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

Effectiveness of Cerebrospinal Fluid Lumbar Drainage Among Patients with Aneurysmal Subarachnoid Hemorrhage: An Updated Systematic Review and Meta-Analysis

INTRODUCTION

Cerebral vasospasm in patients after aneurysmal subarachnoid hemorrhage (aSAH) continues to be a major source of morbidity despite significant clinical and basic science research. The removal of blood and its degradation products from the subarachnoid space through prophylactic lumbar drainage (LD) is a favorable option. However, several studies have delivered conflicting conclusions on its efficacy after aSAH.

METHODS

Systematic searches of Medline, Embase, and Cochrane Central Register of Controlled Trials were performed. The primary outcome was a good functional outcome (modified Rankin scale score, 0-2). Secondary outcomes included symptomatic vasospasm, secondary cerebral infarction, and mortality.

RESULTS

A total of 14 studies reporting on 2473 patients with aSAH were included in the meta-analysis. Compared with the non-LD group, no significant differences were found in the rates of good functional outcomes in the LD group at discharge to 1 month (risk ratio [RR], 1.28; 95% confidence interval [CI], 0.64-2.58) or at 6 months (RR, 1.12; 95% CI, 0.97-1.41). These findings were consistent in the subgroup analyses of only randomized controlled trials or observational studies. LD was associated with lower rates of symptomatic vasospasm (RR, 0.61; 95% CI, 0.48-0.77), secondary cerebral infarction (RR, 0.59; 95% CI, 0.45-0.79), and mortality at discharge to 1 month (RR, 0.58; 95% CI, 0.41-0.82). The effect on mortality diminished at 6 months (RR, 0.70; 95% CI, 0.34-1.45). However, when analyzing only randomized controlled trials, the benefit of LD on lower rates of mortality continued even at 6 months (RR, 0.75; 95% CI, 0.58-0.99).

CONCLUSIONS

For aSAH patients, the use of LD is associated with benefits in the rates of vasospasm, secondary cerebral infarctions, and mortality, without an increased risk of adverse events.

Feasibility of Prompt Lumbar Drainage in Patients with Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Numerous studies have shown that continuous lumbar drainage (LD) reduces spontaneous subarachnoid hemorrhage (SAH)-related complications, decreasing the incidence of cerebral vasospasm, delayed cerebral ischemia , and hydrocephalus in patients treated with coiling or clipping, but performing LD before securing the aneurysm is still controversial. Our hospital has been implementing prompt LD for several years, and we present the results in this paper.

METHODS

Between January 2014 and December 2020, a total of 438 patients with SAH were included in this retrospective study. The indication for prompt LD was aneurysmal SAH of modified Fisher grade III or higher without dense intraventricular hemorrhage with obstructive hydrocephalus requiring extraventricular drainage or large intracranial hemorrhage requiring immediate decompression. Prompt LD was performed for 229 patients with SAH, and the control group included 209 patients. We compared in-hospital mortality and vasospasm or hydrocephalus occurrence and procedure-related complications between the two groups.

RESULTS

The in-hospital mortality rate was 7.4% for patients with prompt LD and 14.4% for patients without LD, and the difference was significant (P = 0.019). Vasospasm occurred in 10% of patients with prompt LD and 16.7% of controls (P = 0.039). Hydrocephalus requiring extraventricular drainage occurred in 10.9% of the LD group and 28.7% of the control group (P < 0.001). Rebleeding occurrence was 3.1% in the prompt LD group and 5.7% in the non-LD group (P = 0.168). Cerebrospinal fluid infection occurred in 0.4% of the prompt LD group and 1.4% of controls(P = 0.272).

CONCLUSIONS

Prompt LD is a feasible option for treating patients with selective aneurysmal SAH.

Continuous lumbar drainage after aneurysmal subarachnoid hemorrhage decreased malondialdehyde in cerebrospinal fluid and improved outcome

PURPOSE

The use of a continuous lumbar drain (LD) for the treatment of aneurysmal subarachnoid hemorrhage (aSAH), and malondialdehyde (MDA), a marker of oxidative stress, is correlated with clinical outcome. This study aimed to investigate the relationship between LD placement and MDA level after aSAH.

METHODS

Patients with modified Fisher's grade III and IV aSAH who underwent early aneurysm obliteration were enrolled. Cerebrospinal fluid (CSF) was obtained on day 7 after aSAH in non-LD group. In LD group, the LD was inserted on day 3 after aSAH for continuous CSF drainage. The levels of intrathecal hemoglobin, total bilirubin, ferritin, and MDA were measured.

