Safety of dual antiplatelet therapy in the acute phase of aneurysmal subarachnoid hemorrhage: a propensity score-matched study

OBJECTIVE

With the evolution of neuroendovascular treatments, there is a great trend to treat acutely ruptured wide-necked aneurysms with stent-assisted coiling (SAC) and flow diverters (FDs), which inevitably requires dual antiplatelet therapy (DAPT). This therapy can increase the rate of hemorrhagic complications following other neurosurgical maneuvers, such as external ventricular drain (EVD) placement or removal. In this study, the authors aimed to evaluate the safety of DAPT in patients with aneurysmal subarachnoid hemorrhage (SAH) treated with SAC or FDs and the therapy's potential benefit in reducing cerebral ischemia and cerebral vasospasm.

METHODS

In this retrospective study, the authors reviewed the records of patients who had been admitted to their hospital with acute aneurysmal SAH and treated with SAC, FDs, and/or coiling between 2012 and 2022. Patients were classified into two groups: a DAPT group, including patients who had received DAPT for SAC or FDs, and a non-DAPT group, including patients who had not received any antiplatelet regimen and had been treated with coiling. Perioperative hemorrhagic and ischemic complications and clinical outcomes were compared between the two groups.

RESULTS

From among 938 cases of acute ruptured aneurysms treated during 10 years of study, 192 patients were included in this analysis, with 96 patients in each treatment group, after propensity score matching. All basic clinical and imaging characteristics were equivalent between the two groups except for the neck size of aneurysms (p < 0.001). EVD-related hemorrhage was significantly higher in the DAPT group than in the non-DAPT group (p = 0.035). In most patients, however, the EVD-related hemorrhage was insignificant. Parent artery or stent-induced thrombosis was higher in the DAPT group than in the non-DAPT group (p = 0.003). The rate of cerebral ischemia was slightly lower in the DAPT group than in the non-DAPT group (11.5% vs 15.6%, p = 0.399). In the multivariate analysis, cerebral ischemia, rebleeding before securing the aneurysm, extracranial hemorrhage, and cerebral vasospasm were the predictive factors of a poor clinical outcome (p < 0.001, p < 0.001, p = 0.038, and p = 0.038, respectively).

CONCLUSIONS

The DAPT regimen may be safe in the setting of acute aneurysmal SAH. Although EVD-related hemorrhage is more common in the DAPT group than the non-DAPT group, it is usually insignificant without any neurological deficit.

Transradial access for neurointerventional procedures: A practical approach

INTRODUCTION

Transradial approach (TRA) is a new technique proposed for performing cerebral angiography and neuro-interventional procedures. In this article, we sought to provide a step-by-step guide for carrying out a diagnostic cerebral angiography using this approach and summarize our center's experience.

MATERIAL AND METHODS

Records of patients since January 2020 were investigated, and data on demographic indices, reports of the procedures, outcomes, and complications were extracted. Then, these data were used to develop a step-by-step instruction for TRA cerebral angiography.

RESULTS

Two hundred eighty-nine patients matched our eligibility criteria with a mean age of 50 years and a female-to-male ratio of 1.18. Overall, TRA was carried out successfully for 97.2% (281 patients). In case TRA failed, transfemoral approach was considered for the procedure. Three minor complications (two vasospasm and one small hematoma) and two major complications (one pseudoaneurysm of the radial artery and one radial artery avulsion) were observed.

CONCLUSION

This article covers challenges a neurointerventionalist may face during a diagnostic cerebral angiography using TRA. Furthermore, our findings indicated that cerebral angiography with TRA might be performed safely and with a great success rate.

Endovascular treatment as the first-line approach for cure of low-grade brain arteriovenous malformation

OBJECTIVE

While microsurgery has been proposed as the first-line treatment for patients with low-grade (Spetzler-Martin grade I or II) brain arteriovenous malformations (bAVMs), recent studies have shown promising results for endovascular treatment (EVT) as a single proper choice for the management of this group of bAVMs. In this study, the authors evaluated the safety and efficacy of EVT as a first-line strategy for curing low-grade bAVMs at their center.

