Functional outcomes of pre-hospital thrombolysis in a mobile stroke treatment unit compared with conventional care: an observational registry study

Background Specialised CT-equipped mobile stroke treatment units shorten time to intravenous thrombolysis in acute ischaemic stroke by starting treatment before hospital admission; however, direct effects of pre-hospital thrombolysis on clinical outcomes have not been shown. We aimed to compare 3-month functional outcomes after intravenous thrombolysis in patients with acute ischaemic who had received emergency mobile care or and conventional care. Methods In this observational registry study, patients with ischaemic stroke received intravenous thrombolysis (alteplase) either within a stroke emergency mobile (STEMO) vehicle (pre-hospital care covering 1.3 million inhabitants of Berlin) or within conventional care (normal ambulances and in-hospital care at the Charite Campus Benjamin Franklin in Berlin). Patient data on treatment, outcome, and demographics were documented in STEMO (pre-hospital) or conventional care (in-hospital) registries. The primary outcome was the proportion of patients who had lived at home without assistance before stroke and had a 3-month modified Rankin Scale (mRS) score of 1 or lower. Our multivariable logistic regression was adjusted for demographics, comorbidities, and stroke severity. This study is registered with ClinicalTrials.gov, number NCT02358772. Findings Between Feb 5, 2011, and March 5, 2015, 427 patients were treated within the STEMO vehicle and their data were entered into a pre-hospital registry. 505 patients received conventional care and their data were entered into an in-hospital thrombolysis registry. Of these, 305 patients in the STEMO group and 353 in the conventional care group met inclusion criteria and were included in the analysis. 161 (53%) patients in the STEMO group versus 166 (47%) in the conventional care group had an mRS score of 1 or lower (p=0.14). Compared with conventional care, adjusted odds ratios (ORs) for STEMO care for the primary outcome (OR 1.40, 95% CI 1.00-1.97; p=0.052) were not significant. Intracranial haemorrhage (p=0.27) and 7-day mortality (p=0.23) did not differ significantly between treatment groups. Interpretation We found no significant difference between the proportion of patients with a mRS score of 1 or lower receiving STEMO care compared with conventional care. However, our results suggest that pre-hospital start of intravenous thrombolysis might lead to improved functional outcome in patients. This evidence requires substantiation in future large-scale trials.