Door-to-Needle Optimization in Acute Ischemic Stroke: A Review of Rapid Emergency Department Interventions

Acute ischemic stroke is the second leading cause of death worldwide, and the benefit of intravenous thrombolysis decays steeply with time while its hemorrhagic risk does not. That asymmetry makes the door-to-needle interval, measured from emergency department arrival to administration of the thrombolytic bolus, one of the few determinants of stroke outcome that can be improved without new technology or additional resources. This review synthesizes the evidence underlying door-to-needle optimization. It begins with the quantified biology of delay, in which roughly 1.9 million neurons are lost for every minute of untreated large-vessel ischemia, and with the pooled randomized data showing that the number needed to treat for one additional good outcome rises from approximately five within ninety minutes to approximately fifteen at the outer edge of the 4.5-hour window. It then examines how the interval should be measured, arguing that the mean and the minimum door-to-needle time must both be reported because they describe different properties of the same system. Prehospital determinants of delay, including field triage instruments, dispatcher and paramedic education, prenotification, and ambulance-based thrombolysis, are reviewed alongside the in-hospital Helsinki protocol, whose parallelization of imaging, clinical assessment, and drug preparation reduced median in-hospital delay to twenty minutes and was reproduced in Melbourne within four months. National registry data from the Target: Stroke initiative confirm that these gains scale across a hospital network with concurrent reductions in mortality and symptomatic hemorrhage. The review closes with the trade-off between speed and diagnostic certainty, the reassuring safety profile of thrombolysis in stroke mimics, and the way tenecteplase, imaging-based patient selection, and endovascular thrombectomy are reshaping what the metric measures.