Alejandro Rabinstein

Conscious Sedation versus General Anesthesia during Endovascular Acute Ischemic Stroke Treatment: A Systematic Review and Meta-Analysis

Nine studies encompassing nearly 2000 patients treated with or without anesthesia for acute stroke were analyzed. Patients with acute ischemic stroke undergoing intra-arterial therapy may have worse outcomes with general anesthesia compared with conscious sedation. However, the difference in stroke severity at the onset may confound the comparison in the available studies. BACKGROUND AND PURPOSE: A number of studies have suggested that anesthesia type (conscious sedation versus general anesthesia) during intra-arterial treatment for acute ischemic stroke has implications for patient outcomes. We performed a systematic review and meta-analysis of studies comparing the clinical and angiographic outcomes of the 2 anesthesia types. MATERIALS AND METHODS: In March 2014, we conducted a computerized search of MEDLINE and EMBASE for reports on anesthesia and endovascular treatment of acute ischemic stroke. Using random-effects meta-analysis, we evaluated the following outcomes: recanalization rate, good functional outcome (mRS ≤ 2), asymptomatic and symptomatic intracranial hemorrhage, death, vascular complications, respiratory complications, procedure time, time to groin, and time from symptom onset to recanalization. RESULTS: Nine studies enrolling 1956 patients (814 with general anesthesia and 1142 with conscious sedation) were included. Compared with patients treated by using conscious sedation during stroke intervention, patients undergoing general anesthesia had higher odds of death (OR = 2.59; 95% CI, 1.87–3.58) and respiratory complications (OR = 2.09; 95% CI, 1.36–3.23) and lower odds of good functional outcome (OR = 0.43; 95% CI, 0.35–0.53) and successful angiographic outcome (OR = 0.54; 95% CI, 0.37–0.80). No difference in procedure time (P = .28) was seen between the groups. Preintervention NIHSS scores were available from 6 studies; in those, patients receiving general anesthesia had a higher average NIHSS score. CONCLUSIONS: Patients with acute ischemic stroke undergoing intra-arterial therapy may have worse outcomes with general anesthesia compared with conscious sedation. However, the difference in stroke severity at the onset may confound the comparison in the available studies; thus, a randomized trial is necessary to confirm this association.

Age-Related Trends in the Treatment and Outcomes of Ruptured Cerebral Aneurysms: A Study of the Nationwide Inpatient Sample 2001–2009

BACKGROUND AND PURPOSE: Patient age substantially influences treatment decisions for ruptured cerebral aneurysms. It would be useful to understand national age-related trends of treatment techniques and outcomes in patients treated for ruptured cerebral aneurysm in the United States. MATERIALS AND METHODS: Using the US Nationwide Inpatient Sample, we evaluated trends in treatment technique (clipping versus coiling) and discharge status of patients undergoing clipping or coiling of ruptured cerebral aneurysms between 2001 and 2009. Outcomes were evaluated in relation to 4 age strata: 1) younger than 50 years of age, 2) 50–64 years of age, 3) 65–79 years of age, and 4) patients 80 years or older. We compared outcomes between treatment groups for patients treated between 2001–2004 with those treated between 2005–2009. RESULTS: A significant increase in the proportion of patients undergoing endovascular coiling between 2001 and 2009 was noted for all age groups (P < .0001). For both clipped and coiled patients, mortality and the proportion of patients discharged to long-term facilities increased with age. Overall mortality for patients clipped and coiled decreased modestly for all age groups, and overall proportions of patients discharged home increased modestly (P < .01) for all age groups except those older than 80 years of age. CONCLUSIONS: Between 2001 and 2009, there has been a significant increase in the proportion of patients with ruptured aneurysms undergoing endovascular coiling rather than aneurysm clipping. This increase was more pronounced in older patients. Mortality from aneurysmal subarachnoid hemorrhage decreased during the past decade, regardless of aneurysm treatment technique.

Refractory status epilepticus: new insights in presentation, treatment, and outcome

Abstract Refractory status epilepticus (RSE), defined as status epilepticus that fails to respond to the acute administration of two antiepileptic medications, occurs in approximately a third of patients with status epilepticus, and is associated with increased hospital length of stay, mortality, and functional disability. Common presentations include: (1) generalized convulsive status epilepticus or complex partial status epilepticus that continue despite initial therapies; (2) stupor or coma following a generalized convulsive or complex partial seizure; or (3) stupor or coma following brain surgery or acute brain injury. When status epilepticus continues or recurs 24 hours or more after the initiation of anesthetic therapy, or recurs on the reduction or withdrawal of anesthesia, it is termed super RSE. Published evidence on optimal management of RSE consists largely of case reports or small series. The mainstay of treatment is the administration of anesthetic agents titrated to electrographic seizure control. Adjunctive therapies include hypothermia and immunosuppression and less commonly, surgery, electrical stimulation therapies, and induction of ketosis. Patients with cardiopulmonary complications and prolonged duration of drug-induced coma tend to have worse post-treatment functional outcomes. However, significant improvement over time can occur in survivors, and thus treatment is justified even in patients who require prolonged anesthetic coma. The strongest predictors of outcome are duration of anesthetic coma, etiology, and development of cardiopulmonary complications.