RESULTS

There were 41 patients in non-LD group (age: 58.7 ± 13.7 years; female: 61.0%) and 48 patients in LD group (age: 58.3 ± 10.4 years; female: 79.2%). There were more favorable outcomes (Glasgow Outcome Scale ≥4) at 3 months after aSAH in LD group (p = 0.0042). The intrathecal hemoglobin, total bilirubin, ferritin, and MDA levels at day 7 after aSAH were all significantly lower in LD group. An older age (>60 years) (p = 0.0293), higher MDA level in the CSF (p = 0.0208), and delayed ischemic neurological deficit (p = 0.0451) were independent factors associated with unfavorable outcomes. LD placement was associated with a decreased intrathecal MDA level on day 7 after aSAH (p < 0.001).

CONCLUSION

The intrathecal MDA level at day 7 after aSAH can be an effective outcome indicator in modified Fisher's grade III/IV aSAH. Continuous CSF drainage via a LD can decrease the intrathecal MDA level and improve the functional outcome.

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.

Targeting Hemoglobin to Reduce Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

Delayed cerebral ischemia (DCI) continues to be a sequela of aneurysmal subarachnoid hemorrhage (aSAH) that carries significant morbidity and mortality. Aside from nimodipine, no therapeutic agents are available to reduce the incidence of DCI. Pathophysiologic mechanisms contributing to DCI are poorly understood, but accumulating evidence over the years implicates several factors. Those have included microvessel vasoconstriction, microthrombosis, oxidative tissue damage, and cortical spreading depolarization as well as large vessel vasospasm. Common to these processes is red blood cell leakage into the cerebrospinal fluids (CSF) and subsequent lysis which releases hemoglobin, a central instigator in these events. This has led to the hypothesis that early blood removal may improve clinical outcome and reduce DCI. This paper will provide a narrative review of the evidence of hemoglobin as an instigator of DCI. It will also elaborate on available human data that discuss blood clearance and CSF drainage as a treatment of DCI. Finally, we will address a recent novel device that is currently being tested, the Neurapheresis CSF Management System™. This is an automated dual-lumen lumbar drainage system that has an option to filter CSF and return it to the patient.

Lumbar Drainage After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

OBJECTIVE

This study reviews the use of lumbar drains (LDs) after aneurysmal subarachnoid hemorrhage (aSAH) and compares the outcomes to those associated with external ventricular drains (EVDs) and controls.

METHODS

A comprehensive search of the literature was performed. English language studies with a sample size of more than 10 patients were included. One-arm and 2-arm meta-analyses were designed to compare external drainage groups. Random-effects models, heterogeneity measures, and risk of bias were calculated.

RESULTS

Seventeen studies were included in the meta-analysis. The 2-arm meta-analysis comparing the LD to no drainage after aSAH found a significant improvement in the postoperative modified Rankin Scale (mRS) score (0-2) within 1 month of hospital discharge in the LD group (P = 0.003), a lower mortality rate (P = 0.03), fewer cases of clinical vasospasm (P = 0.007), and a lower incidence of ischemic stroke or delayed ischemic neurological deficits (P = 0.003). When the LD was compared to EVDs, a significant improvement in the postoperative mRS score (0-2) within 1 month of discharge was found in the LD group (P < 0.001). In the LD group, rebleeding occurred in 15 (3.4%) cases and meningitis occurred in 50 (4.7%) cases.

CONCLUSIONS

Compared with patients without cerebrospinal fluid drainage, patients with the LD after aSAH had lower mortality rates, lower risk of clinical vasospasm, and lower risk of ischemic stroke, and they were more likely to have an mRS score of 0-2 within 1 month of discharge. Compared with patients with EVDs, patients with the LD were more likely to have an mRS score of 0-2 within 1 month of discharge.

Criteria for Cerebrospinal Fluid Diversion in Retractorless Sphenoid Wing Meningioma Surgery: A Technical Report

Objective  Sphenoid wing meningiomas (SWMs) can present surgical challenges, in that they are often obscured by overlying brain, encase critical neurovascular structures, and obliterate cerebrospinal fluid (CSF) cisterns. While brain retraction can enable access, its use can have potentially deleterious effects. We report the benefits and outcomes of the criteria we have developed for use of cerebrospinal diversion to perform retractorless surgery for SWMs. Design  Technical report. Setting  Yale School of Medicine and Yale New Haven Hospital. Participants  Between May, 2019 and December, 2020, ten consecutive patients were included who met the presented criteria for SWM surgery with preoperative lumbar drain (LD) placement. Main Outcome Measures  Length of hospital stay, surgical complications, and extent of resection. Results  We have developed the following criteria for LD placement in patients with SWMs such that LDs are preoperatively placed in patients with tumors with one or more of the following criteria: (1) medial location along the sphenoid wing, (2) vascular encasement resulting in obliteration of the optic carotid cistern and/or proximal sylvian fissure, and/or (3) the presence of associated edema. CSF release, after craniotomy and sphenoid wing removal, allowed for optimization of exposure, leading to the maximal safe extent of tumor resection without brain retraction or any complications. Conclusions  Preoperative LD placement is effective in allowing for maximal extent of resection of SWMs and may be considered in cases where local CSF release is not possible. This technique is useful in those tumors located more medially, with encasement of the vasculature and/or associated with edema.

