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Open Access Publications from the University of California

Scholarly Works (15 results)

  • Article
  • Peer Reviewed
Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health, Volume 20, Issue 6 (2019)

Introduction: Many dispatch systems send Advanced Life Support (ALS) resources to patientscomplaining of abdominal pain even though the majority of these incidents require only Basic LifeSupport (BLS). With increasing 911-call volume, resource utilization has become more important toensure that ALS resources are available for time-critical emergencies. In 2015, a large, urban firedepartment implemented an internally developed, tiered-dispatch system. Under this system, patientsreporting a chief complaint of abdominal pain received the closest BLS ambulance dispatched aloneemergency if located within three miles of the incident. The objective of this study was to determine thesafety of BLS-only dispatch to abdominal pain by determining the frequency of time-sensitive events.

Methods: This was a retrospective review of electronic health records of one emergency medicalservice provider agency from May 2015-2018. Inclusion criteria were a chief complaint of abdominalpain from a first- or second-party caller, age over 15, and the patient was reported to be alert andbreathing normally. The primary outcome was the prevalence of time-sensitive events, includingcardiopulmonary resuscitation (CPR), defibrillation, or airway management. Secondary outcomeswere hypotension (systolic blood pressure < 90 mmHg); or a prehospital 12 lead-electrocardiogram(ECG) demonstrating ST-elevation myocardial infarction (STEMI) criteria or a wide complex arrhythmia.Descriptive statistics were used.

Results: During the study period, there were 1,220,820 EMS incidents, of which 33,267 (2.72%) metinclusion criteria. The mean age was 49.9 years (range 16-111, standard deviation [SD] 19.6); 14,556patients (56.2%) were female. Time-sensitive events occurred in seven cases (0.021%), mean age was75.3 years (range 30-86, SD18.7); 85.7% were female. Airway management was required in sevencases (0.021%), CPR in six cases (0.018%), and defibrillation in one case (0.003%). Two of the seven(28.6%) cases involved dispatch protocol deviations. Hypotension was present in 240 (0.72%) cases;six (0.018%) cases had 12-lead ECGs meeting STEMI criteria; and no cases demonstrated widecomplex arrhythmia.

Conclusion: Among adult 911 patients with a dispatch chief complaint of abdominal pain, time-sensitiveevents were exceedingly rare. Dispatching a BLS ambulance alone appears to be safe.

    Cover page: Safety of Tiered-Dispatch for 911 Calls for Abdominal PainCreative Commons 'BY' version 4.0 license
    • Article
    • Peer Reviewed
    Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health, Volume 24, Issue 5 (2023)

    Introduction: Persons experiencing homelessness (PEH) use emergency medical services (EMS) at disproportionately high rates relative to housed individuals due to several factors including disparate access to healthcare. Limited access to care is compounded by higher rates of substance use in PEH. Despite growing attention to the opioid epidemic and housing crisis, differences in EMS naloxone administration by housing status has not been systematically examined. Our objective in this study was to describe EMS administration of naloxone by housing status in the City of Los Angeles.

    Methods: This was a 12-month retrospective, cross-sectional analysis of electronic patient care reports (ePCRs) for all 9–1–1 EMS incidents attended by the Los Angeles Fire Department (LAFD), the sole EMS agency for the City of Los Angeles during the study period, January-December 2018. During this time, the City had a population of 3,949,776 with an estimated 31,825 (0.8%) PEH. We included in the study individuals to whom LAFD responders had administered naloxone. Housing status is a mandatory field on ePCRs. The primary study outcome was the incidence of EMS naloxone administration by housing status. We used descriptive statistics and logistic regression models to examine patterns by key covariates.

    Results: There were 345,190 EMS incidents during the study period. Naloxone was administered during 2,428 incidents. Of those incidents 608 (25%) involved PEH, and 1,820 (75%) involved housed individuals. Naloxone administration occurred at a rate of 19 per 1,000 PEH, roughly 44 times the rate of housed individuals. A logistic regression model showed that PEH remained 2.38 times more likely to receive naloxone than their housed counterparts, after adjusting for gender, age, and respiratory depression (odds ratio 2.38, 95% confidence interval 2.15–2.64). The most common impressions recorded by the EMS responders who administered naloxone were the same for both groups: overdose; altered level of consciousness; and cardiac arrest. Persons experiencing homelessness who received naloxone were more likely to be male (82% vs 67%) and younger (41.4 vs 46.2 years) than housed individuals.

