence of vasospasm diagnosed by angiography, delayed ischemic neurological deficit, and computed tomography was significantly greater in Japanese studies (all P < 0.001). The relative risks for Japanese patients as compared with European patients were 2.04, 2.07, and 1.53 for angiographic CV, delayed ischemic neurological deficit, and new infarct, respectively.

CONCLUSION

Patients in Japanese studies were more likely to experience CV after aSAH across diagnostic methods. This may be a manifestation of genetic differences between Japanese and European populations. Clinicians should consider possible patient differences when interpreting CV research conducted in these populations.

Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage: An Overview of Pharmacologic Management

Cerebral vasospasm remains one of the leading causes of mortality in patients who experience a subarachnoid hemorrhage but survive the initial 24 hours. Vasospasm generally occurs 3-4 days after the initial subarachnoid hemorrhage and peaks at 5-7 days. The pathophysiology of vasospasm is poorly understood, which directly contributes to the inconsistency of management and creates a formidable challenge in clinical practice. Traditionally, hemodilution, hypervolemia, and induced hypertension (so-called triple H therapy); calcium channel blockers; and endovascular therapy have been used as either prophylactic therapy or treatment. However, management of vasospasm varies among physicians and institutions mainly because of a lack of large clinical trials and inconsistent results. Practice has been based primarily on case reports and the preference of each practitioner. Several experimental therapies have been explored; however, large, prospective, randomized controlled trials are needed to elucidate the role of these therapies.

Relative importance of hypertension compared with hypervolemia for increasing cerebral oxygenation in patients with cerebral vasospasm after subarachnoid hemorrhage

Object. Hypervolemia and hypertension therapy is routinely used for prophylaxis and treatment of symptomatic cerebral vasospasm at many institutions. Nevertheless, there is an ongoing debate about the preferred modality (hypervolemia, hypertension, or both), the degree of therapy (moderate or aggressive), and the risk or benefit of hypervolemia, moderate hypertension, and aggressive hypertension in patients following subarachnoid hemorrhage.

Methods. Monitoring data and patient charts for 45 patients were retrospectively searched to identify periods of hypervolemia, moderate hypertension, or aggressive hypertension. Measurements of central venous pressure, fluid input, urine output, arterial blood pressure, intracranial pressure, and oxygen partial pressure (PO2) in the brain tissue were extracted from periods ranging from 1 hour to 24 hours. For these periods, the change in brain tissue PO2 and the incidence of complications were analyzed.

During the 55 periods of moderate hypertension, an increase in brain tissue PO2 was found in 50 cases (90%), with complications occurring in three patients (8%). During the 25 periods of hypervolemia, an increase in brain oxygenation was found during three intervals (12%), with complications occurring in nine patients (53%). During the 10 periods of aggressive hypervolemic hypertension, an increase in brain oxygenation was found during six of the intervals (60%), with complications in five patients (50%).

Conclusions. When hypervolemia treatment is applied as in this study, it may be associated with increased risks. Note, however, that further studies are needed to determine the role of this therapeutic modality in the care of patients with cerebral vasospasm. In poor-grade patients, moderate hypertension (cerebral perfusion pressure 80–120 mm Hg) in a normovolemic, hemodiluted patient is an effective method of improving cerebral oxygenation and is associated with a lower complication rate compared with hypervolemia or aggressive hypertension therapy.

