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Acute Stanford type A aortic dissection (ATAAD) with sudden onset and high mortality requiries a standard Bentall operation and a accurate prognosis in common, together with alteration of CO2 combining power (CO2CP) and serum sodium rase concern, hence, we evaluated the prognostic value of CO2CP combined with serum sodium in ATAAD patients. This retrospective study included 183 patients who underwent Bentall operation for ATAAD from 2015 to 2021 in the Fourth Hospital of Hebei Medical University, subsequently followed grouping by the levels of CO2CP and serum sodium. The study endpoint was 30-day all-cause mortality, and the prognostic value of CO2CP combined with serum sodium levels in ATAAD patients were evaluated with multivariate logistic regression method. The postoperative incidence of in-hospital death and adverse events in patients with ATAAD were 18% and 25.7%, respectively. Combination of CO2CP and serum sodium for predicting ATAAD death and adverse events presented a higher predictive value than each single indicator with ROC curve analysis (the AUC of CO2CP combined with serum sodium was 0.786, 95% CI 0.706–0.869, P < 0.001), along with CO2CP < 22.5 mmol/L + serum sodium > 138.5 mmol/L group had the worst prognostic. Multivariate regression analyse showed that CO2CP < 22.5 mmol/L combined with serum sodium > 138.5 mmol/L preferably predicted the prognosis of ATAAD (OR =6.073, 95% CI 2.557–14.425, P < 0.001). Consistently, the cumulative 30-day survival after surgery in ATAAD patients with the low CO2CP and high serum sodium simultaneously was the worst (log-rank P < 0.05). The combination of CO2CP and serum sodium increases the predictive value of prognosis, which is conducive to risk stratification of patients with ATAAD. [ABSTRACT FROM AUTHOR]

Accurate electromagnetic (EM) modeling for packaging structures with lossy interconnects requires to consider the finite conductivity of the conducting interconnects. In the integral equation approach, the conducting loss is usually accounted for through an approximate surface impedance when the skin depth of current is small, but this approximation may not be valid for large skin depth caused by low frequencies or small conductivities. In this paper, we treat the lossy interconnects as dielectric-like media and use the two-region electric field integral equations (EFIEs) to characterize the EM feature of the interconnects. The EFIEs are solved with the method of moments in which the Rao–Wilton–Glisson (RWG) basis function and dual basis function (DBF) are used to represent the electric and magnetic current densities, respectively. The joint use of RWG and DBF can remove the need of wisely formulating integral equations and selecting testing schemes and also alleviate the low-frequency effect in a wideband modeling for multiscale interconnect structures. Numerical examples are presented to demonstrate the approach and its robustness has been verified. [ABSTRACT FROM PUBLISHER]