METHODS

All patients with low-grade bAVMs managed primarily by EVT between 2015 and 2021 were enrolled in this study. Patients were evaluated and treated by the same team and followed with the same protocol. The primary endpoint was the efficacy of EVT on the cure of low-grade bAVMs. The second endpoint was the safety of EVT for the treatment of low-grade bAVMs, including procedural complications and long-term clinical outcomes.

RESULTS

A total of 109 patients were enrolled and represented in the study population. The mean patient age was 31.6 ± 14.8 years. Forty-eight AVMs (44%) were Spetzler-Martin grade I and 61 (56%) were grade II. Of 99 patients who completed their EVT sessions, complete exclusion was achieved in 89 patients (89.9%). Overall, complete exclusion was achieved in 59.6% of patients after a single EVT session. At the 6-month follow-up, 106 patients (97.2%) had a favorable outcome. Four patients (4.6%) experienced transient neurological deficits, and 1 patient (0.9%) had a permanent neurological deficit.

CONCLUSIONS

EVT can be offered as the first choice of treatment for select patients with low-grade bAVMs, with a high cure rate and low morbidity.

Relationship between phosphatase and tensin homolog (PTEN) expression in high grade glioma and histopathologic findings

Introduction. Malignant glioma is resistant brain tumor to treatment and considered by aggressiveness that fails successful resection. Molecular pathways including PTEN related with tumor behavior. Materials and methods. We studied the immunohistochemical expression of PTEN in 32 brain surgical resection specimens with different histologic grades. All samples were from pathology department of Sina hospital in Tehran-Iran from 2020-2021. Results. From 32 patients, 21 (65.6%) had no PTEN staining. There was significant relationship between high age and no PTEN expression and average age with no PTEN staining was 54.05±14.01 years (P value: 0.044). There was significant relationship between necrosis in histopathologic evaluation with no PTEN staining (P value: 0.016). Also, there was no significant relationship between sex, tumor’s size, Tumor’s site, tumor’s grade, and primary or secondary type of tumor with PTEN staining (P value > 0.05). Conclusion. PTEN expression related to histopathologic features such as necrosis and age. PTEN can be introduced as an important prognostic indicator in high grade.

Roadmap for Conducting Neuroscience Research in the COVID-19 Era and Beyond: Recommendations From the SNACC Research Committee

The coronavirus disease 2019 (COVID-19) pandemic has impacted many aspects of neuroscience research. At the 2020 Society of Neuroscience in Anesthesiology and Critical Care (SNACC) Annual Meeting, the SNACC Research Committee met virtually to discuss research challenges encountered during the COVID-19 pandemic along with possible strategies for facilitating research activities. These challenges and recommendations are included in this Consensus Statement. The objectives are to: (1) provide an overview of the disruptions and challenges to neuroscience research caused by the COVID-19 pandemic, and; (2) put forth a set of consensus recommendations for strengthening research sustainability during and beyond the current pandemic. Specific recommendations are highlighted for adapting laboratory and human subject study activities to optimize safety. Complementary research activities are also outlined for both laboratory and clinical researchers if specific investigations are impossible because of regulatory or societal changes. The role of virtual platforms is discussed with respect to fostering new collaborations, scheduling research meetings, and holding conferences such that scientific collaboration and exchange of ideas can continue. Our hope is for these recommendations to serve as a valuable resource for investigators in the neurosciences and other research disciplines for current and future research disruptions.

Guillain–Barré Syndrome as a Neurological Complication of COVID-19 Infection: A Case Series and Review of the Literature

The novel coronavirus disease 2019 (COVID-19) is a global pandemic. Although the main clinical manifestations of the COVID-19 infection have confined to the respiratory system, there is some evidence suggesting the neuro-invasive potential of the COVID-19. There are limited reports of Guillain–Barré syndrome (GBS) as a peripheral nervous system complication of COVID-19 infection. We described four patients with COVID-19 infection who developed acute polyneuropathy with a final diagnosis of Guillain–Barré syndrome. COVID-19 may have the potential to invade the peripheral nervous system. GBS, as one of the critical neurological complications of COVID-19, could be considered as a post-infectious event.

