Pre-hospital screening & notification shorten time to reperfusion for acute ischaemic stroke

Pre-hospital stroke screening using criteria based on a modified version of the FAST (Face Arm Speech Time) test, together with pre-arrival notification, significantly shortened the door-to-reperfusion therapy time as well as onset-to-door time, door-to–CT time, door-to-needle time, and door-to–groin puncture time for intra-arterial mechanical thrombectomy vs historical control data, study in 298 patients with suspected stroke has shown.

“The typical patient with stroke loses 1.9 million neurons per minute while the stroke remains untreated. Timely reperfusion for ischaemic stroke with intravenous thrombolysis or mechanical thrombectomy can substantially improve patient outcomes,” wrote the researchers from Queen Mary Hospital (QMH). [Stroke 2006;37:263-266; Stroke 2014;45:1053-1058] “Hence, all possible efforts should be made to shorten the stroke onset-to-treatment time.”

In the study, all emergency medical services (EMS) personnel within QMH’s catchment area attended a 2-hour stroke training session in June 2018 delivered by a team of stroke neurologists, neurosurgeons, and emergency physicians. This included didactic instruction concerning stroke subtypes, symptoms, reperfusion therapy pre-hospital management, and hands-on training for utilization of the ambulance stroke assessment scale. The trained EMS personnel screened 298 patients with suspected stroke from July 2018 to October 2019 during ambulance transport prior to hospital arrival. [Hong Kong Med J 2020;26:479-485]

Of these 298 patients, 213 fulfilled the screening criteria, 166 were diagnosed with acute stroke, and 32 received reperfusion therapy. “Pre-hospital stroke screening during ambulance transport by EMS personnel who completed a 2-hour focused training session is effective for identifying reperfusion-eligible patients with stroke,” concluded the researchers.

The stroke onset-to-door time was shortened by more than 1.5 hours with pre-hospital screening and notification vs historical control (100.6 minutes vs 197.6 minutes; p<0.001). The door-to-CT time (25.6 minutes vs 32.0 minutes; p=0.021), door-to-needle time (49.2 minutes vs 70.1 minutes; p=0.003), and door-to–groin puncture time for intra-arterial mechanical thrombectomy (126.7 minutes vs 168.6 minutes; p=0.04) were also significantly shortened after implementation of pre-hospital screening and notification vs historical control data of patients admitted from January 2018 to June 2018, before implementation of the screening system.

Implementation of the screening system also enabled more patients to undergo CT within 25 minutes (68.6 percent vs 51.6 percent; p=0.001) and groin puncture within 120 minutes (72.3 percent vs 18.2 percent; p=0.008).

“The markedly reduced door-to–groin puncture time was likely due to the longer time required to coordinate the neurointerventionist, interventional suite and anaesthesiology care team, which was initiated early with pre-arrival stroke notification,” commented the researchers. “Consistent with our findings, pre-arrival notification is now recommended for all patients with suspected stroke, according to the 2019 guidelines of the American Stroke Association.” [Stroke 2019;50:e344-418]

“One concern related to pre-hospital stroke screening was the potential for overloading the acute stroke treatment pathway … with non-stroke emergencies,” they noted. “To maximize cost-effectiveness, the screening criteria were tailored to reduce notification for patients with stroke mimics and exclude patients who were unlikely to benefit from acute reperfusion therapy. The addition of criteria such as time of onset and pre-morbid functional status enabled prioritization of patients with salvageable stroke for timely reperfusion therapy, and is especially relevant in resource-limited capacity-restricted public healthcare systems.” [Int J Stroke 2020;15:516-520]