Impact of Preoperative Anemia on Outcomes of Enhanced Recovery Program After Colorectal Surgery: A Monocentric Retrospective Study

Abstract
Background Anemia is common before major abdominal surgery (35%). It is an independent factor for postoperative complications and longer length of stay (LOS). The aim of this study was to evaluate the extent to which preoperative anemia impacts on enhanced recovery programs (ERP) outcomes.
Materials and Methods The data for patients scheduled for colorectal surgery between 2015 and 2019, were analyzed (n = 494). All patients were managed with the same ERP. Demographic data, preoperative risk factors, postoperative complications, LOS and adherence to ERP were compared between anemic and non-anemic patients. Anemia was defined by a hemoglobin concentration < 13 g dL-1 in men and < 12 g dL-1 in women.
Results and Discussion In total, 173 patients had preoperative anemia. They were older (p<0.001) and more often male (p = 0.02). The following risk factors were significantly more frequent in the anemic group: renal failure (p = 0.04), malnutrition (p<0.001), cardiac arrhythmia (p<0.001), coronaropathy (p = 0.02) and anticoagulant treatment (p<0.001). Despite more risk factors, anemic patients did not experience more postoperative complications (38.2% vs. 31.2%, p = 0.12). Overall adherence to ERP was similar (18 [16–19] vs. 18 [17–19], p = 0.06).
LOS was 4 [3–7] and 3 [2–6.25] days in the anemic and the non-anemic groups, respectively (p\0.002). Multivariate analysis showed that anemia did not affect LOS (p = 0.27).
Conclusion Our study suggests that preoperative anemia does not detract from the benefits of ERP after elective colorectal surgery.