Society for Neuroscience in Anesthesiology and Critical Care Expert Consensus Statement: Anesthetic Management of Endovascular Treatment for Acute Ischemic Stroke* Endorsed by the Society of NeuroInterventional Surgery and the Neurocritical Care Society

Association of local anesthesia versus conscious sedation with functional outcome of acute ischemic stroke patients undergoing embolectomy

PURPOSE

Compare functional outcomes of acute ischemic stroke patients undergoing embolectomy with either local anesthesia or conscious sedation. Secondarily, identify differences in hemodynamic parameters and complication rates between groups.

MATERIALS AND METHODS

Single institution, retrospective review of all acute ischemic stroke patients undergoing embolectomy between January 2014 and July 2018 (n = 185). Patients receiving general anesthesia (n = 27) were excluded. One-hundred and eleven of 158 (70.3%) composed the local anesthesia group, and 47 (29.7%) composed the conscious sedation group. Median age was 71 years (interquartile range 59-79). Seventy-eight (49.4%) were male. The median National Institute of Health stroke scale score was 17.5 (interquartile range 11-21). Hemodynamic, medication, complication, and functional outcome data were collected from the anesthesia protocol and medical records. Good functional outcome was defined as a three-month modified Rankin Scale < 2. A multivariate analysis was performed to estimate the association of anesthesia type on three-month modified Rankin Scale score.

RESULTS

Three-month modified Rankin Scale score <2 was similar between groups (p = 0.5). Patients receiving conscious sedation were on average younger than patients receiving local anesthesia (p = 0.01). Conscious sedation patients were more likely to receive intravenous thrombolytic prior to embolectomy (p = 0.025). The complication rate and hemodynamic parameters were similar between groups.

CONCLUSION

Functional outcome of acute ischemic stroke patients undergoing embolectomy appears to be similar for patients receiving local anesthesia and conscious sedation. This similarity may be beneficial to a future study comparing general anesthesia to local anesthesia and conscious sedation. The use of local anesthesia or conscious sedation does not significantly impact hemodynamic status.

Effect of Conscious Sedation vs. General Anesthesia on Outcomes in Patients Undergoing Mechanical Thrombectomy for Acute Ischemic Stroke: A Prospective Randomized Clinical Trial

Background: Although several studies have compared conscious sedation (CS) with general anesthesia (GA) in patients undergoing mechanical thrombectomy (MT), there has been no affirmative conclusion. We conducted this trial to assess whether CS is superior to GA for patients undergoing MT for acute ischemic stroke (AIS).

Methods: Acute ischemic stroke patients with anterior circulation large vascular occlusion were randomized into two groups. The primary outcome was modified Rankin scale score (0–2) at 90 days after stroke. Secondary outcomes included intraprocedural hemodynamics, time metrics, successful recanalization, neurointerventionalist satisfaction score, National Institutes of Health Stroke Scale (NIHSS) score, and Alberta Stroke Program Early CT Score (ASPECTS) at 48 h post-intervention, mortality at discharge and 3 months after stroke, and complications.

Results: Compared with the CS group, heart rate was significantly lower at T1–T8 in the GA group except at T4 (P < 0.05). Mean arterial pressure (MAP) and systolic blood pressure were significantly lower in the GA group at T4–T6 and T9 (P < 0.05). Pulse oxygen saturation was significantly higher at T2–T9 in the GA group (P < 0.05). There were no significant differences in time metrics, vasoactive drug use, occurrence of >20% fall in MAP, pre-recanalization time spent with >20% fall in MAP, neurointerventionalist satisfaction, successful recanalization rate, NIHSS, and ASPECTS scores at 48 h post-intervention, and mortality rate at discharge and 3 months after stroke (P > 0.05). The cerebral infarction rate at 30 days was greater in the CS group, but not significantly (P > 0.05). There were no differences in complication rates except for pneumonia (P > 0.05). Conversion rate from CS to GA was 9.52%.

Conclusion: Anesthetic management with GA or CS during MT had no differential impact on the functional outcomes and mortality at discharge or 3 months after stroke in AIS patients, but CS led to more stable hemodynamics and lower incidence of pneumonia.

Pathophysiological and clinical considerations in the perioperative care of patients with a previous ischaemic stroke: a multidisciplinary narrative review

With an ageing population and increasing incidence of cerebrovascular disease, an increasing number of patients presenting for routine and emergency surgery have a prior history of stroke. This presents a challenge for pre-, intra-, and postoperative management as the neurological risk is considerably higher. Evidence is lacking around anaesthetic practice for patients with vascular neurological vulnerability. Through understanding the pathophysiological changes that occur after stroke, insight into the susceptibilities of the cerebral vasculature to intrinsic and extrinsic factors can be developed. Increasing understanding of post-stroke systemic and cerebral haemodynamics has provided improved outcomes from stroke and more robust secondary prevention, although this knowledge has yet to be applied to our delivery of anaesthesia in those with prior stroke. This review describes the key pathophysiological and clinical considerations that inform clinicians providing perioperative care for patients with a prior diagnosis of stroke.

