This study was designed aiming to analyze the risk factors contributing to ERAS failure in patients with IBD undergoing colorectal resection, and it revealed that preoperative NRS-2002 score≥3, preoperative mGPS=2, steroids use, and failure to mobilization on POD1 were the independent risk factors. To our knowledge, there are few studies on the association between perioperative factors and ERAS failure in such population. These risk factors provide a basis for us to identify patients who are prone to fail the ERAS procedure or to individually adjust the ERAS protocols.
Many studies considered the occurrence of postoperative complications as the primary endpoint of ERAS failure; however, this would overlook patients who recover slowly without surgical complications [14, 19]. For studies that assessed ERAS by focusing on LOS, the criteria for prolonged postoperative LOS were also inconsistent. Here, the 75th percentile of postoperative LOS in our center was set as criteria for delayed discharge, which was consistent with a recent study. In addition, reoperation and readmission or death within 30 days after surgery are also considered failures of ERAS.
In our cohort, a considerable proportion of patients were excluded in order to reduce the heterogeneity of the population, although they might also benefit from some components of ERAS. We excluded patients undergoing emergency surgery because they used adaptive ERAS strategies that might be different from elective surgery[22-24]. In addition, we excluded patients with small intestinal CD and focused on patients undergoing colorectal surgery with ERAS most widely implemented in this population.
Malnutrition is common in IBD patients with IBD and affects up to 70% population[25, 26]. Previous studies have shown that malnutrition was an independent risk factor for adverse postoperative outcome[27, 28]. In our study, preoperative NRS-2002 score≥3 was an independent risk factor for ERAS failure, which reminds us of the importance of optimization of preoperative nutritional status for the success of the ERAS project. Patients with malnutrition are prone to poorly healed incisions after surgery, and the incidence of infectious complications or organ dysfunction also increases due to impaired immune response[26, 30]. A recent study showed that long-lasting nutritional prehabilitation can have a positive impact on patient’s recovery with IBD after surgery. Therefore, the early identification and nutritional pre-adaptation of patients in need of surgery is very important for the patient’s postoperative recovery.
Previous studies showed that overall postoperative complications and LOS increased significantly along with the increase of mGPS for IBD patients. In the present study, we found that mGPS=2 was an independent risk factor for ERAS failure and the underlying relationship might be explained in several ways. First, preoperative CRP levels correlated with disease severity of IBD. Zuo et al have shown that preoperative CRP >10 mg/L was the risk factors for postoperative IAS complications of CD . Hypoalbuminemia was associated with impairment of immune function, causing impaired macrophage activation and inducing macrophage apoptosis. In addition, hypoalbuminemia can also cause tissue edema, which might affect intestinal peristalsis.Therefore, the presence of systemic inflammatory response such as elevated CRP levels and hypoalbuminemia should be routinely evaluated before surgery and be corrected if possible.
Glucocorticoids are widely used in IBD, especially for moderate to severe patients[36, 37]. Our study indicated that patients who have used steroids within 4 weeks before surgery were more likely to fail ERAS program. The results are consistent with previous research which found steroids have adverse impacts on postoperative outcomes, including infectious and non-infectious outcomes [38, 39]. Also, previous usage of steroids before surgery may reflect a more severe inflammatory response and disease severity.
In our study, the postoperative ERAS compliance was poor, which is consistent with previous studies. Univariate analysis showed that failure to postoperative ERAS items were all related to ERAS failure, in which failure to mobilization on POD1 was independent risk factors for ERAS failure. Early postoperative mobilization can promote the recovery of multiple systems such as respiratory, gastrointestinal, and musculoskeletal. In a subset analysis of the LAFA trial, early mobilization was significantly correlated with shorter hospital stay.Facts that improved compliance with the ERAS program can independently improve outcome after elective colorectal resection have been confirmed in a large, international cohort . Therefore, patients should be encouraged to be active mobilization early after surgery rather than bed rest.
The study has several limitations. First, this is a retrospective, single-center study, and some high-risk patients were excluded, thereby limiting the generalizability of the conclusion of the current study. Second, the purpose of our research is to early identify and intervene in patients who may fail in the ERAS program, so many postoperative indicators related to ERAS failure are not included[20, 42]. Third, there is currently no unified definition of ERAS failure, and further research and consensus of experts are needed.
In conclusion, the current study found that preoperative NRS-2002 score ≥3, preoperative mGPS=2, preoperative steroids use, and failure to mobilization on POD1 are independent risk factors associated with ERAS failure in IBD patients after colorectal resection. Preoperative nutritional prehabilitation, weaning off perioperative steroid and reducing preoperative inflammatory response, and improving the compliance of ERAS items may contribute to the success of ERAS in IBD patients.