Subcostal bilateral internal thoracic artery harvesting with the da Vinci Single Port system: an experimental feasibility study.

We evaluated the feasibility of harvesting bilateral internal thoracic arteries with the da Vinci Single Port system (SP) through a single left-sided subcostal incision. Complete bilateral mobilization with sufficiently long conduits for multivessel grafting was possible in 2 human cadavers and 2 live porcine. Creating the subcostal access and docking the SP system took between 14 and 21 min and the total harvest time ranged from 65 to 125 min in all models. No major bleeding was observed in the live porcine and hemostasis was managed with the available instrumentation. One porcine deceased during surgery due to ventricular fibrillation followed by cardiac arrest. The robotic harvesting was technically easily reproduced by the surgeons and required no additional rib-spreading. Further studies will be required to assess if this subcostal approach with the da Vinci SP system yields true clinical benefits in patients.

Monolithic Teflon membrane valves and pumps for harsh chemical and low-temperature use.

Microfluidic diaphragm valves and pumps capable of surviving conditions required for unmanned spaceflight applications have been developed. The Pasteur payload of the European ExoMars Rover is expected to experience temperatures ranging between -100 degrees C and +50 degrees C during its transit to Mars and on the Martian surface. As such, the Urey instrument package, which contains at its core a lab-on-a-chip capillary electrophoresis analysis system first demonstrated by Mathies et al., requires valving and pumping systems that are robust under these conditions before and after exposure to liquid samples, which are to be analyzed for chemical signatures of past or present living processes. The microfluidic system developed to meet this requirement uses membranes consisting of Teflon and Teflon AF as a deformable material in the valve seat region between etched Borofloat glass wafers. Pneumatic pressure and vacuum, delivered via off-chip solenoid valves, are used to actuate individual on-chip valves. Valve sealing properties of Teflon diaphragm valves, as well as pumping properties from collections of valves, are characterized. Secondary processing for embossing the membrane against the valve seats after fabrication is performed to optimize single valve sealing characteristics. A variety of different material solutions are found to produce robust devices. The optimal valve system utilizes a membrane of mechanically cut Teflon sandwiched between two thin spun films of Teflon AF-1600 as a composite "laminated" diaphragm. Pump rates up to 1600 nL s(-1) are achieved with pumps of this kind. These high pumping rates are possible because of the very fast response of the membranes to applied pressure, enabling extremely fast pump cycling with relatively small liquid volumes, compared to analogous diaphragm pumps. The developed technologies are robust over extremes of temperature cycling and are applicable in a wide range of chemical environments.

Totally endoscopic multivessel coronary artery bypass surgery using the da Vinci surgical system: a feasibility study on cadaveric models.

BACKGROUND: The aim of the study was to develop a totally endoscopic coronary artery bypass procedure for the treatment of multivessel disease (MVTECAB). METHODS: Procedure development was conducted on 6 human cadavers with the da Vinci Surgical System. For aortic clamping, a transthoracic aortic clamp was applied. The proximal anastomoses of vein grafts were created transthoracically with the Corlink automated anastomosis device. The target vessels on the heart were exposed with a modified endoscopically applicable Starfish vacuum device. In 1 cadaver, the endo-sling and endoscopic fan retractors were studied for exposure support. RESULTS: Harvesting of bilateral internal thoracic arteries was easily accomplished. Aortic clamping was easier from the right side. In the left-side approach, the proximal anastomoses were completed without leakage in all 3 cadavers. One incorrect deployment occurred, and the deployment needed to be redone. In the right-si d e approach, 1 proximal anastomosis was performed without leakage, and another needed to be repaired for incorrect deployment. The fan retractors either covered too much of the targeted area of the heart surface or did not provide good manipulation capabilities. The endo-sling enabled atraumatic exposure of the target vessels. The modified Starfish performed sufficiently for exposing target vessels. Problems were found with epicardial fat clogging the Starfish suction chamber and with bending of the suction tube neck, both of which resulted in a loss of tissue contact. Two of the cadavers approached from the left side were completely revascularized with 3 grafts, and 4 anastomoses were performed on the third cadaver. Triple-vessel revascularization was performed in the cadavers approached from the right side. CONCLUSION: This study demonstrates the feasibility of performing an MVTECAB on the arrested heart with the da Vinci Surgical System. Further procedure development is necessary to optimize the synergistic effects of the technologies used and to introduce this operation into clinical practice.