Cerebral vasospasm in subarachnoid hemorrhage

The treatment of vasospasm after subarachnoid hemorrhage remains a formidable challenge. The prompt recognition of this complication is essential to prevent ischemic damage. Initial orders should include adequate fluid and sodium supplementation to avoid volume depletion. Prophylactic hypervolemia is not effective in reducing the incidence of vasospasm and may be deleterious. Oral nimodipine (60 mg every 4 hours for 21 days) should be started on admission because it protects against delayed ischemic damage. Increasing blood flow velocities on serial transcranial Doppler studies are reliable indicators of early development of vasospasm. When symptomatic vasospasm occurs, hemodynamic augmentation therapy should be instituted. Crystalloids and colloids may be used to promote hypervolemia. Colloids may provide additional benefit by producing hemodilution. However, the rheological benefits of hemodilution may be offset by reduced oxygen carrying capacity when hematocrit drops below 28%. Hypertension may be induced by administering inotropic drugs and, in certain cases, cardiac output optimization using dobutamine also is necessary. When aggressive medical therapy fails to reverse ischemic deficits, prompt endovascular intervention is indicated. Focal vasospasm of larger vessels may be effectively treated with angioplasty and the benefits of this procedure are durable. Diffuse vasospasm involving smaller arterial branches may be treated with intra-arterial infusion of vasodilators, such as papaverine, verapamil, or nicardipine. Unfortunately, these dilatory effects tend to be short-lasting. In refractory cases, hypothermia may be considered, although value of this strategy remains largely unexplored.

Effect of human albumin administration on clinical outcome and hospital cost in patients with subarachnoid hemorrhage

OBJECT

Human albumin is used to induce hypervolemia (central venous pressure [CVP] > 8 mm Hg) after subarachnoid hemorrhage (SAH). Unfortunately, human albumin may increase the mortality rate in critically ill patients; because of this, its use became restricted in the authors' hospital in May 1999. The goal of this study was to determine the effect of human albumin on outcome and cost in patients with SAH before and after this restriction was put into place.

METHODS

All patients with aneurysmal SAH who were admitted to the authors' institution between May 1998 and May 2000 were studied. Basic demographic information, dosage of human albumin given, length of stay, and the incidence of in-hospital deaths and complications were collected. The authors obtained Glasgow Outcome Scale (GOS) scores at 3 months after SAH (good outcome, GOS > or = 4). Data were analyzed using t-test and chi-square analysis. Logistic regression was used to identify independent associations between use of human albumin and outcome. The authors studied 140 patients: 63 who were admitted between May 1998 and May 1999 (Group 1) and 77 treated between June 1999 and May 2000 (Group 2). Two subgroups of patients were further analyzed. Group 1 patients who received human albumin (albumin subgroup, 37 patients) and Group 2 patients who would have received albumin under the old protocol (that is, those who failed to achieve CVP > 8 mm Hg after normal saline administration; nonalbumin subgroup, 47 patients). Patients in the nonalbumin subgroup were more likely to be male (38% compared with 16%), to experience hypertension (55% compared with 30%), to suffer from hypomagnesemia (49% compared with 5.4%), and to have hydrocephalus (47% compared with 27%). There was a trend for these patients to have more vasospasm (28% compared with 19%, p = 0.2). Patients in the albumin subgroup were more likely to have a good outcome at 3 months.

CONCLUSIONS

Administration of human albumin after SAH may improve clinical outcome and reduce hospital cost.

Systematic review of the prevention of delayed ischemic neurological deficits with hypertension, hypervolemia, and hemodilution therapy following subarachnoid hemorrhage

OBJECT

There is uncertainty about the efficacy of hypertension, hypervolemia, and hemodilution (triple-H) therapy in reducing the occurrence of delayed ischemic neurological deficits (DINDs) and death after subarachnoid hemorrhage. The authors therefore conducted a systematic review to evaluate the efficacy of triple-H prevention in decreasing the rate of clinical vasospasm, DINDs, and death.

METHODS

The authors systematically reviewed studies identified based on a MEDLINE, EMBASE, and COCHRANE Register search of articles published between 1966 and 2001, and reference lists of identified articles. An independent assessment of each study's methodological quality, population, intervention, and outcomes (rates of symptomatic vasospasm, DINDs, and death) was performed. Summary relative risk estimates were calculated for the main outcomes using fixed- or random-effect models, as appropriate. Only four prospective, comparative studies with a total of 488 patients were identified. The median internal validity score was 0.5 (range 0-2); the median external validity score was 3 (range 2-6). Compared with no prevention, triple-H therapy was associated with a reduced risk of symptomatic vasospasm (relative risk [RR] 0.45, 95% confidence interval [CI] 0.32-0.65), but not DIND (RR 0.54, 95% CI 0.2-1.49). The risk of death was higher (RR 0.68, 95% CI 0.53-0.87). Sensitivity analyses including only randomized, controlled trials showed no evidence of statistically significant results for these major end points.