Update on intrathecal management of cerebral vasospasm: a systematic review and meta-analysis

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) accounts for a relatively small portion of strokes but has the potential to cause permanent neurological deficits. Vasospasm with delayed ischemic neurological deficit is thought to be responsible for much of the morbidity associated with aSAH. This has illuminated some treatment options that have the potential to target specific components of the vasospasm cascade. Intrathecal management via lumbar drain (LD) or external ventricular drain (EVD) offers unique advantages in this patient population. The aim of this review was to provide an update on intrathecal vasospasm treatments, emphasizing the need for larger-scale trials and updated protocols using data-driven evidence.

METHODS

A search of PubMed, Ovid MEDLINE, and Cochrane databases included the search terms (subarachnoid hemorrhage) AND (vasospasm OR delayed cerebral ischemia) AND (intrathecal OR intraventricular OR lumbar drain OR lumbar catheter) for 2010 to the present. Next, a meta-analysis was performed of select therapeutic regimens. The primary endpoints of analysis were vasospasm, delayed cerebral ischemia (DCI), cerebral infarction, and functional outcome.

RESULTS

Twenty-nine studies were included in the analysis. There were 10 studies in which CSF drainage was the primary experimental group. Calcium channel antagonists were the focus of 7 studies. Fibrinolytics and other vasodilators were each examined in 6 studies. The meta-analysis included studies examining CSF drainage via LD (n = 4), tissue plasminogen activator in addition to EVD (n = 3), intraventricular nimodipine (n = 2), and cisternal magnesium (n = 2). Results showed that intraventricular nimodipine decreased vasospasm (OR 0.59, 95% CI 0.37-0.94; p = 0.03). Therapies that significantly reduced DCI were CSF drainage via LD (OR 0.47, 95% CI 0.25-0.88; p = 0.02) and cisternal magnesium (OR 0.27, 95% CI 0.07-1.02; p = 0.05). CSF drainage via LD was also found to significantly reduce the incidence of cerebral infarction (OR 0.35, 95% 0.24-0.51; p < 0.001). Lastly, functional outcome was significantly better in patients who received CSF drainage via LD (OR 2.42, 95% CI 1.39-4.21; p = 0.002).

CONCLUSIONS

The authors' results showed that intrathecal therapy is a safe and feasible option following aSAH. It has been shown to attenuate cerebral vasospasm, reduce the incidence of DCI, and improve clinical outcome. The authors support the use of intrathecal management in the prevention and rescue management of cerebral vasospasm. More randomized controlled trials are warranted to determine the best combination of pharmaceutical agents and administration route in order to formulate a standardized treatment approach.

Trehalose decreases blood clotting in the cerebral space after experimental subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) frequently results in several serious complications, such as cerebral vasospasm. We previously reported the effect of trehalose on vasospasm, inflammatory responses, and lipid peroxidation induced by blood exposure. Herein, to further elucidate the mechanism of action of trehalose, we investigated whether or not post-administration of trehalose can directly influence blood clotting in the cistern. As a result of trehalose injection after the onset of experimental SAH, blood clotting around the basilar artery was clearly inhibited. We also found that trehalose positively impacted coagulation and fibrinolysis parameters in rat, rabbit and human plasma in vitro. These findings suggest that trehalose has suppressive effects on blood clotting in addition to vasospasm, inflammatory responses, and lipid peroxidation after SAH.

Impact of Neurapheresis System on Intrathecal Cerebrospinal Fluid Dynamics: A Computational Fluid Dynamics Study