Postoperative conversion disorder

Conversion disorder is a psychiatric disorder in which psychological stress causes neurologic deficits. A 28-year-old female surgical patient had uneventful general anesthesia and emergence but developed conversion disorder 1 hour postoperatively. She reported difficulty speaking, right-hand numbness and weakness, and right-leg paralysis. Neurologic examination and imaging revealed no neuronal damage, herniation, hemorrhage, or stroke. The patient mentioned failing examinations the day before surgery and discontinuing her prescribed antidepressant medication, leading us to diagnose conversion disorder, with eventual confirmation by neuroimaging and follow-up examinations.

Multimodality intraoperative neurophysiological monitoring during Onyx embolization of cerebrovascular malformations

General anesthesia prohibits neurological examination during embolization of cerebrovascular malformations when provocative testing prior to pedicle occlusion is needed. Intraoperative neurophysiological monitoring (IONM) has the potential to fill this gap but remains relatively unexplored. We conduct a retrospective review of consecutive patients with cerebrovascular malformations treated with Onyx (ethylene vinyl alcohol copolymer, dissolved in dimethyl sulfoxide) embolization under general anesthesia with IONM from 2009 to 2012. Somatosensory evoked potentials (SSEPs), transcranial motor evoked potentials (TcMEPs), visual evoked potential (VEPs), auditory brainstem response (ABR), and electroencephalography (EEG) were used selectively in all patients depending on the location of the malformation. Provocative testing combined with IONM was performed in 28 patients over 75 sessions. Three patients demonstrated changes in TcMEPs or ABR during provocative testing, which halted the planned embolization. Two patients demonstrated changes in baseline SSEPs after embolization, despite normal IONM during provocative testing, correlating with postprocedural contralateral weakness. Six patients developed visual deficits after arterial occlusion despite unchanged VEPs and occipital EEG during provocative testing and embolization. We therefore conclude that the sensitivity of TcMEPs and SSEPs is preferable to EEG, and we strongly caution against relying on occipital recorded VEPs to predict visual deficits.

Web-based educational activities developed by the Society for Neuroscience in Anesthesiology and Critical Care (SNACC): the experience of process, utilization, and expert evaluation

BACKGROUND

Web-based delivery of educational material by scientific societies appears to have increased recently. However, the utilization of such efforts by the members of professional societies is unknown. We report the experience with delivery of educational resources on the Web site of the Society for Neuroscience in Anesthesiology and Critical Care (SNACC), and utilization of those resources by members.

METHODS

Three web-based educational initiatives were developed over 1 year to be disseminated through the SNACC Web site (http://www.snacc.org) for society members: (1) The SNACC Bibliography; (2) "Chat with the Author"; and (3) Clinical Case Discussions. Content experts and authors of important new research publications were invited to contribute. Member utilization data were abstracted with the help of the webmaster.

RESULTS

For the bibliography, there were 1175 page requests during the 6-month period after its launch by 122/664 (19%) distinct SNACC members. The bibliography was utilized by 107/553 (19%) of the active members and 15/91 (16.5%) of the trainee members. The "Chats with the Authors" were viewed by 56 (9%) members and the Clinical Case Discussions by 51 (8%) members.

CONCLUSIONS

Educational resources can be developed in a timely manner utilizing member contributions without additional financial implications. However, the member utilization of these resources was lower than expected. These are first estimates of utilization of web-based educational resources by members of a scientific society. Further evaluation of such utilization by members of other societies as well as measures of the effectiveness and impact of such activities is needed.

Risk factors for delayed extubation in thoracic and lumbar spine surgery: a retrospective analysis of 135 patients

PURPOSE

Extubation may be delayed after spine surgery mainly for the concerns of airway safety. Risk factors for delayed extubation in cervical spine surgery have been described to include prolonged surgery time and amount of crystalloids or blood transfused. To date, risk factors for delayed extubation in thoracic or lumbar spine surgery have not been investigated. We retrospectively reviewed 135 consecutive patients from 2006 to 2009 who underwent thoracic or lumbar spine surgery by one particular surgeon to identify risk factors for delayed extubation.

METHODS

Data including patient factors, surgical time, anesthetic technique, blood loss, crystalloid and colloid administration, transfusion requirements, time to transfusion, and time to extubation were collected and analyzed. Delayed extubation was defined as the patient was not extubated in the operating room at completion of the surgery.