    Conclusion: In the City of Los Angeles, PEH are more likely to receive EMS-administered naloxone than their housed peers even after adjusting for other factors. Future research is needed to understand outcomes and improve care pathways for patients confronting homelessness and opioid use.

      Cover page: Does Housing Status Matter in Emergency Medical Services Administration of Naloxone? A Prehospital Cross-sectional StudyCreative Commons 'BY' version 4.0 license
      • Article
      • Peer Reviewed
      UCLA Previously Published Works (2014)

      Rationale

      In acute stroke, the volume of salvageable brain tissue is maximal at onset and declines rapidly with time. Prehospital start of clinical trial interventions would enable delivery of neuroprotective agents, such as magnesium sulfate, to stroke patients in the hyperacute period when they are potentially most effective.

      Aims

      A broad aim of the FAST-MAG study is to develop and validate techniques to perform pivotal trials of neuroprotective therapies for acute stroke in the prehospital setting. In tandem with an accompanying general trial design article, this manuscript provides a detailed overview of several novel prehospital study methods employed in the NIH FAST-MAG Trial.

      Design

      Multicenter, randomized, double-blinded, placebo-controlled, pivotal clinical trial. Special Prehospital Procedures Distinctive prehospital methods deployed in FAST-MAG include: identifying likely stroke patients using the Los Angeles Prehospital Stroke Screen; eliciting explicit informed consent from patients or on scene legally authorized representatives via cellphone discussion with off-scene physicians; paramedic rating of pretreatment stroke severity using the Los Angeles Motor Scale; assigning patients to a study arm using blinded, pre-encounter randomization; facilitating continuity of study infusion from the field to the ED by stocking ambulances with study kits including both field and hospital doses; and electronic fax consent signature documentation by geographically separated subjects and enrolling physicians.

      Discussion

      The suite of prehospital trial methods developed for the FAST-MAG Trial enable enrollment of patients in very early time windows, including the hyperacute, 'golden hour' period immediately after stroke onset.
        Cover page: Protocol
        • Article
        • Peer Reviewed
        UCLA Previously Published Works (2015)