Anesthetic Management of Emergency Endovascular Thrombectomy for Acute Ischemic Stroke, Part 1: Patient Characteristics, Determinants of Effectiveness, and Effect of Blood Pressure on Outcome

In the United States, stroke ranks fifth among all causes of death and is the leading cause of serious long-term disability. The 2018 American Heart Association stroke care guidelines consider endovascular thrombectomy to be the standard of care for patients who have acute ischemic stroke in the anterior circulation when arterial puncture can be made within 6 hours of symptom onset or within 6-24 hours of symptom onset when specific eligibility criteria are satisfied. The aim of this 2-part review is to provide practical perspective on the clinical literature regarding anesthesia care of patients treated with endovascular thrombectomy. Part 1 (this article) reviews the development of endovascular thrombectomy and the determinants of endovascular thrombectomy effectiveness irrespective of method of anesthesia. The first aim of part 1 is to explain why rapid workflow and maintenance of blood pressure are necessary to help support the ischemic brain until, as a result of endovascular thrombectomy, reperfusion is accomplished. The second aim of part 1, understanding the nonanesthesia factors determining endovascular thrombectomy effectiveness, is necessary to identify numerous biases present in observational reports regarding anesthesia for endovascular thrombectomy. With this background, in part 2 (the companion to this article), the observational literature is briefly summarized, largely to identify its weaknesses, but also to develop hypotheses derived from it that have been recently tested in 3 randomized clinical trials of sedation versus general anesthesia for endovascular thrombectomy. In part 2, these 3 trials are reviewed both from a functional outcomes perspective (meta-analysis) and a methodological perspective, providing specifics regarding anesthesia and hemodynamic management. Part 2 concludes with a pragmatic approach to anesthesia decision making (sedation versus general anesthesia) and acute phase anesthesia management of patients treated with endovascular thrombectomy.

Anesthetic Management of Emergency Endovascular Thrombectomy for Acute Ischemic Stroke, Part 2: Integrating and Applying Observational Reports and Randomized Clinical Trials

The 2018 American Heart Association stroke care guidelines consider endovascular thrombectomy to be the standard of care for patients who have acute ischemic stroke in the anterior circulation when arterial puncture can be made: (1) within 6 h of symptom onset; or (2) within 6-24 h of symptom onset when specific eligibility criteria are satisfied. The aim of this 2-part review is to provide practical perspective on the clinical literature regarding anesthesia care of endovascular thrombectomy patients. In the preceding companion article (part 1), the rationale for rapid workflow and maintenance of blood pressure before reperfusion were reviewed. Also in part 1, the key patient and procedural factors determining endovascular thrombectomy effectiveness were identified. In this article (part 2), the observational literature regarding anesthesia for endovascular thrombectomy is summarized briefly, largely to identify its numerous biases, but also to develop hypotheses regarding sedation versus general anesthesia pertaining to workflow, hemodynamic management, and intra- and post-endovascular thrombectomy adverse events. These hypotheses underlie the conduct and outcome measures of 3 recent randomized clinical trials of sedation versus general anesthesia for endovascular thrombectomy. A meta-analysis of functional outcomes from these 3 trials show, when managed according to trial protocols, sedation and general anesthesia result in outcomes that are not significantly different. Details regarding anesthesia and hemodynamic management from these 3 trials are provided. This article concludes with a pragmatic approach to real-time anesthesia decision-making (sedation versus general anesthesia) and the goals and methods of acute phase anesthesia management of endovascular thrombectomy patients.

Assessment of Anesthesia Practice Patterns for Endovascular Therapy for Acute Ischemic Stroke: A Society for Neuroscience in Anesthesiology and Critical Care (SNACC) Member Survey

BACKGROUND

The choice of general anesthesia (GA) or conscious sedation (CS) may impact neurological outcomes of patients undergoing endovascular therapy (EVT) for acute ischemic stroke (AIS). The aim of this survey was to describe the practice patterns of members of the Society for Neuroscience in Anesthesiology and Critical Care (SNACC) for anesthetic management of AIS.

METHODS

Following institutional review board approval, a 16-question online survey assessing anesthetic management of patients with AIS undergoing EVT was circulated to members of SNACC.

RESULTS

A total of 76 SNACC members from 52 institutions and 11 countries completed the survey (12.5% response rate). Overall, 33% of institutions reported dedicated neuroanesthesia teams for EVT. Patients treated with GA ranged from 5% to 100% between centers. In total 51% and 49% of centers in the United States reported preferentially providing GA and CS, respectively, compared with 34% and 66%, respectively, in European centers. Reported anesthetic induction agents are propofol (64%), etomidate (4%) and either medication (33%). For maintenance of GA, volatile anesthetic is used more often (54%) than propofol (16%). There was wide variation in medications used for CS. Arterial catheter placement was reported by 75% and 43% of respondents for patients undergoing GA and CS, respectively. Systolic blood pressure >140 mm Hg was targeted by 35.7% of respondents, with others targeting mean arterial pressure within 10%, 20% or 30% of baseline values. Phenylephrine and norepinephrine were the most commonly used vasopressors.

CONCLUSIONS

There is wide variation in anesthesia technique and hemodynamic management during EVT for AIS, and no consensus on the choice of, or preferred medications for, GA or CS, or target blood pressure and management of hypotension during the procedure.

