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Diagnostic performance and potential clinical impact of advanced care paramedic interpretation of ST-segment elevation myocardial infarction in the field

Published online by Cambridge University Press:  21 May 2015

Michel R. Le May*
Affiliation:
University of Ottawa Heart Institute, Ottawa, Ont
Richard Dionne
Affiliation:
Ottawa Base Hospital Program, Ottawa, Ont Department of Emergency Medicine, University of Ottawa, Ottawa, Ont
Justin Maloney
Affiliation:
Ottawa Base Hospital Program, Ottawa, Ont Department of Emergency Medicine, University of Ottawa, Ottawa, Ont
John Trickett
Affiliation:
Ottawa Base Hospital Program, Ottawa, Ont
Irene Watpool
Affiliation:
Ottawa Base Hospital Program, Ottawa, Ont
Michel Ruest
Affiliation:
Ottawa Paramedic Service, Ottawa, Ont
Ian Stiell
Affiliation:
Department of Emergency Medicine, University of Ottawa, Ottawa, Ont
Sheila Ryan
Affiliation:
University of Ottawa Heart Institute, Ottawa, Ont
Richard F. Davies
Affiliation:
University of Ottawa Heart Institute, Ottawa, Ont
*
Ottawa Heart Institute, 40 Ruskin St., Ottawa ON K1Y 4W7

Abstract

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Objectives:

Most studies of pre-hospital management of ST-elevation myocardial infarction (STEMI) have involved physicians accompanying the ambulance crew, or electrocardiogram (ECG) transmission to a physician at the base hospital. We sought to determine if Advanced Care Paramedics (ACPs) could accurately identify STEMI on the pre-hospital ECG and contribute to strategies that shorten time to reperfusion.

Methods:

A STEMI tool was developed to: 1) measure the accuracy of the ACPs at diagnosing STEMI; and 2) determine the potential time saved if ACPs were to independently administer thrombolytic therapy. Using registry data, we subsequently estimated the time saved by initiating thrombolytic therapy in the field compared with in-hospital administration by a physician.

Results:

Between August 2003 and July 2004, a correct diagnosis of STEMI on the pre-hospital ECG was confirmed in 63 patients. The performance of the ACPs in identifying STEMI on the ECG resulted in a sensitivity of 95% (95% confidence interval [CI] 86%–99%), a specificity of 96% (95% CI 94%–98%), a positive predictive value (PPV) of 82% (95% CI 71%–90%), and a negative predictive value (NPV) of 99% (95% CI 97%–100%). ACP performance for appropriately using thrombolytic therapy resulted in a sensitivity of 92% (95% CI 78%–98%), a specificity of 97% (95% CI 94%–98%), a PPV of 73% (95% CI 59%–85%) and an NPV of 99% (95% CI 97%–100%). We estimated that the median time saved by ACP administration of thrombolytic therapy would have been 44 minutes.

Conclusions:

ACPs can be trained to accurately interpret the pre-hospital ECG for the diagnosis of STEMI. These results are important for the design of regional integrated programs aimed at reducing delays to reperfusion.

Type
Original Research • Recherche originale
Copyright
Copyright © Canadian Association of Emergency Physicians 2006

