Franklin D Pratt

Prehospital use of magnesium sulfate as neuroprotection in acute stroke.

BACKGROUND Magnesium sulfate is neuroprotective in preclinical models of stroke and has shown signals of potential efficacy with an acceptable safety profile when delivered early after stroke onset in humans. Delayed initiation of neuroprotective agents has hindered earlier phase 3 trials of neuroprotective agents. METHODS We randomly assigned patients with suspected stroke to receive either intravenous magnesium sulfate or placebo, beginning within 2 hours after symptom onset. A loading dose was initiated by paramedics before the patient arrived at the hospital, and a 24-hour maintenance infusion was started on the patients arrival at the hospital. The primary outcome was the degree of disability at 90 days, as measured by scores on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability). RESULTS Among the 1700 enrolled patients (857 in the magnesium group and 843 in the placebo group), the mean (±SD) age was 69±13 years, 42.6% were women, and the mean pretreatment score on the Los Angeles Motor Scale of stroke severity (range, 0 to 10, with higher scores indicating greater motor deficits) was 3.7±1.3. The final diagnosis of the qualifying event was cerebral ischemia in 73.3% of patients, intracranial hemorrhage in 22.8%, and a stroke-mimicking condition in 3.9%. The median interval between the time the patient was last known to be free of stroke symptoms and the start of the study-drug infusion was 45 minutes (interquartile range, 35 to 62), and 74.3% of patients received the study-drug infusion within the first hour after symptom onset. There was no significant shift in the distribution of 90-day disability outcomes on the global modified Rankin scale between patients in the magnesium group and those in the placebo group (P=0.28 by the Cochran-Mantel-Haenszel test); mean scores at 90 days did not differ between the magnesium group and the placebo group (2.7 in each group, P=1.00). No significant between-group differences were noted with respect to mortality (15.4% in the magnesium group and 15.5% in the placebo group, P=0.95) or all serious adverse events. CONCLUSIONS Prehospital initiation of magnesium sulfate therapy was safe and allowed the start of therapy within 2 hours after the onset of stroke symptoms, but it did not improve disability outcomes at 90 days. (Funded by the National Institute of Neurological Disorders and Stroke; FAST-MAG ClinicalTrials.gov number, NCT00059332.).

Prospective study of manikin-only versus manikin and human subject endotracheal intubation training of paramedics

STUDY OBJECTIVES To determine the effect of manikin-only training on field success of endotracheal intubation by paramedics. DESIGN Prospective evaluation of individual field endotracheal intubation success rates for paramedics after they participated in a manikin-only or a manikin-plus-cadaver training program. TYPES OF PARTICIPANTS Paramedics responding to emergency calls involving adult medical or trauma victims. INTERVENTIONS All participants were trained using a controlled manikin training program; then, half were randomly selected for additional instruction using fresh human cadavers. MEASUREMENTS AND MAIN RESULTS Individuals trained using only the manikin program had mean +/- SD individual success rates of 82 +/- 32%, and individuals who received additional cadaver training had mean individual success rates of 83 +/- 31%. Overall success rates for the two groups were 86% for the manikin-only group and 85% for the manikin-plus-cadaver-trained group. The sample size was not adequate to allow rejection of the null hypothesis. CONCLUSION Paramedics trained in endotracheal intubation using a systematic manikin-only teaching program can attain acceptable individual success rates in the actual field setting.

Impact of Paramedic Transport with Prehospital 12-Lead Electrocardiography on Door-to-Balloon Times for Patients with ST-Segment Elevation Myocardial Infarction

Objective. To determine the impact of prehospital 12-lead electrocardiograms (ECGs) on door-to-balloon times for ST-segment elevation myocardial infarction (STEMI) patients prior to the establishment of formally designated STEMI receiving centers. Methods. This was a retrospective study comparing door-to-balloon times for acute STEMI patients transported by paramedics using prehospital 12-lead ECGs with those who arrived via self-transport at four Los Angeles area EDs that performed emergency percutaneous coronary intervention (PCI). Paramedics calling in from the field verbally notified receiving hospitals of a “STEMI patient.” Activation of the hospitals PCI team was at the discretion of the receiving emergency physician. During the study period, there were no formal diversion criteria for STEMI patients. The main outcome measure was door-to-balloon time. Results. During the study period, 234 patients met inclusion criteria, of whom 168 (72%) were male. The mean age was 62 years. There was no statistically significant difference in the age, gender, or ethnicity of the two groups. Median door-to-balloon times were 95 minutes and108 minutes in the EMS andself-transport groups, respectively (p < 0.05; 95% confidence interval 3.5–16.4). Conclusion. Paramedic transport of STEMI patients with prehospital 12-lead ECG acquisition was associated with shorter door-to-balloon times than the times for patients who self-transported to PCI-capable EDs

Routing Ambulances to Designated Centers Increases Access to Stroke Center Care and Enrollment in Prehospital Research

Background and Purpose— Emergency medical services routing of patients with acute stroke to designated centers may increase the proportion of patients receiving care at facilities meeting national standards and augment recruitment for prehospital stroke research. Methods— We analyzed consecutive patients enrolled within 2 hours of symptom onset in a prehospital stroke trial, before and after regional Los Angeles County Emergency Medical Services implementation of preferentially routing patients with acute stroke to approved stroke centers (ASCs). From January 2005 to mid-November 2009, patients were transported to the nearest emergency department, whereas from mid-November 2009 to December 2012, patients were preferentially transported to first 9, and eventually 29, ASCs. Results— There were 863 subjects enrolled before and 764 after emergency medical service preferential routing, with implementation leading to an increase in the proportion cared for at an ASC from 10% to 91% (P<0.0001), with a slight decrease in paramedic on-scene to emergency department arrival time (34.5 [SD, 9.1] minutes versus 33.5 [SD, 10.3] minutes; P=0.045). The effects of routing were immediate and included an increase in proportion of receiving ASC care (from 17% to 88%; P<0.001) and a greater number of enrollments (18.6% increase) when comparing 12 months before and after regional stroke system implementation. Conclusions— The establishment of a regionalized emergency medical services system of acute stroke care dramatically increased the proportion of patients with acute stroke cared for at ASCs, from 1 in 10 to >9 in 10, with no clinically significant increase in prehospital care times and enhanced recruitment of patients into a prehospital treatment trial. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.

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.

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.