Hospital economic impact from hemostatic matrix usage in cardiac surgery

Objective:

Improved health outcomes can result in economic savings for hospitals and payers. While effectiveness of topical hemostatic agents in cardiac surgery has been demonstrated, evaluations of their economic benefit are limited. This study quantifies the cost consequences to hospitals, based on clinical outcomes, from using a flowable hemostatic matrix vs non-flowable topical hemostatic agents in cardiac surgery.

Research design and methods:

Applying clinical outcomes from a prospective randomized clinical trial, a cost consequence framework was utilized to model the economic impact of comparator groups. From that study, clinical outcomes were obtained and analyzed for a flowable hemostatic matrix (FLOSEAL, Baxter Healthcare Corporation) vs non-flowable topical hemostats (SURGICEL Nu-Knit, Ethicon–Johnson &; Johnson; GELFOAM, Pfizer). Costing analyses focused on the following outcomes: complications, blood transfusions, surgical revisions, and operating room (OR) time. Cardiac surgery costs were analyzed and expressed in 2012 US dollars based on available literature searches and US data. Comparator group variability in cost consequences (i.e., cost savings) was calculated based on annualized impact and scenario testing.

Results:

Results suggest that if a flowable hemostatic matrix (rather than a non-flowable hemostat) was utilized exclusively in 600 mixed cardiac surgeries annually, a hospital could improve patient outcomes by a reduction of 33 major complications, 76 minor complications, 54 surgical revisions, 194 transfusions, and 242?h of OR time. These outcomes correspond to a net annualized cost consequence savings of $5.38 million, with complication avoidance as the largest contributor.

Conclusions:

This cost consequence framework and supportive modeling was used to evaluate the hospital economic impact of outcomes resulting from the usage of various hemostatic agents. These analyses support that cost savings can be achieved from routine use of a flowable hemostatic matrix, rather than a non-flowable topical hemostat, in cardiac surgery.     

Testing for unit roots in time series models with non-stationary volatility

Many of the key macro-economic and financial variables in developed economies are characterized by permanent volatility shifts. It is known that conventional unit root tests are potentially unreliable in the presence of such behaviour, depending on a particular function (the variance profile) of the underlying volatility process. Somewhat surprisingly then, very little work has been undertaken to develop unit root tests which are robust to the presence of permanent volatility shifts. In this paper we fill this gap in the literature by proposing tests which are valid in the presence of a quite general class of permanent variance changes which includes single and multiple (abrupt and smooth-transition) volatility change processes as special cases. Our solution uses numerical methods to simulate the asymptotic null distribution of the statistics based on a consistent estimate of the variance profile which we also develop. The practitioner is not required to specify a parametric model for volatility. An empirical illustration using producer price inflation series from the Stock–Watson database is reported.     

Monetary Policy in Austria–Hungary, 1876–1913: An Econometric Analysis of the Determinants of the Central Bank’s Discount Rate and the Liquidity Ratio

This paper presents a model to explain the official discount rate of the Central Bank of Austria–Hungary from 1876 to 1913. The discount rate is assumed to depend on the liquidity ratio of the Bank, defined as the ratio of its stock of metals to banknotes issued, and on changes in foreign discount rates. The paper also presents an equation explaining the liquidity ratio. We use “not equally spaced chronologically ordered data” referring to the 50 discount rate changes enacted. The regressions confirm that the liquidity ratio was the main determinant of the discount rate and that Germany (and not Great Britain) played a significant role in determining the Austro–Hungarian discount rate and the liquidity ratios, supporting the view that the classical gold standard was a decentralized multipolar system rather than a system fully dominated by London as suggested by Keynes. The regressions also suggest that, although Austria–Hungary had an inconvertible paper currency (1879–1892) and fluctuating exchange rates (1876–1895) and formally joined the gold standard only in 1902, it “shadowed” the behaviour of gold standard Central Banks with such consistency that the stability of the estimated regressions was relatively unaffected by the frequent institutional changes.