Skip to content


  • Letter to the Editors
  • Open Access

Letter to the editors: the potential role for prehospital thrombolysis and time-critical stroke transfers in the northern Norway aeromedical retrieval system; In response to: Norum J, Elsbak TM: Air ambulance services in the Arctic: a Norwegian study. Int J Emerg Med 2011, 4:1

International Journal of Emergency Medicine20114:45

  • Received: 1 June 2011
  • Accepted: 26 July 2011
  • Published:


The role for prehospital thrombolysis for ST-elevation acute myocardial infarction and time-critical stroke transfers in the northern Norway aeromedical retrieval system as well as the aero-evacuation impact of increased Arctic expedition tourism could benefit from further discussion by Norum and Elsbak. Close ECG surveillance for ST elevation and retrieval thrombolysis en route to the accepting hospital could be of benefit for acute coronary syndrome patients in northern Norway who require prolonged aeromedical transfer. For patients who remain within a reasonable time frame for stroke thrombolysis (up to 4.5 h after symptom onset), expedited transfer for neuroimaging to determine eligibility is recommended.


  • Alteplase
  • Acute Coronary Syndrome Patient
  • Intravenous Alteplase
  • Arctic Expedition
  • Elevation Acute Myocardial Infarction

Letter to the Editors

Norum and Elsbak describe the clinical and transfer characteristics of fixed and rotary wing aeromedical retrievals carried out in northern Norway for the 10 years 1999-2009 [1]. Acute cardiovascular diagnoses were encountered in 76/345 (22%) of the transported cohort [1, 2], although it is not stated which, if any, of these patients suffered high-risk acute coronary syndromes (ACS) and/or ST elevation acute myocardial infarction (STEMI). With one in five of the transported cohort potentially having a STEMI or high-risk ACS, a lengthy 3 h 33 min one-way transfer time [1] and attendant delays to accessing primary percutaneous reperfusion, Norum and Elsbak's study could have discussed the role of early recognition of ST elevation and prehospital thrombolysis. Prehospital ECG recognition of STEMI is reliable [3], and prehospital thrombolysis is safe [4] and acutely as clinically beneficial as primary angioplasty if transfer times are anticipated to exceed 120 min from onset of chest pain [57], a situation that applies to Norum and Elsbak's study cohort. Furthermore, in high-risk ACS, close ECG surveillance for attainment of lysis criteria followed by timely prehospital thrombolysis could mitigate further ST elevation (and the extent of myocardial injury) during transport [8].

Despite the apparent absence of neurological/stroke patients in their 10-year retrieval registry, Norum and Elsbak's [1] emphasis on urgent aeromedical transfer to identify stroke patients suitable for thrombolysis is to be applauded. Stroke lysis with intravenous alteplase remains beneficial when administered at up to 4.5 h after symptom onset [9, 10], a time range that remains relevant within the approximately 3.5 h mean transfer time encountered in the northern Norwegian aeromedical system. That rapidly aging adult populations in advanced economies will give rise to increased stroke burden is borne out by the transport of 69 stroke patients among 504 patients (14%) recently retrieved by a single agency German aeromedical service [11].

Norum and Elsbak [1] speculate that increasing expedition ship tourist traffic to Arctic Norway could lead to an increased need for aeromedical evacuation. However, most expedition ships operating in the Arctic are currently physician-staffed, with non-life or limb-threatening respiratory, gastrointestinal, dermatological, musculoskeletal complaints as well as minor trauma being the most frequently encountered health complaints [12]. Cardiovascular and neurological events, emergency evacuation, need for hospitalization as well as unexpected deaths are rarely encountered despite travelers being older, suggesting effective pre-trip medical screening [12]. At this stage it remains uncertain whether more Arctic tourism will necessarily increase aeromedical workload; this has been my experience as ship's physician in Svalbard in July and August 2009, when there was only one case of shipboard IV rehydration required for non-specific enteritis.



acute coronary syndromes


ST elevation acute myocardial infarction.


