Abstract WMP79: Recapitulation on the Ground of Helicopter Flight Low Frequency Vibration Enhances Stroke Thrombolysis
Background: Understanding the potential effects on stroke outcome of the unique physical factors present in a helicopter ambulance flight is critical in the era of thrombectomy. However, this factor in patient care has not been adequately investigated. Methods: This was a prospective randomized blinded end-point animal study. A murine model of middle cerebral artery autologous thromboembolic occlusion (eMCAO) with rtPA reperfusion was exposed to three different settings: 1) a standardized actual helicopter flight, 2) a motion platform simulator that delivered the exact LFV signature of the helicopter, and 3) a ground control. Outcome measures included infarct size and BBB permeability on MRI, and neurological scores. Results: A total of 106 mice were analyzed. Within the rtPA group, LFV simulator mice displayed lower infarction volumes on MRI (31.6 vs. 54.9 mm 3 , p=0.007) and improved neurological scores (87 vs. 28%, p=0.0001) compared to ground control mice. By contrast, mice receiving saline did not show change in either infarction volume (80.9 vs. 95.3, p=0.8) or neurological scores (37 vs. 28%, p=0.7). No differences were seen in the actual helicopter flight group as compared with ground control. No treatment group showed any difference in permeability of the blood brain barrier, assessed by MRI. Conclusion: We found a synergistic beneficial effect of combining helicopter-like LFV and rtPA, which could provide a novel, safe, and potentially more efficacious intervention for patients with stroke. These results also suggest that non-LFV helicopter physical factors, such, as hypobaric environment, accelerations and noise, may have a negating effect on the otherwise positive effect of helicopter vibration on stroke outcomes. If so, strategies to minimize these negating factors might be expected to improve patient outcome.