José G. Merino, MD, MPhil


June 18, 2013

In This Article

The Prognostic Value of Early Post-tPA Clinical Changes

Patients treated with intravenous tPA often have clinical changes, for better or worse, soon after the treatment is given. Two studies presented at the meeting suggest that these changes may predict long-term outcome. Neal Rao and colleagues[8] from the University of California, Los Angeles, found that among the 624 patients in the National Institute of Neurological Disorders and Stroke tPA trials, those with early neurologic deterioration were more likely to have poor 90-day outcomes, particularly if early neurologic deterioration was associated with hemorrhage. Conversely, Nicolas Bianchi and colleagues[9] found that among 316 patients treated with intravenous tPA, those who had early neurologic improvement (reduction of NIHSS score > 8 or NIHSS score of 0-1 at 24 hours) were more likely to have a good outcome at 90 days.

Access to tPA

Although tPA was approved by the US Food and Drug Administration more than 15 years ago, many patients with stroke do not receive this treatment. When they examined patterns of tPA use over 11 years in 6064 hospitals, Yogesh Moradiya and colleagues[10] found that only 2.1% of stroke patients were treated with intravenous tPA. Hospitals that had a neurology residency program had a higher rate of use (3.8%) than nonteaching hospitals, and the rate of tPA administration over the years increased at a slower rate at hospitals without training programs.

Streamlining stroke systems of care can lead to more timely administration of tPA, and perhaps to better outcomes. Several steps can reduce time to treatment. Emergency medical services (EMS), for example, can play a key role in the stroke chain of survival, as highlighted in a study by Michael Ruff and colleagues.[11] They found that among 40 patients transported by EMS, prearrival notification reduced door-to-decision time because of efficient use of stroke team, CT, and laboratory services, and when EMS drew blood en route, door-to-needle time decreased by 8 minutes.

Regionalizing stroke care is another intervention that may improve the quality care at the community level. Syed F. Ali and colleagues[12] analyzed data from 1832 patients with stroke treated at their institution and compared in-hospital mortality for patients who arrived directly at their hospital and the 52% patients of who were transferred from another institution. Despite the latter having more severe strokes, the in-hospital mortality rate was the same in both groups.

Although intravenous tPA can reduce disability after stroke, it is not available in many countries, a fact highlighted by Manoj Mittal and colleagues.[13] They conducted a systematic search of the literature looking for all reports of tPA use and found reports from 54 (25%) of the 214 countries in the world. Countries reporting tPA use were more likely to have higher income status -- 3% of low, 13% of low-middle, 28% of upper-middle, and 44% of high-income countries reported tPA use. Not surprisingly, even within these income groups, countries with higher per-capita expenditure on health were more likely to report tPA use.

Other Therapies

Aneesh Singhal[14] presented data from a phase 2b clinical trial of normobaric oxygen (NBO) therapy for patients with stroke, conducted at several SPOTRIAS sites. The investigators enrolled 60 patients within 9 hours of onset of symptoms who were ineligible for standard tPA and randomly assigned them to receive 8 hours of NBO or room air. Because this was a proof-of-principle study, the investigators looked at a surrogate outcome: changes in lesion growth on MRI. The NBO did not have an effect on infarct growth, but patients treated with NBO were more likely to have reversal of the apparent diffusion coefficient changes during the therapy. It is unclear from these results whether further studies will be performed.

After the INS, I felt that we had achieved our objective of providing a state-of-the art survey of new scientific approaches to stroke and heard from active investigators in the field about new interventions that may lead to better outcomes for our patients.