It has been hypothesized that early and rapid filtration of blood from cerebrospinal fluid (CSF) in postsubarachnoid hemorrhage patients may reduce hospital stay and related adverse events. In this study, we formulated a subject-specific computational fluid dynamics (CFD) model to parametrically investigate the impact of a novel dual-lumen catheter-based CSF filtration system, the Neurapheresis™ system (Minnetronix Neuro, Inc., St. Paul, MN), on intrathecal CSF dynamics. The operating principle of this system is to remove CSF from one location along the spine (aspiration port), externally filter the CSF routing the retentate to a waste bag, and return permeate (uncontaminated CSF) to another location along the spine (return port). The CFD model allowed parametric simulation of how the Neurapheresis system impacts intrathecal CSF velocities and steady-steady streaming under various Neurapheresis flow settings ranging from 0.5 to 2.0 ml/min and with a constant retentate removal rate of 0.2 ml/min simulation of the Neurapheresis system were compared to a lumbar drain simulation with a typical CSF removal rate setting of 0.2 ml/min. Results showed that the Neurapheresis system at a maximum flow of 2.0 ml/min increased average steady streaming CSF velocity 2× in comparison to lumbar drain (0.190 ± 0.133 versus 0.093 ± 0.107 mm/s, respectively). This affect was localized to the region within the Neurapheresis flow loop. The mean velocities introduced by the flow loop were relatively small in comparison to normal cardiac-induced CSF velocities.

External Ventricular Drains After Subarachnoid Hemorrhage: Is Less More?

External ventricular drains (EVD) are essential in the early management of hydrocephalus and elevated intracranial pressure after subarachnoid hemorrhage (SAH). Once in place, management of the EVD is thought to influence long-term patient outcomes, rates of ventriculitis, incidence of delayed cerebral ischemia, need for a ventriculoperitoneal shunt, and intensive care unit (ICU) and hospital length of stay. The available evidence supports adopting early clamp trials and intermittent cerebrospinal fluid (CSF) drainage. However, a recent survey demonstrated that most neurological ICUs employ the opposite approach of continuously open EVDs and gradual weaning. In this article, we review the literature and arguments for and against the different EVD approaches. We conclude that an early clamp trial and intermittent CSF drainage can be safe and result in fewer EVD complications and shorter length of stay. Given the discrepancy between the available evidence and current practice, more studies on the optimal management of EVDs are warranted with the greatest need for multicenter prospective studies.

Effects of a new magnesium-rich artificial cerebrospinal fluid on contractile 5-hydroxytryptamine and endothelin receptors in rat cerebral arteries

Objectives Cerebral vasospasm after subarachnoid haemorrhage (SAH) is associated with cerebrovascular contractile receptor upregulation resulted from haemolysis in the subarachnoid space. This study developed a new magnesium-rich artificial cerebrospinal fluid (MACSF) formula and investigated its effects on receptor-mediated contraction in rat basilar arteries. Methods Clear and haemorrhagic cerebrospinal fluid (CSF) were collected from patients with hydrocephalus or SAH. MACSF was freshly prepared using clinical intravenous injections. Rat basilar arteries were segmented and incubated with clear CSF, haemorrhagic CSF or MACSF. The contractile responses were studied by myograph. The messenger ribonucleic acid (mRNA) and protein expression of 5-hydroxytryptamine 1B (5-HT_1B), endothelin subtype B (ET_B) and endothelin subtype A (ET_A) receptors were evaluated by real-time polymerase chain reaction (PCR) and Western blot analyses. Results Haemorrhagic CSF exposure shifted the contractile curves induced by 5-hydroxytryptamine (5-HT), sarafotoxins 6c (S6c) and endothelin-1 (ET-1) leftward with increased maximal contraction values. Furthermore, mRNA and protein expression were markedly elevated for 5-HT_1B, ET_B and ET_A receptors on arteries exposed to haemorrhagic CSF. However, the contractile responses to 5-HT, S6c or ET-1 and expression of 5-HT_1B, ET_B and ET_A receptors in rat cerebral arteries exposed to MACSF remained unaffected compared to those exposed to clear CSF. Besides, unlike normal saline which can inactive in-vitro vessels, MACSF can maintain their physiological activity. Conclusion Haemorrhagic CSF induces upregulation of 5-HT_1B, ET_B and ET_A receptors in rat cerebral arteries. However, MACSF can maintain in-vitro rat basilar arteries in good physiological activity and normal expression of contractile 5-HT and ET receptors.

Outcomes of microsurgical clipping vs coil embolization for ruptured aneurysmal subarachnoid hemorrhage: A multicenter real-world analysis of 583 patients in China

