Date Published

March 28, 2019

Updated For

ALS PCS Version ALS PCS Version 5.2


If patient receives ASA from a certified provider, such as but not limited to other paramedics, doctors/nurses from clinics, are we required to administer another dose of ASA to the ACS patient. Also, does the patient have to have chest pain to administer ASA?


Thank you so much for this question. This brings up a common variance that had been occurring during our audits: ASA being withheld by paramedics because the patient had taken ASA prior to paramedic arrival. This is the reason that we covered this topic in this past years CME (2018). SWORBHPs statement both in the pre-course, and during your simulation cases during the Mandatory CME (STEMI-ROSC case), is that ASA should still be given by paramedics even if the patient has taken it to prior to their arrival. Note that this is the exception to the general rule that medications taken prior to paramedic arrival should be considered.

The reasoning behind this is that ASA has been shown in the ISIS-2 trial (Lancet, 1988)1 to reduce mortality by 23% in cardiac ischemia. As stated in the OBHG Companion Document, ASA is also, a safe medication with a wide therapeutic index (the effective dose without side effects can be from 80mg - 1500mg). The additional dose by the paramedics will not exceed the therapeutic dose while ensuring the correct administration of the correct dose of the medication. Therefore, apply the cardiac ischemia directive as if no care had been rendered prior to your arrival.

In summary: give the ASA.

As for the requirement of chest pain" for ASA administration €“ the quick-and-dirty answer is NO. The Cardiac Ischemia Medical Directive states the indication for treatment is Suspected cardiac ischemia as mentioned in previous Ask MACs (Nov 22, 2012), the Indication of chest pain was changed to suspected cardiac ischemia due to paramedics not administering treatment if the patient described ischemic discomfort as heaviness or tightness. This specific Ask MAC referred to nitroglycerin administration and noted that vague symptoms (weakness, shortness of breath, nausea and vomiting) may be consistent with cardiac ischemia; however, they may also be caused by a myriad of other non-cardiac ischemia conditions. Due to the significant risk of nitroglycerin administration (hypotension) weighed with the limited benefit (symptomatic reduction of chest pain, neutral effect on mortality2,3), the stance of the SWORBHP Medical Directors is that there must be some form of discomfort which is consistent with cardiac etiology in order to meet the indications of suspected cardiac ischemia for nitroglycerin administration. HOWEVER, ASA carries a much lower risk and higher benefit (see above €“ 23% reduction in mortality!) therefore, it is reasonable in the absence of Contraindications for administration to administer ASA in patients without chest discomfort, but other symptoms concerning for cardiac ischemia.

1. ISIS-2 Collaborators. Randomized trial of intravenous streptokinase, oral aspirin, both, or neither among 17,187 cases of suspected acute myocardial infarction: ISIS-2. Second International Study of Infarct Survival. 1988. Lancet. Aug 13;2(8607):349-60. 2. Amersterdam EZ et al. 2014 AHA/ECC Guidelines for the management of patients with Non-STE-Elevation Acute Coronary Syndromes: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014. Dec 23;130(25):2354-94 3. Meine TJ et al. Association of intravenous morphine use and outcomes in Acute Coronary Syndrome: Results form the CRUSADE Quality Improvement Initiative. Am Heart J. 2005. Jun;149(6):1043-9



Cardiac Ischemia

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