A 10% blood pressure drop from baseline during mechanical thrombectomy for stroke is strongly associated with worse neurological outcomes

Background

Mechanical thrombectomy (MT) for acute ischemic stroke can be performed under local anesthesia, with or without conscious sedation (CS), or under general anesthesia (GA). The hemodynamic consequence of anesthetic drugs may explain why GA may be associated with worse outcomes. We evaluated the association between hypotension duration during MT and the 90 day functional outcome under both anesthetic regimens.

Methods

Patients were included in this retrospective study if they had an ischemic stroke treated by MT under GA or CS. The main exposure variable was the time below 90% of the reference value of arterial pressure measured before MT. The primary outcome was poor functional outcome defined as a 90 day modified Rankin Score ≥3.

Results

371 patients were included in the study. GA was performed in 42%. A linear association between the duration of arterial hypotension and outcome was observed. The odds ratio for poor functional outcome of 10 min under 90% of the baseline mean arterial pressure was 1.13 (95% CI 1.06 to 1.21) without adjustment and 1.11 (95% CI 1.02 to 1.21) after adjustment for confounding factors. The functional outcome was poorer for patients treated under GA compared with CS, but the association with the depth of hypotension remained similar under both conditions.

Conclusion

In this study, we observed a linear association between the duration of hypotension during MT and the functional outcome at 90 days. An aggressive and personalized strategy for the treatment of hypotension should be considered. Further trials should be conducted to address this question.

Effect of General Anesthesia and Conscious Sedation During Endovascular Therapy on Infarct Growth and Clinical Outcomes in Acute Ischemic Stroke: A Randomized Clinical Trial

Importance

Endovascular therapy (EVT) is the standard of care for select patients who had a stroke caused by a large vessel occlusion in the anterior circulation, but there is uncertainty regarding the optimal anesthetic approach during EVT. Observational studies suggest that general anesthesia (GA) is associated with worse outcomes compared with conscious sedation (CS).

Objective

To examine the effect of type of anesthesia during EVT on infarct growth and clinical outcome.

Design, Setting, and Participants

The General or Local Anesthesia in Intra Arterial Therapy (GOLIATH) trial was a single-center prospective, randomized, open-label, blinded end-point evaluation that enrolled patients from March 12, 2015, to February 2, 2017. Although the trial screened 1501 patients, it included 128 consecutive patients with acute ischemic stroke caused by large vessel occlusions in the anterior circulation within 6 hours of onset; 1372 patients who did not fulfill inclusion criteria and 1 who did not provide consent were excluded. Primary analysis was unadjusted and according to the intention-to-treat principle.

Interventions

Patients were randomized to either the GA group or the CS group (1:1 allocation) before EVT.

Main Outcomes and Measures

The primary end point was infarct growth between magnetic resonance imaging scans performed before EVT and 48 to 72 hours after EVT. The hypothesis formulated before data collection was that patients who were under CS would have less infarct growth.

Results

Of 128 patients included in the trial, 65 were randomized to GA, and 63 were randomized to CS. For the entire cohort, the mean (SD) age was 71.4 (11.4) years, and 62 (48.4%) were women. Baseline demographic and clinical variables were balanced between the GA and CS treatment arms. The median National Institutes of Health Stroke Scale score was 18 (interquartile range [IQR], 14-21). Four patients (6.3%) in the CS group were converted to the GA group. Successful reperfusion was significantly higher in the GA arm than in the CS arm (76.9% vs 60.3%; P = .04). The difference in the volume of infarct growth among patients treated under GA or CS did not reach statistical significance (median [IQR] growth, 8.2 [2.2-38.6] mL vs 19.4 [2.4-79.0] mL; P = .10). There were better clinical outcomes in the GA group, with an odds ratio for a shift to a lower modified Rankin Scale score of 1.91 (95% CI, 1.03-3.56).

Conclusions and Relevance

For patients who underwent thrombectomy for acute ischemic stroke caused by large vessel occlusions in the anterior circulation, GA did not result in worse tissue or clinical outcomes compared with CS.

Trial Registration

clinicaltrials.gov Identifier: NCT02317237.

[Modern principles of neurocritical care]

Neurological diseases frequently demanding admittance to a dedicated neurological intensive care unit (neurocritical care) comprise space-occupying ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, status epilepticus, bacterial meningitis, myasthenic crisis and Guillain-Barré syndrome. Due to often necessary analgesia, sedation and mechanical ventilation, neuromonitoring should ideally be employed. This consists of bedside invasive and non-invasive methods for monitoring cerebral perfusion, oxygenation, metabolism and neurophysiology. Modern treatment principles in neurocritical care mainly aim at avoiding or attenuating secondary neurological brain damage, in particular directed at sufficient perfusion and oxygenation. These include measures such as neuroprotective ventilation, stabilization of the circulation, decreasing intracranial pressure in brain edema and space-occupying processes, anticonvulsive treatment, temperature management and targeted disease-specific treatment.

Acute ischaemic stroke: challenges for the intensivist

PURPOSE

To provide an update about the rapidly developing changes in the critical care management of acute ischaemic stroke patients.

METHODS

A narrative review was conducted in five general areas of acute ischaemic stroke management: reperfusion strategies, anesthesia for endovascular thrombectomy, intensive care unit management, intracranial complications, and ethical considerations.