        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.
          Cover page: Routing Ambulances to Designated Centers Increases Access to Stroke Center Care and Enrollment in Prehospital Research
          • Article
          • Peer Reviewed
          UCLA Previously Published Works (2022)
          The objective of this study is to quantify the increase in brain-under-protection time that may be achieved with pre-hospital compared with the post-arrival start of neuroprotective therapy among patients undergoing endovascular thrombectomy. In order to do this, a comparative analysis was performed of two randomized trials of neuroprotective agents: (1) pre-hospital strategy: Field administration of stroke therapy-magnesium (FAST-MAG) Trial; (2) in-hospital strategy: Efficacy and safety of nerinetide for the treatment of acute ischemic stroke (ESCAPE-NA1) Trial. In the FAST-MAG trial, among 1,041 acute ischemic stroke patients, 44 were treated with endovascular reperfusion therapy (ERT), including 32 treated with both intravenous thrombolysis and ERT and 12 treated with ERT alone. In the ESCAPE-NA1 trial, among 1,105 acute ischemic stroke patients, 659 were treated with both intravenous thrombolysis and ERT, and 446 were treated with ERT alone. The start of the neuroprotective agent was sooner after onset with pre-hospital vs. in-hospital start: 45 m (IQR 38-56) vs. 122 m. The neuroprotective agent in FAST-MAG was started 8 min prior to ED arrival compared with 64 min after arrival in ESCAPE-NA1. Projecting modern endovascular workflows to FAST-MAG, the total time of "brain under protection" (neuroprotective agent start to reperfusion) was greater with pre-hospital than in-hospital start: 94 m (IQR 90-98) vs. 22 m. Initiating a neuroprotective agent in the pre-hospital setting enables a faster treatment start, yielding 72 min additional brain protection time for patients with acute ischemic stroke. These findings provide support for the increased performance of ambulance-based, pre-hospital treatment trials in the development of neuroprotective stroke therapies.
            Cover page: Quantifying the amount of greater brain ischemia protection time with pre-hospital vs. in-hospital neuroprotective agent start
            • Article
            • Peer Reviewed
            UCLA Previously Published Works (2020)
            Background and Purpose- The prehospital setting is a promising site for therapeutic intervention in stroke, but current stroke screening tools do not account for the evolution of neurological symptoms in this early period. We developed and validated the Paramedic Global Impression of Change (PGIC) Scale in a large, prospective, randomized trial. Methods- In the prehospital FAST-MAG (Field Administration of Stroke Therapy-Magnesium) randomized trial conducted from 2005 to 2013, EMS providers were asked to complete the PGIC Scale (5-point Likert scale values: 1-much improved, 2-mildly improved, 3-unchanged, 4-mildly worsened, 5-much worsened) for neurological symptom change during transport for consecutive patients transported by ambulance within 2 hours of onset. We analyzed PGIC concurrent validity (compared with change in Glasgow Coma Scale, Los Angeles Motor Scale), convergent validity (compared with National Institutes of Health Stroke Scale severity measure performed in the emergency department), and predictive validity (of neurological deterioration after hospital arrival and of final 90-day functional outcome). We used PGIC to characterize differential prehospital course among stroke subtypes. Results- Paramedics completed the PGIC in 1691 of 1700 subjects (99.5%), among whom 635 (37.5%) had neurological deficit evolution (32% improvement, 5.5% worsening) during a median prehospital care period of 33 (IQR, 27-39) minutes. Improvement was associated with diagnosis of cerebral ischemia rather than intracranial hemorrhage, milder stroke deficits on emergency department arrival, and more frequent nondisabled and independent 3-month outcomes. Conversely, worsening on the PGIC was associated with intracranial hemorrhage, more severe neurological deficits on emergency department arrival, more frequent treatment with thrombolytic therapy, and poor disability outcome at 3 months. Conclusions- The PGIC scale is a simple, validated measure of prehospital patient course that has the potential to provide information useful to emergency department decision-making. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT00059332.
              Cover page: Paramedic Global Impression of Change During Prehospital Evaluation and Transport for Acute Stroke.
              • Article
              • Peer Reviewed
              UCLA Previously Published Works (2019)
              Background and Purpose: Primary stroke center (PSC) certification is associated with improvements in stroke care and outcome. However, these improvements may reflect a higher baseline level of care delivery in hospitals eventually achieving certification. This study examines whether advancements in acute stroke care at PSCs are due to certification or factors intrinsic to the hospital. Methods: Data was obtained from the Field Administration of Stroke Therapy-Magnesium (FAST-MAG) trial with participation of 40 Emergency Medical System agencies, 315 ambulances, and 60 acute receiving hospitals in Los Angeles and Orange Counties. Subjects were transported to one of three types of destinations: PSC certified hospitals (PSCs), hospitals that were not PSCs at time of enrollment but would later become certified (pre-PSCs), and hospitals that would never be certified (non-PSCs). Metrics of acute stroke care quality included time arrival to imaging, use of intravenous tPA, and arrival to treatment. Results: Of 1,700 cases, 856(50%) were at certified PSCs, 529(31%) were at pre-PSCs, and 315 (19%) were at non-PSCs. Mean (SD) was 33min (±76.1) at PSCs, 47(±86.6) at pre-PSCs, and 49(±71.7) at non-PSCs. Of 1,223 cerebral ischemia cases, rate of tPA utilization was 43% at PSCs, 27% at pre-PSCs, and 28% at non-PSCs. Mean ED arrival to thrombolysis was 71(±32.7) at PSC, 98(±37.6) at pre-PSC, and 95(±45.0) at non-PSCs. PSCs had improved time to imaging (p = 0.014), percent tPA use (p < 0.001), and time to treatment (p = 0.003). Conclusions: Stroke care at hospitals prior to PSC certification is equivalent to care at non-PSCs. Clinical Trial Registration: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.
                Cover page: Quality of Acute Stroke Care at Primary Stroke Centers Before and After Certification in Comparison to Never-Certified Hospitals.
                • Article
                • Peer Reviewed
                UCLA Previously Published Works (2014)

                Rationale

                Prehospital initiation by paramedics may enable delivery of neuroprotective therapies to stroke patients in the hyperacute period when they are most effective in preclinical studies. Magnesium is neuroprotective in experimental stroke models and has been shown to be safe with signals of potential efficacy when started early after onset of human cerebral ischemia.

                Aims

                (a) To demonstrate that paramedic initiation of the neuroprotective agent magnesium sulfate in the field is an efficacious and safe treatment for acute stroke; (b) To demonstrate that field enrollment of acute stroke patients is a practical and feasible strategy for phase 3 stroke trials, permitting enrollment of greater numbers of patients in hyperacute time windows.

                Design

                Multicenter, randomized, double-blinded, placebo-controlled, pivotal clinical trial.

