The Utility of Prehospital ECG Transmission in a Large EMS System.

BACKGROUND: Prehospital identification of STEMI and activation of the catheterization lab can improve door-to-balloon (D2B) times but may lead to decreased specificity and unnecessary resource utilization. The purpose of this study was to examine the effect of electrocardiogram (ECG) transmission on false-positive (FP) cath lab activations and time to reperfusion. METHODS: This is a retrospective cohort from a registry in a large metropolitan area with regionalized cardiac care and emergency medical services (EMS) with ECG transmission capabilities. Thirty-four designated STEMI receiving centers (SRC) contribute to this registry, from which patients with a prehospital ECG software interpretation of myocardial infarction (MI) indicated by ****Acute MI****, or manufacturer equivalent, were identified between April 2011 and September 2013. Frequency of FP field activations (defined as not resulting in emergent percutaneous coronary intervention [PCI] or referral for CABG during hospital admission) for patients with ECG transmission received by the SRC was compared to a reference group without successful ECG transmission. FP field activations were compared to the baseline frequency of FP ED activations. We hypothesized that successful transmission would reduce FP field activation to ED activation levels. Door-to-balloon and first medical contact-to-balloon (FMC2B) times were compared. The protocol for field cath lab activation varied by institution. RESULTS: There were 7,768 patients presenting with a prehospital ECG indicating MI. The ECG was received by the SRC for 2,156 patients (28%). Regardless of transmission, the cath lab was activated 77% of the time; this activation occurred from the field in 73% and 74% of the activations in the transmission and reference group, respectively. The overall proportion of FP activation was 57%. Among field activations, successful ECG transmission reduced the FP activation rate compared to without ECG transmission, 55% vs. 61% (RD = -6%, 95%CI -9, -3%). This led to an overall system reduction in FP activations of 5% (95%CI 2, 8%). ECG transmission had no effect on D2B and FMC2B time. CONCLUSION: Prehospital ECG transmission is associated with a small reduction in false-positive field activations for STEMI and had no effect on time to reperfusion in this cohort.

Effect of prehospital cardiac catheterization lab activation on door-to-balloon time, mortality, and false-positive activation.

BACKGROUND: Reperfusion of ST elevation myocardial infarction (STEMI) is most effective when performed early. Notification of the cardiac catheterization laboratory (cath lab) prior to hospital arrival based on paramedic-performed ECGs has been proposed as a strategy to decrease time to reperfusion and mortality. The purpose of this study was to compare the effects of cath lab activation prior to patient arrival versus activation after arrival at the emergency department (ED). METHODS: We performed a retrospective cohort study (n = 1933 cases) using Los Angeles County STEMI database from May 1, 2008 through August 31, 2009. The database includes patients arriving at a STEMI Receiving Center (SRC) by ambulance who were diagnosed with STEMI either before or after hospital arrival. We compared the cohort of patients with prehospital cath lab activation to those activated from the ED within 5 minutes of first ED ECG. Outcomes measured were mortality, door-to-balloon time, percent door-to-balloon time <90 min, and percentage of false-positive activations. RESULTS: Prehospital cath lab activations had mean door-to-balloon times 14 minutes shorter (95% CI 11-17), in-hospital mortality 1.5% higher (95% CI -1.0-5.2), and false-positive activation 7.8%, (95% CI 2.7-13.3) higher than ED activation. For prehospital activation, 93% (95% CI 91-94%) met a door-to-balloon target of 90 minutes versus 85% (95% CI 80-88%) for ED activations. CONCLUSION: Prehospital cath lab activation based on the prehospital ECG was associated with decreased door-to-balloon times but did not affect hospital mortality. False-positive activation was common and occurred more often with prehospital STEMI diagnosis.

Risk factors for apnea in children presenting with out-of-hospital seizure.