RESULTS

The introduction of effective reperfusion strategies, including IV thrombolysis and endovascular thrombectomy, has revolutionized the management of acute ischaemic stroke and transformed outcomes for patients. Acute therapeutic efforts are targeted to restoring blood flow to the ischaemic penumbra before irreversible tissue injury has occurred. To optimize patient outcomes, secondary insults, such as hypotension, hyperthermia, or hyperglycaemia, that can extend the penumbral area must also be prevented or corrected. The ICU management of acute ischaemic stroke patients, therefore, focuses on the optimization of systemic physiological homeostasis, management of intracranial complications, and neurological and haemodynamic monitoring after reperfusion therapies. Meticulous blood pressure management is of central importance in improving outcomes, particularly in patients that have undergone reperfusion therapies.

CONCLUSIONS

While consensus guidelines are available to guide clinical decision making after acute ischaemic stroke, there is limited high-quality evidence for many of the recommended interventions. However, a bundle of medical, endovascular, and surgical strategies, when applied in a timely and consistent manner, can improve long-term stroke outcomes.

Decreases in Blood Pressure During Thrombectomy Are Associated With Larger Infarct Volumes and Worse Functional Outcome

Background and Purpose- After large-vessel intracranial occlusion, the fate of the ischemic penumbra, and ultimately final infarct volume, largely depends on tissue perfusion. In this study, we evaluated whether blood pressure reduction and sustained relative hypotension during endovascular thrombectomy are associated with infarct progression and functional outcome. Methods- We identified consecutive patients with large-vessel intracranial occlusion ischemic stroke who underwent mechanical thrombectomy at 2 comprehensive stroke centers. Intraprocedural mean arterial pressure (MAP) was monitored throughout the procedure. ΔMAP was calculated as the difference between admission MAP and lowest MAP during endovascular thrombectomy until recanalization. Sustained hypotension was measured as the area between admission MAP and continuous measurements of intraprocedural MAP (aMAP). Final infarct volume was measured using magnetic resonance imaging at 24 hours, and functional outcome was assessed using the modified Rankin Scale at discharge and 90 days. Associations with outcome were analyzed using linear and ordinal multivariable logistic regression. Results- Three hundred ninety patients (mean age 71±14 years, mean National Institutes of Health Stroke Scale score of 17) were included in the study; of these, 280 (72%) achieved Thrombolysis in Cerebral Infarction 2B/3 reperfusion. Eighty-seven percent of patients experienced MAP reductions during endovascular thrombectomy (mean 31±20 mm Hg). ΔMAP was associated with greater infarct growth ( P=0.036) and final infarct volume ( P=0.035). Mean ΔMAP among patients with favorable outcomes (modified Rankin Scale score, 0-2) was 20±21 mm Hg compared with 30±24 mm Hg among patients with poor outcome ( P=0.002). In the multivariable analysis, ΔMAP was independently associated with higher (worse) modified Rankin Scale scores at discharge (adjusted odds ratio per 10 mm Hg, 1.17; 95% CI, 1.04-1.32; P=0.009) and at 90 days (adjusted odds ratio per 10 mm Hg, 1.22; 95% CI, 1.07-1.38; P=0.003). The association between aMAP and outcome was also significant at discharge ( P=0.002) and 90 days ( P=0.001). Conclusions- Blood pressure reduction before recanalization is associated with larger infarct volumes and worse functional outcomes for patients affected by large-vessel intracranial occlusion stroke. These results underscore the importance of BP management during endovascular thrombectomy and highlight the need for further investigation of blood pressure management after large-vessel intracranial occlusion stroke.

Cognitive Aids for the Diagnosis and Treatment of Neuroanesthetic Emergencies: Consensus Guidelines on Behalf of the Society for Neuroscience in Anesthesiology and Critical Care (SNACC) Education Committee

Cognitive aids and evidence-based checklists are frequently utilized in complex situations across many disciplines and sectors. The purpose of such aids is not simply to provide instruction so as to fulfill a task, but rather to ensure that all contingencies related to the emergency are considered and accounted for and that the task at hand is completed fully, despite possible distractions. Furthermore, utilization of a checklist enhances communication to all team members by allowing all stakeholders to know and understand exactly what is occurring, what has been accomplished, and what remains to be done. Here we present a set of evidence-based critical event cognitive aids for neuroanesthesia emergencies developed by the Society for Neuroscience in Anesthesiology and Critical Care (SNACC) Education Committee.

Endovascular Therapy for Acute Ischemic Stroke: A Comprehensive Review of Current Status

Stroke remains among the leading causes of disability and death worldwide. Fibrinolytic therapy is associated with poor patency and functional outcomes. Recently, multiple randomized trials have been published that have consolidated the role of endovascular therapy for ischemic stroke due to large vessel occlusion in the anterior cerebral circulation. This manuscript reviews the current understanding of the endovascular management of acute stroke including technical aspects and current evidence base.

Role of anesthesia in endovascular stroke therapy

PURPOSE OF REVIEW

Recent randomized clinical trials have demonstrated strong efficacy of endovascular therapy (EVT) for acute ischemic stroke (AIS) from large vessel occlusions; in the USA alone, tens of thousands of patients annually may benefit. The impact of the type of anesthesia used during mechanical thrombectomy on patient outcomes remains controversial. This review discusses the current literature on the effects of anesthesia type on patient outcome following endovascular stroke therapy.