CONCLUSIONS

The paucity of information and important limitations in the design of the studies analyzed preclude evaluation of the efficacy of triple-H prevention and formulation of any recommendations regarding its use for the prevention of cerebral vasospasm.

Albumin use in neurosurgical critical care

STUDY OBJECTIVE

To examine the use of albumin in patients receiving neurosurgical intensive care.

DESIGN

Survey and chart review of albumin use in neurosurgical intensive care units.

SETTING

University of Kentucky Chandler Medical Center and American Brain Injury Consortium (ABIC).

SUBJECTS

Thirty-eight patients who underwent neurosurgery at the University of Kentucky Chandler Medical Center; members of the ABIC.

INTERVENTIONS

Chart review with attention to administration of albumin; mailed survey to 200 ABIC members.

MEASUREMENTS AND MAIN RESULTS

Patients admitted to the neurosurgical intensive care unit at the University of Kentucky Chandler Medical Center over a 6-month interval were evaluated. Albumin, either 5% or 25%, was prescribed for approximately 25% of patients. The indications for use were vasospasm and maintenance of cerebral perfusion pressure. The response rate for the ABIC survey was 39%. Respondents stated that normal saline and albumin were both primary fluid choices for the treatment of vasospasm. Twenty-two percent reported a reduction in albumin prescribing following a formal warning statement issued by the Food and Drug Administration regarding the use of albumin in critically ill patients.

CONCLUSIONS

Chart review revealed the primary indications for albumin in the neurosurgical intensive care unit, and our survey data demonstrated the lack of consensus among neurosurgeons regarding their fluid of choice for neurosurgery indications. Prospective, randomized investigations comparing colloids to crystalloids in patients receiving neurosurgical intensive care are required to help define the role of albumin in neurosurgery patients.

Ultra-early surgery for aneurysmal subarachnoid hemorrhage: outcomes for a consecutive series of 391 patients not selected by grade or age

OBJECT

This study was undertaken to determine the outcomes in an unselected group of patients treated with semiurgent surgical clipping of aneurysms following subarachnoid hemorrhage (SAH).

METHODS

A clinical management outcome audit was conducted to determine outcomes in a group of 391 consecutive patients who were treated with a consistent policy of ultra-early surgery (all patients treated within 24 hours after SAH and 85% of them within 12 hours). All neurological grades were included, with 45% of patients having poor grades (World Federation of Neurosurgical Societies [WFNS] Grades IV and V). Patients were not selected on the basis of age; their ages ranged between 15 and 93 years and 19% were older than 70 years. The series included aneurysms located in both anterior and posterior circulations. Eighty-eight percent of all patients underwent surgery and only 2.5% of the series were selectively withdrawn (by family request) from the prescribed surgical treatment. In patients with good grades (WFNS Grades I-III) the 3-month postoperative outcomes were independence (good outcome) in 84% of cases, dependence (poor outcome) in 8% of cases, and death in 9%. In patients with poor grades the outcomes were independence in 40% of cases, dependence in 15% of cases, and death in 45%. There was a 12% rate of rebleeding with all cases of rebleeding occurring within the first 12 hours after SAH; however, outcomes of independence were achieved in 46% of cases in which rebleeding occurred (43% mortality rate). Rebleeding was more common in patients with poor grades (20% experienced rebleeding, whereas only 5% of patients with good grades experienced rebleeding).

CONCLUSIONS

The major risk of rebleeding after SAH is present within the first 6 to 12 hours. This risk of ultra-early rebleeding is highest for patients with poor grades. Securing ruptured aneurysms by surgery or coil placement on an emergency basis for all patients with SAH has a strong rational argument.