RESULTS

One hundred and eight patients were extubated in the OR. Delayed extubation occurred in 27 patients. Delayed extubation was significantly related to total operative time (6.6 ± 0.4 vs. 5.2 ± 0.1 h), volume of crystalloid replacement (6,018 ± 408 vs. 4,186 ± 130 cm3), volume of total colloids infused (787 ± 93 vs. 442 ± 36 cm3), intraoperative blood transfused (3.7 ± 0.5 vs. 0.7 ± 0.1 units); blood loss (2,137 ± 286 vs. 832 ± 50 cm3), and time to starting blood transfusion (106 ± 12 vs. 199 ± 9 min).

CONCLUSIONS

Our study suggests that intraoperative factors including prolonged surgical time, significant blood loss, larger volume of crystalloid and colloid infusion, and blood transfusion may be risk factors for delayed extubation following thoracic or lumbar spine surgery. Early blood transfusion may also increase the risk of delayed extubation. Patient factors did not affect extubation time.

Brain tissue oxygen monitoring to assess reperfusion after intra-arterial treatment of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm: a retrospective study

BACKGROUND AND PURPOSE

Cerebral vasospasm resistant to medical management frequently requires intra-arterial spasmolysis. Angiographic resolution of vasospasm does not provide physiologic data on the adequacy of reperfusion. We recorded pre- and postspasmolysis PbO(2) data in the endovascular suite to determine whether this physiologic parameter could be used to determine when successful reperfusion was established.

MATERIALS AND METHODS

Eight patients with 10 Licox monitors and cerebral vasospasm underwent intra-arterial spasmolysis. Pre- and postspasmolytic PbO(2) was recorded for comparison. Other physiologic parameters, such as CPP, ICP, SaO(2), and Fio(2), were also recorded.

RESULTS

Mean prespasmolysis PbO(2) recordings were 35.2 and 27.3 for the mild-to-moderate and moderate-to-severe vasospasm group, respectively. Mean postspasmolysis PbO(2) increased to 40.3 and 38.4, respectively, which was statistically significant (P < .05) for both groups. In 100% of instances in the moderate-to-severe group and 83% of instances in mild-to-moderate group, the mean PbO(2) increased after spasmolysis and correlated with improvement in angiographic vasospasm. Other physiologic parameters, such as CPP, ICP, SaO(2), and Fio(2), did not show any statistically significant difference before and after spasmolysis.

CONCLUSIONS

PbO(2) monitoring provides the interventionalist with an objective physiologic parameter to determine adequate spasmolysis. Further investigation is needed to establish target PbO(2) rates indicative of adequate reperfusion, which can be used in the endovascular suite.

Transcranial motor evoked potential changes induced by provocative testing during embolization of cerebral arteriovenous malformations in patients under total intravenous anesthesia

Cerebral motor evoked potential (MEP) monitoring during arteriovenous malformation (AVM) embolization is not well studied (Söderman et al. 2003). Alterations of cerebral blood flow (CBF) during cerebral embolization could cause ischemia/infarction to the cerebral cortex. Permanent loss of MEPs is correlated with a permanent motor deficit. We report a case of a patient undergoing AVM embolization during which transcranial electrical motor evoked potentials (TCeMEP) reliably predicted changes to CBF induced by selective methohexital testing. Our finding demonstrated that MEPs are a useful means of intraoperative monitoring of motor pathway integrity and predicting changes. The loss of MEP predicted and prevented severe postoperative motor deficits. Intraoperative neuromonitoring with SSEP, TCeMEP and continuous EEG revealed no changes until the posterior cerebral artery (PCA), but not the anterior cerebral artery (ACA), was injected. TCeMEP may be superior to somatosensory evoked potential (SSEP) and EEG monitoring in predicting motor impairment during AVM surgery.