RECENT FINDINGS

EVT is the standard of treatment for intracranial large vessel occlusions. Recent studies show that general anesthesia is associated with negative clinical outcome in AIS patients undergoing EVT. Two of the possible mechanisms of this finding are systolic hypotension and hypocapnia. However, the only published randomized controlled studies to date, sedation vs. intubation for endovascular stroke treatment and anesthesia during stroke showed no difference in short-term clinical outcome between EVT patients treated with general anesthesia and conscious sedation and improved longer-term outcome in the general anesthesia group.

SUMMARY

Retrospective reports, and the 2015 American Heart Association/American Stroke Association Guideline (focused update of the 2013 guidelines for the early management of patients with AIS regarding endovascular treatment) based on these reports, are in favor of sedation (conscious sedation) over general anesthesia for endovascular stroke thrombectomy. However, the two randomized controlled prospective studies published provide inconclusive evidence as to the best anesthetic practice for endovascular stroke therapy. More randomized clinical trials are needed to optimize anesthetic patient care in AIS.

Anaesthesia for neuroradiology: thrombectomy: 'one small step for man, one giant leap for anaesthesia'

PURPOSE OF REVIEW

Endovascular management of acute thrombotic strokes is a new management technique. Anaesthesia will play a key role in the management of these patients. To date there is no established method of managing these patients from an anaesthetic perspective.

RECENT FINDINGS

In 2015, five landmark studies popularized intra-arterial clot retrieval for ischaemic strokes. Since then there have been a number of small studies investigating the best anaesthetic technique, taking into account patient, technical, and clinical factors. This review summarizes these studies and discusses the different anaesthetic options, with their relative merits and pitfalls.

SUMMARY

There is a paucity of robust evidence for the best anaesthetic practice in this cohort of patients. Airway protection seems to be an issue in 2.5% of cases. Timing of the procedure is vital, and any delay may be detrimental to neurological outcome. In a survey of neurointerventionalists, the main concern they expressed was the potential delay to revascularization posed by anaesthesia. Patients complain of pain during mechanical clot retrieval if awake. The overall consensus seems to be favouring conscious sedation over general anaesthesia in the acute setting.

National survey on perioperative anaesthetic management in the endovascular treatment of acute ischaemic stroke

OBJECTIVE

To assess the anaesthetic management of treatment for endovascular acute ischaemic stroke (AIS) in Spain.

MATERIALS AND METHOD

A survey was designed by the SEDAR Neuroscience Section and sent to the Spanish anaesthesiology departments with a primary stroke centre between July and November 2016.

RESULTS

Of the 47 hospitals where endovascular treatment of AIS is performed, 37 anaesthesiology departments participated. Thirty responses were obtained; three of which were eliminated due to duplication (response rate of 72.9%). Health coverage for AIS endovascular treatment was available 24hours a day in 63% of the hospitals. The anaesthesiologist in charge of the procedure was physically present in the hospital in 55.3%. There was large inter-hospital variability in non-standard monitoring and type of anaesthesia. The most important criterion for selecting type of anaesthesia was multidisciplinary choice made by the anaesthesiologist, neurologist and neuroradiologist (59.3%). The duration of time from arrival to arterial puncture was 10-15minutes in 59.2%. In 44.4%, systolic blood pressure was maintained between 140-180mmHg, and diastolic blood pressure<105mmHg. Glycaemic levels were taken in 81.5% of hospitals. Intravenous heparinisation was performed during the procedure in 66.7% with different patterns of action. In cases of moderate neurological deterioration with no added complications, 85.2% of the included hospitals awakened and extubated the patients.

CONCLUSIONS

The wide variability observed in the anaesthetic management and the organization of the endovascular treatment of AIS demonstrates the need to create common guidelines for anaesthesiologists in Spain.

Comparison of Noninvasive High-Intensity Focused Ultrasound with Radiofrequency Ablation of Osteoid Osteoma

OBJECTIVE

To evaluate clinical feasibility and safety of magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) treatment of symptomatic osteoid osteoma and to compare clinical response with standard of care treatment.

STUDY DESIGN

Nine subjects with radiologically confirmed, symptomatic osteoid osteoma were treated with MR-HIFU in an institutional review board-approved clinical trial. Treatment feasibility and safety were assessed. Clinical response was evaluated in terms of analgesic requirement, visual analog scale pain score, and sleep quality. Anesthesia, procedure, and recovery times were recorded. This MR-HIFU group was compared with a historical control group of 9 consecutive patients treated with radiofrequency ablation.

RESULTS

Nine subjects (7 male, 2 female; 16 ± 6 years) were treated with MR-HIFU without technical difficulties or any serious adverse events. There was significant decrease in their median pain scores 4 weeks within treatment (6 vs 0, P < .01). Total pain resolution and cessation of analgesics were achieved in 8 of 9 patients after 4 weeks. In the radiofrequency ablation group, 9 patients (8 male, 1 female; 10 ± 6 years) were treated in routine clinical practice. All 9 demonstrated complete pain resolution and cessation of medications by 4 weeks with a significant decrease in median pain scores (9 vs 0, P < .001). One developed a second-degree skin burn, but there were no other adverse events. Procedure times and treatment charges were comparable between the 2 groups.

