Medicine and Health Sciences Commons^™

Blood-Brain Barrier Opening In A Large Animal Model Using Closed-Loop Microbubble Cavitation-Based Feedback Control Of Focused Ultrasound Sonication, Chih-Yen Chien, Lu Xu, Christopher Pham Pacia, Yimei Yue, Hong Chen

2020-Current year OA Pubs

Focused ultrasound (FUS) in combination with microbubbles has been established as a promising technique for noninvasive and localized Blood-brain barrier (BBB) opening. Real-time passive cavitation detection (PCD)-based feedback control of the FUS sonication is critical to ensure effective BBB opening without causing hemorrhage. This study evaluated the performance of a closed-loop feedback controller in a porcine model. Calibration of the baseline cavitation level was performed for each targeted brain location by a FUS sonication in the presence of intravenously injected microbubbles at a low acoustic pressure without inducing BBB opening. The target cavitation level (TCL) was defined for each target …

Wireless Implantable Optical Probe For Continuous Monitoring Of Oxygen Saturation In Flaps And Organ Grafts, Hexia Guo, Yameng Xu, Lauren Jacobson, Amanda M Westman, Matthew R Macewan, Mitchell A Pet, Et Al.

2020-Current year OA Pubs

Continuous, real-time monitoring of perfusion after microsurgical free tissue transfer or solid organ allotransplantation procedures can facilitate early diagnosis of and intervention for anastomotic thrombosis. Current technologies including Doppler systems, cutaneous O

Pacing Therapy For Atrioventricular Dromotropathy: A Combined Computational-Experimental-Clinical Study, Floor C W M Salden, Peter R Huntjens, Et Al.

2020-Current year OA Pubs

AIMS: Investigate haemodynamic effects, and their mechanisms, of restoring atrioventricular (AV)-coupling using pacemaker therapy in normal and failing hearts in a combined computational-experimental-clinical study.

METHODS AND RESULTS: Computer simulations were performed in the CircAdapt model of the normal and failing human heart and circulation. Experiments were performed in a porcine model of AV dromotropathy. In a proof-of-principle clinical study, left ventricular (LV) pressure and volume were measured in 22 heart failure (HF) patients (LV ejection fraction <35%) with prolonged PR interval (>230 ms) and narrow or non-left bundle branch block QRS complex. Computer simulations and animal studies in normal hearts showed that restoring of AV-coupling …

Repeated Endo-Tracheal Tube Disconnection Generates Pulmonary Edema In A Model Of Volume Overload: An Experimental Study, Bhushan H Katira, Doreen Engelberts, Sheena Bouch, Jordan Fliss, Luca Bastia, Kohei Osada, Kim A Connelly, Marcelo B P Amato, Niall D Ferguson, Wolfgang M Kuebler, Brian P Kavanagh, Laurent J Brochard, Martin Post

2020-Current year OA Pubs

BACKGROUND: An abrupt lung deflation in rodents results in lung injury through vascular mechanisms. Ventilator disconnections during endo-tracheal suctioning in humans often cause cardio-respiratory instability. Whether repeated disconnections or lung deflations cause lung injury or oedema is not known and was tested here in a porcine large animal model.

METHODS: Yorkshire pigs (~ 12 weeks) were studied in three series. First, we compared PEEP abruptly deflated from 26 cmH

RESULTS: As compared to PEEP 5 cmH

CONCLUSION: Single abrupt deflation from high PEEP, and repeated short deflations from moderate PEEP cause pulmonary oedema, impaired oxygenation, and increased PVR, in this …

Hydraulic Permeability And Compressive Properties Of Porcine And Human Synovium, Milad Rohanifar, Benjamin B Johnston, Alexandra L Davis, Young Guang, Kayla Nommensen, James A J Fitzpatrick, Christine N Pham, Lori A Setton

2020-Current year OA Pubs

The synovium is a multilayer connective tissue separating the intra-articular spaces of the diarthrodial joint from the extra-synovial vascular and lymphatic supply. Synovium regulates drug transport into and out of the joint, yet its material properties remain poorly characterized. Here, we measured the compressive properties (aggregate modulus, Young's modulus, and Poisson's ratio) and hydraulic permeability of synovium with a combined experimental-computational approach. A compressive aggregate modulus and Young's modulus for the solid phase of synovium were quantified from linear regression of the equilibrium confined and unconfined compressive stress upon strain, respectively (H