World Journal of Surgery

, Volume 42, Issue 9, pp 2691–2700 | Cite as

The Impact of the Implementation of the Enhanced Recovery After Surgery (ERAS®) Program in an Entire Health System: A Natural Experiment in Alberta, Canada

  • Zaina AlBalawi
  • Leah Gramlich
  • Gregg Nelson
  • Peter Senior
  • Erik Youngson
  • Finlay A. McAlisterEmail author
Original Scientific Report



The Enhanced Recovery After Surgery (ERAS) program has been shown to reduce length of stay (LOS) in colorectal surgical patients in randomized trials. The impact outside of trial settings, or in subgroups of patients excluded from trials such as individuals with diabetes, is uncertain. We conducted this study to evaluate the impact of ERAS implementation in Alberta, Canada.


This is a retrospective cohort study and interrupted time series analysis using linked administrative data to examine LOS and postoperative outcomes in the 12 months pre- and post-implementation of ERAS in 2013 for all adults undergoing elective colorectal surgery.


Of 2714 patients (mean age 60.4 years, 55% men) with similar demographics and comorbidity profiles in the pre/post-ERAS time periods, LOS was significantly shorter post-ERAS (8.5 vs. 9.5 days, p = 0.01; − 0.84 days [95% CI − 0.04 to − 1.64 days] after adjustment for age, sex, Charlson comorbidity score, procedure type, surgical approach, and hospital). However, interrupted time series demonstrated no significant level change (p = 0.30) or change in slope (p = 0.63) with ERAS implementation, consistent with continuation of an underlying secular trend of reductions in LOS over time. There were no significant differences (in multivariate analysis or ITS) in risk of 30-day death/readmission (14.3% post vs. 13.5% pre-ERAS, aOR 1.12, 95% CI 0.89–1.40), 30-day death/ED visit (27.2% post vs. 30.0% pre, aOR 0.93, 95% CI 0.78–1.10), or 30-day death/readmission/ED visit (27.8% post vs. 30.6% pre, aOR 0.93, 95% CI 0.78–1.10). The 428 patients with diabetes had longer LOS but exhibited no significant difference post- versus pre-ERAS (10.7 vs. 11.6 days, p = 0.53; p = 0.56 for level change and p = 0.66 for slope change on ITS).


Although there was a secular trend toward decreasing LOS over time in Alberta, ERAS implementation was not associated with statistically significant changes in LOS or postoperative outcomes for all colorectal surgery patients or for those with diabetes. Our study highlights the importance of evaluating system changes (for both uptake and outcomes) rather than assuming trial benefits will translate directly into practice. Interventions to improve LOS and postoperative outcomes for patients with diabetes undergoing colorectal surgery are still needed even in the ERAS era.



This work was supported by the Alberta Strategy for Patient Oriented Research Support Unit Data Platform. The authors thank Mr. Edwin Rogers, M.A. (Senior Analyst, Clinical Analytics, Alberta Health Services) for assistance with colorectal surgery case definitions and logic, as well as access to the patient lists maintained by the ERAS team for cross-validation with our administrative data. They also extend their thanks to Jeff Bakal, Ph.D., P.Stat (Alberta SPOR Support Unit, University of Alberta) for assistance with study design and statistical methods and Peter Faris, Ph.D. (Director, Research Facilitation, Analytics, DIMR, Alberta Health Services) for statistical review. Zaina Albalawi and Erik Youngson had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Compliance with ethical standards

Conflict of interest

None of the authors have any conflict of interest relating to this study.