CONCLUSION

This pilot study shows that MR-HIFU treatment of osteoid osteoma refractory to medical therapy is feasible and can be performed safely in pediatric patients. Clinical response is comparable with standard of care treatment but without any incisions or exposure to ionizing radiation.

TRIAL REGISTRATION

ClinicalTrials.govNCT02349971.

Challenges in the Anesthetic and Intensive Care Management of Acute Ischemic Stroke

Acute ischemic stroke (AIS) is a devastating condition with high morbidity and mortality. In the past 2 decades, the treatment of AIS has been revolutionized by the introduction of several interventions supported by class I evidence-care on a stroke unit, intravenous tissue plasminogen activator within 4.5 hours of stroke onset, aspirin commenced within 48 hours of stroke onset, and decompressive craniectomy for supratentorial malignant hemispheric cerebral infarction. There is new class I evidence also demonstrating benefits of endovascular therapy on functional outcomes in those with anterior circulation stroke. In addition, the importance of the careful management of key systemic physiological variables, including oxygenation, blood pressure, temperature, and serum glucose, has been appreciated. In line with this, the role of anesthesiologists and intensivists in managing AIS has increased. This review highlights the main challenges in the endovascular and intensive care management of AIS that, in part, result from the paucity of research focused on these areas. It also provides guidelines for the management of AIS based upon current evidence, and identifies areas for further research.

Mechanical thrombectomy in acute stroke - Five years of experience in Poland

OBJECTIVES

Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland.

METHODS AND RESULTS

We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures.

RESULTS

Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250±99min. 90.3% of the studied patients had MT within 6h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% - emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b-TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization - in 30.7%, mRS of 0-2 - in 31.4% and mRS of 6 in 22% of cases.

CONCLUSION

Our results can help harmonize standards for MT in Poland according to international guidelines.

Airway management and mechanical ventilation in acute brain injury

Patients with acute neurologic disease often develop respiratory failure, the management of which profoundly affects brain physiology and long-term functional outcomes. This chapter reviews airway management and mechanical ventilation of patients with acute brain injury, offering practical strategies to optimize treatment of respiratory failure and minimize secondary brain injury. Specific concerns that are addressed include physiologic changes during intubation and ventilation such as the effects on intracranial pressure and brain perfusion; cervical spine management during endotracheal intubation; the role of tracheostomy; and how ventilation and oxygenation are utilized to minimize ischemia-reperfusion injury and cerebral metabolic distress.

Mechanical Thrombectomy in Acute Ischemic Stroke: Initial Single-Center Experience and Comparison with Randomized Controlled Trials

BACKGROUND

Until recently, intravenous thrombolysis was the only reperfusion therapy with proven efficacy in patients with acute ischemic stroke. However, this treatment option has low recanalization rates in large-vessel occlusions. The search for additional treatments continued until 5 randomized trials (MR CLEAN, ESCAPE, EXTEND-IA, SWIFT PRIME, and REVASCAT) revealed the superiority of mechanical thrombectomy for anterior circulation large-vessel occlusion. After 1 year of performing thrombectomy with stent retrievers in our tertiary hospital, we intended to answer the question: is it possible to achieve similar results in a "real-world" setting?

METHODS

We analyzed data from our prospective observational registry, compared it with the trials aforementioned, and concluded that the answer is affirmative.

RESULTS

Our study population of 77 patients, with a mean age of 68,2 years and 48,1% men, is comparable with these trials in much of selection criteria, baseline characteristics, and rate of previous intravenous thrombolysis (72,7%). Recovery of functional independence at 90 days was achieved in almost two thirds of patients, similarly to the referred trials. We devoted special emphasis on fast recanalization, keeping a simple image selection protocol (based on non-enhanced and computed tomography angiography) and not waiting for clinical response to thrombolysis in patients eligible for mechanical thrombectomy. We emphasize a successful recanalization rate of 87% and only 2,6% symptomatic intracranial hemorrhage.

CONCLUSION

In summary, mechanical thrombectomy seems to be a safe and effective treatment option in a "real-world" scenario, with results similar to those of the recent randomized controlled trials.

[Management of anesthesia in endovascular interventions]

Cardiovascular diseases are one of the leading causes of morbidity and mortality in Germany. In these patients, the high-risk profile necessitates an interdisciplinary and multimodal approach to treatment. Endovascular interventions and vascular surgery have become established as an important element of this strategy in the past; however, the different anatomical localizations of pathological vascular alterations make it necessary to use a wide spectrum of procedural options and methods; therefore, the requirements for management of anesthesia are variable and necessitate a differentiated approach. Endovascular procedures can be carried out with the patient under general or regional anesthesia (RA); however, in the currently available literature there is no evidence for an advantage of RA over general anesthesia regarding morbidity and mortality, although a reduction in pulmonary complications could be found for some endovascular interventions. Epidural and spinal RA procedures should be carefully considered with respect to the risk-benefit ratio and consideration of the recent guidelines on anesthesia against the background of the current study situation and the regular use of therapy with anticoagulants. The following article elucidates the specific characteristics of anesthesia management as exemplified by some selected endovascular interventions.

