Risk rtPA: An iOS mobile application based on TURN for predicting 90-day outcome after IV thrombolysis

Objective: We recently developed Thrombolysis risk Using mRS and NIHSS (TURN), a simple score using only prestroke mRS scores and admission NIHSS scores to predict 90-day outcome after IV thrombolysis in ischemic stroke patients. Our purpose was to develop and test a mobile application for utilization of TURN at the bedside.

Methods: We developed Risk rtPA, an iOS mobile application based on TURN for prediction of 90-day excellent and severe outcome after IV thrombolysis. Excellent outcome was defined as 90-day mRS≤1. Severe outcome was defined as 90-day mRS≥5. Predictors for excellent and severe outcome were calculated using the inverse logit of -TURN and TURN respectively. We retrospectively validated our mobile application using data from 303 patients who received IV rt-PA during the NINDS rt-PA trial. Sensitivity and specificity analyses were performed using receiver operating characteristic (ROC) curves.

Results: Prediction of excellent and severe outcome using Risk rtPA followed an S-shaped curve as expected. We confirmed this finding using data from the NINDS trial. Cutoffs selected after ROC analysis predicted severe outcome with sensitivity of 94.4% and specificity of 52.2%, and excellent outcome with specificity of 83.9% and sensitivity of 61.2%.

Conclusion: The Risk rtPA mobile application predicted 90-day excellent and severe outcome in most clinically relevant cases. This mobile application brings the TURN score to the bedside for prediction of 90-day outcome in ischemic stroke patients being evaluated for IV thrombolysis.