Treatment of suspected cardiac ischemia with aspirin by paramedics in an urban emergency medical services system.

Background: Aspirin (ASA) has unquestioned benefit to patients with cardiac ischemia. Previous studies indicate health care providers may not adequately treat patients experiencing cardiac ischemia with ASA.

Objective: To determine the rate of ASA use for patients being treated for chest pain suggestive of cardiac ischemia in the prehospital setting.

Methods: This was a retrospective study of paramedic encounters identified through billing records for all patients receiving the combination of an intravenous catheter, supplemental oxygen, and cardiac monitoring from November 2001 to January 2002. Prehospital medical records were reviewed in order to determine the proportion of patients with suspected cardiac ischemia who received ASA. The setting was a single prehospital emergency medical services system serving an urban population.

Results: A total of 2,457 paramedic encounters were reviewed over a three-month period. Two hundred thirty-two patients were assessed as having cardiac ischemia, of whom 169 (73%) had no absolute or relative contraindication to ASA. Of the 169 patients, only 92 (54%) received ASA. Of the 99 patients, who received nitroglycerin for presumed cardiac ischemia and had no contraindication to receiving ASA, only 78 (79%) received ASA. Of the 453 patients complaining of nontraumatic chest pain and without a contraindication, 157 (35%) received ASA.

Conclusions: Paramedics do not use ASA optimally and may choose therapies with less proven benefit.