Characteristics and outcomes of older patients undergoing out- versus inpatient surgery in Europe. A secondary analysis of the Peri-interventional Outcome Study in the Elderly (POSE)

Background: The number of older patients undergoing surgical procedures with anaesthesia care is projected to rise. In order to cope with the increased demand, the expansion of outpatient surgery may play a decisive role. We aim to investigate the characteristics and outcomes of the older outpatient population. Patients and Methods: The Peri-interventional Outcome Study in the Elderly in Europe (POSE) was a prospective multicenter study investigating characteristics and outcomes in 9497 patients aged 80 years and older undergoing a procedure with anaesthesia care. This secondary analysis of the POSE data investigated characteristics, functional and cognitive outcomes, and mortality in the outpatient in comparison to the inpatient population. Functional status was assessed as independent, partially dependent, and totally dependent at baseline and 30 days postinterventional. Cognitive status was defined by the number of recalled words (0–3) in the Mini-Cog test and brief cognitive screening at baseline and follow-up. Results: Out of the 9497 older patients, 7562 were planned inpatients and 1935 planned outpatients. Older outpatients presented with fewer comorbidities and fewer medications than older inpatients and underwent minor procedures more often Their baseline functional status was more often independent, and they had a higher estimated probability of staying independent. Outpatients recalled three words at baseline and follow-up more often than inpatients. The estimated 30-day survival probabilities with 95% confidence intervals were 0.997 [0.994; 0.999] in the group with planned outpatient surgery and 0.948 [0.942; 0.953] with planned inpatient surgery. Conclusion: Our results indicate that functional and cognitive status at baseline and follow-up were higher in planned outpatients than in planned inpatients. However, only short screening tools for the assessment of functional and cognitive status were used. Overall, outpatient interventions were associated with low mortality. Further research is recommended to develop scores that facilitate the identification of patients suitable for outpatient surgery. Editorial Comment: This secondary analysis of a prospectively collected cohort of elderly surgical cases in Europe describes case factors related to inpatient compared to outpatient surgical interventions. The findings show that inpatient or outpatient surgery selection is associated with different degrees of risk for important perioperative outcomes in this cohort.