Aneurysmal subarachnoid hemorrhage (SAH) is a complex neurovascular syndrome with high disability and mortality. SAH patients may be managed with surgical clipping or coil embolization. In this study, we provided a real-world analysis of the outcome and prognostic factors of aneurysmal SAH in patients treated with coil embolization or microsurgical clipping.We retrospectively analyzed the medical records of aneurysmal SAH patients (n = 583) who underwent treatment at the First Hospital and the Second Hospital of Hebei Medical University, and Tangshan Worker's Hospital in China. All patients were evaluated by a combined neurosurgery and interventional neuroradiology team. Microsurgical aneurysmal clipping was performed using the skull base approach, while coil embolization was performed with bare platinum coils (with or without balloon assistance). The primary outcome was the Glasgow Outcome Scale (GOS) score at discharge.A total of 583 patients were included in this study, of which 397 (68.1%) of them underwent clipping and 186 (31.9%) received coil embolization. The patient cohort consisted of both poor grade and good grade aneurysmal SAH: 441 (75.6%) patients had good-grade (Hunt and Hess grade II or III) and 142 (24.4%) had poor grade (Hunt and Hess grade IV or V). Overall, 123 (21%) patients had unfavorable neurologic outcome (GOS score 1-3) and 460 (78.9%) patients had favorable neurologic outcome (GOS score 4 or 5). The mean GOS score at discharge was comparable for patients who underwent clipping and those received coil embolization (P > .05). Multivariate analysis showed that clipping only [OR (95%CI): 0.03 (0.01, 0.36); P = .000] and clipping with CSF drainage [OR (95%CI): 0.41 (0.18, 0.89); P = .001] were independent factors of a favorable outcome in patients with aneurysmal SAH. Coil embolization with hematoma removal [OR (95%CI): 0.03 (0.01, 0.36); P = .000] was also an independent determinant of a favorable outcome. High baseline Fisher grades were associated with significantly increased risk of an unfavorable outcome [OR (95%CI): 2.08 (1.30, 3.33); P = .002].Our findings suggested that both coil embolization and microsurgical clipping are viable treatment options for aneurysmal SAH patients. Procedures, such as CSF drainage and hematoma removal, performed in parallel with coil embolization and chipping should be considered when treating individual patients.

Predictive Value of Cerebral Autoregulation Impairment for Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage: A Meta-Analysis

OBJECTIVE

Delayed cerebral ischemia (DCI) happens in about 30% of patients with aneurysmal subarachnoid hemorrhage (SAH) and is related to higher mortality and disability. Some studies have shown cerebral autoregulation impairment can be a predictor of DCI in aneurysmal SAH. We conducted this meta-analysis to evaluate the predictive value of cerebral autoregulation impairment for DCI based on the current literature.

METHODS

A systematic literature search was performed in PubMed and Embase. According to inclusion and exclusion criteria, 2 authors screened the records and extracted data from the included studies. Pooled sensitivity, specificity, and their 95% confidence intervals (CIs) were obtained. To investigate the overall accuracy, a summary receiver operating characteristic (SROC) curve was built and the area under SROC curve was calculated. Deeks' linear regression was used to assess the publication bias. All statistical analyses were performed with Stata 14.0.

RESULTS

A total of 7 studies were finally included in this meta-analysis. The pooled sensitivity and specificity values of impaired cerebral autoregulation for DCI prediction were 0.79 (95% CI, 0.65-0.88) and 0.85 (95% CI, 0.615-0.96). Moreover, the area under the SROC curve of cerebral autoregulation impairment for DCI prediction was 0.87 (95% CI, 0.835-0.89). No obvious publication bias was found in Deeks' linear regression (P = 0.99).

CONCLUSIONS

Cerebral autoregulation impairment can be a helpful predictor of DCI in aneurysmal SAH. Its accuracy for DCI prediction should be verified by more studies in the future.

Does Neurosurgical Clipping or Endovascular Coiling Lead to More Cases of Delayed Hydrocephalus in Patients with Subarachnoid Hemorrhage?

Objective

We investigated whether clipping or endovascular treatment (EVT) can reduce the incidence of delayed hydrocephalus. We also investigated whether additional procedures, namely lumbar drainage and extra-ventricular drainage (EVD), decrease the incidence of delayed hydrocephalus in patients with subarachnoid hemorrhage (SAH).

Materials and Methods

One-hundred and fifty-two patients who had undergone an operation for SAH were enrolled in this study. Clinical data, radiological data, and procedural data were investigated. Procedural data included the operating technique (clipping vs. EVT) and the use of additional procedures (no procedure, lumbar drainage, or EVD). Delayed hydrocephalus was defined as a condition in which the Evan's index was 0.3 or higher, as assessed using brain computed tomography more than 2 weeks after surgery, requiring shunt placement due to neurological deterioration.

Results

Of the 152 patients, 45 (29.6%) underwent surgical clipping and 107 (70.4%) underwent EVT. Twenty-five (16.4%) patients developed delayed hydrocephalus. Age (p = 0.019), procedure duration (p = 0.004), and acute hydrocephalus (p = 0.030) were significantly correlated with the incidence of delayed hydrocephalus. However, the operation technique (p = 0.593) and use of an additional procedure (p = 0.378) were not significantly correlated with delayed hydrocephalus incidence.

