ObjectiveEnhanced recovery after surgery (ERAS) is a protocol of evidence based practices applied in major surgery. Open aortic aneurysm repair is major surgery in terms of complications and mortality. This study aimed to compare early outcomes of ERAS with a traditional post-operative protocol in patients undergoing elective open aortic surgery. MethodsThis retrospective cohort study was conducted between 2018 – 2022 in two tertiary vascular surgery centres. The ERAS program was routinely implemented in one centre, while the other one used a standard peri-operative protocol. The primary outcome was post-operative length of stay (pLOS). Secondary outcomes were 30 day mortality, complications, re-interventions, and rehospitalisations. Propensity score weighting was used to balance the two groups by comorbidities. Inverse probability of treatment weight (IPTW) was used to estimate the average treatment effect on the treated patients. ResultsA total of 198 patients were enrolled: 128 in the ERAS group (EG) and 70 in the standard group (SG). Mean age was 70.8 ± 6.7 years in EG and 71.1 ± 6.7 in SG (p = .34). No significant differences were observed in pre-operative cardiovascular risk factors. Median pLOS was 5 days (IQR 3, 6) in the EG group and 8 days (IQR 6, 11) in the SG group (p < .001). No differences in terms of mortality, re-operations, and rehospitalisations were observed. The IPTW analyses showed a 40% reduction in pLOS and a significant reduction in major complications in EG (OR 0.41, 95% CI 0.26 – 0.66; p < .001). A 45% increase in pLOS in patients with chronic obstructive pulmonary disease was found in both groups. ConclusionEnhanced recovery after surgery is safe and feasible for elective open aortic surgery, and associated with earlier hospital discharge without differences in terms of mortality and lower complication rates compared with a standard protocol. Chronic obstructive pulmonary disease is a major risk factor for an increase in pLOS. The ERAS protocol is promising in terms of resource utilisation.