                Study procedures

                The study is enrolling 1700 patients (850 in each arm) with likely acute stroke, including both cerebral infarction and intracerebral hemorrhage patients. Inclusion criteria are: (a) likely stroke as identified by the modified Los Angeles Prehospital Stroke Screen (mLAPSS), (b) age 40-95, (c) symptom onset within 2 h of treatment initiation, and (d) deficit present ≥15 min. Paramedics administer a loading dose of magnesium sulfate (Mg) or matched placebo in the field, 4 grams over 15 min. In the Emergency Department, a maintenance infusion follows, 16 grams Mg or matched placebo over 24 h.

                Outcomes

                The primary endpoint is the modified Rankin Scale measure of global disability, assessed using the Rankin Focused Assessment, 90 days after treatment. Secondary efficacy endpoints include the NIHSS (neurologic deficit), Barthel Index (activities of daily living), and the Stroke Impact Scale (quality of life).
                  Cover page: Protocol
                  • Article
                  • Peer Reviewed
                  UCLA Previously Published Works (2019)

                  Background and purpose

                  Subject retention into clinical trials is vital, and prehospital enrollment may be associated with higher rates of subject withdrawal than more traditional methods of enrollment. We describe rates of subject retention in a prehospital trial of acute stroke therapy.

                  Methods

                  All subjects were enrolled into the NIH Field Administration of Stroke Therapy-Magnesium (FAST-MAG) phase 3 clinical trial. Paramedics screened eligible subjects and contacted the physician-investigator using a dedicated in-ambulance cellular phone. Physician-investigators obtained explicit informed consent from the subject or on-scene legally authorized representative (LAR) who reviewed and signed a consent form. Exception from informed consent (EFIC) was utilized in later stages of the study.

                  Results

                  There were 1,700 subjects enrolled; 1,017 provided consent (60%), 662 were enrolled via LAR (39%), and 21 were enrolled via EFIC (1%). Of the 1,700 patients, 1,413 (83%) completed the 90-day visit, 265 (16%) died prior to the 90-day visit, and 22 (1.3%) withdrew from the study before completion. There were no differences in rates of withdrawal by method of study enrolment, i.e., self-consent (n = 14), 1.4%; LAR (n = 8), 1.2%; EFIC (n = 0) 0%.

                  Conclusion

                  There was a high rate of retention when subjects were enrolled into prehospital stroke research using a phone-based method to obtain explicit consent.
                    Cover page: Subject Retention in Prehospital Stroke Research Using a Telephone-Based Physician-Investigator Driven Enrollment Method
                    • Article
                    • Peer Reviewed
                    UCLA Previously Published Works (2020)
                    BACKGROUND: Cardiac adverse events are common among patients presenting with acute stroke and contribute to overall morbidity and mortality. Prophylactic measures for the reduction of cardiac adverse events in hospitalized stroke patients have not been well understood. We sought to investigate the effect of early initiation of high-dose intravenous magnesium sulfate on cardiac adverse events in stroke patients. METHODS: This is a secondary analysis of the prehospital Field Administration of Stroke Therapy-Magnesium (FAST-MAG) randomized phase-3 clinical trial, conducted from 2005-2013. Consecutive patients with suspected acute stroke and a serum magnesium level within 72 hours of enrollment were selected. Twenty grams of magnesium sulfate or placebo was administered in the ambulance starting with a 15-minute loading dose intravenous infusion followed by a 24-hour maintenance infusion in the hospital. RESULTS: Among 1126 patients included in the analysis of this study, 809 (71.8%) patients had ischemic stroke, 277 (24.6%) had hemorrhagic stroke, and 39 (3.5%) with stroke mimics. The mean age was 69.5 (SD13.4) and 42% were female. 565 (50.2%) received magnesium treatment, and 561 (49.8%) received placebo. 254 (22.6%) patients achieved the target, and 872 (77.4%) did not achieve the target, regardless of their treatment group. Among 1126 patients, 159 (14.1%) had at least one CAE. Treatment with magnesium was not associated with fewer cardiac adverse events. A multivariate binary logistic regression for predictors of CAEs showed a positive association of older age and frequency of CAEs (R = 1.04, 95% CI 1.03-1.06, p < 0.0001). Measures of early and 90-day outcomes did not differ significantly between the magnesium and placebo groups among patients who had CAEs. CONCLUSION: Treatment of acute stroke patients with magnesium did not result in a reduction in the number or severity of cardiac serious adverse events.
                      Cover page: The Effect of Early Treatment with Intravenous Magnesium Sulfate on the Incidence of Cardiac Comorbidities in Hospitalized Stroke Patients.
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