Conclusion

No significant difference in the incidence of delayed hydrocephalus was associated with operation technique or use of an additional procedure in patients with SAH. However, delayed hydrocephalus was significantly correlated with old age, long procedural duration, and acute hydrocephalus. Therefore, we recommend that additional procedures should be discontinued as soon as possible.

Population Pharmacokinetics of Combined Intravenous and Local Intrathecal Administration of Meropenem in Aneurysm Patients with Suspected Intracranial Infections After Craniotomy

BACKGROUND AND OBJECTIVE

For patients with intracranial infection, local intrathecal administration of meropenem may be a useful method to obtain a sufficient drug concentration in the cerebral spinal fluid (CSF). However, a large inter-individual variability may pose treatment efficacy at risk. This study aimed to identify factors affecting drug concentration in the CSF using population pharmacokinetics method.

METHODS

After craniotomy, aneurysm patients with an indwelling lumbar cistern drainage tube who received a combined intravenous and intrathecal administration of meropenem for the treatment of suspected intracranial infection were enrolled. Venous blood and CSF specimens were collected for determining meropenem concentrations. Nonlinear mixed-effects modeling method was used to fit blood and CSF concentrations simultaneously and to develop the population pharmacokinetic model. The proposed model was applied to simulate dosage regimens.

RESULTS

A three-compartmental model was established to describe meropenem in vivo behavior. Lumbar CSF drainage resulted in a drug loss, and drug clearance in CSF (CL_CSF) was employed to describe this. The covariate analysis found that the drainage volume (mL/day) was strongly associated with CL_CSF, and the effect of creatinine clearance was significant on the clearance of meropenem in blood (CL). Visual predictive check suggested that the proposed pharmacokinetic model agreed well with the observations. Simulation showed that both intravenous and intrathecal doses should be increased with the increases of minimum inhibitory concentration and daily CSF drainage volume.

CONCLUSION

This model incorporates covariates of the creatinine clearance and the drainage volume, and a simple to use dosage regimen table was created to guide clinicians with meropenem dosing.

The effect of anesthetic agents on cerebral vasospasms after subarachnoid hemorrhage: A retrospective study

Cerebral vasospasm is the most important cause of morbidity after an aneurysm clipping in the early postoperative period. The aim of this retrospective study was to evaluate whether the incidence of vasospasms differs when using propofol or desflurane for an emergent aneurysm clipping.The data from 102 patients (50 in the propofol group, 52 in the desflurane group) were analyzed. The occurrence of vasospasm based on daily transcranial Doppler, angiography, and cerebral infarction during 14 days after surgery were compared by anesthetic agents. Postoperative data including Glasgow Coma Scale (GCS) score on day 14 after surgery, and the Glasgow Outcome Scale (GOS) score at 3 months were documented.Patients that intraoperatively received propofol for anesthesia maintenance, had higher incidence of transcranial Doppler (TCD)-evident vasospasm than those that received desflurane (54% vs 30.8%, P = .027). The occurrence of TCD-evident vasospasm was still higher (odds ratio: 2.84; 95% confidence interval: 1.12-7.20) in the propofol group than in the desflurane group after adjusting for confounding factors. However, the incidence of angiographic vasospasm, cerebral infarction, and interventions to treat cerebral vasospasms were similar between both groups. GCS score on day 14 after surgery and the GOS score at 3 months were similar between groups.No effect of anesthetic agents on angiographic vasospasm, cerebral infarction, or clinical outcome was observed, whereas desflurane anesthesia was associated with a lower incidence of TCD-evident vasospasms compared to propofol anesthesia. Our study provides a basis for further randomized controlled studies in a larger patient population to clarify the effects of anesthetic agents on the occurrence of cerebral vasospasms.

Novel Dual Lumen Catheter and Filtration Device for Removal of Subarachnoid hemorrhage: First Case Report

BACKGROUND AND IMPORTANCE

The amount of subarachnoid blood and the presence of toxic blood breakdown products in the cerebrospinal fluid (CSF) have long been associated with poor outcomes in aneurysmal subarachnoid hemorrhage. The Neurapheresis™ system (Minnetronix Inc, St. Paul, Minnesota) has been developed to filter CSF and remove blood products, and is being investigated for safety and feasibility in the ExtracorPoreal FILtration of subarachnoid hemorrhage via SpinaL CAtheteR (PILLAR) study. We report the first case using this novel device.

