Complications after thyroid gland operations in Germany. A routine data analysis of 66,902 AOK patients

Routine data from hospitals in the public healthcare system allow the analysis of large patient datasets without generating additional documentation efforts for hospitals. This study reports the frequencies of postoperative complications after thyroid surgery based on routine nationwide data. Moreover, volume-outcome relationships were investigated. Nationwide routine data from insured patients of the Local Health Insurance Fund (AOK) who underwent thyroid surgery between 2008 and 2010 were analyzed. Complications were determined based on indicators for permanent vocal cord palsy, re-bleeding with re-operations and wound infections with specific treatment. The effect of hospital volumes (volume quintiles) on the indicators was determined by multivariate logistic regression. A total of 66,902 thyroid gland operations were identified. The overall frequency of permanent vocal cord palsy was 1.5 %, re-bleeding 1.8 % and wound infections 0.4 %. In the four lowest case volume categories the risk of permanent vocal cord palsy was significantly higher compared to the highest case volume hospitals (odds ratio 1.5, 1.7, 1.7 and 2.2, respectively). This study represents the reality of healthcare for thyroid surgery in Germany. Additionally, it was determined that the risk for permanent vocal cord palsy after thyroid gland operations decreased with increasing case volumes of hospitals.