Door-to-Needle Time and the Proportion of Patients Receiving Intravenous Thrombolysis in Acute Ischemic Stroke

Abstract

Intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator (rt-PA) is one of very few effective treatments for acute ischemic stroke. Still, in most centers, only a small proportion (2%–7%) of patients with ischemic stroke receive this treatment in daily practice.1–3 The most important factor limiting IVT administration is time because it has to be administered within 4.5 hours of symptom onset. Even within this time window, the clinical benefit from IVT declines rapidly (time is brain), and every minute counts.4 If IVT is started within 90 minutes after stroke onset, the number of patients needed to treat to achieve an excellent clinical outcome modified Rankin scale score (0–1) is 4. Within the 180–270-minute time window, this number dramatically increases to 14.5 In other words, a shorter delay from symptom to IVT, the so-called symptom-to-needle time, can make the difference between being independent and being dependent. Reducing the symptom-to-needle time requires several hurdles to be jumped. Most time is lost in the prehospital period, the so-called symptom-to-door time to symptom-to-needle time, mainly because of patients waiting before they seek medical attention. However, this is difficult to accomplish because campaigns aimed at raising public awareness of stroke symptoms have only limited impact on behavior.6 Inside the hospital, focus should be on decreasing the time from arrival to IVT administration, the so-called door-to-needle time (DNT). Besides improved functional outcome, a reduced DNT will also increase the proportion of patients eligible for IVT because more patients can be treated before the 4.5-hour time limit.7 Unfortunately, >15 years after IVT was proven to be clinically effective, in most institutions, the DNT is still >60 minutes for the majority of patients.7,8 In most countries, national guidelines recommend that the DNT should not exceed this 60-minute limit. …