Even Small Decreases in Blood Pressure during Conscious Sedation Affect Clinical Outcome after Stroke Thrombectomy: An Analysis of Hemodynamic Thresholds

BACKGROUND AND PURPOSE

The adverse effects of general anesthesia in stroke thrombectomy have been attributed to intraprocedural hypotension, yet optimal hemodynamic targets remain elusive. Identifying hemodynamic thresholds from patients without exposure to general anesthesia may help separate the effect of hypotension from the effect of anesthesia in thrombectomy outcomes. Therefore, we investigated which hemodynamic parameters and targets best correlate with outcome in patients treated under sedation with monitored anesthesia care.

MATERIALS AND METHODS

We performed a retrospective analysis of a prospectively collected data base of patients with anterior circulation stroke who were successfully reperfused (modified TICI ≥ 2b) under monitored anesthesia care sedation from 2010 to 2015. Receiver operating characteristic curves were generated for the lowest mean arterial pressure before reperfusion, both as absolute values and relative changes from baseline. Cutoffs were tested in binary logistic regression models of poor outcome (90-day mRS > 2).

RESULTS

Two-hundred fifty-six of 714 patients met the inclusion criteria. In a multivariable model, a ≥10% mean arterial pressure decrease from baseline had an OR for poor outcome of 4.38 (95% CI, 1.53-12.56; P < .01). Other models revealed that any mean pressure of <85 mm Hg before reperfusion had an OR for poor outcome of 2.22 (95% CI, 1.09-4.55; P = .03) and that every 10-mm Hg drop in mean arterial pressure below 100 mm Hg had an OR of 1.28 (95% CI, 1.01-1.62; P = .04).

CONCLUSIONS

A ≥10% mean arterial pressure drop from baseline is a strong risk factor for poor outcome in a homogeneous population of patients with stroke undergoing thrombectomy under sedation. This threshold could guide hemodynamic management of patients during sedation and general anesthesia.

Anesthesia for Endovascular Approaches to Acute Ischemic Stroke

Involvement of the Anesthesiologist in the early stages of care for acute ischemic stroke patient undergoing endovascular treatment is essential. Anesthetic management includes the anesthetic technique (general anesthesia vs sedation), a matter of much debate and an area in need of well-designed prospective studies. The large numbers of confounding factors make the design of such studies a difficult process. A universally agreed point in the endovascular management of acute ischemic stroke is the importance of decreasing the time to revascularization. Hemodynamic and ventilatory management and implementation of neuroprotective modalities and treatment of acute procedural complications are important components of the anesthetic plan.

[Technical standards for the interventional treatment of acute ischemic stroke]

Acute ischemic stroke is the leading cause of acquired disability and its treatment is still a major challenge. For more than a decade, various mechanical devices have been developed for the recanalization of proximal artery occlusions in acute ischemic stroke but most of them have been approved for clinical use, only on the basis of uncontrolled case series. Intravenous thrombolysis with recombinant tissue-specific plasminogen activator administered (iv rtPA) within 4.5 h of symptom onset is so far the only approved medicinal treatment in the acute phase of cerebral infarction. With the introduction of stent retrievers, mechanical thrombectomy has demonstrated substantial rates of partial or complete arterial recanalization and improved outcomes compared with iv rtPA and best medical treatment alone in multiple randomized clinical trials in select patients with acute ischemic stroke and proximal artery occlusions. This review discusses the evolution of endovascular stroke therapy followed by a discussion of the current technical standards of mechanical thrombectomy that have to be considered during endovascular stroke therapy and the updated treatment recommendations of the ESO Karolinska stroke update.

Anesthetic strategy during endovascular therapy: General anesthesia or conscious sedation? (GOLIATH - General or Local Anesthesia in Intra Arterial Therapy) A single-center randomized trial

RATIONALE

Endovascular therapy after acute ischemic stroke due to large vessel occlusion is now standard of care. There is equipoise as to what kind of anesthesia patients should receive during the procedure. Observational studies suggest that general anesthesia is associated with worse outcomes compared to conscious sedation. However, the findings may have been biased. Randomized clinical trials are needed to determine whether the choice of anesthesia may influence outcome.

AIM AND HYPOTHESIS

The objective of GOLIATH (General or Local Anestesia in Intra Arterial Therapy) is to examine whether the choice of anesthetic regime during endovascular therapy for acute ischemic stroke influence patient outcome. Our hypothesis is that that conscious sedation is associated with less infarct growth and better functional outcome.

METHODS

GOLIATH is an investigator-initiated, single-center, randomized study. Patients with acute ischemic stroke, scheduled for endovascular therapy, are randomized to receive either general anesthesia or conscious sedation.

STUDY OUTCOMES

The primary outcome measure is infarct growth after 48-72 h (determined by serial diffusion-weighted magnetic resonance imaging). Secondary outcomes include 90-day modified Rankin Scale score, time parameters, blood pressure variables, use of vasopressors, procedural and anesthetic complications, success of revascularization, radiation dose, and amount of contrast media.

DISCUSSION

Choice of anesthesia may influence outcome in acute ischemic stroke patients undergoing endovascular therapy. The results from this study may guide future decisions regarding the optimal anesthetic regime for endovascular therapy. In addition, this study may provide preliminary data for a multicenter randomized trial.

