Abstract TMP42: 911 Continuation Of Care Protocol Reduces Door In, Door Out Time For Transfer Patients With Emergent Large Vessel Occlusion

Abstract

Background: Rapid reperfusion with mechanical thrombectomy (MT) for large vessel occlusion leads to an improvement functional independence. Prolonged transfers from non-interventional to interventional hospitals are a major cause of delay in reperfusion times. The use of the 911 EMS system has accelerated myocardial infarction transfers and potentially could accelerate stroke transfers, but their effect on stroke transfer times have not been well delineated. Methods: In our 14- hospital system, transfers from non-interventional facilities to intrasystem or intersystem interventional capable facilities typically utilize a centralized group of nurses who arrange for contracted ambulance pickup (CAP). However, in San Bernardino County (CA), 911 EMS continuation of care (COC) is an alternative method available for transferring MT patients. Under the COC process, the sending hospital calls 911 and the nearest EMS ambulance responds to transport the patient to the thrombectomy center. We compared Door In, Door Out (DIDO) times between the COC vs CAP protocol between January 1, 2021 and January 30, 2022. Demographic and clinical variables were compared using t-test for continuous variables and chi-square for categorical variables. Results: Among 112 patients, 26 (23%) were transferred by COC and 86 (77%) by CAP. COC and CAP patients did not significantly differ in age ( Mdn 71 {IQR:22} vs Mdn 72 {IQR:20.5}, p = 0.81), sex (46% vs 36% female, p = 0.92), or presenting NIHSS ( Mdn 14 {IQR:12} vs Mdn 13 {IQR:14}, p = 0.62). Rates of thrombolytic started at the sending hospital were 54% (14/26) in COC patients and 48% (41/86) in ETAP patients (p = 0.58). DIDO time was faster in the COC group, ( Mdn 58 minutes {IQR 44-73} vs Mdn 94 minutes {IQR 79-142}, p<0.01). In contrast, there was a significant difference in DIDO time between intrasystem transfers by COC ( Mdn 69.5 min. {IQR: 48.5-115.5} and transfers out of system by COC ( Mdn 66 min.{IQR: 53-88}, p=0.20), suggesting that there was no special advantage for intrasystem transfers over intersystem transfers. Conclusion: Using the 911 EMS system for interfacility transport of patients eligible for MT reduced DIDO time at the sending hospital by over 40 minutes, which may contribute to improved functional outcome.