  1. 1.
    Ljungqvist O, Scott M, Fearon KC (2017) Enhanced recovery after surgery. A review. JAMA Surg 152:292–298CrossRefPubMedGoogle Scholar
  2. 2.
    Liu VX, Rosas E, Hwang J, Cain E, Foss-Durant A, Clopp M et al (2017) Enhanced recovery after surgery program implementation in 2 surgical populations in an integrated health care delivery system. JAMA Surg 152:e171032CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    ERAS Compliance Group (2015) The impact of enhanced recovery protocol compliance on elective colorectal cancer resection: results from an international registry. Ann Surg 261(6):1153–1159CrossRefGoogle Scholar
  4. 4.
    Gustafsson UO, Scott MJ, Schwenk W et al (2012) Guidelines for perioperative care in elective colonic surgery: enhanced recovery after surgery (ERAS®) society recommendations. Clin Nutr 31(6):783–800CrossRefPubMedGoogle Scholar
  5. 5.
    Greco M, Capretti G, Beretta L, Gemma M, Pecorelli N, Braga M (2014) Enhanced recovery program in colorectal surgery: a meta-analysis of randomized controlled trials. World J Surg 38(6):1531–1541. CrossRefPubMedGoogle Scholar
  6. 6.
    Gustafsson UO, Hausel J, Thorell A, Ljungqvist O, Soop M, Nygen J (2011) Adherence to the enhanced recovery after surgery protocol and outcomes after colorectal cancer surgery. Arch Surg 146(5):571–577CrossRefPubMedGoogle Scholar
  7. 7.
    Albalawi Z, Laffin M, Gramlich L, Senior P, McAlister FA (2017) Enhanced recovery after surgery (ERAS(®)) in individuals with diabetes: a systematic review. World J Surg 41:1927–1934. CrossRefPubMedGoogle Scholar
  8. 8.
    Quan H, Sundararajan V, Halfon P et al (2005) Coding algorithms for defining comorbidities in ICD-9-CM and ICD-10 administrative data. Med Care 43(11):1130–1139CrossRefPubMedGoogle Scholar
  9. 9.
    Quan H, Li B, Saunders LD et al (2008) Assessing validity of ICD-9-CM and ICD-10 administrative data in recording clinical conditions in a unique dually coded database. Health Serv Res 43(4):1424–1441CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Charlson ME, Pompei P, Ales KL, MacKenzie CR (1987) A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis 40(5):373–383CrossRefPubMedGoogle Scholar
  11. 11.
    Aarts MJ, Lemmens VEPP, Louwman MWJ, Kunst AE, Coebergh JWW (2010) Socioeconomic status and changing inequalities in colorectal cancer? A review of the associations with risk, treatment and outcome. Eur J Cancer Oxf Engl 1990 46(15):2681–2695Google Scholar
  12. 12.
    Ma C, Crespin M, Proulx M-C et al (2012) Postoperative complications following colectomy for ulcerative colitis: a validation study. BMC Gastroenterol 12:39CrossRefPubMedPubMedCentralGoogle Scholar
  13. 13.
    Dindo D, Demartines N, Clavien P-A (2004) Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg 240(2):205–213CrossRefPubMedPubMedCentralGoogle Scholar
  14. 14.
    Rosenthal R, Hoffmann H, Clavien P-A, Bucher HC, Dell-Kuster S (2015) Definition and classification of intraoperative complications (CLASSIC): Delphi study and pilot evaluation. World J Surg 39(7):1663–1671. CrossRefPubMedGoogle Scholar
  15. 15.
    McAlister FA, Bakal JA, Majumdar SR et al (2014) Safely and effectively reducing inpatient length of stay: a controlled study of the General Internal Medicine Care Transformation Initiative. BMJ Qual Saf 23(6):446–456CrossRefPubMedGoogle Scholar
  16. 16.
    Lau CSM, Chamberlain RS (2017) Enhanced recovery after surgery programs improve patient outcomes and recovery: a meta-analysis. World J Surg 41:899–913. CrossRefPubMedGoogle Scholar
  17. 17.
    Gillissen F, Hoff C, Maessen JMC et al (2013) Structured synchronous implementation of an enhanced recovery program in elective colonic surgery in 33 hospitals in The Netherlands. World J Surg 37(5):1082–1093. CrossRefPubMedGoogle Scholar
  18. 18.
    Nelson G, Kiyang LN, Crumley ET et al (2016) Implementation of enhanced recovery after surgery (ERAS) across a provincial healthcare system: the ERAS Alberta Colorectal Surgery Experience. World J Surg 40(5):1092–1103. CrossRefPubMedGoogle Scholar
  19. 19.
    Thiele RH, Rea KM, Turrentine FE, Friel CM, Hassinger TE, Goudreau BJ et al (2015) Standardization of care: IMpact of an Enhanced Recovery protocol on length of stay, complications, and direct costs after colorectal surgery. J Am Coll Surg 220:430–443CrossRefPubMedGoogle Scholar
  20. 20.
    Schnüriger B, Barmparas G, Branco BC, Lustenberger T, Inaba K, Demetriades D (2011) Prevention of postoperative peritoneal adhesions: a review of the literature. Am J Surg 201(1):111–121CrossRefPubMedGoogle Scholar
  21. 21.
    Okabayashi K, Ashrafian H, Zacharakis E et al (2014) Adhesions after abdominal surgery: a systematic review of the incidence, distribution and severity. Surg Today 44(3):405–420CrossRefPubMedGoogle Scholar
  22. 22.
    Ramsay CR, Matowe L, Grilli R, Grimshaw JM, Thomas RE (2003) Interrupted time series designs in health technology assessment: lessons from two systematic reviews of behavior change strategies. Int J Technol Assess Health Care 19(4):613–623CrossRefPubMedGoogle Scholar
  23. 23.
    Zhang F, Wagner AK, Ross-Degnan D (2011) Simulation-based power calculation for designing interrupted time series analyses of health policy interventions. J Clin Epidemiol 64(11):1252–1261CrossRefPubMedGoogle Scholar
  24. 24.
    Bernal JL, Cummins S, Gasparrini A (2017) Interrupted time series regression for the evaluation of public health interventions: a tutorial. Int J Epidemiol 46(1):348–355PubMedGoogle Scholar

Copyright information

© Société Internationale de Chirurgie 2018

Authors and Affiliations

  • Zaina AlBalawi
    • 1
  • Leah Gramlich
    • 2
  • Gregg Nelson
    • 3
  • Peter Senior
    • 1
  • Erik Youngson
    • 4
  • Finlay A. McAlister
    • 4
    • 5
    Email author
  1. 1.Division of Endocrinology, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonCanada
  2. 2.Division of Gastroenterology, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonCanada
  3. 3.Surgical Lead, ERAS Alberta and Department of Oncology, Cumming School of MedicineUniversity of CalgaryCalgaryCanada
  4. 4.Alberta SPOR Support UnitUniversity of AlbertaEdmontonCanada
  5. 5.5-134C Clinical Sciences Building, Division of General Internal Medicine, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonCanada

Personalised recommendations