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Unilateral diaphragmatic paralysis in children with univentricular circulation poses significant challenges, including impaired hemodynamics and increased postoperative complications. Restoring diaphragmatic function is crucial to mitigate these risks. This study investigates the feasibility of automated stimulation of the paretic diaphragm half using electromyography (EMG) signals from the non-paretic side following transection of the right phrenic nerve. Our findings demonstrate successful automated stimulation, suggesting the potential development of an EMG-triggered synchronized unilateral diaphragmatic pacemaker. This innovative approach holds promise as a novel therapeutic intervention for managing unilateral diaphragmatic paralysis in pediatric patients with univentricular circulation.

Background: The intraoperative application of focused transthoracic echocardiography (TTE) is often considered to be restricted. Echocardiography with pocket-sized hand held ultrasound systems has been shown to be feasible in various settings.Objective: The aim of this study was to investigate the feasibility of the intraoperative application of pocket-sized echocardiography and the comparison of its imaging quality and diagnostic reliability and variability with a standard ultrasound system.Methods: After written informed consent, TTE was performed on 40 anaesthetised general, vascular, visceral, thoracic surgical and orthopaedic patients according to the FATE protocol: first, with a pocket-sized and second, with a high-end ultrasound system randomly by two anaesthetists. Imaging quality of four basic and three additional FATE views was rated on an established scale from 1 (impossible) to 5 (perfect). Successful TTE was defined, if one basic FATE views would be rated as grade 4 or 5 or alternatively two views as grade 3. Pathologic findings by both ultrasound devices were documented and imaging quality and pathologic findings were compared.Results: All 40 patients presented acceptable imaging quality, resulting in a success rate of 1.0 (97.5%-CI 0.91-1, p= 0.015). The individual imaging ratings of each view were significantly lower with the pocket-sized system, but still showed acceptable imaging quality. With the high-end device more pathologic findings were detected (107 vs. 87), but none of the relevant or severe pathologies were overseen with the hand-held device.Conclusion: The application of a pocket-sized echocardiography device for focused intraoperative TTE is feasible and can appropriate be used for the initial evaluation of relevant pathologies in the operating theatre. [ABSTRACT FROM AUTHOR]

We present an alternative linear programming formulation of the maximum concurrent flow problem (MCFP) termed the triples formulation. The standard formulations in the literature are the edge-path and node-edge formulations, which are known to be equivalent due to the Flow Decomposition Theorem. We present algorithms for deriving a triples solution from an edge-path solution and vice versa, and hence show that all three formulations are equivalent. Our new formulation leads to more compact linear programs than either the edge-path or node-path formulations. We show that the triples formulation often has half the number of rows and half the number of columns compared to the node-edge formulation. We report computational results comparing the solution times using the three formulations and the state-of-the-art linear programming solver CPLEX on a set of popular problem instances from the literature and a set of instances defined on random geometric graphs. The results indicate that the triples formulation can be solved more efficiently than the other two. We found that the CPLEX linear programming solvers solved 89% of the MCFP instances in our computational study faster with the triples formulation than it did with the other two formulations, typically two to four times faster than the node-edge formulation when available computer memory allowed both to be solved. The triples formulation appears to be particularly well suited for problem instances defined on dense graphs; on average, CPLEX solved these types of problems in our study 10 times faster with the triples formulation. © 2014 Wiley Periodicals, Inc. NETWORKS, Vol. 65(1), 68-87. 2015 [ABSTRACT FROM AUTHOR]