Mortality and complications following visceral surgery—a nationwide analysis based on the diagnostic categories used in German hospital invoicing data

BACKGROUND: The in-hospital mortality after visceral surgery in Germany is unknown. METHODS: In this retrospective, descriptive analysis, nationwide hospital billing data based on diagnosis-related groups (DRG) over the period 2009-2015 were studied to determine the in-hospital mortality, complications and their management, and deaths after documented severe complications (failure to rescue, FTR) after visceral surgery in Germany. Organ-system subgroups were defined and subdivided into frequent operations (inguinal hernia repair, appendectomy, thyroid operations, cholecystec- tomy), colorectal operations, and complex operations (surgery of the esophagus, pancreas, liver, and stomach). RESULTS: 3 287 199 patients from 1392 hospitals were included in the analysis. The in-hospital mortality after visceral surgery was 1.9%. The lowest mortality was after the frequently performed operations (0.04-0.4%), the highest after complex surgery of the esophagus (8.6%) and stomach (11.7%). Severe complications were most commonly seen after complex surgery of the pan- creas (27.7%), liver (24.3%), esophagus (37.8%), and stomach (36.7%). 90.6% of deaths occurred after colorectal or complex operations, which together accounted for 23% of all operations. The FTR rate was 8.4% after appendectomy and cholecystec- tomy (95% confidence interval [8.34; 8.46]) and 20.3% after esophageal surgery ([19.8; 20.8]). CONCLUSION: In Germany, in-hospital mortality after visceral surgery is not uncommon, with a frequency of nearly 2%. Improved complication management after complex operations appears necessary. A limitation of this study is the identification of compli- cations from anonymized billing data.