In treating ischemic stroke, door-to-needle times are important for providing stroke patients with tissue plasminogen activator (tPA). However, the time between imaging the brain and initiating therapy appears to the most vulnerable to potential delays.

In a study published online July 14 in JAMA: Neurology, researchers explored the two segments of time that make up the span between when a patient enters the hospital to when he or she is treated with tPA. Professional guidelines state that optimal treatment of ischemic stroke occurs during a 60-minute window of time. Within that timeframe, the patient experiences a period called “door-to-imaging” time and then “imaging-to-needle” time.

Kori Sauser, MD, MSc, of the University of Michigan in Ann Arbor, and colleagues suspected that the longer period would be the wait from door-to-imaging, but they found that the length of time from when the patient was imaged to when he or she received treatment was by far the most susceptible to lag. The research team noted that imaging occurred in 68.4 percent of patients within 25 minutes. However, the mean imaging-to-needle time was 60.1 minutes and the mean door-to-needle time was 82.9 minutes.

Only 28.7 percent of patients received tPA within the 60-minute window, which was consistent with earlier studies.

Recognized severity of the stroke prior to imaging influenced how quickly resources were initially martialed to care for patients. However, Sauser et al noted that severity did little to continue speed in the ultimate goal of treatment with tPA.

These findings are in spite of efforts to highlight and address choke points and delays in the care process. In part, this appears to be due to the number of individual choke points, such as medical decision making, stroke team notification, determination of tPA eligibility, preparation of tPA, and interpretation and discussion of image findings.

Sauser et al admitted that communication among hospital staff and between doctors, patients and patients’ families is extremely important to outcomes, but to optimize and speed treatment more needs to be done to reduce the amount of time lost in this critical period. The researchers strongly recommended focusing efforts on changes to hospital policy to reduce the overall time before stroke patients received treatment.