Direct cortical stimulation but not transcranial electrical stimulation motor evoked potentials detect brain ischemia during brain tumor resection

Motor evoked potentials (MEPs) elicited by both direct cortical stimulation (DCS) and transcranial electrical stimulation are used during brain tumor resection. Parallel use of direct cortical stimulation motor evoked potentials (DCS-MEPs) and transcranial electrical stimulation motor evoked potentials (TCeMEPs) has been practiced during brain tumor resection. We report that DCS-MEPs elicited by direct subdural grid stimulation, but not TCeMEPs, detected brain ischemia during brain tumor resection. Following resection of a brainstem high-grade glioma in a 21-year-old, the threshold of cortical motor-evoked-potentials (cMEPs) increased from 13 mA to 20 mA while amplitudes decreased. No changes were noted in transcranial motor evoked potentials (TCMEPs), somatosensory evoked potentials (SSEPs), auditory evoked potentials (AEPs), anesthetics, or hemodynamic parameters. Our case showed the loss of cMEPs and SSEPs, but not TCeMEPs. Permanent loss of DCS-MEPs and SSEPs was correlated with permanent left hemiplegia in our patient even when appropriate action was taken. Parallel use of DCS- and TCeMEPs with SSEPs improves sensitivity of intraoperative detection of motor impairment. DCS may be superior to TCeMEPs during brain tumor resection.

Deep hypothermic circulatory arrest for treatment of renal carcinoma

The case of a 67-year-old woman with multiple medical problems who presented for resection of a metastatic renal cell carcinoma involving the posterior fossa, is presented. Anesthetic management of the patient, who suffered metastasis to the brain, and who required deep hypothermic circulatory arrest, is discussed.

Hyperbaric oxygenation mitigates focal cerebral injury and reduces striatal dopamine release in a rat model of transient middle cerebral artery occlusion

The usefulness of the administration of hyperbaric oxygen (HBO) in the treatment of acute focal cerebral ischemia remains debatable. A significant association exists between focal cerebral injury and an excessive release of extracellular dopamine (DA). In vivo microdialysis was used in the present study to examine the effect of HBO on DA release in the striatum during ischemia and reperfusion in rats. The histological changes occurring were also evaluated. Focal cerebral ischemia was induced by occlusion of the middle cerebral artery (MCA) using a surgically placed intraluminal filament. Control rats (n=8) were subjected to 1 h of ischemia, whilst the study rats (n=8) were in addition treated with HBO (2.8 atmospheres of absolute pressure 100% O(2)) during ischemia. Both groups were returned to breathing room air at normal pressure during reperfusion. Microdialysis samples were continuously collected at 15 min intervals at 2 microl.min(-1). The [mean (SE)] increase in release of striatal DA attained significance after 30 min of occlusion of MCA [170 (24)%], and continued to increase [268 (26)% at 45 min] reaching a peak level at 60 min [672 (59)%] before returning to the baseline level during the late reperfusion phase. There was no significant change in the level of DA in HBO treated rats during the period of ischemia. A significant reduction in edema and neuronal shrinkage were observed by histological examination in HBO treated rats when compared to the control rats. The results showed that HBO, when administered during ischemia, offered significant neuroprotection in our experimental model of transient focal cerebral ischemia in the rat. The mechanism seems to imply, at least in part, a reduced level of DA.

Guglielmi detachable coil: report of intraoperative complications

The newest therapy for cerebral aneurysm is the Guglielmi detachable coil (GDC). The authors describe the anesthetic management of two patients with intraoperative subarachnoid hemorrhage during Guglielmi coil placement. Various treatments for intraoperative hemorrhage are discussed, as are other common complications that can occur during placement of intravascular, intracranial coils. The placement of a ventriculostomy was a major contributing factor in the good outcome of both patients. Consideration should be given to placement of a ventriculostomy before the GDC procedure. Although the GDC procedure offers much promise, it is not a benign procedure and has its own set of complications that will no doubt challenge the neuroanesthesiologist.

Severe lumbar back pain following epidural injection of local anesthetic for epidural anesthesia. Case report and literature review

BACKGROUND AND OBJECTIVES

An epidural anesthetic was planned for a 75-year-old man scheduled for elective femoral-popliteal bypass grafting.

METHODS

Severe and persistent back pain and posterior thigh muscle spasm abruptly began 10 minutes after epidural injection of mepivacaine.

RESULTS

Signs of impending or evolving neurologic injury completely resolved shortly thereafter.

CONCLUSIONS

The worst case scenarios, epidural hematoma and unintentional epidural injection of an irritant, are discussed along with other differential diagnoses. The literature is reviewed to gain insight into this unusual clinical presentation.