Is day surgery safe? A Danish multicentre study of morbidity after 57,709 day surgery procedures

Background Day surgery is expanding in several countries, and it is important to collect information about quality. The aim of this study was to assess morbidity and unanticipated hospital visits 0–30 days post-operatively in a large cohort. Methods We prospectively recorded data from 57,709 day surgery procedures performed in eight day surgery centres over a 3-year period. We cross-checked with the National Patient Registry to identify complications 0–30 days post-operatively, and registrations from The Danish Register of Cause of Death were requested. We retrieved the records of 1174 patients to assign a relation between secondary contact and day surgery. Results The overall rate of return hospital visits was 1.21% [95% confidence interval (CI): 1.12–1.30%] caused by a wide range of diagnoses. No deaths were definitely related to day surgery. The return hospital visits were due to haemorrhage/haematoma 0.50% (95% CI: 0.44–0.56%), infection 0.44% (95% CI: 0.38–0 49%) and thromboembolic events 0.03%. Major morbidity was rare. The surgical procedures with the highest rate of complication were tonsillectomies 11.4%, surgically induced abortions 3.13% and inguinal hernia repairs 1.23%. Conclusion This large-scale Danish national study confirmed that day surgery is associated with a very low rate of return hospital visits. Despite the rapid expansion of day surgery, safety has been maintained, major morbidity being very rare, and no deaths being definitely related to day surgery.