Discussion

Application of the established ERAS protocol was equally high in our cohort on weekdays and during the weekend with minor differences for three individual items only.

Despite the significant lower compliance with the ERAS pathway for the group operated on at the end of the week, the ERAS protocol was applied equally in the three perioperative periods. The small overall difference should be considered as clinically irrelevant because all patients had the same functional and clinical outcomes.

Evidences from several clinical medicine areas suggest that the day of the week on which medical care is provided may have a significant impact on health outcomes. Some articles have even described a ‘weekend effect’ which represents a worse outcome for patients admitted at weekends compared with weekdays in terms of mortality and length of hospital stay.4 ,17 ,18 Zare et al3 have found a higher 30 days mortality (deaths in hospital and after discharge) after non-emergency surgery on Fridays, compared with early weekdays in patients admitted to regular wards. One possible explanation could be the poorer quality of care on weekends due to reduced staffing in terms of number and experience, with less senior staff. Furthermore, in the study of Aylin et al,2 the overall risk of death within 30 days for patients undergoing elective surgery increased with the day of the week on which the procedure was performed. Compared with Monday, the adjusted odds of death for all elective surgical procedures were, respectively, 44% and 82% higher if the procedures were carried out on Friday or at the weekend. The reasons for this difference remain unknown, but it appears that serious complications are more likely to occur within the first 48 hours after an operation, and a failure to rescue the patient could be related to reduced and/or locum staffing (expressed as number and level of experience) and poorer availability of services over a weekend. In our experience, no clinically relevant difference was found. We attribute this to the fact that most of the nursing staff is dedicated staff, and many of our caregivers were in the department already through the process of ERAS implementation and consolidation. In order to ensure continuity of care over the weekend, senior and junior staff members are paired whenever possible, and likewise for medical and nursing staff. Furthermore, new collaborators receive formal teaching on ERAS on arrival and periodically, the junior medical and nursing staff are instructed by senior surgeons and the dedicated clinical ERAS nurse to update all caregivers on ERAS care during institutional staff meetings. Improved clinical outcomes require a possibly complete application of the ERAS protocol. In clinical practice, a threshold of at least 70% of overall compliance was found to be significant12 (own unpublished data). In this study, a similarly high level of healthcare was maintained independent of the day of the week as reflected by an overall compliance of 78% and 76%, respectively. Although this difference was statistically significant, it appears unlikely that a 2% gap would be of clinical relevance. Furthermore, no difference was detected when analysing ERAS compliance by perioperative phase. This finding is important when the postoperative phase coincides with the weekend for patients operated on Thursday or Friday, respectively. The smallest meaningful difference for ERAS compliance has not been identified yet. However, studies focusing on the correlation of compliance with clinical outcomes found clinically significant effects for differences in compliance of 10% or more.12 ,19 This is in accordance with our findings of similar clinical outcomes for the two comparative groups. A well standardised pathway (like ERAS) might help to cope with limited resources on weekends or in general. Not every individual item of the complex protocol might have the same importance.14 Subtle differences existed between the two comparative groups. These were nurse-related measures such as delayed urinary catheter removal and prolonged intravenous fluid administration that could be explained by reduced staffing on the weekend, but again absolute differences were marginal and had no effect on recovery and clinical outcomes.

The application of enhanced recovery protocols in colorectal surgery allows some significant reduction in postoperative complication rates, length of stay and costs. A successful collaboration between multidisciplinary team members on the ward is needed to achieve high compliance with ERAS items and thus support patient recovery after surgery.

Ihedioha et al6 have examined the impact of the day of surgery on short-term recovery after colorectal surgery. They observed a significantly longer length of stay in patients operated later on in the week. The results of their study differ from our present results, since we did not observe any difference in length of stay and complication rates between patients operated on Monday and Tuesday versus Thursday and Friday.

This is a retrospective study with inherent limitations and sources of bias. However, selection bias appears unlikely because OR scheduling was based on logistic and administrative reasons only. Furthermore, all consecutive patients were included in this study and data were retrieved from a dedicated, prospectively maintained database. The cohort is heterogeneous (colon and rectal resections) and the study might be underpowered to detect small differences of certain end points (eg, complications) between the comparative groups (risk of type II error). However, 556 prospectively documented patients were available and no significant difference in outcomes was detected. Length of stay was longer in our cohort as compared with previous reports, but still within the reported range of the international ERAS benchmarking included in the international ERAS database.20–22 Finally, overall compliance was not yet optimal despite the full implementation process, similar to other reports.12 ,14 We would expect improved outcomes for both comparative groups with higher compliance levels but no difference between patients operated on early or later during the week.

Staffing may be considered as generous on weekdays and during the weekend in Swiss hospitals compared with some other countries. This makes the application of complex and work-intensive care pathways easier than in healthcare systems with restricted resources. Furthermore, ERAS was implemented early in 2011 in our institution, and thus study patients were treated after the initial implementation process. It is therefore possible that our findings could not be reproduced in hospitals where ERAS implementation has not been firmly established.

In conclusion, compliance with the ERAS pathway was high for patients operated on early or late during the week. Minor differences in terms of urinary drainage and intravenous fluids had no impact on functional and clinical outcomes. While this is plausible with a long-standing programme with standardised measures and trained staff, it might be more challenging for teams in the beginning of the ERAS implementation process.