Latisha Sharma

Field Validation of the Los Angeles Motor Scale as a Tool for Paramedic Assessment of Stroke Severity

Background and Purpose— The Los Angeles Motor Scale (LAMS) is a 3-item, 0- to 10-point motor stroke-deficit scale developed for prehospital use. We assessed the convergent, divergent, and predictive validity of the LAMS when performed by paramedics in the field at multiple sites in a large and diverse geographic region. Methods— We analyzed early assessment and outcome data prospectively gathered in the FAST-MAG trial (Field Administration of Stroke Therapy–Magnesium phase 3) among patients with acute cerebrovascular disease (cerebral ischemia and intracranial hemorrhage) within 2 hours of onset, transported by 315 ambulances to 60 receiving hospitals. Results— Among 1632 acute cerebrovascular disease patients (age 70±13 years, male 57.5%), time from onset to prehospital LAMS was median 30 minutes (interquartile range 20–50), onset to early postarrival (EPA) LAMS was 145 minutes (interquartile range 119–180), and onset to EPA National Institutes of Health Stroke Scale was 150 minutes (interquartile range 120–180). Between the prehospital and EPA assessments, LAMS scores were stable in 40.5%, improved in 37.6%, and worsened in 21.9%. In tests of convergent validity, against the EPA National Institutes of Health Stroke Scale, correlations were r=0.49 for the prehospital LAMS and r=0.89 for the EPA LAMS. Prehospital LAMS scores did diverge from the prehospital Glasgow Coma Scale, r=−0.22. Predictive accuracy (adjusted C statistics) for nondisabled 3-month outcome was as follows: prehospital LAMS, 0.76 (95% confidence interval 0.74–0.78); EPA LAMS, 0.85 (95% confidence interval 0.83–0.87); and EPA National Institutes of Health Stroke Scale, 0.87 (95% confidence interval 0.85–0.88). Conclusions— In this multicenter, prospective, prehospital study, the LAMS showed good to excellent convergent, divergent, and predictive validity, further establishing it as a validated instrument to characterize stroke severity in the field.

Visual Aids for Patient, Family, and Physician Decision Making About Endovascular Thrombectomy for Acute Ischemic Stroke

Background and Purpose— Rapid decision making optimizes outcomes from endovascular thrombectomy for acute cerebral ischemia. Visual displays facilitate swift review of potential outcomes and can accelerate decision processes. Methods— From patient-level, pooled randomized trial data, 100 person-icon arrays (Kuiper–Marshall personographs) were generated showing beneficial and adverse effects of endovascular thrombectomy for patients with acute cerebral ischemia and large vessel occlusion using (1) automated (algorithmic) and (2) expert-guided joint outcome table specification. Results— For the full 7-category modified Rankin Scale, thrombectomy added to IV tPA (intravenous tissue-type plasminogen activator) alone had number needed to treat to benefit 2.9 (95% confidence interval, 2.6–3.3) and number needed to harm 68.9 (95% confidence interval, 40–250); thrombectomy for patients ineligible for IV tPA had number needed to treat to benefit 2.3 (95% confidence interval, 2.1–2.5) and number needed to harm 100 (95% confidence interval, 62.5–250). Visual displays of treatment effects on 100 patients showed: with thrombectomy added to IV tPA alone, 34 patients have better disability outcome, including 14 more normal or near normal (modified Rankin Scale, 0–1); with thrombectomy for patients ineligible for IV tPA, 44 patients have a better disability outcome, including 16 more normal or nearly normal. Displays also showed that harm (increased modified Rankin Scale final disability) occurred in 1 of 100 patients in both populations, mediated by increased new territory infarcts. The person-icon figures integrated these outcomes, and early side-effects, in a single display. Conclusions— Visual decision aids are now available to rapidly educate healthcare providers, patients, and families about benefits and risks of endovascular thrombectomy, both when added to IV tPA in tPA-eligible patients and as the sole reperfusion treatment in tPA-ineligible patients.

