Dispatcher Recognition of Stroke Using the National Academy Medical Priority Dispatch System

Abstract

Background and Purpose— Emergency medical dispatchers play an important role in optimizing stroke care if they are able to accurately identify calls regarding acute cerebrovascular disease. This study was undertaken to assess the diagnostic accuracy of the current national protocol guiding dispatcher questioning of 911 callers to identify stroke (QA Guide version 11.1 of the National Academy Medical Priority Dispatch System). Methods— We identified all Los Angeles Fire Department paramedic transports of patients to University of California Los Angeles Medical Center during the 12-month period from January to December 2005 in a prospectively maintained database. Dispatcher-assigned Medical Priority Dispatch System codes for each of these patient transports were abstracted from the paramedic run sheets and compared to final hospital discharge diagnosis. Results— Among 3474 transported patients, 96 (2.8%) had a final diagnosis of stroke or transient ischemic attack. Dispatchers assigned a code of potential stroke to 44.8% of patients with a final discharge diagnosis of stroke or TIA. Dispatcher identification of stroke showed a sensitivity of 0.41, specificity of 0.96, positive predictive value of 0.45, and negative predictive value of 0.95. Conclusions— Dispatcher recognition of stroke calls using the widely employed Medical Priority Dispatch System algorithm is suboptimal, with failure to identify more than half of stroke patients as likely stroke. Revisions to the current national dispatcher structured interview and symptom identification algorithm for stroke may facilitate more accurate recognition of stroke by emergency medical dispatchers.

Emergency Stroke Calls: Obtaining Rapid Telephone Triage (ESCORTT) – a programme of research to facilitate recognition of stroke by emergency medical dispatchers

“…[7][8][9] If this is to be increased, it is necessary to identify those symptoms likely to have a high sensitivity in relation to a final diagnosis of stroke. The characteristics with the highest sensitivities were having no to only slight pre-stroke disability, and being alert.…”

“…4 However, delays in presentation and specialist assessment frequently prevent patients from receiving rtPA. Emergency medical dispatch sensitivity and positive predictive value (PPV) for identifying stroke is < 50%, [7][8][9] and this is compounded by long delays in patients accessing emergency medical services (EMSs). 10 Studies have shown that activation of the EMSs is the single most important factor in the rapid triage and treatment of acute stroke patients.…”

“…Published reports on the ability of EMDs to recognise stroke from callers' descriptions suggest that EMD sensitivity and PPV for identifying stroke are < 50%. [7][8][9] Therefore, improving the communication between EMDs and callers to increase the likelihood that stroke is recognised would promote the initiation of the pre-hospital pathways that are known to expedite patients' access to specialist assessment and treatment. 27 There is evidence to suggest that the EMSs are more likely to be contacted by the public for suspected stroke if the person's symptoms include speech problems, weakness, decreased level of consciousness and dizziness/loss of co-ordination.…”

Stroke and the emergency medical services – enhancing performance within the chain of survival

“…The ambulance crews successfully priority transport remained at only a small fraction below 90% (Table 15). , Buck et al 2009, Krebes et al 2012, Jones et al 2013) and prehospital stroke care. However, even for these eventually recanalized patients there still remains some room for improvement as the assignment of calls to high priority and stroke code status in dispatch and transportation did not reach 100%.…”

The Revised Telephonic Triage of New Jersey and Conventional Method of Triage by Emergency Medical Dispatchers of Qom Emergency Medical Services, Iran, in 2012: A Comparative Investigation

“…Some studies are done in this regard, indicating that operators did not diagnose serious medical problems. One of the aims of medical emergency systems is making a balance between available resources to provide for the patients and the amount of patients' need to them (10)(11)(12).…”