NASHVILLE—About 25% of patients with ischemic stroke who receive thrombolysis do so in the field before hospital transfer with the “drip-and-ship” paradigm, according to research presented at the 2015 International Stroke Conference.
Although researchers observed modest differences in clinical outcome between these patients and those treated after admission to an emergency department, drip-and-ship may increase the overall use of t-PA, said Kevin N. Sheth, MD, Associate Professor of Neurology and Assistant Professor of Neurosurgery at Yale University in New Haven, Connecticut.
The retrospective analysis, which was published online ahead of print February 11 in Stroke, examined data from the Get With the Guidelines registry to evaluate trends over time in the use of t-PA and drip-and-ship administration in the United States. The study involved 1,440 hospitals and 44,667 patients who had an ischemic stroke during 2003–2010 and received t-PA. Of these people, 10,475 (23.5%) received t-PA in the field before optional admission and within three hours of symptom onset.
The NIH Stroke Scale (NIHSS) score was significantly higher among patients who presented for hospital treatment, compared with patients who did not (12.9 vs 11). However, these patients were seen before t-PA administration, while the drip-and-ship group already had been treated. This temporal difference could account for the discrepancy in scores, said Dr. Sheth.
Hospitals that employed drip-and-ship had significantly higher rates of stroke patients treated each year, as well as more beds. More of those hospitals were teaching facilities or were designated as primary stroke centers.
Drip-and-ship frequency was stable during the study period. About 25% of all eligible patients received field thrombolysis in 2003 and 2010. Among patients treated at the hospital, the frequency of t-PA administration within three hours of stroke onset increased from approximately 11% in 2003 to 25% in 2010. In contrast, the percentage of timely thrombolysis in drip-and-ship patients changed little (ie, from approximately 5% to 9%) during the same period.
Overall inpatient mortality was 10%, but was slightly higher among drip-and-ship patients (10.93% vs 9.67%). Symptomatic intracranial hemorrhage occurred in 5.79% of people treated with drip-and-ship and 5.22% of people treated in the hospital. Nearly the same percentage of patients in both groups walked independently at discharge (38.4% vs 38.8%) and was discharged home (40.3% vs 40.6%).
Among the hospital-treated patients, fewer than 4% underwent endovascular therapy. In contrast, 7% of drip-and-ship patients had endovascular therapy. Patients who received endovascular treatment had higher median NIHSS scores at t-PA administration than those who did not (17 vs 12). Endovascular treatment was significantly associated with higher mortality (20% vs 10%) and intracranial hemorrhage (11% vs 5%).
In a multivariate analysis that adjusted for NIHSS score, in-hospital mortality was significantly more likely in drip-and-ship patients (odds ratio [OR], 1.23). Those patients also were significantly less likely to walk independently at discharge (OR, 0.66) and to be discharged home (OR, 0.66). Intracranial hemorrhage was significantly more likely in drip-and-ship patients (OR, 1.4), as was a hospital stay of longer than four days (OR, 1.20).
—Michele G. Sullivan