Los Angeles Motor Scale to Identify Large Vessel Occlusion: Prehospital Validation and Comparison With Other Screens

Background and Purpose— Prehospital scales have been developed to identify patients with acute cerebral ischemia (ACI) because of large vessel occlusion (LVO) for direct routing to Comprehensive Stroke Centers (CSCs), but few have been validated in the prehospital setting, and their impact on routing of patients with intracranial hemorrhage has not been delineated. The purpose of this study was to validate the Los Angeles Motor Scale (LAMS) for LVO and CSC-appropriate (LVO ACI and intracranial hemorrhage patients) recognition and compare the LAMS to other scales. Methods— The performance of the LAMS, administered prehospital by paramedics to consecutive ambulance trial patients, was assessed in identifying (1) LVOs among all patients with ACI and (2) CSC-appropriate patients among all suspected strokes. Additionally, the LAMS administered postarrival was compared concurrently with 6 other scales proposed for paramedic use and the full National Institutes of Health Stroke Scale. Results— Among 94 patients, age was 70 (±13) and 49% female. Final diagnoses were ACI in 76% (because of LVO in 48% and non-LVO in 28%), intracranial hemorrhage in 19%, and neurovascular mimic in 5%. The LAMS administered by paramedics in the field performed moderately well in identifying LVO among patients with ACI (C statistic, 0.79; accuracy, 0.72) and CSC-appropriate among all suspected stroke transports (C statistic, 0.80; accuracy, 0.72). When concurrently performed in the emergency department postarrival, the LAMS showed comparable or better accuracy versus the 7 comparator scales, for LVO among ACI (accuracies LAMS, 0.70; other scales, 0.62–0.68) and CSC-appropriate (accuracies LAMS, 0.73; other scales, 0.56–0.73). Conclusions— The LAMS performed in the field by paramedics identifies LVO and CSC-appropriate patients with good accuracy. The LAMS performs comparably or better than more extended prehospital scales and the full National Institutes of Health Stroke Scale.

Early Blood-Brain Barrier Disruption after Mechanical Thrombectomy in Acute Ischemic Stroke: Early BBB Disruption after Mechanical Thrombectomy in Stroke

The impact of blood‐brain barrier (BBB) disruption can be detected by intraparenchymal hyperdense lesion on the computed tomography (CT) scan after endovascular stroke therapy. The purpose of this study was to determine whether early BBB disruption predicts intracranial hemorrhage and poor outcome in patients with acute ischemic stroke treated with mechanical thrombectomy.

Paramedic Initiation of Neuroprotective Agent Infusions: Successful Achievement of Target Blood Levels and Attained Level Effect on Clinical Outcomes in the FAST-MAG Pivotal Trial (Field Administration of Stroke Therapy – Magnesium)

Background and Purpose— Paramedic use of fixed-size lumen, gravity-controlled tubing to initiate intravenous infusions in the field may allow rapid start of neuroprotective therapy for acute stroke. In a large, multicenter trial, we evaluated its efficacy in attaining target serum levels of candidate neuroprotective agent magnesium sulfate and the relation of achieved magnesium levels to outcome. Methods— The FAST-MAG phase 3 trial (Field Administration of Stroke Therapy – Magnesium) randomized 1700 patients within 2 hours of onset to paramedic-initiated, a 15-minute loading intravenous infusion of magnesium or placebo followed by a 24-hour maintenance dose. The drug delivery strategy included fixed-size lumen, gravity-controlled tubing for field drug administration, and a shrink-wrapped ambulance kit containing both the randomized field loading and hospital maintenance doses for seamless continuation. Results— Among patient randomized to active treatment, magnesium levels in the first 72 hours were assessed 987 times in 572 patients. Mean patient age was 70 years (SD±14 years), and 45% were women. During the 24-hour period of active infusion, mean achieved serum level was 3.91 (±0.8), consistent with trial target. Mg levels were increased by older age, female sex, lower weight, height, body mass index, and estimated glomerular filtration rate, and higher blood urea nitrogen, hemoglobin, and higher hematocrit. Adjusted odds for clinical outcomes did not differ by achieved Mg level, including disability at 90 days, symptomatic hemorrhage, or death. Conclusions— Paramedic infusion initiation using gravity-controlled tubing permits rapid achievement of target serum levels of potential neuroprotective agents. The absence of association of clinical outcomes with achieved magnesium levels provides further evidence that magnesium is not biologically neuroprotective in acute stroke.