CLINICAL PRESENTATION

A 65-yr-old female presented with a ruptured left posterior communicating artery aneurysm. Following placement of a ventriculostomy and coil embolization of her aneurysm, the patient underwent placement of a lumbar dual lumen catheter for CSF filtration as part of the PILLAR study. In this case, a total of 9 h of filtration during 31 h of catheter indwelling resulted in 309.47 mL of processed CSF without complication. Computed tomography images demonstrated an interval reduction of subarachnoid hemorrhage immediately after filtration. The patient was discharged home on postbleed day 11 and at 30 d showed good recovery.

CONCLUSION

Safety of the Neurapheresis procedure was confirmed in this first case, and we will continue to evaluate safety of the Neurapheresis system through the PILLAR trial.

Volume of cerebrospinal fluid drainage as a predictor for pretreatment aneurysmal rebleeding

OBJECTIVE

Initiation of external CSF drainage has been associated with a significant increase in rebleeding probability after aneurysmal subarachnoid hemorrhage (aSAH). However, the implications for acute management are uncertain. The purpose of this study was to evaluate the role of the amount of drained CSF on aneurysmal rebleeding.

METHODS

Consecutive patients with aSAH were analyzed retrospectively. Radiologically confirmed cases of aneurysmal in-hospital rebleeding were identified and predictor variables for rebleeding were retrieved from hospital records. Clinical predictors were identified through multivariate analysis, and logistic regression analysis was performed to ascertain the cutoff value for the rebleeding probability.

RESULTS

The study included 194 patients. Eighteen cases (9.3%) of in-hospital rebleeding could be identified. Using multivariate analysis, in-hospital rebleeding was significantly associated with initiation of CSF drainage (p = 0.001) and CSF drainage volume (63 ml [interquartile range (IQR) 55–69 ml] vs 25 ml [IQR 10–35 ml], p < 0.001). Logistic regression showed that 58 ml of CSF drainage within 6 hours results in a 50% rebleeding probability. The relative risk (RR) for rebleeding after drainage of more than 60 ml in 6 hours was 5.4 times greater compared with patients with less CSF drainage (RR 5.403, 95% CI 2.481–11.767; p < 0.001, number needed to harm = 1.687).

CONCLUSIONS

Volume of CSF drainage was highly correlated with the probability of in-hospital aneurysmal rebleeding. These findings suggest that the rebleeding probability can be affected in acute management should the placement of an external ventricular catheter be necessary. This finding necessitates meticulous control of the amount of drained CSF and the development of a definitive treatment protocol for this group of patients.

Cerebral vasospasm: current understanding

PURPOSE OF REVIEW

With recent research trying to explore the pathophysiologic mechanisms behind vasospasm, newer pharmacological and nonpharmacological treatments are being targeted at various pathways involved. This review is aimed at understanding the mechanisms and current and future therapies available to treat vasospasm.

RECENT FINDINGS

Computed tomography perfusion is a useful alternative tool to digital subtraction angiography to diagnose vasospasm. Various biomarkers have been tried to predict the onset of vasospasm but none seems to be helpful. Transcranial Doppler still remains a useful tool at the bedside to screen and follow up patients with vasospasm. Hypertension rather than hypervolemia and hemodilution in 'Triple-H' therapy has been found to be helpful in reversing the vasospasm. Hyperdynamic therapy in addition to hypertension has shown promising effects. Endovascular approaches with balloon angioplasty and intra-arterial nimodipine, nicardipine, and milrinone have shown consistent benefits. Endothelin receptor antagonists though relieved vasospasm, did not show any benefit on functional outcome.

SUMMARY

Endovascular therapy has shown consistent benefit in relieving vasospasm. An aggressive combination therapy through various routes seems to be the most useful approach to reduce the complications of vasospasm.

Management of delayed cerebral ischemia after subarachnoid hemorrhage

For patients who survive the initial bleeding event of a ruptured brain aneurysm, delayed cerebral ischemia (DCI) is one of the most important causes of mortality and poor neurological outcome. New insights in the last decade have led to an important paradigm shift in the understanding of DCI pathogenesis. Large-vessel cerebral vasospasm has been challenged as the sole causal mechanism; new hypotheses now focus on the early brain injury, microcirculatory dysfunction, impaired autoregulation, and spreading depolarization. Prevention of DCI primarily relies on nimodipine administration and optimization of blood volume and cardiac performance. Neurological monitoring is essential for early DCI detection and intervention. Serial clinical examination combined with intermittent transcranial Doppler ultrasonography and CT angiography (with or without perfusion) is the most commonly used monitoring paradigm, and usually suffices in good grade patients. By contrast, poor grade patients (WFNS grades 4 and 5) require more advanced monitoring because stupor and coma reduce sensitivity to the effects of ischemia. Greater reliance on CT perfusion imaging, continuous electroencephalography, and invasive brain multimodality monitoring are potential strategies to improve situational awareness as it relates to detecting DCI. Pharmacologically-induced hypertension combined with volume is the established first-line therapy for DCI; a good clinical response with reversal of the presenting deficit occurs in 70 % of patients. Medically refractory DCI, defined as failure to respond adequately to these measures, should trigger step-wise escalation of rescue therapy. Level 1 rescue therapy consists of cardiac output optimization, hemoglobin optimization, and endovascular intervention, including angioplasty and intra-arterial vasodilator infusion. In highly refractory cases, level 2 rescue therapies are also considered, none of which have been validated. This review provides an overview of current state-of-the-art care for DCI management.

