Abstract P179: Impact of Transportation Mode on Outcome of Mechanical Thrombectomy

Abstract

Introduction: It is well established that mechanical thrombectomy (MT) improves functional outcome in stroke patients with a large vessel occlusion and salvageable brain tissue. In this study, we evaluate the impact of transportation mode on outcomes of patients undergoing MT. Methods: The prospectively maintained data from medical charts of consecutive patients transferred to a single comprehensive stroke center (CSC) for thrombectomy from January 2017 to December 2019 was reviewed. Clinical outcome was measured at a 90-day follow up with National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). Multivariate logistic regression analysis was used to assess the relationship between helicopter transportation and favorable 90-day outcome in MT patients. Results: A total of 135 MT patients underwent the procedure following interhospital transfer by helicopter or ground ambulance. 60/135 (44%) of the patients were transferred by air. On univariate analysis there was no significant differences in age (median of 66 vs. 68 years; p=0.23), sex (31% vs. 36% men; p=0.605) or race (31% vs. 44% white; p=0.344) between the air vs. ground groups. Also, baseline NIHSS did not differ (95% CI 12.0-15.69 vs. 14.06-17.31; p=0.136). Total of 56 (41.5%) patients received tissue plasminogen activator (tPA) (25 air vs. 31 ground; p=0.97) and the overall door to groin time was similar in both groups (85.17 vs. 83.96 minutes; p=0.86). NIHSS at 90-day follow up was significantly lower in those taken by helicopter compared to ground transit (95% CI 4.60-11.26 vs. 11.50-17.61; p=0.015). Air transportation was independently associated with good long-term functional outcome on multivariable logistic regression after controlling for age, sex, race, tPA and transportation time (OR 3.757 95% CI 1.23-11.4; p=0.02). Conclusions: Air transportation in MT patients was independently associated with better long-term functional outcome. The association between helicopter transit and long-term function is shown to be independent of transit time.