Design and retrospective analysis of the Los Angeles Prehospital Stroke Screen (LAPSS)

The therapeutic window for intervention in acute cerebral ischemia is brief. Prehospital identification of acute stroke patients and paramedic administration of neuroprotective agents may soon become critical components of successful acute stroke treatment. This preliminary study sought to demonstrate that a new prehospital screening instrument, the Los Angeles Prehospital Stroke Screen (LAPSS), sensitively identifies acute stroke patients. Further, the study evaluated the potential time savings that could be achieved by paramedic administration of neuroprotective agents in the field.

The authors designed a simple stroke screening tool for use by prehospital personnel, emphasizing motor deficits. They then tested instrument performance and time savings retrospectively, employing data from patients enrolled within six hours of symptom onset in randomized stroke trials at three university-associated paramedic receiving hospitals.

Fifty of 83 patients enrolled in hyperacute stroke trials arrived by ambulance, including 41 with ischemic infarcts and seven with hemorrhages. Of the 41 with acute ischemic stroke, 38 (93%) would have been accurately identified by the LAPSS. For these 38 patients, 1 hour and 50 minutes would have been saved had neuroprotective drug been administered by paramedics at the time of transport vs the actual time of study agent administration in the emergency department.

The LAPSS sensitively identifies ambulance-arriving acute stroke patients, and a substantial time savings will potentially occur if neuroprotective agents are administered by paramedics in the field. The LAPSS is a promising tool that may enable paramedic recognition of stroke with a high degree of sensitivity and simplicity in a short period of time.