References

1.Effectiveness of intravenous thrombolytic treatment in acute myocardial infarction. Gruppo Italiano per lo Studio della Streptochinasi nell’Infarto Miocardico (GISSI). Lancet 1986;1:397402.Google Scholar
2.Berger, PB, Ellis, SG, Holmes, DR Jr, et al. Relationship between delay in performing direct coronary angioplasty and early clinical outcome in patients with acute myocardial infarction: results from the global use of strategies to open occluded arteries in Acute Coronary Syndromes (GUSTO-IIb) trial. Circulation 1999;100:1420.Google Scholar
3.Canto, JG, Rogers, WJ, Bowlby, LJ, et al. The prehospital electrocardiogram in acute myocardial infarction: Is its full potential being realized? National Registry of Myocardial Infarction 2 Investigators. J Am Coll Cardiol 1997;29:498505.CrossRefGoogle Scholar
4.Terkelsen, CJ, Norgaard, BL, Lassen, JF, et al. Prehospital evaluation in ST-elevation myocardial infarction patients treated with primary percutaneous coronary intervention. J Electrocardiol 2005;38(suppl):187–92.Google Scholar
5.Aufderheide, TP, Hendley, GE, Thakur, RK, et al. The diagnostic impact of prehospital 12-lead electrocardiography. Ann Emerg Med 1990;19:1280–7.CrossRefGoogle ScholarPubMed
6.Grim, P, Feldman, T, Martin, M, et al. Cellular telephone transmission of 12-lead electrocardiograms from ambulance to hospital. Am J Cardiol 1987;60:715–20.CrossRefGoogle ScholarPubMed
7.Whitbread, M, Leah, V, Bell, T, et al. Recognition of ST elevation by paramedics. Emerg Med J 2002;19:66–7.Google Scholar
8.Massel, D, Dawdy, JA, Melendez, LJ. Strict reliance on a computer algorithm or measurable ST segment criteria may lead to errors in thrombolytic therapy eligibility. Am Heart J 2000;140:221–6.CrossRefGoogle ScholarPubMed
9.Morrow, DA, Antman, EM, Sayah, A, et al. Evaluation of the time saved by prehospital initiation of reteplase for ST-elevation myocardial infarction: results of The Early Retavase-Thrombolysis in Myocardial Infarction (ER-TIMI) 19 trial. J Am Coll Cardiol 2002;40:71–7.CrossRefGoogle Scholar
10.Wallentin, L, Goldstein, P, Armstrong, PW, et al. Efficacy and safety of tenecteplase in combination with the low-molecular weight heparin enoxaparin or unfractionated heparin in the prehospital setting: the Assessment of the Safety and Efficacy of a New Thrombolytic Regimen (ASSENT)-3 PLUS randomized trial in acute myocardial infarction. Circulation 2003;108:135–42.CrossRefGoogle ScholarPubMed
11.Feasibility, safety, and efficacy of domiciliary thrombolysis by general practitioners: Grampian region early anistreplase trial. GREAT Group. BMJ 1992;305:548–53.Google Scholar
12.Prehospital thrombolytic therapy in patients with suspected acute myocardial infarction. The European Myocardial Infarction Project Group. N Engl J Med 1993;329:383–9.CrossRefGoogle Scholar
13.Castaigne, AD, Herve, C, Duval-Moulin, AM, et al. Prehospital use of APSAC: results of a placebo-controlled study. Am J Cardiol 1989;64:30A-3A.CrossRefGoogle ScholarPubMed
14.Roth, A, Barbash, GI, Hod, H, et al. Should thrombolytic therapy be administered in the mobile intensive care unit in patients with evolving myocardial infarction? A pilot study. J Am Coll Cardiol 1990;15:932–6.Google Scholar
15.Schofer, J, Buttner, J, Geng, G, et al. Prehospital thrombolysis in acute myocardial infarction. Am J Cardiol 1990;66:1429–33.CrossRefGoogle ScholarPubMed
16.Weaver, WD, Cerqueira, M, Hallstrom, AP, et al. Prehospital-initiated vs hospital-initiated thrombolytic therapy. The Myocardial Infarction Triage and Intervention Trial. JAMA 1993;270:1211–6.CrossRefGoogle ScholarPubMed
17.Morrison, LJ, Verbeek, PR, McDonald, AC, et al. Mortality and prehospital thrombolysis for acute myocardial infarction: a meta-analysis. JAMA 2000;283:2686–92.Google Scholar
18.Sejersten, M, Young, D, Clemmensen, P, et al. Comparison of the ability of paramedics with that of cardiologists in diagnosing ST-segment elevation acute myocardial infarction in patients with acute chest pain. Am J Cardiol 2002;90:995–8.Google Scholar
19.Whitbread, M, Leah, V, Bell, T, et al. Recognition of ST elevation by paramedics. Emerg Med J 2002;19:66–7.Google Scholar
20.Sandler, DA. Call to needle times after acute myocardial infarction. Paramedics in Derbyshire can admit direct to coronary care unit when they diagnose myocardial infarction [letter]. BMJ 1999;318:1553–4.Google Scholar
21.Pitt, K. Prehospital selection of patients for thrombolysis by paramedics. Emerg Med J 2002;19:260–3.CrossRefGoogle ScholarPubMed
22.Keeling, P, Hughes, D, Price, L, et al. Safety and feasibility of prehospital thrombolysis carried out by paramedics. BMJ 2003;327:27–8.Google Scholar
23.Canto, JG, Zalenski, RJ, Ornato, JP, et al. Use of emergency medical services in acute myocardial infarction and subsequent quality of care: observations from the National Registry of Myocardial Infarction 2. Circulation 2002;106:3018–23.CrossRefGoogle Scholar