Is routine coagulation testing necessary in patients presenting to the emergency department with chest pain?

BACKGROUND: Driven by the need for rapid assessment, treatment and appropriate disposition of patients in the emergency department (ED), blood tests are often performed in a protocolised fashion before full clinical assessment. The cardiologists at this institution currently insist upon a coagulation profile in each patient referred with a possible acute coronary syndrome.
METHODS: A retrospective cohort of 1000 consecutive patients presenting to the ED with chest pain was identified. If performed, the international normalised ratio (INR) and the activated partial thromboplastin time ratio (APTR) were retrieved for each patient. If no coagulation sample was sent from the ED, a search was performed to determine whether a sample was sent within the subsequent 24-h period by the admitting hospital team. A cause of a raised INR or APTR that could have been identified easily at initial patient assessment in the ED was sought.
RESULTS: 640 patients were identified who had coagulation tests sent from the ED as part of their assessment. Of the 592 coagulation samples successfully processed 79 were abnormal. All of these abnormal tests could have been predicted on the basis of a history of warfarin or heparin use or a history of liver disease, or were trivial enough to not preclude coronary angiography or the therapeutic use of heparin.
CONCLUSION: Routine coagulation testing in adults presenting to ED with chest pain is unnecessary. This practice should be replaced by a coagulation testing policy based on an increased risk of coagulopathy due to warfarin or heparin use or a history of liver disease.