Door-to-Needle and Door-to-Door Time Definitions
Door-to-needle (DTN) time is the interval from hospital arrival to initiation of intravenous alteplase administration in acute ischemic stroke patients, while "door-to-door" time is not a standard metric in stroke care terminology.
Door-to-Needle Time
DTN time specifically measures the critical window from when a stroke patient arrives at the emergency department until thrombolytic therapy (alteplase/tPA) begins flowing through the IV 1. This is the most important time metric in acute stroke management because alteplase effectiveness is highly time-dependent.
Current Performance Goals
The 2018 AHA/ASA guidelines establish clear benchmarks 1:
- Primary goal: DTN time ≤60 minutes in ≥50% of acute ischemic stroke patients (Class I recommendation)
- Secondary goal: DTN time ≤45 minutes in ≥50% of patients (Class IIb recommendation)
Recent data shows significant improvement in achieving these targets. In GWTG-Stroke hospitals, the median DTN time decreased from 77 minutes (2003-2009) to 67 minutes (2010-2013), with the percentage of patients treated within 60 minutes increasing from 26.5% to 41.3% 1. More recent quality improvement initiatives have achieved even better results, with some centers reaching median DTN times of 26 minutes and 92.64% of patients treated within 60 minutes 2.
DTN Time Components
Recent research has deconstructed DTN time into distinct workflow intervals to identify specific delays 3, 4:
- Door-to-order time (ODT): Arrival to physician order
- Order-to-imaging completion time (OCT): Order to CT/MRI completion
- Imaging completion-to-consent time (ICT): Results to patient/family consent (strongest correlation with overall DTN delays)
- Consent-to-needle time (CNT): Consent to actual drug administration
"Door-to-Door" Time - Not a Standard Metric
The term "door-to-door" does not appear in the 2018 AHA/ASA guidelines or standard stroke literature 1. You may be thinking of:
- Onset-to-door time: Symptom onset to hospital arrival (median 36 minutes for EMS transport) 1
- Onset-to-needle time: Symptom onset to alteplase initiation (median 141-145 minutes historically) 1
- Door-to-imaging time: Hospital arrival to CT/MRI completion (goal ≤25 minutes) 1
Common Pitfall
Do not confuse "door-to-door" with "drip-and-ship" scenarios, where patients receive alteplase at one facility before transfer to a comprehensive stroke center for endovascular therapy. This involves separate time metrics for each facility.