OBJECTIVE: This study aimed to quantify risk factors for apnea in children 0 to 5 years of age with out-of-hospital seizure. METHODS: This is a retrospective study of pediatric patients with seizure transported by paramedics to the pediatric emergency department (PED) of a tertiary center from July 2008 to June 2009. Patients with traumatic injury and those with another diagnosis after PED evaluation were excluded. We evaluated the effect of field diazepam and other potential risk factors on the occurrence of apnea, defined as the need for airway management, that is, bag-mask ventilation by paramedics or bag-mask ventilation or intubation by PED staff within 30 minutes of arrival. RESULTS: There were 336 pediatric patients meeting inclusion criteria. The median age was 1.9 years (interquartile range,1.3-3.0 years); 193 patients (57%) were male. Fifty-four patients (16%) were treated with diazepam before PED arrival. There were 28 apneic events (8.3%). The adjusted relative risk for apnea given diazepam in the field by any route was 10.2 (95% confidence interval, 3.9-21.8; P < 0.0001), adjusted for age and seizure on arrival. Persistent seizure on PED arrival was also highly associated with apnea, with an adjusted relative risk of 15.8 (95% confidence interval, 6.5-28.9; P < 0.0001). CONCLUSIONS: Field treatment with diazepam and seizing at the time of PED arrival are associated with the occurrence of apnea in children 0 to 5 years of age with out-of-hospital seizure. Larger studies are needed to determine what other factors may contribute to this risk.

Medical events during the 2009 Los Angeles County Station Fire: lessons for wildfire EMS planning.

BACKGROUND: Little is known about the types of injuries and medical problems encountered by fire department personnel during suppression of large campaign-type wildland fires. Such information could help to plan for response to medical incidents during future wildfires. OBJECTIVE: To describe the injuries and medical problems experienced by firefighters during the 2009 Los Angeles County Station Fire. METHODS: This was a retrospective analysis of case records of patients treated during the Los Angeles County Station Fire. Data were abstracted from two sources: the incident command medical tracking sheet and prehospital patient care reports (PCRs). RESULTS: The sample included 183 patient contacts, of which PCRs were available for 65. For the remaining 118 patients, data were abstracted from the incident command medical tracking sheet. The most common chief complaint was extremity injury, accounting for 44 patient contacts (24% of all patients), with smoke inhalation second, at 32 patient contacts (17%). Of the 65 patients with PCRs, 31 (52%) were treated with oxygen, 26 (40%) had intravenous (IV) lines started, and 15 (23%) received an IV fluid bolus. Half of the patients were transported to an emergency department (ED); the remainder were treated on scene or self-transported to a non-acute care facility. CONCLUSIONS: Most firefighter injuries and illnesses encountered during the Los Angeles Station Fire were minor. The prevalence of injuries observed should be taken into consideration in creation of protocols and mandatory equipment lists for fireline paramedics. Furthermore, advanced training for paramedics in the diagnosis and treatment of minor medical conditions may be useful.

Ondansetron is safe and effective for prehospital treatment of nausea and vomiting by paramedics.

UNLABELLED: OBJCTIVE: The objectives were to evaluate the safety and efficacy of ondansetron in the out-of-hospital treatment of undifferentiated nausea or vomiting. METHODS: Patients with severe nausea or intractable vomiting who were transported by paramedic-staffed ambulances in eight California counties were treated with intravenous (IV), intramuscular (IM), or oral dissolving tablet (ODT) administration of ondansetron. Data were collected prospectively for a six-month period using an online database. Prospectively defined outcome measures were 1) efficacy as measured by a quantitative visual analog nausea scale and 2) incidence of adverse effects. There were no control or placebo groups. RESULTS: Data was collected for 2072 patients, but one patient did not receive the medication. Therefore, Ondansetron was administered to 2,071 patients (3.7% of transported patients). Most patients were adult, with only 66 patients less than 18 years old. Of the 2,071 patients, 1,320 (64%) received IV administration, 77 (4%) received IM administration, and 674 (33%) received ODT administration of ondansetron. Intravenous administration resulted in the largest improvements in nausea scores (mean 4.4; 95% confidence interval [CI] 4.2, 4.5), followed by IM (mean 3.6; 95% CI 3.0, 4.3) and ODT (mean 3.3; 95% CI 3.1, 3.5). Overall, the mean decrease in nausea score was 4.0 (95% CI 3.9, 4.1; p < 0.001) on a 10-point scale. After medication administration, four patients had mild hypotension, one had hypertension, two had itching or rash, and one had a brief episode of supraventricular tachycardia that resolved spontaneously. CONCLUSIONS: Ondansetron is safe and effective for out-of-hospital treatment of nausea and vomiting when administered by paramedics via the IV, IM, or oral route. When available to paramedics, ondansetron is used frequently.