Cardiopulmonary resuscitation in critically ill neurologic-neurosurgical patients

OBJECTIVES To establish the rate of successful cardiopulmonary resuscitation (CPR) and to study outcome predictors in patients who experienced in-hospital cardiac arrest after being admitted to the neurologic-neurosurgical intensive care unit (ICU) with a primary neurologic diagnosis. PATIENTS AND METHODS We identified patients admitted to the neurologic-neurosurgical ICU between 1994 and 2001 who experienced in-hospital cardiac arrest and received CPR. Functional outcome was assessed using the modified Rankin scale. RESULTS During the study period, 38 consecutive patients experienced in-hospital cardiac arrest and received CPR. The median age of the patients was 65 years (range, 16-81 years), and the mean interval from admission to CPR was 12 days (range, 3 hours to 47 days). Acute intracranial disease was present in 32 patients (84%). Twenty-one patients (55%) were in the ICU at the time of the cardiac arrest; cardiac arrests in the wards occurred at a mean interval of 9 days (range, 1-45 days) after ICU discharge. Cardiopulmonary resuscitation achieved return of spontaneous circulation in 23 patients (61%). Seven patients (18%) were discharged from the hospital, 5 of whom later achieved a modified Rankin scale score of 2 or lower. Cardiac arrest after a deteriorating clinical course resulted in uniformly fatal outcomes. Duration of CPR shorter than 5 minutes and CPR in the ICU were associated with survival and good functional recovery. CONCLUSIONS Cardiopulmonary resuscitation is a worthwhile procedure in severely ill neurologic-neurosurgical patients, regardless of the patients age. However, the outcome after CPR appears much worse in patients with a prior deteriorating clinical course.

Clinical Outcomes of Patients with Delayed Diagnosis of Spinal Dural Arteriovenous Fistulas

BACKGROUND AND PURPOSE: Spinal dural arteriovenous fistulas are commonly missed on imaging or misdiagnosed as inflammatory or neoplastic processes. We reviewed a consecutive series of spinal dural arteriovenous fistulas referred to our institution that were missed or misdiagnosed on initial imaging and studied the clinical consequences of missing or misdiagnosing the lesion. MATERIALS AND METHODS: We reviewed spinal dural arteriovenous fistulas diagnosed at our institution between January 1, 2000, and November 1, 2014. A lesion was defined as “misdiagnosed” if initial MR imaging or CT myelography demonstrated characteristic imaging features of spinal dural arteriovenous fistula but the patient was clinically or radiologically misdiagnosed. Outcomes included length of delay of diagnosis, increased disability (increase in mRS or Aminoff motor disability of ≥1 point) between initial imaging evaluation and diagnosis date, and posttreatment disability. RESULTS: Fifty-three consecutive spinal dural arteriovenous fistulas that were initially misdiagnosed despite having characteristic imaging findings on MR imaging or CT myelography were included in our study. Eight patients (18.9%) underwent spinal angiography before referral, which was interpreted as having negative findings but was either incomplete (6 cases) or retrospectively demonstrated the spinal dural arteriovenous fistulas (2 cases). The median time of delayed diagnosis was 6 months (interquartile range, 2–14 months). Fifty-one patients (96.2%) had increased disability between the initial study, which demonstrated features of a spinal dural arteriovenous fistula, and diagnosis. Thirty-two patients (60.4%) developed a new requirement for a walker or wheelchair. Following treatment, 21 patients (41.2%) had an improvement of 1 point on the mRS or Aminoff motor disability scale. CONCLUSIONS: Delayed diagnosis of spinal dural arteriovenous fistula with characteristic imaging features results in high rates of additional disability that are often irreversible despite surgical or endovascular treatment of the fistula.