Cerebral protection during neurosurgery and stroke

PURPOSE OF REVIEW

This article reviews the recent evidence on perioperative neuroprotection in patients undergoing brain surgery and in patients with acute stroke.

RECENT FINDINGS

With varying degrees of success, numerous pharmacological and nonpharmacological therapies have been employed to provide neuroprotection for patients during the perioperative period and after acute ischemic stroke (IAS). Recent studies have failed to demonstrate neuroprotective effects of intraoperative remifentanil or propofol use, although hypertonic saline may provide better brain relaxation than mannitol during elective intracranial surgery for tumor. Magnesium sulfate offers no improvement in neurological outcome at 90 days after stroke. Medical management alone may be superior to medical management with interventional therapy for the prevention of death or stroke in unruptured arteriovenous malformations. In patients with IAS with a proximal vessel occlusion, small infarct core, and moderate-to-good collateral circulation, rapid endovascular treatment resulted in improved functional outcomes and reduced mortality. For endovascular clot evacuation after IAS, conscious sedation may be safer than general anaesthesia.

SUMMARY

Recent evidence provides insufficient evidence of neuroprotective strategies to guide clinical management, and more randomized clinical trials are needed to optimize patient care.

Definition, evaluation, and management of brain relaxation during craniotomy

The term 'brain relaxation' is routinely used to describe the size and firmness of the brain tissue during craniotomy. The status of brain relaxation is an important aspect of neuroanaesthesia practice and is relevant to the operating conditions, retraction injury, and likely patient outcomes. Brain relaxation is determined by the relationship between the volume of the intracranial contents and the capacity of the intracranial space (i.e. a content-space relationship). It is a concept related to, but distinct from, intracranial pressure. The evaluation of brain relaxation should be standardized to facilitate clinical communication and research collaboration. Both advantageous and disadvantageous effects of the various interventions for brain relaxation should be taken into account in patient care. The outcomes that matter the most to patients should be emphasized in defining, evaluating, and managing brain relaxation. To date, brain relaxation has not been reviewed specifically, and the aim of this manuscript is to discuss the current approaches to the definition, evaluation, and management of brain relaxation, knowledge gaps, and targets for future research.

Carotid stent-assisted thrombectomy in acute ischemic stroke

Acute carotid occlusion or near-occlusion with concomitant intracranial embolism cause severe acute ischemic strokes in patients. These concomitant occlusions have suggested poor response to intravenous thrombolysis and complicate endovascular treatment. Nevertheless, endovascular stent-assisted thrombectomy may improve outcome in patients but the treatment is not without concerns. Required antiplatelet therapy to prevent stent thrombosis may increase the rate of intracranial hemorrhage, especially after recent thrombolysis. Furthermore, technical difficulties in access of the intracranial vasculature may cause adverse events, even in the hands of experienced interventionalists. These concerns currently defy the treatment in being recommended for general use and only on a compassionate basis. However, recent patient series have suggested reasonable safety and efficacy for carotid stent-assisted thrombectomy.

Management of the Interventional Stroke Patient

OPINION STATEMENT

The acute treatment of major ischemic stroke has been revolutionized by strong and consistent evidence from multiple randomized trials. Endovascular treatment by mechanical thrombectomy will be increasingly chosen as an adjunctive or alternative to intravenous thrombolysis. To apply this form of stroke treatment is associated with the challenge of optimal periinterventional treatment. The patient has to be identified, counselled, prepared, monitored, cardiovascularly stabilized, possibly sedated and ventilated, and postprocedurally treated in the optimal way. However, most aspects of periinterventional treatment have as yet not been clarified and require prospective research. Among these, the question of general anesthesia vs conscious sedation has received most attention and may be the most crucial one. Based on a great amount of retrospective data, it appears reasonable to start the intervention under conscious sedation of the non-intubated patient with standby measures for emergent intubation, until prospective randomized trials have clarified that issue. Periinterventional management will significantly affect the success of recanalization.

Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome.

Sedation vs. Intubation for Endovascular Stroke TreAtment (SIESTA) – A Randomized Monocentric Trial

Background

The optimal peri-interventional management of sedation and airway for endovascular stroke treatment (EST) appears to be a crucial factor for treatment success. According to retrospective studies, the widely favored general anesthesia with intubation seems to be associated with poor functional outcome compared to a slightly sedated non-intubated condition (conscious sedation).

Method

SIESTA is a monocentric, prospective, randomized parallel-group, open-label treatment trial with blinded endpoint evaluation (PROBE design). The study compares the non-intubated with the intubated state in patients receiving endovascular treatment of acute ischemic anterior circulation stroke. The primary endpoint is early neurological improvement as by National Institutes of Health Stroke Scale (NIHSS) after 24 h (difference between NIHSS on admission and NIHSS after 24 h). Secondary endpoints include: functional outcome after three-months as by modified Rankin Scale (mRS), mortality, parameters of ventilation and critical care, feasibility, and safety, i.e. complications related to endovascular stroke treatment.

Conclusion

The aims of this study are to prospectively clarify whether the non-intubated state of conscious sedation is feasible, safe, and superior with regard to early neurological improvement compared to the intubated state of general anesthesia in patients receiving acute endovascular stroke treatment.