Review of: Welsh R, Travers A, Senaratne M, et al: "Feasibility and applicability of paramedic-based prehospital fibrinolysis in a large North American center." American Heart Journal. 152(6):1007-1014, 2006
By now, everyone should be convinced of the value of prehospital 12-leads in identifying the STEMI patient who may benefit from either fibrionolytics or interventional cardiology. The controversy now is what if any potential exists for administering fibrinolotyics by paramedics prior to arrival at the hospital.
This study from Canada had paramedics perform 12-leads and transmit them to a physician who would then review it and go over the patient's history to determine whether or not they were candidates for fibrinolytics. The patient was then randomized to either get the "clot buster" in the field or wait until they arrived at the hospital.
Time to treatment was of course reduced by prehospital administration from 2:38 minutes to 1:43 minutes. There was no difference in complication rates or mortality between the two groups. In fact, patients who received prehospital fibrinolytics had lower peak levels of creatine kinase and Q waves at discharge, meaning that they had less damage to their heart.
Their conclusion was that prehospital is not only feasible but may be beneficial over conventional therapy.
This is the first large scale study examining the potential role for prehospital fibrinolytic therapy. Clearly, with proper medical oversight and transmission of 12-leads, paramedics can be trained and educated to administer the agents.
However, this study raises some interesting questions that can only be answered by understanding the system. For example, why was the reduction in time to treatment almost an hour? Was transport time an hour longer? Or if not, then why would it take that long for the hospitals to get the agents administered? What would the time to treatment have been if the 12-lead had been transmitted to the receiving facility?
Interestingly, of the 65 patients that were excluded from prehospital fibrinolytic administration, almost half either had a left bundle branch block, inadequate history or were hypertensive. I would like to know how many of those patients subsequently received agents in the hospital.
While this study proves the potential utility for prehospital fibrinolytics, there are many questions that need to be answered to determine whether it makes sense for your system.