2025 Southeastern Residency Conference

Title: Evaluation of intravenous thrombolytic administration for acute ischemic stroke in patients with NIHSS score 0-5


Authors: Xuyen Nguyen, Parth Parikh, Morgan Weithman, Haley Smith, Jamie Wagner, Michael Loewe, Victoria Fontenot, Amy booth, Jamie Landry, Lynette 
Obey, and Greggory Davis


Objective: To evaluate the safety and efficacy of intravenous thrombolytic therapy in stroke patients with NIHSS 0-5 


Background: Approximately 87% of all stroke cases are acute ischemic stroke (AIS), and 13% are hemorrhagic. Current guidelines recommend intravenous 
thrombolytic (IVT) therapy in patients with AIS who present within 4.5 hours of severe or disabling symptoms. However, more than 50% of patients with AIS 
present with mild or minor symptoms (with a National Institute of Health Stroke Score, or NIHSS, of 0-5), and the guidelines do not have a strong 
recommendation for the use of IVT therapy in this patient population due to conflicting evidence. Therefore, this research project aims to determine the efficacy and safety of IVT therapy in patients with an initial NIHSS of 0-5.


Methods: A retrospective chart review was performed to identify patients admitted to the Franciscan Missionaries of Our Lady Health System and St. Dominic 
Jackson Memorial Hospital between 01/01/2020 and 12/31/2024. Patients were included if they were 18 years or older, presented within 4.5 hours with mild or minor stroke symptoms (NIHSS 0-5), AIS was confirmed by imaging, and patients received IVT therapy. Patients were divided based on their initial NIHSS into 
either NIHSS 3-5 or NIHSS 0-2 groups and were evaluated with a predetermined 2:1 ratio, due to fewer anticipated patients in the NIHSS 0-2 group. The primary 
endpoint was modified Rankin Scale (mRS) score of 0-1 at 90 days. Secondary endpoints include mortality at 90 days, in-hospital death, recurrent stroke, 
symptomatic intracranial hemorrhage, hemorrhagic transformation, early neurological deterioration, early neurological improvement, NIHSS 0 at discharge, mRS at 90 days, and time to IVT administration. 


Results: A total of 58 patients were included in this study, with 40 patients in the NIHSS 3-5 group and 18 patients in the NIHSS 0-2 group. 11 patients in the 0-2 group and 29 patients in the 3-5 group achieved mRS of 0-1 at 90 days. Overall, compared to patients in the NIHSS 0-2 group, the patients in the 3-5 group did not have a higher odd of having mrs 0-1 at 90 days, as shown by an adjusted odd ratio of 1.75, 95% confident interval of 0.52-5.79, and a p value of 0.4. No deaths were observed during hospital stay and at 90 days. Hemorrhagic conversion occurred in 5 (13%) of patients in the NIHSS 3-5 group and in 1 (5.6%) of patients in the NIHSS 0-2 group. Recurrent stroke occurred in 5 (13%) of patients in the NIHSS 3-5 group and did not occur in the NIHSS 0-2 group. Median time to IVT administration was 39 minutes in the NIHSS 3-5 group and 51 minutes in the NIHSS 0-2 group.

Conclusion: Among patients with NIHSS 0-5 treated with IVT therapy, there were no differences in functional outcome at 90 days between the NIHSS 3-5 group and the NIHSS 0-2 group. No meaningful differences in secondary outcomes were observed. In conclusion, further studies with a larger sample size are still needed to support an informed decision to administer IVT therapy in this patient population.