Authors’ Affiliations

Careflight Medical Services, Brisbane, 4000, Australia


  1. Norum J, Elsbak TM: Air ambulance services in the Arctic: a Norwegian study. Int J Emerg Med 2011, 4: 1. [] 10.1186/1865-1380-4-1PubMed CentralView ArticlePubMedGoogle Scholar
  2. Norum J: Cardiovascular disease (CVD) in the Norwegian Arctic: Air ambulance operations 1999–2009 and future challenges in the region. Int Marit Health 2010, 62: 117–22.PubMedGoogle Scholar
  3. Barbagelata A, Perna ER, Clemmensen P, Uretsky BF, Canella JP, Califf RM, Granger CB, Adams GL, Merla R, Birnbaum Y: Time to reperfusion in acute myocardial infarction. It is time to reduce it! J Electrocardiol 2007, 40: 257–64. 10.1016/j.jelectrocard.2007.01.007View ArticlePubMedGoogle Scholar
  4. Welsh RC, Travers A, Senaratne M, Williams R, Armstrong PW: Feasibility and applicability of paramedic-based prehospital thrombolysis in a large North American center. Am Heart J 2006, 152: 1007–14. 10.1016/j.ahj.2006.06.022View ArticlePubMedGoogle Scholar
  5. Steg PG, Bonnefoy E, Chabaud S, Lapostolle F, Dubien BY, Cristofini P, Leizorovisz A, Touboul P, for the Comparison of Angioplasty and Prehospital Thrombolysis in acute Myocardial infarction (CAPTIM) Investigators: Impact of time to treatment on mortality after prehospital fibrinolysis or primary angioplasty: data from the CAPTIM randomized clinical trial. Circulation 2003, 108: 2851–6. 10.1161/01.CIR.0000103122.10021.F2View ArticlePubMedGoogle Scholar
  6. Danchin N, Blanchard D, Steg PG, Sauval P, Hanania G, Goldstein P, Cambou JP, Gueret P, Vaur L, Boutalbi Y, Genes N, Lablanche JM, USIC 2000 Investigators: Impact of prehospital thrombolysis for acute myocardial infarction on 1-year outcome: results from the French Nationwide USIC 2000 Registry. Circulation 2004, 110: 1909–15. 10.1161/01.CIR.0000143144.82338.36View ArticlePubMedGoogle Scholar
  7. Morrison LJ, Verbeek PR, McDonald AC, Sawadsky BV, Cook DJ: Mortality and prehospital thrombolysis for acute myocardial infarction: A meta-analysis. JAMA 2000, 283: 2686–92. 10.1001/jama.283.20.2686View ArticlePubMedGoogle Scholar
  8. Lamfers EJ, Hooghoudt TE, Hertzberger DP, Schut A, Stolwijk PW, Verheugt FW: Abortion of acute ST segment elevation myocardial infarction after reperfusion: incidence, patients' characteristics, and prognosis. Heart 2003, 89: 496–501. 10.1136/heart.89.5.496PubMed CentralView ArticlePubMedGoogle Scholar
  9. Lees KR, Bluhmki E, von Kummer R, Brott TG, Toni D, Grotta JC, Albers GW, Kaste M, Marler JR, Hamilton SA, Tilley BC, Davis SM, Donnan GA, Hacke W, for the ECASS EPITHET rt-PA Group Investigators: Time to treatment with intravenous alteplase and outcome in stroke: an updated pooled analysis of ECASS, ATLANTIS, NINDS, and EPITHET trials. Lancet 2010, 375: 1695–1703. 10.1016/S0140-6736(10)60491-6View ArticlePubMedGoogle Scholar
  10. Hacke W, Kaste M, Bluhmki E, Brozman M, Davalos A, Guidetti D, Larrue V, Lees KR, Medeghri Z, Machnig T, Schneider D, von Kummer R, Wahlgren N, Toni D, for the European Cooperative Acute Stroke Study (ECASS) Investigators: Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke. New Engl J Med 2008, 359: 1317–29. 10.1056/NEJMoa0804656View ArticlePubMedGoogle Scholar
  11. Sand M, Bollenbach M, Sand D, Lotz H, Thrandorf C, Cirkel C, Altmeyer P, Bechara FG: Epidemiology of aeromedical evacuation: An analysis of 504 cases. J Travel Med 2010, 17: 405–9. 10.1111/j.1708-8305.2010.00454.xView ArticlePubMedGoogle Scholar
  12. Shaw MTM, Leggat PA: Illness and injury to travellers on a premium expedition to Iceland. Travel Med Infectious Disease 2008, 6: 148–51. 10.1016/j.tmaid.2008.02.003View ArticleGoogle Scholar


© Ting; licensee Springer. 2011

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.