This study aimed to evaluate the impact of cardiopulmonary bypass for thoraco-abdominal normothermic regional perfusion on the metabolic milieu of donation after cardiac death organ donors before transplantation.Local donation after cardiac death donor offers are assessed for suitability and willingness to participate. Withdrawal of life-sustaining therapy is performed in the operating room. After declaration of circulatory death and a 5-minute observation period, the cardiac team performs a median sternotomy, ligation of the aortic arch vessels, and initiation of thoraco-abdominal normothermic regional perfusion via central cardiopulmonary bypass at 37 °C. Three sodium chloride zero balance ultrafiltration bags containing 50 mEq sodium bicarbonate and 0.5 g calcium carbonate are infused. Arterial blood gas measurements are obtained every 15 minutes after every zero balance ultrafiltration bag is infused, and blood is transfused as needed to maintain hemoglobin greater than 8 mg/dL. Cardiopulmonary bypass is weaned with concurrent hemodynamic and transesophageal echocardiogram evaluation of the donor heart. The remainder of the procurement, including the abdominal organs, proceeds in a similar controlled fashion as is performed for a standard donation after brain death donor.Between January 2020 and May 2022, 18 donation after cardiac death transplants using the thoraco-abdominal normothermic regional perfusion protocol were performed at our institution. The median donor age was 42.5 years (range, 20-51 years), and 88.9% (16/18) were male. The mean total donor cardiopulmonary bypass time was 88.8 ± 51.8 minutes. At the beginning of cardiopulmonary bypass, the average donor lactate was 9.4 ± 1.5 mmol/L compared with an average final lactate of 5.3 ± 2.7 mmol/L (P<.0001). The average beginning potassium was 6.5 ± 1.8 mmol/L compared with an average end potassium of 4.2 ± 0.4 mmol/L (P<.0001) . The average beginning hemoglobin was 6.8 ± 0.7 g/dL, and the average end hemoglobin was 8.2 ± 1.3 g/dL (P<.001) . On average, donation after cardiac death donors received transfusions of 2.3 ± 1.5 units of packed red blood cells. Of the 18 donors who underwent normothermic regional perfusion, all hearts were deemed suitable for recovery and successfully transplanted, a yield of 100%. Other organs successfully recovered and transplanted include kidneys (80.6% yield), livers (66.7% yield), and bilateral lungs (27.8% yield).The use of cardiopulmonary bypass for thoraco-abdominal normothermic regional perfusion is a burgeoning option for improving the quality of organs from donation after cardiac death donors. Meticulous intraoperative management of donation after cardiac death donors with a specific focus on improving their metabolic milieu may lead to improved graft function in transplant recipients.
This paper treats the automatic translation of register transfer level (RTL) descriptions of digital systems to VLSI realization. The target technology is the storage logic array or SLA. The approach is aimed at applications where the emphasis is on reducing engineering effort and design turnaround time rather than maximizing chip area utilization. The paper develops a mapping between the register transfer language, AHPL, and the SLA. It is shown that each primitive explicitly appearing in an AHPL description can be mapped into an area of real estate in an SLA realization. A detailed development of some of the algorithms is presented. The entire process has been successfully implemented and applied to a set of examples. This is accomplished by developing a final stage for an already existing three-stage multi-application compiler for AHPL. Layout and routing are shown to be a single optimization process if the hardware target is an SLA.
A novel technique for synchronous fault simulation of sequential circuits utilizing surrogate fault propagation and backward fault collection is introduced, and its implementation is evaluated. Fault effects which reconverge over time are simulated as exceptions. Evidence which shows SFSSE (synchronous fault simulation by surrogate with exceptions) to be superior to existing approaches is presented. As in deductive and concurrent simulation, execution time drops dramatically as the majority of faults are detected. SFSSE incorporates features of both deductive and parallel fault simulations while avoiding the drawbacks of each of these techniques. In contrast to deductive simulation, fault lists are processed only at primary outputs and memory elements. This is critical with respect to both execution time and storage requirements.< >
Digital hardware synthesis implies the use of clock mode register transfer level descriptions. A major feature of this approach to synthesis is the possibility of integrating test generation into the design and synthesis process. Preliminary synthesis makes it possible to link test search at the function level to fault enumeration at the network level. A recently developed backward state justification search has eliminated the final bottleneck in automatic test generation.< >
A CONLAN document has significance only if it is read by a person or machine. That reader (environment) is required to use available facilities to respond to and interact with the document. It must provide the type checking mechanism. It must record the names of defined and declared items and provide the data base they require. It must record signal values. From such records, it can determine facts of importance to continued document evaluation. "System interfaces" are prescribed environment responses, not formally defined via CONLAN syntax.
The development of a CONLAN(CONsensus LANguage) goes back to the first Symposium on Hardware Description Languages (HDL) at Rutgers University in 1973. It was initiated by J. Lipovski, then Univ. of Florida. After two years of preparatory work the CONLAN Working Group was formed on the occasion of the third Symposium on HDL in New York. These papers represent the result of four years of hard work of a group spread out over two continents. This work is by no means complete; many things have still to be done. Nevertheless, encouraged by the positive response to an informal presentation of our approach at the fourth Symposium on HDL in Palo Alto 1979, we feel that publication of what we have obtained so far is warranted. This paper presents the basic principles of CONLAN. Two companion papers [1, 2] treat language derivation and language application within the framework of CONLAN. A more detailed report, of which a draft exists already, will be forthcoming soon.
Techniques for selecting optimum sensitization paths in a logic circuit and for reducing backtrackings using a heuristic function in the form of a work load are described. The test generation algorithm, which has some resemblance to PODEM, reduces the number of backtrackings by early detection of conflicts in assignments of line values. The techniques described have deeper look-ahead capabilities than other algorithms and reduce the length of the backward consistency drive using the concepts of free and biased lines. Critical to the method is a nine-value, single-fault calculus, constituting a superset of the five values used in the classic D-algorithm. The premise of the five-value D-algorithm is that reconvergent fanout mandates a search over all subnetworks forward from the fault point. In contrast, if there exists a test that includes a single path, sensitized in terms of the nine-value calculus to a network output, this test will be justified by the backward consistency drive.< >
CONLAN is a formal semantic and syntactic base for the description of all phases in the design and documentation of digital systems. Previous papers[1, 2] have presented the basic concepts and models underlying the whole CONLAN language family. On the example of the construction of Base CONLAN, the first level which can be of some operational interest to the hardware designer, it has been shown how a coherent set of special purpose application languages can be derived from a common mathematical base, Primitive Set CONLAN.
