Maximum IV-tPA Dose is Associated with Greater Likelihood of Hemorrhagic Conversion, and Worse Functional Outcome at Discharge
Introduction: IV-tPA is the mainstay of treatment for acute ischemic stroke (AIS) at a weight-based dose of 0.9 mg/kg with a maximum limit of 90 mg. The prevalence of adult obesity in the United States has progressively increased; hence, the percentage of patients receiving the maximum dose is expected to rise as well. We examined differences between AIS patients treated with the weight-based dose (WBD) vs. the maximum dose (MD) of IV-tPA.
Methods: We performed a historical cohort study using the Baptist Hospital Get With The Guidelines Stroke database between October 2013 and February 2017. Selection criteria included hospital admission, age > 18 years, received IV-tPA as treatment for their AIS and have a recorded measured or estimated weight. Patients were dichotomized into WBD group (<90 mg, 0.9mg/kg), weighing <100 kg, and MD group (90mg), weighing ≥ 100 kg. Categorical variables were summarized using count and percentages then analyzed using Chi square tests. Continuous variables were summarized using mean, range and standard deviation then analyzed using independent samples t-tests.
Results: In total, 328 patients were included in the study, 38 (11.6%) in the MD group. The proportions of younger, male, non-Hispanic, taking antidiabetic and anticholesterol drugs were higher in the MD group. There were no statistically significant differences for initial NIHSS and 90-day modified Ran-kin Scale (mRS) between groups. The proportion of patients with mRS (3 to 6) at discharge was higher in the MD group (82% vs. 77%; P<0.001). The frequency of symptomatic ICH was three times higher in the MD group (9.5 vs. 3.1%; P=0.045).
Conclusion: Patients who received MD IV t-PA for AIS were more likely to have ICH and a worse discharge functional outcome compared to the WBD group. This was not seen on the 90-day mRS, possibly explained by a 28% lost to follow-up rate.
14th Annual BHSF Research Conference
Starosciak, Amy, "Maximum IV-tPA Dose is Associated with Greater Likelihood of Hemorrhagic Conversion, and Worse Functional Outcome at Discharge" (2019). All Publications. 3307.