Weaning from the ventilator using bipap in myasthenia gravis

Weaning from mechanical ventilation is frequently difficult in patients recovering from a myasthenia gravis (MG) crisis.4 Typically, such patients are initially treated with high levels of pressure support ventilation. This ventilatory mode delivers positive pressure at the onset of each inspiration triggered by the patient’s effort. During weaning, these levels of pressure support are gradually reduced. Then, before extubation, patients are connected to a Tpiece (an external tube that allows oxygen delivery through the endotracheal tube) to assess their ventilatory capacity without mechanical support. Often, patients with MG are easily weaned to low levels of pressure support only to reach a standstill. Insufficient respiratory muscle strength may cause these patients to repeatedly fail these T-piece trials and extubation attempts. However, prolonged endotracheal intubation increases the risk of airway damage and ventilator-associated pneumonia.1 Noninvasive bilevel positive airway pressure (BiPAP) ventilation delivers adjustable degrees of positive pressure throughout the respiratory cycle to overcome upper airway resistance during inspiration and prevent alveolar collapse at the end of expiration.2 Pressures are delivered through a close-fitting mask, thus avoiding the need for an endotracheal tube. Because it reduces the work of breathing, BiPAP may be an ideal method of gradual weaning for patients with MG who develop ventilator-dependency. We report our experience using BiPAP as a weaning method in five episodes of respiratory failure occurring in three patients with an exacerbation of MG. The patients were mechanically ventilated due to neuromuscular respiratory failure caused by MG crisis. None had alternative explanations for respiratory failure. All patients had failed repeated T-piece trials and were receiving low levels of pressure support ventilation (inspiratory pressure 10 mm Hg and end-expiratory pressures 8 mm Hg) at the time of extubation and institution of BiPAP support. All had been treated with plasmapheresis in the acute phase and received incremental dosages of pyridostigmine during the weaning process, with improved muscle strength documented by serial neurological examinations. Timing of extubation and institution of BiPAP was based on the clinical judgment of the treating physician. Bedside respiratory function tests and arterial blood gases were not consistently measured before extubation. BiPAP ventilation was well tolerated and prevented reintubation in all cases. Before institution of BiPAP, patients had been intubated for a mean time of 13 days (range, 2–26 days). BiPAP inspiratory pressures ranged from 18 to 8 mm Hg and expiratory pressures from 8 to 4 mm Hg. No cases of pneumonia occurred despite all patients having bulbar weakness. Several days of BiPAP ventilation were needed in most cases (Table 1). Prior experience with BiPAP has largely been in patients with underlying pulmonary disease or with chronic neuromuscular disorders. BiPAP may prevent intubation in selected patients with MG, but its value in weaning from the ventilator has not been previously investigated.3 Weaning trials are subjective and dependent on many factors, mostly physician preferences. However, we found BiPAP use may facilitate weaning and shorten the time that pa-

Are routine intensive care admissions needed after endovascular treatment of unruptured aneurysms

In this series of 200 patients treated for unruptured intracranial aneurysms, 65% were sent to a routine floor instead of the intensive care unit as is commonly done. Only one patient required transfer to the ICU and thus the authors concluded that in patients without significant co-morbidities, intraoperative complications, or complex aneurysms, routine placement in the ICU after embolization is not warranted. SUMMARY: Routine intensive care unit monitoring is common after elective embolization of unruptured intracranial aneurysms. In this series of 200 consecutive endovascular procedures for unruptured intracranial aneurysms, 65% of patients were triaged to routine (non-intensive care unit) floor care based on intraoperative findings, aneurysm morphology, and absence of major co-morbidities. Only 1 patient (0.5%) required subsequent transfer to the intensive care unit for management of a perioperative complication. The authors conclude that patients without major co-morbidities, intraoperative complications, or complex aneurysm morphology can be safely observed in a regular ward rather than being admitted to the intensive care unit.

Early basal ganglia hyperperfusion on CT perfusion in acute ischemic stroke: A marker of irreversible damage?