ASPECTS-based reperfusion status on arterial spin labeling is associated with clinical outcome in acute ischemic stroke patients:

The purpose of this study was to develop and evaluate a scoring system for assessing reperfusion status based on arterial spin labeled (ASL) perfusion MRI in acute ischemic stroke (AIS) patients receiving thrombolysis and/or endovascular treatment. Pseudo-continuous ASL with background suppressed 3D GRASE was acquired along with DWI in 90 patients within 24 h post-treatment. An automatic reperfusion scoring system (auto-RPS) was devised based on the Alberta Stroke Program Early CT Score (ASPECTS) template, and compared with manual RPS and DWI-ASPECTS. TICI (thrombolysis in cerebral infarction) scores were graded in 48 patients who received endovascular treatment. Favorable outcomes were defined by a modified Rankin Scale score of 0–2 at three months. Auto-RPS was positively correlated with DWI-ASPECTS (ρ = 0.6, P < 0.001) and was on average 1 point lower than DWI-ASPECTS (P < 0.001). The area under the receiver operating characteristic curve for discriminating poor functional outcome (n = 90) was 0.75 (95% CI, 0.64–0.86) for manual RPS, 0.85 (95% CI, 0.76–0.94) for auto-RPS, and 0.81 (95% CI, 0.71–0.90) for DWI-ASPECTS. Multiple logistic regression analysis in the TICI-graded patients (n = 48) showed that auto-RPS is highly associated with functional outcome (OR = 25.2, 95% CI 4.02–496, P < 0.01). Post treatment auto-RPS within 24 h provides a useful tool to predict functional outcome in AIS patients.

The Frequency of Substantial Salvageable Penumbra in Thrombectomy-ineligible Patients with Acute Stroke: Frequency of Nonperfusable Penumbra

Endovascular therapy (ET) has become the standard of care for selected patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). However, many LVO or medium vessel occlusion (MVO) patients are ineligible for ET, including some who harbor salvageable tissues. To develop complementary therapies for these patients, it is important to delineate their prevalence, clinical features, and outcomes.

A Dedicated Spanish Language Line Increases Enrollment of Hispanics Into Prehospital Clinical Research

Background and Purpose— Novel methods are needed to reduce the disparity of Hispanic enrollment in stroke clinical trials. Prehospital enrollment using a dedicated Spanish language line may help overcome this bias. Methods— Subjects or legally authorized representatives provided information on race and ethnicity for all cases enrolled in the FAST-MAG clinical trial (Field Administration of Stroke Therapy-Magnesium), a prehospital phase 3 randomized study of intravenous magnesium for neuroprotection. One of 2 in-ambulance cell phones (in English or Spanish) was used to obtain informed content in the field. We describe the yield and characteristics of subjects enrolled via Spanish line. Results— There were 1700 subjects enrolled from 2005 to 2012, of which 402 (24%) identified as Hispanic ethnicity. Study racial makeup was 1325 (78%) white, 219 (13%) black, and 139 (8%) Asian. The dedicated Spanish line was used for 195 (12%) enrollments. Spanish-line enrollments were younger (65 versus 70 years old; P<0.001), more likely to identify as Hispanic (98% versus 14%; P<0.001), and more likely to present with intracerebral hemorrhage (36% versus 21%; P<0.001). Conclusions— The use of a dedicated Spanish language enrollment line allowed for greater enrollment of Hispanics, a population with significantly different baseline characteristics. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.