At-risk populations and the critically ill rely disproportionately on ambulance transport to emergency departments.

STUDY OBJECTIVE: Emergency department (ED) crowding increases ambulance diversion. Ambulance diversion disproportionately affects individuals who rely on ambulance transport. The purpose of this study is to determine which populations rely most on ambulance transport. METHODS: We queried the National Hospital Ambulatory Medical Care Survey database for 1997 to 2000 and 2003 to 2005 for patients who arrived by ambulance or personal transport. We performed bivariate analysis to assess the extent to which all patients and a subset of critically ill patients use ambulance transport relative to self-transport. RESULTS: In our sample, 30,455 (15%; 95% confidence interval [CI] 15% to 16%) patients arrived by ambulance and 162,091 (85%; 95% CI 84% to 85%) arrived by walk-in/self-transport. Overall, patients with Medicare insurance were more likely to rely on ambulance transport, at 34% (95% CI 33% to 35%), than the privately insured, at 11% (95% CI 10% to 11%). Among the critically ill, privately insured patients were less likely to rely on ambulance transport, at 47% (95% CI 42% to 52%), than those with Medicare insurance (61%; 95% CI 58% to 65%), the publicly insured (60%; 95% CI 52% to 67%), or the uninsured (57%; 95% CI 49% to 64%). Among the critically ill, patients aged 15 to 24 years and those older than 74 years were most likely to rely on ambulance transport, at 63% (95% CI 53% to 72%) and 67% (95% CI 62% to 71%), respectively. Fifty-seven percent (95% CI 54% to 59%) of the critically ill used ambulance versus 15% (95% CI 14% to 15%) of noncritical patients. CONCLUSION: Patients with Medicare insurance or public insurance, the uninsured, the elderly, and the critically ill disproportionately rely on ambulance transport to the ED. Ambulance diversion may disproportionately affect these populations.

ABSCESS: applied bedside sonography for convenient evaluation of superficial soft tissue infections.

OBJECTIVES: Soft tissue infections are a common presenting complaint in the emergency department (ED). The authors sought to determine the utility of ED bedside ultrasonography (US) in detecting subcutaneous abscesses. METHODS: Between August 2003 and November 2004, a prospective, convenience sample of adult patients with a chief complaint suggestive of cellulitis and/or abscess was enrolled. US was performed by attending physicians or residents who had attended a 30-minute training session in soft tissue US. The treating physician recorded a yes/no assessment of whether he or she believed an abscess was present before and after the US examination. Incision and drainage (I + D) was the criterion standard when performed, while resolution on seven-day follow-up was the criterion standard when I + D was not performed. RESULTS: Sixty-four of 107 patients had I + D-proven abscess, 17 of 107 had negative I + D, and 26 of 107 improved with antibiotic therapy alone. The sensitivity of clinical examination for abscesses was 86% (95% confidence interval [CI] = 76% to 93%), and the specificity was 70% (95% CI = 55% to 82%). The positive predictive value was 81% (95% CI = 70% to 90%), and the negative predictive value was 77% (95% CI = 62% to 88%). The sensitivity of US for abscess was 98% (95% CI = 93% to 100%), and the specificity was 88% (95% CI = 76% to 96%). The positive predictive value was 93% (95% CI = 84% to 97%), and the negative predictive value was 97% (95% CI = 88% to 100%). Of 18 cases in which US disagreed with the clinical examination, US was correct in 17 (94% of cases with disagreement, chi(2) = 14.2, p = 0.0002). CONCLUSIONS: ED bedside US improves accuracy in detection of superficial abscesses.