Socioenvironmental criteria and postoperative complications in ambulatory surgery in a French university hospital: a prospective cross-sectional observational study.

BACKGROUND Ambulatory surgery lowers hospitalisation costs, shortens the time to return to work but requires caution regarding socioenvironmental risk factors for complications and rehospitalisation. METHODS This was a single-centre prospective cross-sectional observational study conducted in a university hospital centrein January 2017. The primary objective was to assess the rate of conversion from ambulatory surgery to conventional hospitalisation or emergency department visit within 30 days following discharge from ambulatory unit. Secondary objectives were to describe the socioenvironmental characteristics of outpatients and to identify risk factors for severe postoperative complications. RESULTS 598 outpatients were included. The most represented surgical specialties were ophthalmology (23.5%), gynaecology (19%) and orthopaedics (17.7%). Patients' mean age was 50.8 years (SD, 19.8) and the male/female sex ratio was 0.68. There were 22 (3.68%, 95% CI 2.32% to 5.52%) severe complications, including 11 (1.84%, 95% CI 0.92% to 3.27%) conversions to conventional hospitalisation and 11 (1.84%) conversions to emergency department visit, 3 of which led to readmission. Regarding socioenvironmental characteristics, 116 outpatients (19.7%) lived alone but were not isolated and 15 (2.6%) lived alone and were socially isolated. Following ambulatory surgery, 9 outpatients (1.6%) returned home on foot, 20 (3.4%) by public transportation and 8 (1.4%) drove home; 133 outpatients (13.7%) were alone the first night following surgery. Severe complication rates were not significantly different according to socioenvironmental subgroups. CONCLUSION In our study, the prevalence of severe complications was low, conforming to the literature. The study was underpowered to estimate the effect of socioenvironmental variables.