Effect of the drainage of cerebrospinal fluid in patients with aneurismal subarachnoid hemorrhage: A meta-analysis

BACKGROUND AND OBJECTIVES

Vasospasm-related injury such as delayed ischemic neurological defect (DIND) or cerebral infarction is an important prognostic factor for aneurismal subarachnoid hemorrhage (SAH). Whether cerebrospinal fluid (CSF) drainage can achieve a better outcome in aneurismal SAH patients after coiling or clipping remains the subject of debate. Here, we report a meta-analysis of the related available literature to assess the effect of continuous CSF drainage on clinical outcomes in patients with aneurismal SAH.

METHODS

Case-control studies regarding the association between aneurismal SAH and CSF drainage were systematically identified through online databases (PubMed, Web of Science, Elsevier Science Direct, and Springer Link). Inclusion and exclusion criteria were defined for the eligible studies. The fixed-effects model was performed when homogeneity was indicated. Alternatively, the random-effects model was utilized.

RESULTS

This meta-analysis included 11 studies. Continuous CSF drainage obviously improved patients' long-term outcome (odds ratio [OR] of 2.86, 95% confidence interval [CI], 1.37-5.98, P < 0.01). CSF drainage also reduced angiographic vasospasm (OR of 0.35, 95% CI, 0.23-0.51, P < 0.01), symptomatic vasospasm (OR of 0.32, 95% CI, 0.32-0.43, P < 0.01), and DIND (OR of 0.48, 95% CI, 0.25-0.91, P = 0.03), but there was no significant difference between the CSF drainage group and the no CSF drainage group on shunt-dependent hydrocephalus (SDHC) prevention (OR of 1.04, 95% CI, 0.52-2.07, P = 0.91). Further analysis on lumbar drainage (LD) and external ventricular drainage (EVD) indicated that LD had a better outcome (OR of 3.11, 95% CI, 1.18-8.23, P = 0.02), whereas no significant difference in vasospasm-related injury was detected between the groups (OR of 1.13, 95% CI, 0.54-2.37, P = 0.75).

CONCLUSION

Continuous CSF drainage is an effective treatment for aneurismal SAH patients; lumbar drainage showed lower complications, but more well-designed studies are required to verify and consolidate this conclusion.

Delayed cerebral ischaemia prevention and treatment after aneurysmal subarachnoid haemorrhage: a systematic review

: The leading cause of morbidity and mortality after surviving the rupture of an intracranial aneurysm is delayed cerebral ischaemia (DCI). We present an update of recent literature on the current status of prevention and treatment strategies for DCI after aneurysmal subarachnoid haemorrhage. A systematic literature search of three databases (PubMed, ISI Web of Science, and Embase) was performed. Human clinical trials assessing treatment strategies, published in the last 5 yr, were included based on full-text analysis. Study data were extracted using tables depicting study type, sample size, and outcome variables. We identified 49 studies meeting our inclusion criteria. Clazosentan, magnesium, and simvastatin have been tested in large high-quality trials but failed to show a beneficial effect. Cilostazol, eicosapentaenoic acid, erythropoietin, heparin, and methylprednisolone yield promising results in smaller, non-randomized or retrospective studies and warrant further investigation. Topical application of nicardipine via implants after clipping has been shown to reduce clinical and angiographic vasospasm. Methods to improve subarachnoid blood clearance have been established, but their effect on outcome remains unclear. Haemodynamic management of DCI is evolving towards euvolaemic hypertension. Endovascular rescue therapies, such as percutaneous transluminal balloon angioplasty and intra-arterial spasmolysis, are able to resolve angiographic vasospasm, but their effect on outcome needs to be proved. Many novel therapies for preventing and treating DCI after aneurysmal subarachnoid haemorrhage have been assessed, with variable results. Limitations of the study designs often preclude definite statements. Current evidence does not support prophylactic use of clazosentan, magnesium, or simvastatin. Many strategies remain to be tested in larger randomized controlled trials.

CLINICAL TRIAL REGISTRATION

This systematic review was registered in the international prospective register of systematic reviews.

PROSPERO

CRD42015019817.