These authors found that increased cerebral blood flow and volume were seen in the basal ganglia of 4.3% of patients with ischemic strokes with CT perfusion. All patients had underlying MCA occlusions, 30% underwent hemorrhagic transformations, and the hyperperfused areas eventually became infarcted in all. Thus, acute basal ganglia hyperperfusion in patients with stroke may indicate nonviable parenchyma. BACKGROUND AND PURPOSE: CT perfusion scans are often used in acute stroke evaluations. We aimed to assess the outcome of areas of basal ganglia hyperperfusion on CTP in patients with acute ischemic stroke. MATERIALS AND METHODS: We retrospectively reviewed the medical records and brain imaging of 139 patients presenting with acute stroke who underwent CTP for consideration of endovascular recanalization. Hyperperfusion was assessed qualitatively and defined as a matched region of increased cerebral blood flow and cerebral blood volume. CTA was used to locate arterial occlusion. Follow-up imaging was used to determine whether regions of hyperperfusion at baseline became infarcted or developed hemorrhage. Angiographic imaging was assessed to determine the presence or absence of early venous opacification. RESULTS: Six patients (4.3%) demonstrated hyperperfusion in the basal ganglia of the affected side (4 in the lenticular nucleus and 2 in the caudate). In all cases, the area of hyperperfusion ultimately proved to be infarcted. All patients had received intravenous thrombolysis before the CTP. CTA at the time of CTP showed middle or distal M1 occlusion but patency of the proximal M1 and A1 segments. Intracranial hemorrhage was noted in 2 of these 6 patients at follow-up. CONCLUSIONS: Acute basal ganglia hyperperfusion in patients with stroke may indicate nonviable parenchyma and risk of hemorrhagic conversion.

Socioeconomic disparities in the utilization of mechanical thrombectomy for acute ischemic stroke in US hospitals.

BACKGROUND AND PURPOSE: Previous studies have demonstrated that socioeconomic disparities in the treatment of cerebrovascular diseases exist. We studied a large administrative data base to study disparities in the utilization of mechanical thrombectomy for acute ischemic stroke. MATERIALS AND METHODS: With the utilization of the Perspective data base, we studied disparities in mechanical thrombectomy utilization between patient race and insurance status in 1) all patients presenting with acute ischemic stroke and 2) patients presenting with acute ischemic stroke at centers that performed mechanical thrombectomy. We examined utilization rates of mechanical thrombectomy by race/ethnicity (white, black, and Hispanic) and insurance status (Medicare, Medicaid, self-pay, and private). Multivariate logistic regression analysis adjusting for potential confounding variables was performed to study the association between race/insurance status and mechanical thrombectomy utilization. RESULTS: The overall mechanical thrombectomy utilization rate was 0.15% (371/249,336); utilization rate at centers that performed mechanical thrombectomy was 1.0% (371/35,376). In the sample of all patients with acute ischemic stroke, multivariate logistic regression analysis demonstrated that uninsured patients had significantly lower odds of mechanical thrombectomy utilization compared with privately insured patients (OR = 0.52, 95% CI = 0.25–0.95, P = .03), as did Medicare patients (OR = 0.53, 95% CI = 0.41–0.70, P < .0001). Blacks had significantly lower odds of mechanical thrombectomy utilization compared with whites (OR = 0.35, 95% CI = 0.23–0.51, P < .0001). When considering only patients treated at centers performing mechanical thrombectomy, multivariate logistic regression analysis demonstrated that insurance was not associated with significant disparities in mechanical thrombectomy utilization; however, black patients had significantly lower odds of mechanical thrombectomy utilization compared with whites (OR = 0.41, 95% CI = 0.27–0.60, P < .0001). CONCLUSIONS: Significant socioeconomic disparities exist in the utilization of mechanical thrombectomy in the United States.

Safety of intravenous immunoglobulin and plasma exchange in critically ill patients

Abstract Objective: To assess the safety profile of intravenous immunoglobulin (IVIG) and plasma exchange (PLEX) when used to treat critically ill patients. Methods: We performed a retrospective analysis of consecutive patients who received IVIG or PLEX while admitted to our medical intensive care unit (ICU), neuroscience ICU or haematologic/oncologic ICU between 2007 and 2011.Patients who were transferred into an ICU while receiving therapy or who continued therapy after discharge from the ICU were included in the analysis. Results: A total of 118 consecutive patients were included in the study. Fifty-nine patients received IVIG. Twenty of these patients (34%) developed renal failure during the hospitalisation, including 15 (25.4%) in whom renal function worsened during or shortly after IVIG administration and 4 (6.8%) in whom IVIG was considered a possible cause. Transfusion reactions occurred in five patients (8%). Seven patients (12%) did not receive the full intended course of IVIG. Thirty-four patients (58%) who received IVIG died during their hospitalisation. Fifty-nine patients received PLEX. Hypotension requiring an intervention was noted with 39 sessions (8.5%) and led to discontinuation of the session in 11 (2.4%). Other adverse events included line-related infections (n = 4), pneumothorax (n = 4) and electrolyte abnormalities and transfusion reactions (n = 10). Six patients (10%) did not receive full intended treatment course of PLEX. Nineteen patients (32%) treated with PLEX died during their hospitalisation. Discussion: Intravenous immunoglobulin and PLEX are generally well tolerated by critically ill patients. Intravenous immunoglobulin was associated with worsening renal function in one-quarter of patients.