Transportation model for acute aortic dissection: implications for reduced treatment centres.

Abstract

The objective of the present study was to model the effects of a reduced number of treatment centres for acute type A aortic dissection on preclinical transportation distance and time. We examined whether treatment in selected centres in Germany would be implementable with respect to time to treatment. For our transportation model, the number of aortic dissections and respective mean annual volume were collected from the annual quality reports (2015-2017) of all German cardiac surgery centres (n = 76). For each German postal code, the fastest and shortest routes to the nearest centre were calculated using Google Maps. Furthermore, we analysed data from the German Federal Statistical Office from January 2005 to December 2015 to identify all surgically treated patients with acute type A aortic dissection (n = 14102) and examined the relationship between in-hospital mortality and mean annual volume of medical centres. Our simulation showed a median transportation distance of 27.13 km and transportation time of 35.78 min for 76 centres. Doubling the transportation time (70 min) would allow providing appropriate care with only 12 medical centres. Therefore, a mean annual volume of >25 should be obtained. High mean annual volume was associated with significantly lower in-hospital mortality rates (P < 0.001). A significantly lower mortality rate of 14% was observed (P < 0.001) if a mean annual volume of 30 was achieved. Operationalizing the volume-outcome relationship with fewer but larger medical centres results in lower mortality, which outweighs the disadvantage of longer transportation time.